Lasers in Dermatological Practice [PDF] [UnitedVRG]

LASERS

in Dermatological Practice

LASERS

in Dermatological Practice Editors

Kabir Sardana MD DNB MNAMS Professor Department of Dermatology and STD Maulana Azad Medical College New Delhi, India

Vijay K Garg MD MNAMS Director–Professor and Head Department of Dermatology and STD Maulana Azad Medical College New Delhi, India

Forewords

Ganesh S Pai B Krishna Rau

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Website: www.jaypeebrothers.com Website: www.jaypeedigital.com © 2014, Jaypee Brothers Medical Publishers The views and opinions expressed in this book are solely those of the original contributor(s)/author(s) and do not necessarily represent those of editor(s) of the book. All rights reserved. No part of this publication may be reproduced, stored or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission in writing of the publishers. All brand names and product names used in this book are trade names, service marks, trademarks or registered trademarks of their respective owners. The publisher is not associated with any product or vendor mentioned in this book. Medical knowledge and practice change constantly. This book is designed to provide accurate, authoritative information about the subject matter in question. However, readers are advised to check the most current information available on procedures included and check information from the manufacturer of each product to be administered, to verify the recommended dose, formula, method and duration of administration, adverse effects and contraindications. It is the responsibility of the practitioner to take all appropriate safety precautions. Neither the publisher nor the author(s)/editor(s) assume any liability for any injury and/or damage to persons or property arising from or related to use of material in this book. This book is sold on the understanding that the publisher is not engaged in providing professional medical services. If such advice or services are required, the services of a competent medical professional should be sought. Every effort has been made where necessary to contact holders of copyright to obtain permission to reproduce copyright material. If any have been inadvertently overlooked, the publisher will be pleased to make the necessary arrangements at the first opportunity. Inquiries for bulk sales may be solicited at: [email protected] Lasers in Dermatological Practice First Edition: 2014 ISBN 978-93-5152-300-0 Printed at

Dedicated to My colleagues, friends and foes, the last of which goad us to better ourselves constantly…… My wife Dr Supriya, who helps me to keep the balance between family and academics My daughter Zoya, who is the ‘zing’ in my life My parents, Mrs Amba Sardana and Major General Sardana who have instilled discipline in my life and Lastly, the Department where over the years we have honed the skills in laser intervention —Kabir Sardana

My family and friends My wife Mrs Manju Garg, who has stood by me through times of strife My son Devansh, who is pursuing his MBBS and My daughter Dr Ekta, who is a dentist —Vijay K Garg

Contributors Anil Aggrawal MD Forensic Medicine (AIIMS) Director-Professor Forensic Medicine Maulana Azad Medical College New Delhi, India Anil Ganjoo MBBS MD Senior Consultant Dermatologist and Head of Dermatology Sunderlal Jain Hospital Saroj Hospital and INMAS New Delhi, India Anjali Madan MD Senior Resident Department of Dermatology Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India Anuj Tenani MBBS PGY-II Department of Dermatology Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India Anusha H Pai MD Consultant Dermatologist Derma-Care Skin and Cosmetology Center Mangalore, Karnataka, India Atul M Kochhar MD DNB MNAMS FAAD Senior Specialist–Grade I Department of Dermatology and STD Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India Banwari Jangid MD Department of Dermatology and Venereology All India Institute of Medical Sciences New Delhi, India

Dharmendra Karn MD Dermatologist Dhulikhel Hospital Kathmandu University Teaching Hospital Kavre, Nepal Ganesh S Pai MD DVD Senior Consultant Dermatologist Derma-Care Skin and Cosmetology Center Mangalore, Karnataka, India Inder Raj S Makin MBBS (India) Dipl-Ing (Germany) RDMS PhD (USA)

Associate Professor AT Still University School of Osteopathic Medicine in Arizona (SOMA) Arizona School of Dentistry and Oral Health (ASDOH) Mesa, USA Jaspriya Sandhu MBBS PGY-I Department of Dermatology Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India Kabir Sardana MD DNB MNAMS Professor Department of Dermatology Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India Khushbu Goel MD Pool Officer Department of Dermatology Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India

viii  Lasers in Dermatological Practice Narendra Kamath MD DVD Consultant Dermatologist Cutis Skin Care Center Mangalore, Karnataka, India Pavithra S Bhat MD Kovai Medical Center and Hospital Coimbatore, Tamil Nadu, India Payal Chakravarty MD Senior Resident Department of Dermatology Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India Rashmi Ranjan MD Senior Resident Department of Dermatology Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India Rashmi Sarkar MD MNAMS Professor Department of Dermatology Maulana Azad Medical College and LN Hospital New Delhi, India Chief Founder and Honorary Secretary Pigmentary Disorders Society New Delhi, India Shahin S Nooreyezdan MBBS MS MCh (Plastic Surgery) PGIMER Chandigarh

Senior Consultant Department of Plastic, Cosmetic and Reconstructive Surgery Indraprastha Apollo Hospitals New Delhi, India Shikha Bansal MD DNB MNAMS Specialist Department of Dermatology Safdarjung Hospital New Delhi, India Shivani Bansal MD Senior Resident Department of Dermatology Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India

Simal Soin PG Dermatology (St Johns Institute of Dermatology) London MPhil Cambridge University UK

Medical Director and Chief Cosmetic Dermatologist Three Graces New Delhi, India Soni Nanda MD (Dermatology) Shine and Smile Skin Clinic Max Super Specialty Hospital New Delhi, India Sujay Khandpur MD DNB MNAMS Professor Department of Dermatology and Venereology All India Institute of Medical Sciences New Delhi, India Twinkle Daulaguphu MBBS PGY-I Department of Dermatology Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India Vanya Narayan MBBS PGY-III Department of Dermatology Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India Vijay K Garg MD MNAMS Director-Professor and Head Department of Dermatology Maulana Azad Medical College and Lok Nayak Hospital New Delhi, India Vivek Nair MBBS MD Consultant Dermatologist Dr Nair’s Skin Clinic (Palam Vihar) Clinic Dermatech (Vasant Vihar and Gurgaon) Metro Hospital (Palam Vihar) New Delhi, India

Foreword Lasers have moved from the fringe of dermatology to a more centrist path over the past decade. Fifteen years ago, when lasers trickled into our country, they were considered to be exotic and perhaps accessible to a select few. Cosmetic dermatology and lasers have grown by leaps and bounds and that necessitates that they are absorbed in the mainstream. With close to half of the dermatologists now owning or having access to lasers, it is important that our younger generation of dermatologists have access to good practical textbooks as well as high quality equipment. This book, Lasers in Dermatological Practice is best suited to educate our specialty about the perils and pitfalls of using lasers. Indian skin is unique since it comes commonly in 3 types—IV, V, VI. Parameters will therefore vary depending on the skin types, a dilemma that western books do not address. Postinflammatory hyperpigmentation will vary in each skin type and even show variation among patients in a single skin type. Such unpredictability and perplexing results are a cause of anxiety in a cosmetologist at an inflexion point in his career. A comforting thought is that our patients, except for a miniscule minority, are forgiving and compliant. Most cases of tissue damage by laser will heal over time, nature coming to our rescue. Our patience and reassurance will comfort patients in the interim period. In clinical dermatology, we have a chance to assess, judge and treat patients. If there is an error of management, we can apply a midcourse correction and modify therapy. Unfortunately, this is not true of lasers. A mistake made, a poor assessment, using more or less power than required can lead to laser burns and scarring. If it is on the face, as it is most of the time, the consequences are not difficult to portend. Since there is no second chance to repair damage, it is important to understand the basics of lasers and the specifics of equipment much like reading a car manual before driving your new car. This book does both and will hopefully lead to confident cosmetologists and happy patients. Ganesh S Pai MD DVD FAAD Medical Director Derma-Care Skin and Cosmetology Center, The Trade Center Director-Professor, Department of Dermatology KS Hegde Medical College, Deralakatte Mangalore, Karnataka, India

Foreword I thank the authors for giving me the opportunity to write the Foreword to this excellent book, Lasers in Dermatological Practice. The editors along with the co-authors have put down their vast experience in the use of laser in various dermatological conditions. It is a book of international standards and, in particular, reference to the application of lasers in brown and dark skin patients. Basics of laser in relation to skin lesions are well-written. The use of the different lasers in different dermatological lesions and the step-by-step approach to each and every lesion is superb. The practical tips to avoid wrong outcome is well-documented. The use of non-laser energy sources in dermatological practice is very illuminating. The references at the end of each chapter are apt and to the point. The chapter on medicolegal aspects is pertinent and informative. On the whole, it is the end result of the vast experience over the years that the editors have acquired to write this book. I am confident that this book will find a place in all dermatologists library.

B Krishna Rau MS FRCS (Eng and Edin) FRCS (Thailand) (Hon) FIAMS FACG FICS FIGSC

Professor-Emeritus, Dr MGR Medical University Honorary Fellow, American Surgical Association President, World Federation of Society for Laser and Surgery Medicine Chennai, Tamil Nadu, India

Preface The genesis of this book arose from the common mechanistic approach where we learn which buttons to push, in courses provided by the more reputable device manufacturers just after a laser is purchased. This approach is foolish beyond words, and can harm patients, and worse create medicolegal hazards. There are some excellent books that we have referred to but most of them deal with technologies that are nice to hear but too expensive to use in India. Our book was initially planned as a companion to the hands on workshop where the nitty gritty was left out while the topic in focus was discussed. Thus the first edition was done with the help of Sun Pharmaceuticals. This edition is the combined effort of Abbot and the vision of Shri Jitendar P Vij, who convinced us to make it an elaborate yet compact book. The book answers the three basic questions, what to do, why to do it and how to do it? But our basic target is the dermatologists who need a step-bystep approach to the technology commonly used and not the laser that a speaker in most conferences uses, which as a thumb rule is expensive, the reason why the company sponsors the talk in the first place! Though the FDA gives clearance of a device for a particular labeled indication, this cannot be taken as any assurance that it will work safely and effectively enough to satisfy the patients. Tragically, it may not be an understatement that a majority of lasers bought in this country are not US FDA approved in the first place! The book will also look at some questions that we rarely ask. What is the histological depth of fractional lasers? Which type of atrophic scar actually responds? Is Fr CO2 superior to Er:Glass? And many others. As the field of cosmetic intervention usually encompasses indications where novel non-laser technologies are used, we have covered radio­ frequency, focused USG, plasma resurfacing and LED. The book is planned in such a way where the commonly performed procedures are discussed which gradually move on the advanced techniques. Practical aspects like medicolegal hazards and pearls are discussed in the latter half of the book. Some very useful information is provided in the appendices. Our contributors are largely those who are experts in their field of interest. Our own work spanning over 8 years, with almost 5,000 procedures helped us to bridge the gap between theory and practice. But this is not a “Cook Book” and only a guide on the best approach is provided. Individual laser parameters can vary, thus there is no substitute for hands-on training, which cannot be obtained in this book or sitting in a lecture hall more so when there are hundreds sitting in it! Hope you like the effort. More will follow soon… Kabir Sardana Vijay K Garg

Acknowledgments We would like to thank our faculty residents and students of the department some who have left to join other institutions, for their role in establishing and developing the Laser Clinic at Maulana Azad Medical College (MAMC), New Delhi, India. Special thanks to Dr Vijay K Garg, Director-Professor and Head, Department of Dermatology and STD, MAMC, who through his administra­ tive acumen, managed to get the lasers. He has given me great support and has served as a mentor throughout my professional career. His guidance and encouragement over the years have influenced my efforts. A special thanks to the team at M/s Jaypee Brothers Medical Publishers (P) Ltd, New Delhi, India, especially Shri Jitendar P Vij (Group Chairman) and Mr Ankit Vij (Managing Director), for latching on to the project, Mr PN Venkatraman (Vice President-International), Mr Shashikumar Sambhoo, for handling the publicity and sales and Mr Tarun Duneja (Director-Publishing), Mr Subrata Adhikary (Commissioning Editor), Mr Lalit kumar (DTP Operator) for helping with the deadlines. A big thanks to our contributors, some of whom who have worked on their chapter on a one month deadline! Each of them is an expert in their field. Dr Simal Soin, Dr Shahin Nooreyezdan, Dr Inder Raj S Makin and Dr Vivek Nair have worked on such a deadline. Dr Inder Raj S Makin has also been kind enough to review two chapters for us and his comments have been an asset to the chapters. Dr Khandpur and Dr Anil Agarwal have also contributed after taking out time from their busy schedule. Dr Atul M Kochhar who is also the Purchase Officer at our Hospital has given nuances of buying lasers. A big thanks to Dr Antje Katzer (Ascepelion), for letting us use the images of the company’s devices. And lastly, our tributes to the countless patients who have taught us dermatology and helped us to learn and relearn lasers!

xvi  Lasers in Dermatological Practice

Real knowledge is to know the extent of one’s ignorance —Confucius

Never sacrifice your dignity to make money, but charge what you are worth —Christopher B Zachary

Contents Section 1: Conventional Laser Interventions

1. Basics of Laser-Tissue Interactions 2. Ablative Lasers  Overview 25  Ablative Laser Treatment of Common Conditions 52  Step by Step Approach 86  Atlas 93 3. Pigmented Lesions and Tattoos  Overview 101  Lasers For Tattoo Removal 115  Laser Treatment of Common Pigmented Conditions 131  Step by Step Approach 160  Atlas 163 4. Fractional Photothermolysis  Overview 172  Laser Treatment of Common Conditions 204  Step by Step Approach 229  Atlas 233 5. Vascular Lasers 6. Lasers for Hair Removal 

3 25

101

172

236 252

Section 2: Advanced Laser Interventions 7. Nonablative and Subsurface Rejuvenation  Step by Step Approach 291 8. Nonsurgical Tightening  9. Aesthetic Intense Focused Ultrasound (IFUS): Clinical Perspective on Fitzpatrick Skin Types III–VI 10. Noninvasive Body Contouring 11. Lasers for Scars, Keloids, and Stretch Marks

275 294 319 336 361

Section 3: Practical Aspects and Advances 12. 13. 14. 15. 16. 17. 18.

Miscellaneous Laser Responsive Disorders How to Start a Laser Practice (Private Setup) How to Set up a Laser Clinic in a Public Funded Institution Therapeutic Pearls in Lasers Medicolegal Aspects of Lasers in Dermatological Practice Complications and their Management New Aspects and Controversies in Lasers

379 416 421 432 441 455 471

xviii  Lasers in Dermatological Practice

Appendices Appendix 1: Appendix 2: Appendix 3: Appendix 4: Appendix 5: Appendix 6: Appendix 7: Appendix 8: Appendix 9:

Laser Safety/Eye Care Consent Form Procedure Checklist Postoperative Care Sample Operative Note Sample Postoperative Instructions (Ablative Lasers) Patient Information Sheet Local Anesthetics Select Bibliography

Laser and Medical Devices (Index)

493 504 506 507 512 513 514 528 538 541

Index543

Section

Conventional Laser Interventions

1

Chapter

1

Basics of Laser-Tissue Interactions Kabir Sardana, Vijay K Garg, Shivani Bansal, Jaspriya Sandhu, Twinkle Daulaguphu

Medical lasers have evolved over the years with numerous applications. Dermatologic laser surgery is regarded as one of the fastest growing areas in the emerging fields of photomedicine and biomedical optics. As with any device, the most efficacious and appropriate use requires an understanding of the basic photobiological and photophysical principles of laser-tissue interaction as well as the properties of the laser itself. This chapter provides a brief description of the nature of the laser, how it works, and the fundamental mechanisms of its interaction with human skin.

Light Light represents one portion of a much broader electromagnetic spectrum. Light can be divided into the UV (200–400 nm), VIS (400–700 nm), NIR “I” (755–810 nm), NIR “II” (940–1,064 nm), MIR (1.3–3 mm), and Far IR (3 mm and beyond) (Fig. 1.1). Normally, the percentage of incident light reflected from the skin surface is determined by the index of refraction difference between the skin surface (stratum corneum n = 1.55) and air (n = 1). About 4–7% of light is typically reflected and is called the Fresnel reflectance because it follows Fresnel’s equations relating reflectance to the angle of incidence, plane of polarization, and refractive index. The angle between the light beam and the skin surface determines the percentage of reflected light. More light is reflected at “grazing” angles of incidence. It follows that, to minimize surface losses, in most laser applications, one should deliver light approximately perpendicular to the skin. One can deliberately angle the beam, on the other hand, to decrease penetration depth and also attenuate the surface fluence by “spreading” the beam. On the other hand, the surface of dry skin reflects more light because of multiple skin-air interfaces (hence the white appearance of a psoriasis plaque). The light penetration into the epidermis depends on the wavelength dependent absorption and scattering. Because of scattering, much incident light is remitted (remittance refers to the total light returned to the

4  Lasers in Dermatological Practice

Fig. 1.1: Absorption spectrum of various lasers in relation to the major chromophores

environment due to multiple scattering in the epidermis and dermis, as well as the regular reflection from the surface). In laser surgery, light reflected from the surface is typically “wasted”. This “lost” energy varies from 15% to as much as 70% depending on the wavelength and the skin type. For example, for 1,064 nm, 60% of an incident laser beam may be remitted. Tissue effects occur only when light is absorbed. The absorption coefficient is defined as the probability per unit path length that a photon at a particular wavelength will be absorbed and it depends on the concentration of chromophores (absorbing molecules) present. The three primary skin chromophores are water, hemoglobin and melanin (Fig. 1.1). Chromophores exhibit characteristic bands of absorption at certain wavelengths. For example, melanin absorbs broadly across the visible and ultraviolet (UV) spectrum, the oxyhemoglobin and reduced hemoglobin in blood exhibit strong bands in the UV, blue, green and yellow regions. Water has strong absorption in the infrared (IR) region (Fig. 1.1). Optical properties of the epidermis and dermis are different. In pigmented epidermis, melanin absorption is usually the dominant process over the majority of the optical spectrum (200–1000 nm) (Fig. 1.1). In the dermis, there is strong, wavelength-dependent scattering by collagen fibers, which attenuates penetration of light. This scattering varies inversely with wavelength. Thus as a thumb rule, between 280 nm and 1300 nm, the depth

Basics of Laser-Tissue Interactions  5

of penetration increases with wavelength. Above 1300 nm, penetration decreases due to the absorption of light by water. The most deeply penetrating wavelengths are 650–1200 nm, while the least penetrating wavelengths are within the far-UV and far-IR regions.

Types of Light Devices Lasers contain four main components, the lasing medium, the excitation source, feedback apparatus and an output coupler. The amplifier of a laser is the laser material that can be a solid, a gas, or a liquid. The feedback mechanism is produced by the resonator, where the light is reflected by two mirrors so that the photons pass several times through the laser material. The number of photons within the resonator increases exponentially due to the stimulated emission (Fig 1.2). With respect to lasing media, there are diode lasers, solid-state lasers, dye and gas lasers. Solid-state lasers include the Nd:YAG laser, Er:YAG laser, alexandrite laser and the ruby laser. The gas lasers include the carbon dioxide (CO2) laser, argon ion laser and the excimer lasers, while the diode and dye lasers are singular in their class.

Light Device Terminology Basic parameters for light sources are power, time and spot size for continuous wave lasers and for pulsed sources, the energy per pulse, pulse duration, spot size, fluence, repetition rate and the total number of pulses (Table 1.1). At least for most ablative lasers, the effect of the laser beam on human skin can be affected by any of three variables: power, time and spot size. The effects of power and time are proportional whereas that of spot size (radius) is an inverse square. If either the power or time is doubled, fluence increases by a factor of 2. However, if the spot size is decreased by a factor of 2, fluence increases by a factor of 4. Doubling the spotsize results in a four-fold reduction in fluence.

Fig. 1.2: Various output modes of a conventional laser

6  Lasers in Dermatological Practice Table 1.1 Various terminologies used in lasers Power P (W)

For Cw lasers

Energy E = (J)

For Cw lasers

Power density W/A (irradiance) (W/cm2) (A = effective area)

For Cw lasers

Peak power P max (W)

For pulsed lasers

Energy E per pulse (J)

For pulsed lasers

Pulse duration t [fs (10 ) to ms (10−3)]

For pulsed lasers

Energy density E/A (radiant exposure) (J/cm2) (A = effective area)

For pulsed lasers

−15

Cw: continuous wave, fs: femtosecond, ms: millisecond

Energy: Measured in Joules (J). Fluence: The amount of energy delivered per unit area is the fluence, sometimes called the dose or radiant exposure, given in J/cm2 Power: The rate of energy delivery is called power, measured in watts (W). One watt is one joule per second (W = J/s). Density: The power delivered per unit area is called the irradiance or power density, usually given in W/cm2. Pulse width :Laser exposure duration (called pulse width for pulsed lasers) is the time over which energy is delivered. Thus the lasers may be continuous, pulsed, quasi continuous and Q-switched (Fig. 1.3). The older lasers had pulse durations that varied from seconds to milliseconds (0.01s/10-3). Millisecond CO2 lasers are gated lasers but largely continuous wave in nature. The CO2 laser is a classic example of a continuous mode laser. Microsecond lasers (0.000001 sec/10-6) are the ideal ultrapulse lasers. Most Er:YAG lasers are also microsecond lasers. Another example is that of the PDL where a single or a train of pulses is emitted. Pseudocontinuous lasers (KTP) have very short pulses of light repeated at very high repetition rates. Extremely short pulses are achieved by Q-switching. These nanosecond lasers (0.000000001 s/10–9) are used in pigmented lesions (Q-switched lasers). Recently picoseconds (0.000000000001 s/10-12) have been used in tattoos. Power density: It is a critical parameter, for it often determines the action mechanism in cutaneous applications. For example, a very low irradiance emission (typical range of 2–10 mW/cm2) does not heat tissue and is associated with diagnostic applications, photochemical processes and biostimulation. On the other extreme, a very short nanosecond (ns) pulse can generate high peak power densities associated with shock waves and even plasma formation.

Basics of Laser-Tissue Interactions  7

Fig. 1.3: A figurative depiction of the energy and duration of lasers based on the pulse width

Spot Size: Another factor is the laser exposure spot size (which greatly affects the beam strength inside the skin). Other important factors include aspects of the incident light (convergent, divergent or diffuse) and the uniformity of irradiance over the exposure area (spatial beam profile). The pulse profile, that is, the character of the pulse shapes in time (instantaneous power versus time) also affects the tissue response. Operational modes: The Operational modes of lasers are Cw, pulsed as interrupted radiation (in ms), pulsed free running (in hundreds of ms), Q-switched (in ns) or mode-locked (in fs). Continuous wave (Cw) laser may be differentiated from a pulsed laser, which provides bursts of energy. In the Cw mode, the laser delivers a continuous beam of light with little or no variation in power output over time (Fig. 1.3). In Cw operation, laser output is controlled by the physician, typically by depressing a foot pedal. Interrupted radiation of a cw laser is done by mechanical or electronic switching with modification of the pulse length. The pulse frequency is low to moderate, up to 100 Hz. Flash lamp pumped solid-state lasers in the freerunning mode have pulse lengths of 50 ms up to several hundred micro­ seconds. Pulses of medical dye lasers systems can vary from microseconds to 50 ms. Superpulse is a term specific to some carbon dioxide lasers that

8  Lasers in Dermatological Practice

have been modified to produce very short pulses with high peak powers in a repetitive fashion, commonly several hundred pulses per second. Q-switching: Shorter pulses with very high intensities in the nanosecond range are produced by Q-switching of the laser. The single, intense pulse with a duration on the order of nanoseconds is produced. With Q-switching (the Q-factor stands for “quality factor,” used in electronics theory terminology), a fast electromagnetic switch (Pockel cell) in the laser cavity causes excitation of the active medium to build-up far in excess of the level of the medium when the shutter is open. In operation, the flashlamp is turned on and the population inversion gradually grows. Lasing is prevented by the shutter. When the population inversion is at a maximum, the shutter is opened so that lasing occurs and a large burst of energy is emitted as the cavity rapidly depletes the population inversion. The net result is an extremely high peak power (greater than 106 W) nanosecond duration pulse or series of pulses. Ultrashort laser pulses are generated by mode-coupling due to the coherent properties of the laser. Compared to Q-switching, where the shortest pulse durations are in the range of the resonator period, mode-coupling can generate even shorter laser pulses.

Beam Profiles: Top Hat versus Gaussian Laser beam profiles vary based on intercavity design, lasing medium and the delivery system. A common profile is Gaussian or bell-shaped (Fig. 1.4). For

Fig. 1.4 : Comparison of the beam types of lasers. In most indications, the top hat profile is preferred. The lower half of the figure demonstrates the conversion of a Gaussian beam into a top hat beam, which can be achieved in certain laser

Basics of Laser-Tissue Interactions  9

many lasers, this profile represents the fundamental optimized “mode” of the laser. This shape is usually observed when the beam has been delivered through an articulated arm. For some wavelengths, this is an effective way to deliver energy (CO2 and Erbium). The disadvantage of the rigid arm is limited flexibility, the typically short arm length, the possibility of misalignment from even minor impact and a tendency for nonuniform heating across the spot. The top hat beam ideally is better as there is uniform heating of the tissue. Sometimes a bell-shaped profile is desirable, for example, when applying a small spot FIR beam with a scanner. In this scenario, the wings of the beam allow for some overlap without delivering “too much” energy at points of overlap. The Gaussian profile can be modified outside the cavity, which is desirable in many applications. With a fiber equipped delivery system, the beam is mixed within the fiber and can be shaped to be more flat-topped.

Wavelength Ranges and Clinical Application A useful way of understanding the effects and clinical application of wavelength is to understand the interaction and depth of the different wavelength in relation to the primary chromophores (Fig. 1.5). 1. UV laser and light sources have been used primarily for treatment of inflammatory skin diseases and/or vitiligo, as well as striae. The XeCI excimer laser emits at 308 nm, near the peak action spectrum for psoriasis. The penetration is restricted to the epidermis (Fig. 1.5). 2. Violet IPL emissions, low power 410 nm LED and fluorescent lamps are used either alone or with ALA.

Fig. 1.5: Optical penetration depth of common lasers used in dermatology

10  Lasers in Dermatological Practice

3. Green Yellow (GY): These wavelengths are highly absorbed by hemoglobin (Hgb) and melanin and are especially useful in treating epidermal pigmented lesions and superficial vessels (Figs. 1.1 and 1.5). There are two issues concerning these lasers, one is their poor penetration in skin (and the even poorer penetration in blood) which makes them poor choices for treatment of deeper pigmented lesions or deeper larger vessels. Similarly they are not useful for permanent hair reduction (with the possible exception of very large spots (i.e., IPL) that enhance light depth). The effective portions of many IPL spectra include the GY range. By the proper manipulation of a laser delivery device, one can optimize parameters for selective heating of pigmented versus vascular lesions. Practical aspects of GY laser manipulation: A. Applying a compression handpiece without cooling with 595 nm, blood is depleted as a target and pigment is preferentially heated. B. If the pulse duration is reduced to the nanosecond range, melanosomes are preferentially heated over vessels. For example, extremely short Q-switched 532 nm pulses will cause fine vessels to rupture, but inadequate heat diffusion to the vessel wall precludes long-term vessel destruction. On the other hand, melanosomes are sufficiently heated for single-session lentigo destruction. By choosing specific wavelengths with respect to hemoglobin and melanin, one can achieve some degree of selective melanin or hemoglobin heating. 4. Red and Near IR (I) (630, 694, 755, 810 nm): Deeply penetrating red light (630 nm) continuous wave devices are efficient activators of protoporphyrin after topical application of ALA. The 694 nm (ruby) laser is optimized for pigment reduction and hair reduction in lighter skin types. The 810 nm diode and 755 nm alexandrite laser, depending on spot size, cooling, pulse duration and fluence can be configured to optimize outcomes for hair reduction, lentigines or blood vessels. They are positioned in the absorption spectrum for blood and melanin between the GY wavelengths and 1,064 nm (Fig. 1.5). They will penetrate deeply enough in blood to coagulate vessels up to 2 mm; also, they are reasonably tolerant of epidermal pigment in hair reduction (with surface cooling) as long as very dark skin is not treated. By decreasing the pulse width into the nanosecond range, the alexandrite laser is a first line treatment for many tattoo colors. 5. Near IR (II) 940 and Nd:YAG (1,064 nm): These two wavelengths have been used for a broad range of vessel sizes on the leg and face. They occupy a unique place in the absorption spectrum of the “3” chromophores, that is blood, melanin and water. Because of the depth of penetration (on the order of mm), they are especially useful for hair reduction and coagulation of deeper blood vessels. By varying fluence and spot size, reticular ectatic veins, as well as those associated with

Basics of Laser-Tissue Interactions  11

nodular port wine stains or hemangiomas, can be safely targeted. On the other hand, they are not well-suited for epidermal pigmented lesions. 6. Mid infrared lasers and deeply penetrating halogen lamps: These lasers and lamps heat tissue water. The absorption coefficients for the 1320, 1450, and 1540 nm systems are –3, 20 and 8 cm-1, respectively and the corresponding penetration depths are –1500, 300 and 700 mm. It follows that for equal surface cooling and equal fluences, the most superficial heating will occur with the 1450 nm laser, followed by the 1540 and 1320 nm lasers. The MIR spectral subset has become the mainstay for fractional non-ablative technologies. 7. Far infrared systems: The major lasers are the CO2, Erbium YAG and Erbium:YSGG (chromium:yttrium-scandium-gallium-garnet) lasers. Overall, the ratio of ablation to heating is much higher with the erbium YAG laser. However, one can enhance the thermal effects of the Er:YAG laser by extending the pulse or increasing the repetition rate and likewise one can decrease residual thermal damage (RTD) of the CO2 laser by decreasing pw (pulse width). Details of the two lasers are given in the chapter on ablative lasers.

Laser-tissue interactions The actual laser interaction is characterized by a dissipation of energy though an ideal situation is characterized by a direct straight line transfer of energy (z) (Fig. 1.6). When photons strike the surface of the tissue, because of the refractive index change, a portion (4–10%) of the photons are reflected

Fig. 1.6: Laser tissue interaction. Ideal laser penetration is a straight line (z) which is not normally seen as the skin is not an optical window

12  Lasers in Dermatological Practice

according to the angle of incidence. Photons penetrating the surface initially are refracted, obeying the law of Snellius, which states that photons entering a medium with a higher refractive index are refracted towards the vertical axis to the surface. Of all the different interactions, the most important is absorption or scattering.

Absorption The coefficient μa (cm-1) characterizes the absorption. The inverse, Ia, defines the penetration depth (mean free path) into the absorbing medium and is typically given as cm–1. The absorption coefficient is chromophore and wavelength-dependent. Absorbing molecular components of the tissue are porphyrin, hemoglobin, melanin, flavin, retinol, nuclear acids, deoxyribonucleic acid (DNA)/ribonucleic acid (RNA) and reduced nicotinamide adenine dinucleotide. The absorption spectra of different chromophores of biological tissue and water are plotted in Figure 1.1 while the penetration is shown in Figure 1.5.

Chromophores Blood, water and melanin are the main absorbing components in the tissue (Fig. 1.1). Therefore, dye lasers and diode lasers effectively interact with blood, the alexandrite laser with melanin and MIR lasers with the water content of the tissue. Hemoglobin: There is a large HgbO (oxyhemoglobin) peak at 415 nm, followed by two smaller peaks at 540 and 577 nm. An even smaller peak is at 940 nm. For deoxyhemoglobin (Hgb), the peaks are at 430 nm and 555 nm. The discrete peaks of hemoglobin absorption allow for selective vessel heating. Although the 410 nm peak achieves the greatest theoretical vascular to pigment damage ratio among the other peaks, scattering is too strong for violet light to be a viable option for vascular applications. Melanin: Most pigmented lesions result from excessive melanin in the epidermis. By choosing almost any wavelength (< 800 nm), one can pre­ ferentially heat epidermal melanin. Shorter wavelengths will create very high superficial epidermal temperatures, whereas longer wavelengths tend to bypass epidermal melanin (i.e. 1,064 nm). Fat: Fat shows strong absorption at 1,200 and 1,700 nm. Although the ratios of fat to water absorption are small, the small differences are exploited with the proper choice of parameters. 1,200 nm might represent the best choice due to decreased overall water absorption and therefore, increased penetration. Sebum is similar to fat but also is comprised of wax esters and squalene. Carbon: Carbon is a product of prolonged skin heating.

Basics of Laser-Tissue Interactions  13

Once carbon is formed at the skin surface, the skin becomes “opaque” to most laser wavelengths (that is, most energy will be absorbed very superficially. It follows that the dynamics of surface heating changes immediately once carbon is formed. This can be used creatively as an advantage. For example, one can convert a deeply penetrating laser to one that would only affect the surface by using a carbon dye. This has been accomplished with a laser peel using a Q-switched Nd:YAG laser, though is is not commonly used now. Collagen: Dry collagen has absorption peaks near 6 and 7 mm. With a free electron laser operating at these wavelengths, collagen can be directly heated.

Scattering The scattering behavior of biological tissue is important because it determines the volume distribution of light intensity in the tissue. This is the primary step for tissue interaction, which is followed by absorption and heat generation. Scattering of a photon is accompanied by a change in the propagation direction without loss of energy. Scattering leads to an increase in the light intensity directly below the tissue surface is enhanced by a factor of 2–4 as compared with the intensity of the incident beam. The increased fluence rate is caused by scattered photons overlapping with the incident photons. Another observation is that due to the scattering effect, the penetration depth depends on the irradiated area.

Practical Implications It has been shown that the light intensity directly below the tissue surface is enhanced by a factor of 2–4 as compared with the intensity of the incident beam. The increased fluence rate is caused by scattered photons overlapping with the incident photons. Because of the scattering effect, the penetration depth depends on the irradiated area. Thus, the penetration depth will double if for the same irradiance, the beam diameter increases from 1 mm to 5 mm. Thus for treating port wine stains or for hair removal, 10 mm to 15 mm spot diameters of the laser are recommended as it increases the depth of the laser beam. In tattoos and nevus of Ota in case there is inadequate response , it is wise to increase the diameter of the probe to increase the depth.

Reaction Mechanisms The first systematic presentation of the reaction mechanisms of lasers with tissue was by Boulnois and is depicted in the Figure 1.7. This highlights the different tissue effects and thus smaller the pulse duration of the interaction more the energy. Thus the Q-switched lasers like Nd:YAG can generate photodisruptive fluencies due to the short time of impact. The various tissue reactions include, Nonthermal reaction, chemical reactions, thermal reactions (based on relaxation time), tissue ablation or photodisruption.

14  Lasers in Dermatological Practice

Once the local subsurface energy density has been determined, heat generation can be predicted by energy balance (conservation of energy), pulse duration, thermal relaxation time and the wavelength specific absorption for that target. We will focus largely on the interactions relevant to commonly used medical lasers.

1. Photothermal Reactions Photothermal effects (1 ms–100 s; 1–106 W/cm2; Fig. 1.7) The energy of the laser irradiation is transferred into heat due to the absorption of the photons by tissue components, DNA/RNA, chromophores, proteins, enzymes and water. According to the degree of heating, stepwise and selective thermal damage can be achieved: ¾¾ 42–45°C: Beginning of hyperthermia, conformational changes and shrinkage of collagen; ¾¾ 50°C: Reduction of enzymatic activity; ¾¾ 60°C: Denaturation of proteins, coagulation of the collagens, membrane permeabilization; ¾¾ 100°C: Tissue drying and formation of vacuoles; ¾¾ >100°C: Beginning of vaporization and tissue carbonization; ¾¾ 300–1,000°C: Thermoablation of tissue, photoablation and disruption.

Fig. 1.7: A figurative depiction of the plot of laser tissue interaction

Basics of Laser-Tissue Interactions  15

Thermal diffusion is responsible for heat flow into the tissue. If the exposure time with a laser pulse, tp, is short compared to the diffusion time, td, then we have “thermal confinement” and the pulse energy is converted into heat. Thermal diffusion and the extent of tissue necrosis are related. With low laser power and long irradiation time, thermal necrosis is large. Shortening the laser application time reduces the time for thermal diffusion and the zone of necrosis becomes smaller. Minimum thermal necrosis is reached when the irradiation time is equal to the thermal diffusion time or thermal relaxation time. This is demonstrated by the laser interactions with pulsed CO2 lasers (Fig. 1.8). Thermal damage of the tissue is described by the Arrhenius rate equation (Fig. 1.9). The consequence of this equation is that the threshold for tissue damage depends on the laser power and the application time. This threshold can be reached with high laser power in a very short time, resulting in a higher temperature or with low power but long irradiation, where the threshold is reached with lower temperature.

2. Tissue Ablation The preconditions for tissue ablation are high absorption and very short laser pulses. Analogous to the thermal confinement, one can define a “stress confinement” when tissue is heated up so fast that the pulse duration is

Fig. 1.8: Example of the effect of pulse duration on tissue effect. (A) 3 J/cm2; 0.01 sec (whitening); (B) 3 J/cm2; 0.40 sec (coagulation); (C) 9 J/cm2; 0.50 (cogulation with ablation). Lower the irradiation time, lesser the coagulation the thermal necrosis

16  Lasers in Dermatological Practice

Fig 1.9: Time-temperature characteristic of tissue damage. Thus a 1s pulse reaches the threshold at 65°C, whereas a 10s pulse reaches the threshold at 57°C

shorter than the propagation time. When the stress wave with velocity “c” cannot leave the heated volume during the laser pulse, then it is removed with the ablation of the material and the surrounding tissue is not damaged. Only UV lasers (ArF excimer laser) and pulsed MIR lasers have such high tissue absorption that they are effective ablating lasers. Application: The threshold behavior of highly absorbed laser radiation, e.g., the erbium-doped yttrium-aluminium-garnet (Er:YAG) laser with a 2,940 nm wavelength, can be used to modulate the thickness of necrosis in soft tissue. Operation of the laser in normal ablation mode does not produce effective thermal necrosis; therefore, no coagulation can stop bleeding. The advantage is that the healing is fast with minimal scarring. However, for precise superficial surgical interventions, it would be helpful if the Er:YAG laser could be modulated to coagulate the tissue by a series of high-frequency sub-threshold laser pulses. The energy of such pulses is below the ablation threshold and therefore, is transferred into heat. The heat causes thermal necrosis. The thickness of the necrotic tissue layer can be modulated by the number of sub-threshold pulses.

3. Photodisruption (10 ps–100 ns:108–1010 W/cm2) Focused laser pulses in the nanosecond region (e.g. with a Q-switch neodymium (Nd):YAG laser), or with a picosecond or femtosecond durations (titanium (Ti) sapphire laser) develop power densities of 1012 W/cm² and more (Fig. 1.7). The electric field strength of this focused radiation is high enough to pull electrons out of the atoms, forming a plasma and producing an optical breakdown with shockwaves disrupting the tissue.

Basics of Laser-Tissue Interactions  17

Application A simple overview of laser tissue interactions as a function of time and depth is given in Figure 1.8. Lasers like Cw CO2 and Er:YAG classically have little thermal confinement. Ultrapulse CO2 lasers, some Er:YAG lasers, long pulse Nd:YAG and alex achieve thermal confinement , wherein the pulse duration is shorter than the thermal diffusion length or thermal relaxation time. The Q-switched lasers and PDL achieve stress confinement.

Effect of Cooling Surface cooling enhances efficacy and safety in skin laser surgery, especially for visible light technologies, (i.e., green-yellow light sources such as IPL, KTP laser, and PDL) that are popular in cutaneous laser surgery. This is also the wavelength range where epidermal damage is most likely. The epidermis is an innocent bystander in cutaneous laser applications where the intended targets, such as hair follicles or blood vessels, are located in the dermis. Specifically, absorption of light by epidermal melanin causes skin surface heating. The first goal is of surface cooling is preservation of the epidermis. The second and related goal of surface cooling permits higher fluences to the intended target (i.e., the hair bulb and/or bulge or a subsurface blood vessel). Another benefit of surface cooling is analgesia, as almost all cooling strategies will provide some pain relief.

4. Selective Photothermolysis (SPT) Selective photothermolysis offered a mathematically rigorous rationale for tissue-selective lasers. As described by Dr Anderson, extreme localized heating relies on: (1) A wavelength that reaches and is preferentially absorbed by the desired target structures; (2) An exposure duration less than or equal to the time necessary for cooling of the target structures; and (3) sufficient energy to damage the target. The heterogeneity of the skin allows for selective injury in microscopic targets.

Thermal Relaxation Time and Pulse Duration The thermal relaxation time (t) is the interval necessary for a target to cool to a certain percentage of its peak temperature. Given that one goal of treatment is the precise control of thermal energy, the pulse duration of laser irradiation is just as important as optical and tissue factors. One way to maximize the spatial confinement of heat is to use a laser with a pulse duration on the order of the thermal relaxation time (TRT) of the target chromophore (Fig. 1.10). TRT is defined as the time required for the heat generated by the absorbed light energy within the target chromophore to cool to half of the original value immediately after the laser pulse. During a lengthy laser exposure, most of

18  Lasers in Dermatological Practice

Fig. 1.10: Relation of pulse duration (p) and TRT (thermal relaxation time). p = TRT, heat is confined to the vessel, p > TRT, there is dissipation energy outside the vessel

the heat produced diffuses away despite its origin in the target structure. The target does not become appreciably warmer than its surroundings because the absorbed energy is invested almost uniformly in heating of the tissue during exposure. As a result, longer pulse durations offer a more generalized heating and therefore, less spatial selectivity resulting in nonspecific thermal damage to adjacent structures regardless of how carefully one has chosen a wavelength (Fig. 1.10). However, if the laser pulse is suitably brief, its energy is invested in the target chromophore before much heat is lost by thermal diffusion out of the exposure field (Fig. 1.10). A transient maximum temperature differential between the target and adjacent structures is then achieved. Shorter pulse durations confine the laser energy to progressively smaller targets with more spatial selectivity. The transition from specific to nonspecific thermal damage occurs as the laser exposure equals and then exceeds TRT. When defining thermal relaxation time, the target size and geometry are important (Box 1.1). For most targets, a simple rule can be used: The thermal relaxation time in seconds is about equal to the square of the target dimension in millimeters. Thus a 0.5 mm melanosome (5 × 10-4 mm) should cool in about 25 × 10-8 s, or 250 ns, whereas a 0.1 mm PWS vessel should cool in about 10–2 s, or 10 ms. This provides an approximate pulse width for varying degrees of thermal confinement. The often used term “thermal relaxation time of the skin” is meaningful only when used for specific wavelengths (or specific skin structures, i.e., the epidermis). With a ubiquitous absorber such as tissue water, it should be considered within the context of the laser source. For example, if one uses

Basics of Laser-Tissue Interactions  19 Box 1.1

TRT of potential targets used in dermatology

Melanosome (0.5 μm)

0.25 μs

Melanocyte (7μm)

1 μs

Nevus cell (10 μm)

0.1 ms

Collection of nerves cells (100 μm)

10 ms

Epidermis (100–200 μm) (dermoepidermal junction 10 μm)

10 ms

Erythrocyte

2 μs

Hair follicle (200 μm )

40 ms

Vessel (0.1 mm diameter)

10 ms

Vessel (0.8 mm diameter)

300 ms

Vessel (0.1 mm diameter)

10 ms

Tattoo (0.5–100 μm)

20 ns–3 ms

the 1,540 nm laser, the entire epidermis and large portions of the dermis are heated and the TRT is on the order of seconds, because the thickness is several hundred millimeters. So even though TRT of the epidermis is about 10 ms based on its thickness, a thicker slab of skin is heated at 1,540 nm, the epidermis will take several seconds to cool because there is no temperature gradient between it and that of the dermis. A summary of the TRT of major target tissues is given in Box 1.1.

Application With a very short pulsewidths (pw), lasers vaporize targets. For example, in treating blood vessels, rapid heating results in acute vessel wall damage and petechial hemorrhage (with Q-switched 532 nm). With intermediate length pulses (0.1–1.5 ms), one can gently heat targets without immediate rupture of the vessels. But intravascular thrombosis can create purpura and delayed hemorrhage. With longer pulses (6–100 ms), the ratio of contraction to thrombosis increases and side effects are less likely. Too long pulses with very small targets can create two problems. With highly absorbing targets, (i.e., tattoo inks), the heat generation is so great and long-lived that significant diffusion occurs to the surrounding dermis. On the other hand, using a long pulse YAG for a nevus of Ota results in an insufficient temperature rise as the pigmented nevus cells cool off too fast during the delivery of the pulses (also melanin absorption is much weaker than black ink).

Selective Photothermolysis of Tattoos Amorphous carbon, graphite, India ink and organometallic dyes, typically found in dark blue-black amateur and professional tattoos, have a broad absorption in the visible and near-infrared portions of the spectrum. At visible

20  Lasers in Dermatological Practice

wavelengths longer than 600 nm, hemoglobin and melanin light absorption is minimized and tattoo dyes can be targeted selectively. The pigment granules characteristically found in tattoos have diameters of 0.5–100 mm, which correspond to TRT of 20 ns to 3 ms. With the development of the Q-switched ruby (694 nm), alexandrite (755 nm), and Nd:YAG (1.06 mm) lasers, tattoo removal without scarring can be achieved. The frequency-doubled, Q-switched Nd:YAG laser (KTP laser) emits at a wavelength of 532 nm, which provides improved removal of red dye. Recently picosecond lasers have been used for tattoos.

Selective Photothermolysis of Pigmented Lesions Pigmented lesions can be divided in to epidermal and dermal. Although highest in the ultraviolet portion of the spectrum, melanin absorption is also significant in the visible and near-infrared wavelengths. The diameters of individual melanosomes (0.5–1.0 μm) and melanocytes (7 μm) correspond to TRT of 20–1,000 ns. Therefore, Q-switched green, red, and near-infrared wavelengths have been utilized for this indication. Though Q-switched lasers are used most commonly the gentle heating by the millisecond laser can also treat epidermal disorders. With longer pulses (ms), the dermal melanocyte does not become hot enough to achieve pigment reduction, thus ensuring selective epidermal damage.

Selective Photothermolysis and Laser Assisted Hair Removal The human hair follicle is a complex structure derived from both epidermal and dermal components. The target chromophores, primarily melanin-rich hair shafts, are located deep in human skin (bulge around 1.5 mm and bulb at 2–7 mm). At this depth, only red and near-infrared wavelengths are useful (690–900 nm). The follicular structure responsible for regeneration has not been conclusively identified and therefore, current systems target the entire follicle. As a result, long pulse widths on the order of milliseconds and high fluences capable of heating large volumes of tissue are required. Milliseconddomain ruby, alexandrite, diode and Nd:YAG lasers using high light doses can produce selective injury to human hair follicles resulting in prolonged growth delay and in some cases, permanent hair loss after a single treatment.

Selective Photothermolysis of Cutaneous Blood Vessels The pulsed dye lasers at 577–595 nm wavelengths well absorbed by the targeted hemoglobin molecule relative to other optically absorbing structures, cause selective thermal damage to dermal blood vessels while minimizing epidermal melanin absorption. Furthermore, because the TRT for cutaneous blood vessels varies between 10–300 ms a variable pulse duration is required for optimal results.

Basics of Laser-Tissue Interactions  21

But there are numerous variations in pulse duration and absorption of various chromophores (bloodless dermis, oxyhemoglobin and deoxyhemoglobin) that can complicate this simplistic interpretation.

Practical Clinical Applications There are numerous clinical applications that have been given in the text above and the chapters that follow. Two examples are given below: 1. The geometry (and therefore the microscopic characteristics) of lesions is important. For example, in the treatment for a nevus versus a lentigo, the nevus is composed of melanocytes in aggregates as (collectively of a size of 100 μm in diameter) whereas the lentigo is a mere sheet of melanocytes some 10 μm thick. So the TRT of the nevus cell is about 10 ms while that of the lentigo is about 0.1 ms (Box 1.1). Thus, in treating nevus with a long pulsed alexandrite laser with a high fluence, the TRT will approach a second. From the above equation, it follows that thermal confinement will be high, and the peak temperature will rise accordingly. More importantly, the thick slab of melanocytes will take long to cool, such that there will be considerable heat diffusion away from the target. On the other hand, the lentigo represents a slab only tens of microns thick; there will be heat diffusion during the long pulse and rapid cooling after the pulse. Thus, with ms-domain fluences, the nevus case might result in scarring and a lighter lentigo might not become hot enough for clearance. If one applies ns pulses to the two lesion types, the lentigo shows a good response with possibly complete clearing, whereas the nevus will require multiple sessions, as each laser application will result in heat confined to the most superficial part of the lesion. Conversely a microsecond laser might work for nevi. 2. Spot diameter: In general, the spot size should be 3–4 X > d (target diameter), as larger spots make it more likely that photons will be scattered back into the incident collimated beam. Photons scattered out of the beam are essentially wasted. Larger beams (with the same surface fluence as smaller beams) create deeper subsurface cylinders of injury because there is less surface versus volume for photons to escape. Basically, for small beams (narrow), scattered photons are carried out of the beam path after only a few scattering events. Thus, as a thumb rule, larger the spot, more the dermal/epidermal damage ratio but also higher is the epidermal damage thus the fluence should be reduced. For shallow penetrating lasers such as CO2 and erbium where the d 30) and to avoid sun exposure before, during and immediately after their

230  Lasers in Dermatological Practice

treatments. There is no evidence that treating with topical hydroquinone for 1–2 months prior to non-ablative fractional resurfacing decreases the risk of postinflammatory pigmentation in individuals with darker skin types (type IV–VI). There is no scientific evidence that topical retinoids need to be discontinued prior to treatment in those with sensitive skin. We, though prefer using topical retinoids in cases of acne scarring and a non HQ/Steroid based, depigmenting cream in our patients (MelaglowTM/Clearz PlusTM). 2. Antiviral prophylaxis should be given only if there is history of herpes labialis. 3. Anesthesia: There are two options, either using prilocaine based creams or tetracaine based creams. Anesthetic agents with tetracaine induce significant erythema leading to patient dissatisfaction. Thus another option is to use 30% lidocaine. 4. Baseline photograph: In case topical anesthesia is used , it must be noted that some patients have a ‘blanched appearance’ thus making photographic evaluation difficult. Thus a photograph should be taken before applying the anesthesia.

INTRAOPERATIVE 1. Ensure that the laser handpiece is applied perpendicular to the skin. 2. Scanning Hand Piece: While using the Fraxel systems (Solta Medical, Hayward, CA) the protocol is eight passes when treating acne scars, rhytides, and photoaging of the face. A double-pass, 50% overlap technique is used. One linear pass is delivered, the handpiece is brought to a complete stop, lifted, repositioned, and then returned along the same path for a second pass. The handpiece is then moved laterally by 50% and the technique is repeated until the treatment area is completed. As a result, each area is treated with four passes. For the next four passes, the passes are given perpendicular to the first treatment to ensure complete and even laser coverage. 3. Stamping hand piece: For stamping handpieces, the fractionated energy is delivered according to the tip size. The Lux system (Palomar Medical Technologies Inc., Burlington, MA) and the Acepelion Er:YAG is example. Here three to four passes are generally delivered with a 50% overlap in both directions. The handpiece should be lifted off the skin between each pulse, and pulse-stacking is not recommended. The number of passes and treatment parameters vary with the different machines and is discussed in the chapter of fractional lasers.

Fractional Photothermolysis  231

POSTOPERATIVE ¾¾ Erythema develops immediately afterwards in all treated patients and typically resolves in 3 days. ¾¾ Use of non-comedogenic moisturizers is recommended (Sebamed clear Gel, Cetaphil cream). ¾¾ Patients are advised to wear sun protection for several weeks after their treatment to reduce the risk of hyperpigmentation. A useful option is to use a depigmenting cream with a sunscreen ¾¾ In Indian skin, it is advisable to start a lightening cream after 7 days, though others wait till 21 days by which time PIH appears. A nonsteroidal non-HQ based cream is preferred (MelaglowTM, Clearz PlusTM).

PITFALLS/PEARLS 1. The response to most fractional lasers is curvilinear and delayed. This is for the simple reason that scar remodeling takes 6-9 months.Thus giving 8 sittings gives better results. The first two treatments yield very little visible improvement, the next two a bit more, and the final two show the greatest degree of change. Sometimes in patients with bad scarring an additional two treatments help but it is advisable better to wait for 6 months to see the maximum improvement from the first six before deciding. This has another important implication and that is unnecessary procedures like CROSS, subcision, dermaroller and ascribing improvement to them can wait for at least 6 months after laser therapy! This is as they are credited with the improvement which the laser would have induced if enough time had elapsed post surgery. A simple protocol is, fractional laser (6-8 sessions) followed by 6 months of follow up which should be followed by surgical procedures. Thus an average of one year may be required for a acne scar patient. 2. Patients with significant photodamage, sagging, and deep rhytides are not a candidate for fractional lasers as this requires other techniques like fillers and botox, the combination of which with lasers is strictly off label. 3. To minimize the risk of systemic toxicity from the topical anesthetics, areas no greater than 300–400 cm2 should be treated during each session. In case the patient complains of agitation , anxiety, nausea and perioral paresthesias, it indicates toxicity. A infusion of normal saline is helpful. To avoid this problem, topical anesthesia application should be limited to no more than 1 hour. 4. In general, in Indian skin post-inflammatory pigmentation is less common using lower density settings, fewer passes, and longer treatment intervals.

232  Lasers in Dermatological Practice

5. Decrease the MTZ areal density if higher energies are applied per MTZ to keep the areal fraction of damaged skin surface constant.

BIBLIOGRAPHY 1. Bagatin E, dos Santos Guadanhim LR, Yarak S, Kamamoto CS, de Almeida FA. Dermabrasion for acne scars during treatment with oral isotretinoin. Dermatol Surg. 2010;36(4):483-9. 2. Picosse FR, Yarak S, Cabral NC, Bagatin E. Early chemabrasion for acne scars after treatment with oral isotretinoin. Dermatol Surg. 2012;38(9):1521-6.doi: 10.1111/j.1524-4725.2012.02460.x.

Fractional Photothermolysis  233

ATLAS

Fig. 1: Overlapping of fractional laser to increase the ‘aspect ratio’ and density (Er:YAG Ascepelion 90 J/cm2). This technique can be used to target deep ice pick scars

Fig. 2: Post laser crusting that tends to fall-of in 5–7 days. The laser used was the Fractional Er:YAG (Dermablate, Ascepelion)

Fig. 3: A topography of a patient with acne scar, ice pick scar (yellow circle), boxcar scar (red circle) and rolling scar (blue circle)

234  Lasers in Dermatological Practice

Fig. 4: Follow-up photograph of the patient after 5 sessions of fractional Er:YAG with substantial amelioration of all types of scars

Fig. 5: Intense erythema and edema immediately after using the Er:Glass. This is as the absorption spectrum for water of the Er:Glass is less than that of Er:YAG and CO2 leading to more tissue reaction

Fig. 6: A male patient with predominantly ice pick and boxcar scars. Plan: Fractional Er:YAG (162 J/cm2; 6 sessions). The ‘aspect ratio’ of the laser was altered to increase the energy in the areas with deep scars

Fractional Photothermolysis  235

Fig. 7: At 6 months follow-up there is a improvement of most of the scars except the deep boxcar scars which remodel with time, thus unnecessary surgical/TCA is unwarranted

Fig. 8: A case with predominantly rolling scars. Plan: Fractional Er:YAG (126 J/cm2; 6 sessions)

Fig. 9: Marked improvement in rolling scars which respond to most fractional lasers

Chapter

5

Vascular Lasers Sujay Khandpur, Banwari Jangid

Background Cutaneous vascular lesions, especially those occurring on the face, produce devastating cosmetic impact and psychological distress, besides being associated with pain, bleeding, ulceration, infection and obstruction of vital functions. This necessitates prompt treatment with good cosmetic results. Earlier, vascular lesions were treated with radiation, cryotherapy, excision and grafting, and camouflage, with unsatisfactory results and poor aesthetic outcomes. Bleeding, scarring and pyogenic granuloma formation were the common complications. The introduction of lasers with the immense convenience of being used in an outpatient setting, has allowed for easier patient access with more reliable and cosmetically pleasing results. The best therapy consists of use of the most appropriate laser that produces significant clearance of the lesion in the fewest treatment sessions with the least morbidity. Laser treatment for cutaneous vascular lesions was initiated by Dr Leon Goldman in 1963 at the Children’s Hospital Research Foundation in Cincinnati, Ohio, with the treatment of port-wine stains (PWS) and cavernous hemangiomas using ruby, neodymium:yttrium-aluminum-garnet (Nd:YAG), and argon lasers. The treatment of vascular lesions is one of the most commonly requested cutaneous laser procedures. Since the introduction of the argon laser, a variety of laser and light sources are being used for the treatment of vascular lesions. These include visible and infrared lasers, as well as broadband light sources. The chromophore for treating vascular lesions is hemoglobin, whose absorption maximum lies at 418 nm, 542 nm, and 577 nm. Therefore, lasers with wavelengths between 488 nm and 600 nm are useful for the treatment of vascular lesions.

Theory of Selective Photothermolysis The theory of selective photothermolysis was developed by Anderson and Parish (Anderson RR et al.). They proposed that, to limit thermal damage to the intended target, the pulse duration of laser must be shorter than the thermal relaxation

Vascular Lasers  237

time of the target tissue. The thermal relaxation time of tissue is defined as the time taken by target tissue to transfer its 50% heat to the surrounding tissue through thermal diffusion. The thermal relaxation time of vessels with diameter of 10 µm to 50 µm is 0.048 ms to 1.2 ms (Anderson RR et al.). Typical natural chromophores in skin include water, melanin, hemoglobin, protein, lipid, etc. Artificial chromophores that can be used include dyes, ink, carbon particles, etc. In vascular lesions, the targeted structure is oxyhemoglobin within blood vessels. When hemoglobin is heated, it also heats up and destroys the endothelial cells of blood vessel walls.

Lasers Commonly Used to Treat Vascular Lesions Flashlamp-pumped Pulsed Dye Lasers Flashlamp-pumped Pulsed Dye Lasers (PDL) were first successfully used by Tan et al. in 1989 for PWSs. PDL was the first laser developed based on the principle of selective photothermolysis. The flashlamp-pumped PDL has as its active medium an organic dye energized by a short pulse of light from a flashlamp. PDL emits a pulsed beam of yellow light at 585 nm to 600 nm powered by flash lamp. Majority of the PDLs have an integrated cooling system, and with maximal achievable energy fluence of 20 J/cm2 which targets oxidized hemoglobin in superficial blood vessels. The brief pulse duration of 300 µs to 500 µs can cause vascular rupture. After treatment, there are histologic findings of agglutinated red blood cells, fibrin, and platelet thrombi within the vessels of the papillary and superficial reticular dermis (average depth of 1.2 mm) with little or no damage to the surrounding tissue.

Neodymium:Yttrium-Aluminum-Garnet (Nd:YAG) Laser The 1,064 nm wavelength has been used for various pigmentary diseases and vascular dermatoses. With the advent of lasers capable of achieving longer pulse durations and longer wavelengths, deeper (depth of 5 mm to 6 mm) and larger caliber vessels can be treated more effectively with fewer treatment sessions and less purpura. The absorption coefficient of blood at 1,064 nm is 0.4/mm, which is much higher than that of the surrounding dermis (0.05/mm) at the same wavelength. This difference in absorption coefficients provides treatment selectivity of deeper blood vessels. Lower absolute values of blood absorption at 1,064 nm may be compensated by increasing the fluence. The increase in fluence does not necessarily damage the epidermis, because the absolute absorption of melanin is lower at 1,064 nm.

Potassium Titanyl Phosphate (KTP) Laser KTP with a wavelength of 532 nm is an alternative laser for superficial cutaneous vascular lesions. This laser emits green light and produces pulse durations ranging from 1 to 100 ms. These longer pulse durations gradually

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heat the blood vessel, without vessel wall rupture and subsequent purpura. Side-effects frequently seen with the KTP are edema, crusting and atrophic scarring (particularly using smaller spot sizes to treat nasal telangiectasias). Because of the shorter wavelength, there is greater absorption by epidermal melanin in darker skin types and this limits the laser’s use in Fitzpatrick skin types III-VI.

Argon Lasers The development of the argon laser with wavelengths between 488 nm and 577 nm allowed successful treatment of vascular lesions. However, it carries the disadvantage of damaging the surrounding tissue including epidermis, which produces depigmentation, epidermal atrophy and scarring.

Intense Pulsed Noncoherent Light Intense pulsed light (IPL) systems generate pulsed, polychromatic, noncoherent high-intensity light in a broad wavelength spectrum, in the range of 500 nm to 1400 nm with the use of flashlamps and cut-off filters. Depending on the cut-off filter used, treatment of superficial or deeper vascular lesions such as facial telangiectasias, diffuse redness, poikiloderma of Civatte, portwine stains, hemangiomas and leg veins can be facilitated.

Indications for Vascular lasers ¾¾ Congential vascular lesions • Port-wine stains (nevus flammeus) • Hemangioma ¾¾ Acquired vascular alterations • Rosacea • Facial telangiectasia • Telangiectasias associated with other conditions • Poikiloderma of Civatte • Angiofibroma • Blue rubber bleb nevus syndrome • Campbell de Morgan angiomas • Cutaneous lesions of Kaposi sarcoma • Pyogenic granuloma • Leg veins • Morbus Ossler (hereditary hemorrhagic telangiectasia) • Nevus araneus (spider angioma) • Senile angioma (ruby dot) • Venous angiomas • Venous lake

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¾¾ Other skin diseases with vascular alternations • Acne • Early immature striae distensae • Inflammatory linear verrucous epidermal nevus • Psoriasis • Red or hypertrophic scars • Viral warts • Xanthelasma palpebrarum.

Port-wine stain Port-wine stains (PWSs) are the commonest cutaneous vascular malformations, involving the postcapillary venules, and affect 3 children per 1,000 live births with no gender predilection. It is believed that PWSs develop within the first 2 to 8 weeks of gestation (Schneider BV et al.), appear as flat and pink-red to violaceous patches and later turn dark purple in color. They are present for life and have no tendency toward involution. The subsequent hypertrophy of underlying bone and soft tissue further disfigures the facial features of many patients. PWSs may be localized, segmental, diffuse or extensive and occur anywhere on the body, but commonly involve the head and neck region, classically following the trigeminal nerve distribution on the face. The cause of PWS still remains obscure. It is characterized by ectatic papillary dermal capillaries and postcapillary venules in the papillary and upper reticular dermis, with some evidence of increased vessel density but no proliferation of vessels. The most likely hypothesis for the development of PWS is the deficiency or absence of perivascular nervous tissue in lesional skin, suggesting that inadequate innervation may in part be responsible for decreased vascular tone causing permanent vascular dilatation (Smoller BR et al.). Vascular endothelial growth factor (VEGF) and VEGF-R2 expression are significantly increased in capillary malformation skin tissue, suggesting that VEGF and VEGF-R could contribute to the pathogenesis of capillary malformations by inducing vessel proliferation (Vural E et al.). PWSs are associated with syndromes such as Sturge-Weber syndrome, KlippelTrenaunay syndrome, Cobb syndrome and Proteus syndrome.

Infantile hemangioma Hemangiomas affect up to 4% to 10% of infants, with 60% occurring on the head and neck, 25% on the trunk, and 15% on the extremities (Finn MC et al.). Eighty percent of hemangiomas are single, well-circumscribed lesions, 0.5 cm to 5.0 cm in diameter, while the rest are multiple, cutaneous and visceral lesions (Mulliken JB).

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Infantile hemangiomas present at birth or in neonatal period, as small macule or patch of erythema which later rapidly proliferate, then stabilize, and slowly involute. The course of individual hemangiomas is heterogeneous, making it difficult to predict outcomes reliably. Approximately 20% of hemangiomas may develop complications in form of ulceration, bleeding, infection, functional impairment with visual, feeding and respiratory difficulties, which may require active intervention. Fifty percent of infantile hemangiomas completely involute by age of 5 years and 90% by 9 years of age. The remainder may take additional 2–4 years to complete the process (Bowers RE et al). They can be classified as superficial, deep and mixed hemangiomas. Superficial lesions are raised and bright red, and upon regression, leave a flaccid, pedunculated, waxy, yellow-colored skin. Deeper dermal lesions appear as bluish subcutaneous nodules with overlying skin having a fine network of telangiectasia and resolve leaving smooth skin surface with overlying telangiectasia. According to a study, the lesions that involuted by age 6 years had 38% residual evidence and hemangiomas that completely involuted after age 6 years exhibited cutaneous residua in 80% instances including scar formation, telangiectasia, or redundant skin (Finn MC et al.). Hence it has been shown that infantile hemangiomas that take longer to involute have a higher incidence of residual changes.

Common acquired vascular lesions Rosacea Rosacea is a chronic disorder involving the mid facial region and occasionally the neck, scalp and eyes. It usually occurs between 20 and 50 years, with female preponderance, however, men more frequently progress to the end stages of severe rosacea. Clinically, rosacea can be classified into four subtypes- erythematotelangiectatic, papulopustular, phymatous and ocular rosacea, with one variant, granulomatous rosacea.

Rosacea Staging Stage I II III

Symptoms and Signs Pre-rosacea Frequent flushing/blushing Easy irritation and erythema of facial skin Vascular stage Transitory erythema of midfacial areas Early telangiectasias Deeper facial erythema Increased telangiectasias Papule and pustule formation

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IV Tissue hyperplasia Rhinophyma Possible ocular inflammation The first stage of rosacea is merely a vascular hyper-reactivity or tendency for the central face to redden easily. The early stage of rocasea is difficult to treat, except for avoiding the triggering factors. Second stage of rosacea is characterized by persistent and progressive erythema and ocular symptoms. Papules, pustules and telangiectasias develop when the disease progresses to third stage, finally, the fourth stage is characterized by rhinophyma, in which soft tissue hypertrophy of nose occurs producing a red, bulbous nose. Erythematotelangiectatic rosacea have been successfully treated with PDL. In addition to PDL, other lasers, including potassium titanyl phosphate, 532 nm Nd:YAG, 1064 nm Nd:YAG, argon, copper-bromide, and intense pulsed light have been used in treatment of facial telangiectasia.

Other Facial Telangiectasia Besides rosacea, facial telangiectasias are seen in hereditary hemorrhagic telangiectasia, collagen vascular diseases, idiopathic generalized telangiectasia and unilateral nevoid telangiectasia.

Poikiloderma of Civatte Poikilodermatous skin is characterized by atrophy, hyper- and hypo­ pigmentation, and telangiectasia. Poikiloderma of Civatte occurs on the sides of neck, more commonly in middle-aged women with a fair complexion. Several lasers have been tried including argon, potassium titanyl phosphate (KTP), pulsed dye laser and intense pulsed light devices with variable results (Goldman et al.; Oldbricht et al.; Batta K et al.; Wheel and RG et al.; Clark RE et al.). Multiple sessions are usually necessary to obtain optimal clearance.

Venous Lakes Venous lake is usually a solitary, soft, compressible, dark blue to violaceous, 0.2 cm to 1 cm sized papule caused by dilatation of venules. These are commonly found on sun-exposed surfaces of the vermilion border of lip, face and ears. Lesions generally occur in the elderly. Venous lakes have clinical importance because of their mimicry to malignant lesions, such as melanoma and pigmented basal cell carcinoma. Various surgical and laser modalities have been tried for venous lakes.

Varicose veins Varicose veins are dilated, tortuous, palpable subcutaneous veins, generally larger than 3 mm in diameter, most commonly found in the legs. Visible varicose veins in the lower limbs are estimated to affect at least a third of the population. According to a study, 29% of those who had visible varicose veins

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without complications progressed to serious venous disease after 6.6 years (Rabe E). In another study, approximately 3–6% of people developed varicose ulcer in their life (Nelzen O).

Step by Step Approach Patient Selection Appropriate treatment of vascular lesions begins with a correct diagnosis. A misdiagnosis can lead to ineffective and potentially harmful treatment. Proper patient selection is mandatory for good success rates. Patients presenting for treatment with vascular lasers are treated with the following goals: 1. Improving overall appearance, with an ideal target to clear the lesions without any complications 2. Improvement in functionality 3. Prevention of disfigurement 4. Avoiding aggressive procedures 5. Preventing or treating ulcerated lesions 6. Minimizing psychological distress.

Preoperative ¾¾ A written informed consent of the patient is taken ¾¾ Patients are scanned for unrealistic expectations. Doctor or staff should always explain about the procedure to the patient. Multiple laser treatments are usually necessary to remove a vascular lesion necessitating multiple sessions at regular intervals. Although laser treatment has fewer side-effects as compared to surgical procedure, there is a small risk of the following which needs to be explained to the patient: Hypopigmentation, hyperpigmentation, mottled discoloration, infection, pain, swelling, activation of herpes simplex infection, allergic reaction to local medications, atrophy or mild scarring, and lesion persistence despite treatment ¾¾ Baseline and subsequent pre-session photographs are taken ¾¾ Laser treatment is usually well-tolerated. Topical anesthetics (such as 2.5% lignocaine + 2.5% prilocaine) should be applied under occlusion for at least 45 minutes before the procedure to reduce local discomfort ¾¾ The area to be treated should be shaved in the morning of treatment and rinsed well. No hair removing creams or lotions should be used. No creams, lotions or sprays should be applied to the area ¾¾ The area being treated should be cleansed with mild soap and alcohol.

Intraoperative ¾¾ The correct laser parameters are chosen and recorded

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¾¾ Laser safety of the doctor and patient is ensured by wearing especially designed protective goggles during the procedure ¾¾ A test shot is given before procedure to check for any significant pain ¾¾ The patient is advised not to move his head or flinch with each pulse of light delivered as the machine makes a popping sound ¾¾ The laser is delivered concomitantly with cryogen cooling to prevent nonspecific thermal damage to surrounding tissue.

Postoperative ¾¾ Immediately after procedure, the patient is advised to apply cold compresses to the treated site ¾¾ A topical steroid-antibiotic cream is applied ¾¾ The patient is explained about immediate post-treatment appearance. After treatment, the area may be discolored (purpura) and swollen. Following this, a blister and/or crust may form which can last up to 7–14 days. To reduce swelling and discomfort, cool water compresses may be applied to the area. Do not apply ice directly to the treated area ¾¾ The rate of response to treatment is explained ¾¾ In case of pain and discomfort, acetaminophen is preferred over aspirin or ibuprofen during the healing phase (1 to 2 weeks) as this can increase bruising ¾¾ Showers are permitted but prolonged hot baths are not advised for 1–2 weeks. Patients are advised not to rub but dab the treated area with a towel because the area is extremely delicate while healing ¾¾ Make-up and moisturizers may be applied as usual if there is no blister/ ulceration. Otherwise, wait until the crusting has come off. If make-up is applied to cover up the bruising, do not use make-up remover or cleanse harshly while the skin is still healing as this may injure or abrade the treated area ¾¾ Avoid sunlight exposure to the treated areas. Use a sunscreen with SPF 30 or higher for several months following treatment to avoid prolonged redness or pigmentary changes ¾¾ Avoid swimming and contact sports while the skin is healing ¾¾ Post-treatment precautions: Patients should avoid: a. Exercise for three days after treatment b. Consumption of alcohol or any blood thinners for five days c. Taking hot showers or baths, use of hot tubs or saunas for five days ¾¾ The subsequent sessions should be undertaken at 6–8 weeks interval. Prior to the next session, thoroughly examine the treated site and compare with baseline photograph to look for improvement and sideeffects following previous therapy in order to decide the next laser parameter.

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Pearls and Pitfalls 1. Port-wine Stains PDL was specifically designed to treat small vessels found in childhood PWSs. Controversy exists about treating PWS in early versus late stage. However, there are certain advantages of early treatment: ¾¾ In early stage, the lesion is small in size so fewer spots and sessions are required ¾¾ Resolution is quick as compared to older lesions, so fewer treatments are required (Alster TS et al.) ¾¾ Early clearance produces less psychological effect on child (Lanigan SW). Morelli and Weston (Morelli JG et al.) demonstrated that early treatment of PWS gives better results. They proposed that therapy can be started as early as 7 to 14 days of age and three treatments may be undertaken before the infant reaches 6 months of age. They noted a 50% resolution with this protocol by the third treatment. In another study, Goldman et al. treated 43 children with 49 lesions of capillary malformation between ages of 2 weeks and 14 years. A total of 28 lesions treated in children under age 4 years had greater overall improvement with less treatment sessions as compared to those over age 4.5 years (Goldman MP et al.). Alster and Wilson reported 87% clearance rate in patients less than 2 years of age, 78% clearance in those aged 3 years to 8 years, and 73% clearance in patients 16 years and older. All these studies demonstrate a better treatment outcome in younger patients (Alster TS et al.). Nguyen CM et al. evaluated the predictors of improvement of PWS and proposed that younger patients with small PWS (less than 20 cm2) that are located over bony areas of the face, show greater response when compared to others (Nguyen CM et al.). The common starting parameters are fluence of 5.0–5.5 J/cm2, with increase by 0.5 J/cm2 with each subsequent treatment, using a 7 mm-diameter spot size. In our experience, 5 to 10 sessions are required to achieve significant improvement/clearance. Superficial lesions clear more quickly, with around four sessions, reaching a level of 95% clearance (Goldman MP et al.). When compared with adult PWS, in children, a lower fluence and larger spot size is recommended. Larger spot size prevents cobble stone appearance. With regard to the number of sittings required for complete or near complete clearance, Koster PHL et al. proposed a mathematical factor of 10% clearance with each session for the first five or six treatments. Additional treatments result in lesser therapeutic response so that 20 treatments are required to produce 90% clearance. Lesions present on the lateral side of forehead and cheeks, proximal part of arms and chest respond better as compared to central area of face and limbs (Alster TS et al.).

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Adverse events are usually temporary and include purpura and epidermal crusting. Purpura is more common with PDL compared to other lasers and IP lights. The most common long-term sequelae are pigmentary changes since melanin is a competitive chromophore with hemoglobin in patients with higher Fitzpatrick skin types. Other less common complications are ‘checkerboard’ pigmentation, hypopigmentation, atrophic and hypertrophic scarring and keloid formation. According to a study, discoloration and purpura were seen in almost all patients, crusting in 52%, and scaling or peeling in 19.6% cases (Ruiz-Esparza J et al.).

Factors Affecting Treatment Response ¾¾ Site of lesion—lesions over the face, and trunk respond better than legs (Alster TS et al.) ¾¾ Size of lesion—lesions larger than 20 cm2 respond poorer as compared to smaller lesions (Nguyen CM et al.) ¾¾ Color of lesion—dark red and purple PWS are less responsive than pink or red lesions. The purple color of lesion indirectly reflects the depth of lesion (Ruiz-Esparza J et al.). ¾¾ Skin types—fairer skin types respond better than dark skin (Sharma VK et al.; Ernest Tan et al.) ¾¾ Depth of lesion—lesions with deeper vessels respond poorly. PDL at 585 nm and 6 to 8 J/cm2 have been found to coagulate the vessels up to 0.65 mm (mean 0.37 mm). 585 nm dye is more effective in pink or red PWS whereas blue or dark red PWS respond well with 595 nm dyes (Figs 5.1 to 5.4). In our practice, for treating PWS with the 595 nm PDL, the laser parameters that we use are a spot size of 7 mm, starting fluence of 7–8 J/cm2 with increase up to 12 J/cm2 (for hypertrophic PWS) and pulse durations ranging from 0.45–6 ms. If the PWS are not responding to PDL: ¾¾ Use higher fluences, increase the spot size of the PDL ¾¾ Change from a 585 nm to a 595 nm wavelength (Chang CJ et al.; Greve B et al.) ¾¾ Increase the pulse duration from 0.45 ms to 1.5–20 ms (Greve B et al.) ¾¾ Perform multiple passes at the same session with variable pulse durations ¾¾ Combination of lasers: 595 nm and 1,064 nm laser, PDL and diode laser (Alster TS et al.).

Argon Laser in PWS Argon laser was the first to be used for vascular malformations. It is useful for treating hypertrophic nodules of very thick PWS (Dixon JA et al.).

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A

B

Figs 5.1A and B: (A) Pretreatment image of PWS over right face; (B) 80% clearance after 7 sessions of 595 nm PDL

A

B

Figs 5.2A and B: (A) Pretreatment image of PWS over left paranasal region; (B) 90% clearance after 10 sessions of 595 nm PDL

2. Lasers in Hemangiomas The argon laser has been effectively used to treat hemangiomas. The potential drawbacks of argon laser are its depth of penetration into the dermis (100 ms) may allow for long-term hair removal.

Fluence Optimum fluence or energy is such which would cause effective thermal destruction of the hair follicle melanin without causing any damage to the epidermis. This would be different for different individuals depending on the skin and hair type. The best way to decide this is to do a patch test with three different fluences and then deciding the right fluence depending on the skin response. This is the most important parameter responsible for longterm reduction achieved with lasers. Highest tolerable fluence gives better results by causing effective thermal destruction of hair follicle melanin in the dermis but heat damage to the epidermal melanin, which may result in adverse effects of burns, blistering, dyspigmentation and scarring, especially in dark skinned patients.

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Spot size A small spot size is useful for doing small areas like upper lips, side locks, etc. A larger spot size has better penetration and is more comfortable and quick for large body parts. Larger the spot size of the laser beam, deeper and more even is the penetration.

Skin cooling This is one aspect of lasers and light devices which is being constantly improved. Adequate skin cooling significantly increases the patient comfort, decreases the chances of burns and improves the results as higher energy levels can be delivered to the patient safely.

Cooling Mechanism Cooling can be obtained before, during, and after laser treatment (pre-, parallel level, and post-cooling) as contact cooling (cooled sapphire, metal or glass plates integrated into the handpiece, cooled gel layer); cold air ventilation; and dynamic cooling devices when pulsed cryogen spray is used as a cooling agent . The least effective type of cooling is the use of an aqueous cold gel, which passively extracts heat from the skin and then is not capable of further skin cooling. Alternatively, cooling with forced chilled air can provide cooling to the skin before, during, and after a laser pulse. Currently, most of the available LHR devices have a built-in skin cooling system, which consists of either contact cooling or dynamic cooling with a cryogen spray. Contact cooling, usually with a sapphire tip, provides skin cooling just before and during a laser pulse. It is most useful for treatments with longer pulse durations (>10 ms). Dynamic cooling with cryogen liquid spray pre-cools the skin with a millisecond spray of cryogen just before the laser pulse. A second spray can be delivered just after the laser pulse for post-cooling, but parallel cooling during the laser pulse is not possible as the cryogen spray interferes with the laser beam. Dynamic cooling is best suited for use with pulse durations shorter than 5 ms. The various method of cooling include: Cryogen sprays: These are more useful when working with low pulse width lasers. Chill tip cooling: This is now seen in majority of the lasers. The temperature of chill tip is 4 degrees before and after shot and 0 degree during the shot. This is a very practical and convenient means of pre- and post- and cooling during the session. Ice packs: These can be used for post-cooling while doing large body parts and also with the laser/light machines which don’t come with the option of chill-tip cooling. Using of ice packs can be very cumbersome at times and are at best adjunctive measure. Forced refrigerated air (Zimmer): This is now gaining popularity as means of cooling with all laser procedures including the laser hair reduction. It gives

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chilled air and can be used throughout the procedure to increase the patient comfort.

Indications of Laser Hair Reduction 1. Unwanted body hair in individuals with more than 15 years of age (IADVL task force recommendation) 2. Hirsutism 3. For special conditions—pseudofolliculitis barbae, pilonidal sinus. An ideal patient is the one with coarse, dark, terminal hair in absence of underlying hormonal imbalance and has realistic expectations (Figs 6.1 and 6.2).

Contraindications of Laser Hair Reduction They can be subdivided into absolute and relative. Absolute contraindications include Photosensitive disorders, e.g. systemic lupus erythematosus, presence of active infection in the local area, e.g. herpes labialis, staphylococcal infection.

Fig. 6.1: An ideal patient with dark terminal hair

Fig. 6.2: A patient with coarse thick black hair on the chin, an ideal case for laser intervention

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Relative contraindications include patients with superficial cuts and injuries in the local area as it makes the skin more prone to laser burns, keloidal tendency and patient with unrealistic expectations. Isotretinoin makes the skin dry hence chances of burns increase. Also it alters the fibroblastic response, hence healing is delayed. Hence in patients on isotretinoin, laser should be avoided. Gap between laser and isotretinoin depends on the dosage used. Ideally a 6 months gap is recommended if patient is on this drug for 6 months.

Hair Removal: an Evidence-based outlook Various studies have reported on the efficacy of different laser systems to reduce hair growth, and reduction in the number of hair counts is the endpoint most often evaluated. To make meaningful comparisons between treatments, it is important to consider under which circumstances the treatment results are reported, because huge diversities are seen in terms of study design (randomized and nonrandomized controlled studies, uncontrolled studies, retrospective studies, case reports); patient inclusion; treatment settings, including specific devices; number of treatment sessions; and follow-up periods. To demonstrate the true effectiveness of laser and IPL devices, two definitions can be employed: Hair reduction estimated up to 6 months after treatment is considered as “short-term efficacy” and beyond 6 months postoperatively as “long-term efficacy.”

Hair Removal Devices The current market for laser hair reduction is growing so rapidly that the FDA has not maintained an up-to-date listing of all approved laser devices. Currently used lasers fall into one of four categories: the long-pulsed ruby laser (694 nm), the long-pulsed alexandrite laser (755 nm), the long-pulsed semiconductor diode laser (800–810 nm), and the long-pulsed Nd:YAG laser (1,064 nm). Additionally, the Intense Pulsed Light (IPL) system (515–1,200 nm) is approved as a safe and effective method for hair reduction . ELOS has been used but is not as effective as other systems. Other devices that have not been included in the table 6.2 include fluorescent pulse light , optical light energy combined with RF (eMax/eLight of Syneron) and diode combined with RF (eLaser Syneron and MeDiostar Effect Ascepelion).

Home Use Devices They have recently gained popularity due to the low cost involved and convenience of the patient. Home use devices have their own set of safety concerns as they are being used by untrained professionals.

Lasers for Hair Removal  259 Table 6.2 Overview of some of the FDA approved devices for hair removal Laser

Devices

Patient type

Hair reduction

Hair removal

Long-pulsed ruby lasers (694 nm)

E2000 Epitouch Ruby Ruby Star Sinon

I–III (SPT) Hair: Dark to light brown Fine and coarse

38–49% hair reduction

Long-term hair removal

Long-pulsed alexandrite lasers (755 nm)

Apogee Arion Epicare Epitouch ALEX Gentelase Ultrawave II/III

I–IV (SPT) Hair: Dark to light brown Fine and coarse

74–78% hair reduction

Long-term hair removal

Pulsed diode laser (800 nm)

Apex-800 F1 Diode Laser LightSheer MedioStar SLP1000

I–IV (SPT) Hair: Dark to light, brown and coarse

70–84% hair reduction

Long-term hair removal

Long-pulsed Nd:YAG lasers (1,064 nm)

Acclaim 7000 Athos CoolGlide Dualis Gentle Yag Lyra Mydon Profile Smartepil II Ultrawave I/II/III Varia Vasculight Elite

I–VI (SPT) dark and coarse hair

29–53% hair reduction

Long-term hair removal

Intense pulsed light source (515–1,200 nm)

Ellipse EpiLight Estelux PhotoLight ProLite Quadra Q4 Quantum HR Spatouch SpectraPulse

I–VI(SPT) Dark to light brown and coarse hair

49–90% hair reduction

Long-term hair removal

Home-based devices are based on IPL and laser technologies but operate at lower fluences than comparable in-office devices. The 810-nm diode Tria laser (Tria Beauty, Inc, Dublin, CA) and 475 to 1,200 nm IPL Silk’n device (Home Skinovations, Kfar Saba, Israel) are the current FDA-approved home use hair removal systems. One safety feature on most home-use devices is a skin contact sensor that prevents the beam from firing when not on the skin. Light is supposedly selfcontained within the device, and special protective goggles are not required, but if eye precautions are breached, irreversible corneal burns, lens cataracts,

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and retinal damage may result. Aside from ocular damage, unintentional misuse by individuals with darker skin type or a tan or inappropriate treatment of moles or tattoos may lead to thermal burns.

Results of LHR Evidence for Short-term Efficacy (up to 6 Months After Epilation) Substantial evidence exists for a short-term efficacy of hair removal up to 6 months after treatment with the ruby laser, alexandrite laser, diode laser, Nd:YAG laser, and IPL. The efficacy is improved when repetitive treatments are given and there is considerable evidence that the short-term efficacy from photoepilation is superior to conventional treatments with shaving, wax epilation, and electrolysis. Overall, the short-term efficacy is reported between 30% and 70% hair reductions up to 6 months after the last treatment; the treatment outcomes depend on the treatment settings.

Evidence for Long-term Efficacy (Beyond 6 Months After Epilation) Evidence was found for a long-term efficacy of hair removal after repetitive treatments with the alexandrite laser, the diode laser, and the long-pulsed Nd:YAG laser. It may be possible that repetitive treatments with the ruby laser (3–4 treatments) and IPL (5 treatments) are capable of inducing long-term hair reduction as well, although the actual evidence is sparse. The overall results from long-term studies with the alexandrite, diode, and Nd:YAG laser vary a lot, but show on average a 50% hair reduction from repetitive treatments with these devices (Table 6.2).

Procedure Preoperative 1. Patient counseling, expectation alignment and informed consent: A detailed consent form should be developed which should include details regarding the procedure, the expected results and rare side effects that can be expected with the treatment. The patient should be clearly informed in the beginning and before every subsequent session that the laser would give a very good delay of growth, decrease the number of hair and make the hair finer but it will not cause removal of all the hair. The patient has to be informed regarding the gap between the sessions (according to the body part being treated). In between the sessions, the patient can theoretically use hair removing creams or shave the area. The authors preferably avoid using hair removal creams as irritant reactions are very common. The patient should also be informed regarding the number of sessions, requirement of maintenance

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sessions and the total cost of the procedure. In case any hormonal imbalances concomitant therapy may be needed. 2. History and examination: A detailed history including age of onset of hair growth, menstrual history, and any concomitant drug intake should be taken. Any previous treatments taken for the same should be recorded. If the patient is suspected to be having hirsutism due to underlying polycystic ovarian disease, a complete work up should be done including the ultrasound pelvis to rule out polycystic ovarian disease (PCOD) along with hormonal profile. An endocrinological opinion can be sought for the same, if required. Appropriate medical therapy should be initiated and patient should be aligned regarding the more number of sessions that would be required. Patients with an sudden onset of hypertrichosis should be evaluated for paraneoplastic etiologies. History of any photosensitizing drugs, colloid and hypertrophic scars, history of recent sun exposure and tanning, parlour activities and occupations involving prolonged exposure to sun should be recorded. Patient should be asked regarding photosensitive conditions, such as the autoimmune connective tissue disorders, or disorders prone to the Koebner phenomenon. A history of recurrent cutaneous infections at or in the vicinity of treatment area might warrant the use of prophylactic medications. Topical retinoids used in the treatment area should be discontinued at least 4 days prior to treatment. There are divided opinions regarding use of oral retinoids along with laser treatment. Majority of clinicians recommend a washout period of 6 months to one year after stopping the drug. The patient is assessed for the Fitzpatrick skin type, as darker skin types are more prone to adverse effects related to laser therapy, e.g. burns or postinflammatory hyperpigmentation. Examination is done for the presence of tan. If present, the treatment should be deferred till subsidence of tan. Tanned type 4 skin is more prone to burns than type 5 skin. One of the most important steps in evaluation of patient for LHR is assessment of patient’s hair color. It is important as the chromophore for LHR is melanin. Black and brown hair contain sufficient amounts of melanin to serve as a chromophore for LHR. In contrast, the lack of melanin, paucity of melanin, or presence of eumelanin in the hair follicle, which clinically correlates to white or gray, is predictive of a poor response to LHR. 3. Investigations: Ideally all females with hirsutism in the reproductive age group should be investigated between 2 and 5 day of cycle. Free testosterone is usually the best marker. 17 alpha OH progesterone test done during the luteal phase, is good for investigating females with normal cycles. LH:FSH ratio of 1.6 or more has been proposed to be a marker for evolving PCOS, especially in young females. Altered ratio is also a marker for end organ hypersensitivity. Ultrasongraphic string of pearl appearance is considered a useful investigation.

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4. General Advice to Patients: The patients are advised not to carry out parlor activity like waxing, threading, plucking or bleach 3 weeks before the first session and in between the sessions. Use of hair removing creams should be discouraged due to the chances of irritant reaction. The patients are allowed to shave in between the sessions. The patients can use bleach with 1 month gap before and after the session, when the gap between sessions is more than 3 months and during the maintenance phase. 5. Pre- and post-procedure photographs: Keeping a photographic pre-, post- procedure and in-between sessions in comparable setting is important. It helps the patient as well as the treating physician to compare the response/ nonresponse. Trichoscan images can prove to be extremely useful for monitoring the results. Patient’s records should be maintained including the exact area treated, skin and hair type, the fluence used and wavelengths used during all sessions and treatment response.

Intraoperative Intraoperative anesthesia: Topical anesthetic creams are available. They are used especially for sensitive areas, e.g. pubic region. However, the authors do not prefer the use of topical anesthetic preparations as they have a high potential of causing irritant reactions and subsequently burns with laser. They also increase the cost of a given session and the time required to complete a session. Also cooling is a very effective alternative. The need for topical anesthesia is variable among patients and anatomic sites. Various topical anesthetics including lidocaine, lidocaine/prilocaine, and other amide/ester anesthetic combinations can be used to diminish the procedural discomfort, and should be applied 30 minutes to 1 hour before treatment under occlusion. Care should be taken when using lidocaine or prilocaine to apply these medications to a limited area to diminish the risk of lidocaine toxicity or methemoglobnemia, respectively. Deaths have resulted from lidocaine toxicity resulting from occlusion of the back as well as lower extremities with topical lidocaine. Likewise, systemic toxicity can occur with the use of any topical anesthetic in large amounts. Test patch: A small test patch area should ideally be done before the first session to determine the optimum fluences and skin reaction to the laser. It is especially useful in dark skin types to establish the optimum fluences that can be used in these patients without causing any burns. Procedure: Procedure is re-explained to the patient in brief. The skin is checked for any sensitive areas, tanning or any cuts under adequate light with a magnifying glass. Depending on the area to be treated, the patient can be in a supine or sitting position chairs or adjustable operation tables. 1. Marking: The area to be lased is marked with a white pencil under adequate light. Red pencil can be used with IPL. Small grids should be made for large areas.

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2. Shaving: Cleansing gel is applied and the area is shaved taking care not to leave any hair behind and at the same time avoid any cuts on the skin due to vigorous shaving. Magnifying glass should be used to ensure proper shaving. Shaving against the direction of hair should be avoided (Fig. 6.3). 3. Cooling: Pre-cooling, post-cooling and cooling during the session is absolutely mandatory. Chill tip is very effective for this. Ice packs can be used for large body parts. 4. Gel application: Cool gel in a thin layer needs to be applied in all lasers except the big hand piece of light sheer duet. 5. Eye protection: Patient and operator should wear glasses. The parameters are decided on the basis of hair and skin type. The hand piece of the system should be placed perpendicularly to the skin surface and it should be pressed gently to displace blood from capillaries and to bring the hair follicle nearer to the aiming source (this is particularly important if you are using Nd:YAG laser). Overlapping of handpieces in treating adjacent areas (10%) is ideal as it avoids skipping of areas. Laser shots are given at the optimum fluence according to the skin and hair type and the response of patient to patch test or previous sessions.

Postoperative 1. Post-procedure care: There can be mild-transient erythema and perifollicular edema. A steroid antibiotic cream can be used. Oral antiallergic or rarely oral steroids might be needed in case of a burn. All the patients are advised regular use of sunscreen and use of a moisturizing cream for 5 days after any laser session. 2. Patient follow-up: The best time to evaluate the effect of laser session is 2–3 weeks post the session (Figs 6.4 and 6.5). Non-responsive Lesson: The patients with fine (Fig. 6.6), gray (Fig. 6.7)/ blonde/light brown hair have inadequate pigment in hair hence do not respond well.

Fig. 6.3: Shaving against the ‘grain’ leading to erythema and bleeding points

264  Lasers in Dermatological Practice

A

B

Figs 6.4A and B: (A) A patient treated with long-pulsed Nd:YAG laser; (B) Treatment response after 6 sessions of long-pulsed Nd:YAG laser

A

B

Figs 6.5A and B: Treatment response after six sessions of long-pulsed Nd:YAG laser. (A) Preoperative; (B) Postoperative

Lasers for Hair Removal  265

Fig. 6.6: A patient with a few gray hair it must be emphasised that the nonpigmented hair are unresponsive

Fig. 6.7: A patients with multiple gray hair, which is not a candidate for LHR

If very low fluences are used, patients do not get the desired response. Low energy machine which is not delivering the right energy is another factor for non-response. Underlying hormonal disturbances is also a reason for suboptimal response.

Side Effects In majority of cases, the side effects are transient and easily remediable. Sun protected regions are less likely to suffer from side effects as compared to photo-exposed areas, e.g. face and arms. The most common skin reactions are pain during session, mild burning, transient erythema post-session, perifollicular erythema. In very few cases persistent erythema, vesiculation, crusting, hyperpigmentation, hypopigmentation and permanent scarring can occur. Thermal burns can occur which can be superficial or deep. This may result either from selecting a non-optimal wavelength, pulse duration, fluence, nonfunctional epidermal cooling, or by treating a tanned patient.

266  Lasers in Dermatological Practice

Superficial burns (Fig. 6.8) are more prone to occur in patients with tan, dry skin or rigorous shaving. They need couseling, mild topical steroids and moisturizers. If a patient has extreme burning sensation, there is high probability that a deep burn (Fig. 6.9) has occurred. For this, the patient should start oral steroids (dose of 1 mg/kg body weight) for three days. After three days, advice the patient to use a steroid antibiotic combination and bland moisturisers. Hyperpigmentation can be treated with mild agents like topical vitamin C and strict sun protection. Paradoxical hair stimulation (Fig. 6.10) can occur as a side effect. Few patients have increased hair growth at sites surrounding previously treated sites or increase in hair growth over the treated site. This effect tends to occur more frequently in patients of skin types III or higher, more commonly with IPL and in an adjacent area of untreated skin. This effect has also been reported in individuals with previously undiagnosed hormonal conditions, such as polycystic ovarian syndrome, emphasizing the importance of history taking and proper patient selection in laser hair removal. The paradoxical hair stimulation occurs probably due to lower-range fluence. Use of higher fluences reduces this side effect.

Fig. 6.8: Superficial laser burns, consequent to inadequate cooling

Fig. 6.9: Deep laser burns in a patient of laser hair removal

Lasers for Hair Removal  267

Fig. 6.10: Paradoxical hair stimulation seen in a pigmented skin patient

Increasing the area to be lased in the maintenance sessions is another very common cause of paradoxical hair stimulation. Inadequate cooling can also lead to paradoxical hair stimulation. Especially when working with IPL, the surrounding area should also be cooled as unlike lasers, IPL is not a coherent beam and heat can lead to increased hair growth. Ocular injury is another potential complication of laser hair removal.

Pearls and Pitfalls 1. Spacing between sessions: Face—The authors recommend that the first two sessions can be done at an interval of 4 weeks to target the hair in the early anagen phase, after that the gap can be increased. The resting phase of facial hair is around 4 weeks. One of the most prominent effects of laser is the prolongation of the resting phase. Hence we recommend that the sessions should be spaced out from the 3rd session itself to target the hair in the anagen phase. Preforming the sessions frequently might lead to a temporary suppression rather than destruction of hair follicle. If large body parts are to be treated the authors recommend that the gap between first and sessions should be 6–8 weeks and gradually the gap can be further increased in subsequent sessions. 2. Maintenance sessions: These are regular laser sessions done at frequency of 1–3 times per year. The frequency depends on the area treated and the response of laser sessions. 3. Long hair (Fig. 6.11): This process is known to happen with all kinds of hair reduction technologies. The lased hair is pushed into a prolonged anagen phase. The patient should be informed about this in the beginning and proactively advised to use scissors to cut these long hair in the maintenance phase.

268  Lasers in Dermatological Practice

Fig. 6.11: Persisting long hair—a process known to occur with all kinds of hair reduction technologies

Safety Issues Standard Precautionary Measures 1. Eye protection: The recommended eye protection devices should be used at all times by any person present in the laser room. Clinician’s eyewear: Appropriate protective eyeglasses according to the wavelength of laser being used has to be worn by the clinician. Patient’s eyewear: Opaque or metal goggles, corneal shields, or protective wet eye pads should be used by the patient during the procedure. The clinician/patient should never look directly into laser aperture, even when wearing laser safety glasses. Avoid directing laser beam anywhere other than within holster or at intended treatment area. Remove mirror-like surfaces from vicinity of laser beam path. Do not treat eyebrows, eyelashes, or other areas within bony area surrounding orbit. This topic is extensively discussed in the appendix of the book. 2. Fire protection: Flammable or explosives should not be used in the laser room. Acetone or alcohol-based skin preparations should not be used. Fire-retardant drapes and gowns should be used. Fire extinguisher and water should be readily available in the clinic. 3. Electrical safety: Many lasers use high voltage and high current electrical power, ensure proper grounding. Proper cables should be used instead of extension cords. Good wiring and proper stabilizers should be used.

Special Situations 1. Role of eflornithine along with laser hair reduction: The role of topical eflornithine is still controversial. It is being used by some practitioners

Lasers for Hair Removal  269

in the maintenance phase to delay hair growth. Twice a day application is suggested and the results are usually seen after 4–6 weeks. This can lead to acne in patients with acne prone skin and it also significantly increases the cost of therapy for the patient. 2. Polyscytic ovarian disorders (pcod) and laser hair reduction: In case of clinical signs suggestive of PCOD (like abnormal cycles, acne over lower face, obesity and thinning of frontal hair), a hormonal profile should be carried out between the 2nd and 5th day of the cycle and an ultrasound of the lower abdomen is advised. In cases where PCOD is documented, an endocrinological opinion should be sought. The patients are started on medical therapy followed by laser treatment from the second month onwards ideally. Many practitioners start medical and laser therapy simultaneously. These patients should be counseled regarding the requirement of increased number of sessions. 3. Laser for gray hair: Melanin is the chromophore targeted by laser. Gray hair lack melanin, hence the treatment is unsuccessful. The patient should be informed in advance that these hair will not respond to laser and as the number of black hair decreases, the patient would feel that number of gray hair has increased. Few gray hair can be managed by electrolysis. If the percentage of gray hair is more than 50%, laser should be avoided. Removal of non-pigmented hairs with a combined light/bipolar radio-frequency device with or without pre-treatment with a topical photosensitizer has shown little success. Integrated radiofrequency and optical energy technology might represent a new photoepilatory technique for the long-term removal of white hair. Although results may not be quite as efficient as with chromophore targeting primarily lightbased technologies. A recent alternative approach to treat white, blond and gray hair with laser hair removal has been the external application of melanin to the hair through the use of liposome technology. Melanin-encapsulated liposomes have demonstrated to selectively deliver melanin to the follicle and hair shaft. The effectiveness of these modalities for gray hair still needs to be proved. 4. Lasers for fine hair: In Indian skin due to the high melanin content and the risk of burns, very high energies cannot be used with any laser systems. For patients, who are left with fine hair after receiving a number of laser sessions, the pulse width needs to be decreased and high fluence levels are needed. Hence, patients with fine hair should be dissuaded for laser hair reduction. 5. Pseudofolliculitis: Laser hair reduction is a very effective treatment for pseudofollicultis seen post waxing in females and post shaving in males. The laser should be done at low energy levels and usually 3–4 sessions are sufficient to make the hair fine and hence solve the problem of pseudofolliculitis (Figs 6.12 and 6.13).

270  Lasers in Dermatological Practice

Fig. 6.12: Patient with pseudofolliculitis barbae treated with hair reduction lasers

Fig. 6.13: Same patient after two months after first session with Nd:YAG laser

6. Lasers in dark skin types: There are several characteristics which make skin of dark color more susceptible to laser-related complications. There are several factors which can be taken into account to minimize the complications: Wavelength: Use longer wavelengths as they are associated with less epidermal absorption and hence greater safety. Treatment parameters: Use lower (optimum) fluences and longer pulse durations for laser hair removal. These can be determined by doing a patch test. Pre- and post-treatment advice: Sun protection is an important aspect to prevent any complications, e.g.postinflammatory hyperpigmentation. Epidermal cooling: Adequate cooling is one of the key factors in determining the safety.

Lasers for Hair Removal  271

Topical corticosteroids: Consider using in patients with post-treatment erythema or edema to reduce chances of post inflammatory hyperpi­ gment­ation. 7. Laser in pregnant women: Treatment of a pregnant woman for nonurgent conditions is discouraged, although there is no evidence suggesting a potential risk to pregnant women undergoing LHR.

Future Advances 1. Pain free lasers: A novel technique to reduce LHR-associated pain is pneumatic skin flattening (PSF). PSF works by coupling a vacuum chamber to generate negative pressure and to flatten the skin against the hand piece treatment window. Based on the gate theory of pain transmission, it stimulates pressure receptors in the skin immediately prior to firing of the laser pulse, thereby blocking activation of pain fibers. Light sheer ‘duet’ has pneumatic skin flattening in which vacuum is used for decreasing the pain. Alma Lasers’ unique IN-MotionTM technology combines concurrent cooling with a gradual thermal rise to the target’s therapeutic temperature, without the risk of injury and with much less pain for the patient. This is in contrast to the high peak energies used in traditional photoepilation technology that requires high cooling before, during and after each pulse, and requires that the handpiece remains stationary during the energy delivery. The sweeping technique of IN-MotionTM technology enables continuous administration in a larger treatment area for increased comfort and fewer missed spots. 2. Meladine, a topical melanin chromophore, has been studied in Europe with interesting results. The liposome solution dye, which is sprayed on, is selectively absorbed by the hair follicle and not the skin. This gives the follicles a temporary boost of melanin to optimize laser hair removal treatments. Clinical studies in Europe have shown vast permanent hair reduction in patients who used meladine prior to treatment. 3. Studies have shown that eflornithine in combination with the alexandrite or Nd:YAG laser (Fig. 6.13), may increase the efficacy of laser hair removal and that topical melanin improves the efficacy of the diode laser. 4. Photodynamic therapy (PDT) with aminolevulinic acid (ALA) has been shown in a small pilot study to result in up to 40% hair reduction with a single treatment, although wax epilation was performed prior to treatment in this study. 5. Electro-optical synergy (ELOS) technology combines electrical (conducted radiofrequency) and optical (laser/light) energies. A handful of devices based on this technology have been produced. The theory behind ELOS is based on the optical component (laser or IPL)

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heating the hair shaft, which then is thought to concentrate the bipolar radiofrequency (RF) energy to the surrounding hair follicle. Based on this combination, lower fluences are needed for the optical component, thereby suggesting it might be well tolerated in all Fitzpatrick skin phototypes, and potentially effective in the removal of white and poorly pigmented hair. A study of 40 patients (Fitzpatrick skin phenotypes II–V) with varied facial and non-facial hair colors were treated with combined IPL/RF ELOS technology. An average clearance of 75% was observed at 18 months following four treatments. No significant adverse sequelae were noted and there were no treatment differences between patients of varying skin types or hair color. Pre-treatment with aminolevulinic acid (ALA) prior to use of a combined IPL and radiofrequency device has been shown to further augment the removal of terminal white hair. As hair removal lasers are possibly the most common indication in the laser industry, more advances are bound to take place to tackle some of the special situations detailed in the chapter.

Bibliography 1. Buddhadev RM. Standard guidelines of care: Laser and IPL hair reduction. Indian J Dermatol VenereolLeprol. 2008;74:S68-S74. 2. Faurschou A, Haedersdal M. Photoepilation of Unwanted Hair Growth. Raulin C, Karsai S (Eds). Laser and IPL Technology in Dermatology and Aesthetic Medicine, DOI: 10.1007/978-3-642-03438-1_9, © Springer-Verlag Berlin Heidelberg, 2011. 3. Murphy MJ, Torstensson PA. Thermal relaxation times: an outdated concept in photothermal treatments. Lasers Med Sci. 2013. 4. Nanda S, Bansal S. Safety and efficacy of Nd YAG Laser in type IV and V skin: a study on 200 patients. Indian J Dermatol. 5. Tierney EP, Goldberg DJ. Laser hair removalpearls. JCosmet Laser Ther. 2008; 10:17-23.

Section

Advanced Laser Interventions

2

Chapter

7

Nonablative and Subsurface Rejuvenation Kabir Sardana

Introduction The demand for newer methods of skin resurfacing (for acne scarring, pigmentation, and improvement of skin texture and pore size) has made the use of nonablative lasers and light devices popular in clinical practice. These treatment modalities work on deeper skin layers without removing the epidermis, resulting in collagen synthesis and remodeling without protracted healing. Consequently, nonablative technology has several benefits. Most importantly, it is a safe and effective treatment in all skin types and colors with a minimal amount of required recovery time. A clear definition of nonablative skin rejuvenation is important as the term is sometimes used haphazardly. There are some terms that have different connotations. 1. Nonablative rejuvenation: This is defined as improvement of skin quality without physical removal or vaporization of the skin. 2. Nonablative fractional rejuvenation (NAFR): This implies the use of fractional lasers, which work by removing a fraction of the skin with an intact epidermis, thus leading to mimimum down time and rapid healing. 3. Subsurface lasers: These are lasers and light sources that work by altering the tissue below epidermis and is akin to the term “nonablative laser resurfacing” or laser toning. 4. Minimally ablative lasers: This term includes procedures where a proportion of the epidermis is also targeted and includes lasers like the KTP lasers, light devices like IPL and fractional ablative lasers and LED. In practice as photodamage has a marked epidermal component, these devices are more useful than pure subsurface lasers for the indication. As discussed below in an endeavor to bridge the gap between less side effects and results the tide has turned and ablative fractional lasers (AFR) are also being increasingly used, which are strictly not nonablative lasers.

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Mode of Action Most of these devices work by targeting the dermis. They work either by, targeting discrete chromophores in the dermis and/or at the dermal epidermal junction. They primarily use mid-infrared lasers in the range of 1.3–1.55 µm wavelengths, where water absorption is weak enough so that relatively deep beam penetration is allowed (there is only 50% beam attenuation at depths of 300–1,500 µm). The classification system of Richard Glogau (Table 7.1), is useful to assess clinical photoaging. The importance of this is that patient of Grade I are easy to treat while Grade II and III require a combination of approaches. One can follow a patient from an early age, with relatively strong homogeneity of skin coloration and minimal wrinkles, to a more aged patient, with wrinkles at rest and a more heterogeneous skin coloration. Treatment of photodamage can be divided into various categories, and treatment protocols are based on a logical approach founded on the lasertissue interactions delineated above. The goal should be to maximize skin rejuvenation, from reducing telangiectasias and lentigines to enhancing dermal remodeling.

Classification of Lasers The main classifications of lasers and light sources utilized for photorejuvenation are outlined in Box 7.1. Though we admit that this such classifications is arbitrary as many devices are capable of delivering multiple wavelengths. Table 7.1 Classification of photodamage skin Grade

Classification

Age

Wrinkles

Clinical findings

Cosmetic camouflage

I

Mild

20s or 30s

No wrinkles

Early photoaging: Mild pigmentary change No keratoses Minimal wrinkles

Minimal or no makeup

II

Moderate

30s or 40s

Wrinkles in motion

Early to moderate photoaging: Early solar lentigines, keratoses palpable but not visible Parallel smile lines begin to appear

Wears some foundation

III

Advanced

50s

Wrinkles at rest

Advanced photoaging: Dyschromia Visible telangiectasias Visible keratoses

Always wears heavy foundation

IV

Severe

60s and older

Only wrinkles

Severe photoaging: Yellow-gray skin color Wrinkles throughout

Makeup ‘cakes and cracks’

Nonablative and Subsurface Rejuvenation  277 Box 7.1 Lasers and light sources used for photorejuvenation* Class

Laser/Device

Energy

Visible light/ Vascular–selective laser

KTP lasers (532 nm) Diode pumped

Up to 950 J/cm

5–100 ms

0.1–5 W

5–1000 ms

Visible non–laser light sources

Pulse duration 2

0.45–40 ms

PDL (585/595)

Up to 40 J/cm2

Intense pulsed light (IPL) – (500–1,200 nm)

Up to 70 mJ/cm

1–500 ms

Q–switched and millisecond domain Nd:YAG 1064 nm

Up to 16 J/cm2 Up to 990 J/cm2

5–20 ms 0.1–300 ms

1,319 nm Nd:YAG laser

Upto 30 J/cm2

5–200 ms

1,320 nm Nd:YAG laser

5–40 J/cm2

30–200 ms

1,450 nm diode laser

Up to 25 J/cm

201–250 ms

1,470 nm diode laser

12 W

5–1000 ms

1,540 nm erbium glass laser

10–30 J/cm

2

LED (light–emitting diodes) Infrared lasers (target pigment, hemoglobin and water)

Plasma–RF

2

2

3–100 ms

0.5–4 J

*Radiofrequency (RF), microwave and ultrasound

1. The first category is visible light lasers or light sources that have more absorption by hemoglobin and melanin. These visible light sources and lasers have more influence on the telangiectatic and melanocytic components of photoaging. These sources can be subdivided into co­ her­ent, single wavelength, broadband (flashlamps) or narrow­band such as light-emitting diodes (LED). Intense pulsed light is a broadband light source with filters used to limit the lower end of the emitted spectrum. 2. The next category is infrared lasers with absorption predomi­nantly by water. Infrared wavelengths with primarily water absorption are used to create thermal dermal and collagen injury. The most commonly employed devices are 1,320 nm, 1,450 nm and 1,540 nm lasers, although narrow­band infrared LED devices, other filtered light sources and possibly ultrasound may be available in the future. 3. Another category is the near infrared lasers or light sources, which are absorbed by a combination of melanin, hemoglobin and water. The tradeoff is that these wave­lengths are absorbed at a lesser intensity but cover more targets. The flashlamp pumped 1,064 nm Nd:YAG laser is the most commonly used example. The broadband flash­lamp pumped light sources also have a number of effects for structural photorejuvenation in that they emit not only wavelengths absorbed by melanin and hemoglobin, but wavelengths absorbed by water as well. IPL broadband sources emit 515 nm to 1,200 nm.

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4. Other devices on the market use RF to heat tissue. Depending on the delivery system and frequency, deep or superficial heating can be produced. Monopolar RF has a very different and deeper penetration (as the result of the patient being grounded) than bipolar RF devices, in which the RF travels from one electrode to another over relatively short distances. Microwave devices have been used to heat specific targets such as blood vessels or hair but none have been commercialized. Use of nondiagnostic ultrasound frequencies may also be used in skin tightening. 5. Fractional resurfacing is a method of microablative, pixel like damage of the skin with rapid healing resulting in skin contraction, dermal collagen thickening and improvement in rhytides. The vascular lasers are operated at subpurpuric fluences and pulse durations with minimal overlap during passes (Box 7.1). Approximately five treatments are administered every 3–4 weeks. The IPL devices vary among systems, but all require cold aqueous gel application prior to treatment. A series of 5–6 sessions is usually necessary with multiple passes during each session. Infrared lasers are operated at the highest tolerated energy level to ensure the best results. A cryogen spray is delivered milliseconds before laser pulsing in order to protect the epidermis from thermal injury. Treatments generally occur in a series of 5–6 sessions at 2–4 week intervals. Depending on the laser used, 1–3 passes with the laser can be made per treatment (Box 7.1). Unlike the nonablative lasers, light-based treatments like the LEDs do not cause gross thermal heating, but instead cause subtle molecular changes in the tissue for clinical improvement. For example, yellow (590 nm) LED irradiation is known to downregulate metalloprotease-1 (collagenase) and stimulate fibroblasts to increase procollagen production, while continuous red (633 nm) LED irradiation stimulates mast cell degranulation and increases fibroblast growth factor production. The pulsed yellow LED, when used twice a week for 4 weeks, was shown in two prospective blinded studies (with 183 patients) to mildly improve skin texture, dyspigmentation, erythema, and fine lines in the periorbital region in the majority of patients as assessed by blinded observers, patient reports, digital microscopy, and ultrasound. The recommended treatment course consists of less than 1 minute irradiations twice a week for 4 weeks, followed by a monthly booster treatment. Exfoliation with an enzymatic peel or microdermabrasion prior to treatment is also recommended. In order to bridge the gap between nonablative and ablative devices, fractional resurfacing technique was developed. Similar to nonablative lasers, the fractional laser (1,550 nm erbium-doped and 1,540 nm erbium:glass) emits infrared light that is absorbed by water-containing tissue. Further, technological developments have resulted in the use of the radiofrequency and light devices for skin rejuvenation, particularly for the treatment of skin

Nonablative and Subsurface Rejuvenation  279

laxity by heating deeper skin and subcutaneous tissue, causing skin and tissue tightening. These devices have been discussed previously. A new RF tool, the ‘Portrait’ plasma skin regeneration (PSR 3) device, has been shown to improve skin texture, tone, fine lines, dyschromia, and rhytides. The plasma is emitted in millisecond pulses to deliver energy to the desired tissue without reliance on a skin chromophore, and energy settings on the device can be varied for different depths. One disadvantage of this technology is that there is about a 1-week period of required downtime.

Vascular Lasers Studies have shown that KTP lasers have better collagen formation results when compared to 1,064 nm lasers in the treatment of skin photorejuvenation. Pulsed dye lasers (PDL) function best in the treatment of vascular lesions (i.e. port wine stains and hemangiomas) with significant production of procollagen type I and type III. Increased activity of dermal fibroblasts and mucin, as well as the thickening of the stratum spinosum in the dermis, has been noticed in the restoration of degenerated skin. The use of modern PDL systems for skin rejuvenation provides nonablative results by minimizing sideeffects and reducing purpura.

Study Results Zelickson and Kilmer determined that purpurogenic doses of the PDL also induced fibroblast proliferation and the production of the Grenz zone of new collagen in the papillary dermis, beneficial for resurfacing. Though early studies, showed a good histological response, there was little patient satisfaction. In 2004, Trelles et al. compared the effects of the 595 nm PDL to a 1,450 nm diode laser and to a combination treatment with both lasers. The combination protocol was found to be better. It has been proposed that the logic of combination is that following the removal of the vascular-associated pigment from the superficial dermis by the PDL, enables deeper penetration of the following pulse with the 1,450 nm diode, helping to amplify the woundhealing response. This has led to a combination approach of PDL with other laser systems (595/1,064 nm). Many other wavelengths that target hemoglobin in blood vessels have been used, which include the long-pulsed 755 nm alexandrite laser, 810 nm diode, and the 1,064 Nd:YAG lasers. The 1,064 nm Nd:YAG laser induces deeper remodeling than the 532 nm laser due to its lower degree of dermal scattering and chromophore absorption at 1,064 nm. Thus, the logic of combining 532 nm laser to treat dyschromia and telangiectasia and following it with the 1,064 nm laser to obtain some deeper remodeling in the same treatment session.

280  Lasers in Dermatological Practice

Intense Pulsed Light Intense pulsed light (IPL) devices emit polychromatic light in broad ranges of wavelengths, selectively filtered to target specific chromophores, between 500 and 1,200 nm. IPLs treat vascular lesions, pigmentation, and have shown to have an effect in the production of collagen and elastic fibers in the dermis. Studies have shown that IPL photorejuvenation treatments using cooling apparatuses considerably increase epidermal thickness, and improve skin texture. This necessitates a proper cooling to avoid the adverse effects relating to skin damaged. The addition of radiofrequency has been utilized to supplement and improve outcomes with use of IPL devices (Elos, Syneron). Bipolar radio­ frequency exhibits a preference for warmer tissue. This technology considers this property by utilizing the IPL system to heat the target chromophore and then using the radiofrequency technology to target the now ‘warmer’ tissue target.

Study Results Bitter et al. studied the effect of a series of treatments with the IPL (photorejuvenation) in 49 patients. After 4–6 IPL sessions every 3 weeks, more than 90% of patients had improvement in all aspects of photoaging: 50% or greater improvement was noted by 46% of patients for fine wrinkles, 72% for skin smoothness, 70% for telangiectasias, 67% for decreased pore size, 59% for facial erythema, and 50% for flushing. In a multicenter study of 93 patients (skin phototypes I–III, Fitzpatrick Wrinkle Classes I–II, and Elastosis Scores 1–6), Sadick et al. gave 5 treatments at monthly intervals with the 560 or 640 nm cutoff filter. The markedly favorable results at 4- and 6-month follow-up visits confirmed its long lasting results. Further studies (Negishi et al.) have used a longer pulse durations with a cutoff filter at 590 nm, to treat photoaging in skin type IV. Long-term followup results have confirmed sustained improvement of the face, neck, and chest up to 4 years after treatment.

Summary Even though newer systems have improved user friendly pre-programmed settings, one should become comfortable with one or two IPL systems as each has different interfaces, wavelength spectrums, filters, power outputs, pulse profiles, cooling systems, and spot sizes. In fact, the variations make it impossible to compare the different IPL devices. This is as some IPL devices that calculate fluences based partly on theoretical modeling and photon

Nonablative and Subsurface Rejuvenation  281

recycling whereas others determine fluence based solely on an actual output at the sapphire or quartz window on the handpiece tip. Our own experience with this modality in Indian skin has been less enthusiastic and we feel that the fluencies recommended can cause side effects and a lower dose can have little objective benefit.

Light-emitting Diodes Light-emitting diodes (LED) provide “athermal and atraumatic” photo­ activation of mitochondria, epidermis and fibroblasts. The singular advantage of LED devices is that they are well tolerated by patients. Typically, LED devices emit a range of wavelengths. The interaction of LED devices with the skin is unclear, though photomodulation of cell receptors, cell organelles, or existing protein products is the possible mechanisom. Unlike many of the devices discussed above, non-thermal interactions with the extracellular matrix and fibroblasts remodel existing collagen, increase collagen production by fibroblasts, inhibit collagenase activity, and result in rhytid reduction. Combination of various LED wavelengths is the key to clinical efficacy. One wavelength will not target all chromophores optimally. Based on the published peer-reviewed literature, a combination of wavelengths is necessary for effective LED phototherapies are given in Table 7.2. The wavelengths used for LED skin rejuvenation have been near IR at 830 nm applied first, followed by 633 nm 72 hours later, repeated over 4 weeks. The reasons for these wavelengths and the order in which they are applied are photobiologically based on the precepts of the wound healing cycle. Both of these wavelengths involve the basal keratinocytes and also target dermal cells, with beneficial effects to both the cellularity and organization of the epidermis (Table 7.2).

Study Results Lee and colleagues, in the first controlled study in the peer-reviewed literature, compared LED skin rejuvenation in a total of 76 patients randomly assigned to four groups: 830 nm LED therapy on its own, 633 nm LED therapy on its own, the combination therapy with 830 nm and 633 nm and a sham irradiated group. All patients were treated hemifacially, so there were intrapatient Table 7.2

A summary of the LED wavelengths and clinical utility

Wavelength

Indications

633 nm + ALA PDT

Non-melanoma skin cancers

Blue 415 nm endogenous PDT + red 633 nm

Acne vulgaris

Near infrared 833 nm + 633 nm

Skin rejuvenation, wound healing

595 nm yellow light

Rosacea, skin rejuvenation

282  Lasers in Dermatological Practice

as well as intergroup controls. In addition, to clinical photography and subjective patient assessment, Dr Lee tested the results with profilometry and instrumental measurement of skin melanin and elasticity. She also carried out histological, immunohistochemical and biochemical assays. She found that wrinkles and skin elasticity were best improved in the 830 nm-treated groups, skin lightening was best in the 633 nm group, so the combination of the two wavelengths was able to achieve the best overall efficacy and high patient satisfaction with the results, with statistical significance seen between all treated groups and the sham-irradiated controls, and a statistically significant improvement between the treated and occluded sides in all of the experimental groups, but not in the sham irradiated group. The clinical photography was backed up by the histological findings for both collagenesis and elastinogenesis, which was proved to take place in all dermal layers down to the deep reticular dermis. A 90-subject prospective study by Weiss et al. (2005) using a 590 nm nonthermal full-face LED (eight treatments over 4 weeks with a minimum of 48 hours between treatments) showed a global improvement of more than 85% and a self-assessment improvement of 84% in patients at 4 months. With digital imaging, there was a 90% reduction in the signs of photoaging: Smoother texture, and reduced periorbital wrinkles, erythema, and pigmentation. However, profilometry results only showed a 10% improvement by surface measurements. In a prospective study using the OmniluxTM LED system, a combination of IR (633 nm) and near-IR (830 nm) light with fluences of 126 and 66 J/ cm2, respectively, 31 patients underwent 9 treatments: 830 nm light on days 1, 3, 5, 15, 22, and 29, and 633 nm light on days 8, 10, and 12 (Russel BA). Patient satisfaction scores, photos, and profilometry were used to assess improvement at 9 and 12 weeks. A clinically significant reduction in surface roughness, maximum profile peak height, and maximum height of the profile was demonstrated. Fifty-two percent of the subjects had a 25–50% improvement in photoaging scores at 12 weeks, and 81% displayed a signifi­ cant improvement in periorbital rhytides at the end of the study. The Gentle Waves device (Light BioScience, LLC, Virginia Beach, VA), which generates a 588 nm yellow light pulses with an on-time of 250 ms and off-times of 10 ms for a total of 100 pulses resulting in a total light dose of 0.1 J/cm2. Boulos found that there was a strong placebo effect with the 588 nm Gentle Waves system, and that little objective improvement was observed by blinded raters. Despite the subjective improvement in two trials, objective improvement in blinded studies is unproven. But as stated above a combination approach is better than the use of a single wavelength. Consequently, LED combination therapy is a safe and effective method of skin resurfacing, but in order to optimize treatment parameters, further studies are necessary.

Nonablative and Subsurface Rejuvenation  283

Infrared Laser The 1,320 nm Nd : YAG laser was the first commonly used nonablative midinfrared laser to rejuvenate skin. The Q-switched 1,064 nm laser systems that stimulate deep dermal collagen stimulation had revealed faster healing than carbon dioxide systems. Further, studies have shown that Q-switched 1,064 nm laser devices significantly decrease solar elastosis and thicken upper papillary dermal zones of collagen. The 1,064 nm Nd: YAG laser devices have useful skin lightening mechanisms for skin rejuvenation. With the use of epidermal cooling devices, such as cryogen, 1,319/1,320 nm laser devices have provided optimal results in the formation of new collagen, reduction of lines and wrinkles. These nonablative laser systems leave the epidermis intact and provide great results in all skin rejuvenating procedures. The 1,450 nm mid-infrared diode laser systems have functioned successfully in the treatment of active inflammatory acne vulgaris, acne scars on the face, fine lines and wrinkles. This laser system targets dermal water, creates a wound in the dermis and triggers the regeneration process of collagen. The 1,540 nm Erbium:Glass laser devices have also clinically shown to help in dermal remodeling by treating fine lines and wrinkles, acne vulgaris and acne scars, and atrophic scars on the face. These lasers use a sapphire lens cooling device throughout the treatment process. One issue with these devices is the side effects that range from dyschromia, purpura, and blistering to scarring. Epidermal cooling techniques are imperative in patients with Fitzpatrick IV–VI type skin. The 1,320 nm Nd : YAG uses either a pre- or post-laser spray, while the 1,450 nm diode laser applies cryogen before, during, and after the laser pulse. These are ideal for Fitzpatrick IV, V, and VI skin types. As in the case of the 1,450 nm system, the total spray time is delivered over a long period (up to 220 ms), there is a risk of cryoinjury. Thus, the shorter spray times with the 1320 nm laser and the 5°C sapphire lens incorporated into the 1,540 nm erbium : glass laser are a better option.

Study Results Infrared laser-1,064 nm Nd:YAG: The LP Nd:YAG laser, like the PDL, is a vasculature-selective device and works best for red pigment and vascular lesions. This has also been used for treatment of photodamaged skin, improving dyspigmentation, skin tone, and texture. Studies by Goldberg DJ, 1997 and Cisneros JL,1998 have shown that the QS laser can be considered as a modestly effective treatment for wrinkles, lentigines, and acne scarring. In 2006, a short-pulsed 1,064 nm Nd:YAG laser was developed for more effective acne scar reduction. This pilot study in 9 patients with moderate-to-severe

284  Lasers in Dermatological Practice

facial acne scars used this laser with a low fluence (14 J/cm2) and after eight sequential treatments (Lipper GM) there was marked improvement in acne scarring. Infrared laser-1,320 nm Nd:YAG: The CoolTouch laser (CoolTouch, Roseville,  CA) was the first device specifically designed for nonablative resurfacing and improving skin texture. It has been tried both in acne and photodamaged skin. Chan et al. studied this laser’s effect on wrinkle reduction and the treatment of acne scarring in 27 Asian females. The protocol was a monthly treatment for 6 months with 3 passes per session and objectively only a mild improvement or no change was seen in most cases. In 2006, Bhatia et al. performed a study utilizing structured interviews of 34 patients 3 months after undergoing a series of 6 monthly treatments with the CoolTouch laser for the treatment of acne scarring or photodamage. This study noticed that patient satisfaction was high and textural improvement were seen. These studies suggest that although the 1,320 nm Nd:YAG shows a mildto-moderate benefit for wrinkling and acne scarring, but patients are more than satisfied with the results than the clinician. Infrared 1,450 nm diode: Similar to the CoolTouch laser, the 1,450 nm diode (SmoothBeam, Candela, Wayland, MA) uses a cryogen cooling device to protect the epidermis during treatment and delivers energy via a 4- or 6-mm spot. In addition to its thermal effects on the dermis, it also damages sebaceous glands, thereby making it a useful treatment option for acne. Mild-to-moderate improvement was seen in 12 of the 16 patients on the treated side in a split face study (Ross EV, 2000). Another study in patients with mild-to-moderate perioral or periorbital wrinkles, Tanzi et al. (2003) demonstrated mild-to-moderate improvement of wrinkles. An increase in dermal collagen was seen at 6 months after the last treatment, and patient satisfaction scores reflected the histological and photographic changes. Tanzi and Alster later compared this laser to the 1,320 nm Nd:YAG for the treatment of atrophic facial scars in 20 patients receiving three successive treatments with a LP 1,320 nm Nd:YAG laser on one side of the face and with a LP 1,450 nm diode laser on the other side. Both lasers improved atrophic scarring but the 1,450 nm diode laser showed a greater clinical scar response. Some authors have suggested that if 3 passes with the 1,320 nm Nd:YAG had been performed improved results can be achieved. As a result, using the 3 pass protocol with the Nd:YAG laser may yield similar or greater results to the 1,450 nm diode laser. Infrared laser-1,540 nm Erbium: Glass (NAFR): The 1,540 nm Erbium:glass laser (Aramis, Quantel Medical, Clermont-Ferrand, France), like the SmoothBeam and  CoolTouch, also uses contact cooling for epidermal protection. Unlike these lasers, it has a smaller spot size (4 mm), and therefore treatments are relatively comfortable and require no topical anesthesia. The 1540 nm erbium:glass laser penetrates to a depth intermediate between

Nonablative and Subsurface Rejuvenation  285

1320 nm (deepest) and 1450 nm (shallowest) and also induces tissue water heating, thermal injury, and neocollagenesis. Fournier et al. determined that the erbium:glass laser results in progressive improvement of perioral and periorbital rhytids at 6 and 14 months. New collagen formation was also noted at the papillary dermis from biopsy specimens. Infrared laser-1,550 nm erbium-doped fiber (NAFR): Manstein et al. performed the first study of the fractional laser by treating 15 subjects with varying densities on the distal forearm. Biopsies taken from the treated sites at 48 hours, 1 week, 1 month, and 3 months were used to help describe the wound-healing process. Results from this study eventually led to FDA approval for the use of the fractional laser for soft tissue coagulation in 2003. Since then, the laser has been sanctioned for the following indications: periorbital rhytides, pigmented lesions, melasma, skin resurfacing, and scarring. This device has been discussed previously in detail and has been the “game changer” as it has managed to optimize results and side effects.

“In Motion Devices “ Near-infrared lasers have been used in a motion technique for skin rejuvenation. The procedure (Laser Genesis, Cutera, Brisbane, CA) is easy to perform and results in only mild erythema postoperatively. This 1,064 nm laser, which has a 5: 7 mm spot size is used in a rapid back-and-forth fashion at 5 Hz and 12–15 J/cm2. The device is moved from region to region based on the surface temperature or patients comfort. Obviously, the lack of anesthetic is imperative in this approach, as excessive pain must be reported by the patient and should alert the operator to move and prevent epidermal injury.

Plasma Resurfacing Plasma resurfacing is a relatively new technology that has been in clinical use  for over 3 years, with 6 years of ongoing trials assessing its efficacy for facial and non-facial skin rejuvenation. The Portrait PSR system is currently the only commercially available plasma resurfacing system to date (Kilmer S, Bentkover SH).

Mode of Action Plasma skin regeneration (PSR) utilizes energy derived from nitrogen gas to create heat that is delivered onto the skin surface resulting in zones of thermal damage and thermal modification. PSR is not chromophore dependent and does not result in vaporization of the epidermis, as is seen with ablative lasers, but leaves a layer of intact, desiccated epidermis that acts as a biologic dressing and promotes rapid healing.

286  Lasers in Dermatological Practice

The histological depth of cleavage is directly related to the pulse energy of the treatment. At settings of 1 J, the line of cleavage extends only to the superficial most portions of the epidermis and at 4 J, the line of cleavage is within the papillary dermis (Fig. 7.1).

Dose Seven treatment protocols are available to treat the full spectrum of patient conditions. These range from a low pulse energy (0.5 J) “lunch hour” procedure with effects and recovery times similar to those of fractional lasers to high energy (4 J) double pass procedures with more dramatic improvements and recovery times of 7–10 days. Protocols are comprised of either single or multiple treatments that can be matched to the patient’s condition.

Indications The PSR has received FDA 510(k) clearance for treatment of rhytides of the body, superficial skin lesions, actinic keratoses, viral papillomata, and seborrheic keratosis. As only one manufacturer for this device is there in the World, there are issues in procuring spare parts for this device. The PSR has beneficial effects in the treatment of dyschromias and photoaged skin, and has been utilized for the treatment of acne scars, eyelid laxity, Hailey-Hailey disease, and linear porokeratosis.

Contraindications Patients with keloid prone skin, active infection, breaks in skin or any cutaneous inflammatory condition, patients who are pregnant or nursing, those who would be deemed ineligible for general surgery, patients with Fitzpatrick skin types V and VI, and those patients who have taken oral isotretinoin within the past 6 months.

Fig. 7.1: Diagrammatic depiction of the depth of the plasma resurfacing device at various doses. Note that at 1 J, the ablation is superficial, while at 4 J the ablation zone is till the dermis

Nonablative and Subsurface Rejuvenation  287

Results Published reports assessing high energy (3–4 J) single pass PSR for facial rejuvenation have demonstrated a mean 50% improvement in skin tone 30 days after treatment. Other reports have shown attenuated clinical improvement over time, e.g. a mean 39% reduction in depth of fine facial lines at 10 days after treatment that decreased to 23% 6 months after treatment. The PSR has been also used for acne scars with a 23% reduction in scar depth at 6 months. Published reports assessing PSR in the treatment of non-facial skin using low energy settings have demonstrated mean clinical improvements of 57%, 48%, and 41% in chest, hands, and neck sites, respectively, and significant reductions in wrinkle severity, dyschromia, and increased skin smoothness were achieved (Alster TS, Konda S).

Conclusion Do We have the Ideal Device for Skin Rejuvenation ? Skin rejuvenation and antiaging have become ‘hot’ topics with almost all the major laser companies jumping on to the bandwagon. Excessive skin exposure to solar UVA and UVB brings about damaging morphological and metabolic changes in the epidermis and dermal extracellular matrix (ECM), combining with and accelerating the effects of chronological aging and resulting in the lax, dull and wrinkled appearance of ‘old’ skin. Oxidative stressors such as singlet oxygen, which are generated following absorption of UV radiation damage the matrix causes elevation of matrix metalloproteinases (MMPs) 1 and 2 and leads to elastotic damage to the underlying connective tissue. As this damage is cause by light, an elegant concept to use the power of light to reverse the damage led to the application of lasers, usually the CO2 or/and the Er:YAG, in what became known as ablative laser resurfacing. Although still regarded as the ‘gold standard’ in the rejuvenation of severely photoaged skin in general and wrinkles in particular, the possibly severe side effects and a prolonged patient downtime of up to several months associated with this approach drastically reduced its popularity. To attempt to overcome these problems, so-called nonablative resurfacing was developed using specially adapted laser or intense pulse light sources. The theory was to deliver a controlled zone of deliberate photothermal damage beneath an intact epidermis, so that the wound-healing processes, including collagenesis and remodeling, could occur under the undamaged epidermis, thereby obtaining rejuvenation of the skin without any patient downtime and was popularized as the ‘lunch-break rejuvenation’. The theory was good, but in clinical practice patient satisfaction was very low, (Trelles MA 2001, Nikolaou VA,2005) because the good dermal neocollagenesis

288  Lasers in Dermatological Practice

seen in post-treatment histological analysis was not reflected in a ‘younger’ epidermis (Orringer JS). In an attempt to bridge this gap between ablative and pure nonablative rejuvenation, so-called fractionated or fractional technology was developed whereby many spots of almost grossly invisible epidermal and dermal ‘microdamage’ were delivered via a scanner or ‘stamp-type’ head, all surrounded by normal epidermis and dermis to obtain swift re­ epithelialization and dermal wound healing. Unfortunately, once again the clinical results were not satisfactory to the majority of patients, with good dermal neocollagenesis not being echoed in the epidermis. In both, the nonablative laser/IPL and the first generation of fractional technologies, the big problem was that what the patient first sees when looking in a mirror is the epidermis, not the dermis. It does not matter to the patient (or her friends) that her dermis is wonderfully better organized if her epidermis remains unchanged, what Dr Glen Calderhead refers to as the SOE syndrome—‘same old epidermis’. Recognizing this, manufacturers of the more recent second generation of fractional systems have returned to the orginal ablative wavelengths, the CO2 and the Er:YAG, in addition to newer media such as Er-doped fiber, to deliver fractionated microbeams that visibly damage the skin, with a recognizable amount of erythema and some edema post-treatment. Thus, we have “reinvented the wheel” so as to speak and gone back to our gold standard of ablative resurfacing. This approach has been much more successful from the patient satisfaction criterion, although at the cost of a little downtime, because it is involving the epidermis more than the previous nonablative and fractional approaches.

How to Choose the Right Device ? The first rule to remember is that no single device can tackle all the problems of a photodamaged skin and secondly dramatic responses are hard to come by and should not be promised to the patient. When selecting a thermal photorejuvenation system, it is therefore critical to understand the physics behind the wavelength and the method of delivery rather than “exag­gerated” manufacturer’s claims. Having knowledge of the output of a device, understanding whether the target is hemoglobin, melanin or water (or all three) and under­standing spot size and method of delivery, the physician may be better able to choose the correct system for the correct application. For example, photorejuvenation of pigmented lesions would not be possible with a unit emit­ting 1,450 nm, for which the target is water and not melanin. This knowledge is also vital if the clinician is to minimize possible adverse clinical events in darker ethnic skin types. Visible light, more strongly absorbed by melanin, must therefore be used with greater caution in darker

Nonablative and Subsurface Rejuvenation  289

skin. A patient concerned about excessive telangiectasia, would be better served by the 532 nm potassium titanyl phosphate (KTP), a PDL, or an IPL device. If the goal is to obtain deeper dermal remodeling, one of the many infrared devices may be needed. An approach to specific patient problems with specific treatments is outlined in Box 7.2. Thus, in clinical practice a combination of laser devices is needed for optimal results (Box 7.2). As the relative benefits of individual devices within in each indications have not compared to determine the ideal device, this leaves this field open to research. Numerous other issues have to be considered some of which are given in Box 7.3. Clinical evaluations of nonablative and minimally ablative therapy generally rely on patient and physician (blinded and nonblinded) assessments of before and after photographs. Additional objective methods of skin texture measurement include profilometry and ultrasound, among others. Differences in before and after results can be subtle, even with the use of digital photography. Though most of the studies in literature have used these parameters some clinicians are not satisfied by the end results. But these therapeutic interventions remain popular among both patients and physicians, suggesting that although differences may not always be clear, results are real. Determining which patients are suitable for skin resurfacing depends in part on the patients’ desires and expectations with treatment.

Box 7.2 A summary of the use of laser/light for treating photodamaged skin Morphology

Devices used

Telangiectasias

IPL PDL LP Nd:YAG (LP 532 nm)

Diffuse-redness (nonvisible telangiectasia)

IPL LED photomodulation

Mottled pigmentation

IPL Nd:YAG (LP) 532 nm LED

Mild rhytides

LED photomodulation IPL PDL Nonablative infrared lasers

Moderate rhytides

Infrared lasers

Deeper rhytides

1,320 nm,1,450 nm, 1,540 nm RF

Acne scars

Erythematous: IPL, PDL, LED Nonerythematous: 1,320 nm, 1,450 nm, 1,540 nm IPL, LED

Texture

532 nm, PDL, Qs Nd:YAG IR laser, LED

290  Lasers in Dermatological Practice Box 7.3 Miscellaneous aspects relevant to nonablative lasers Ideal patient

Glogau grade II or III with mild to moderate photodamage

Dark skin type

Mid-infrared lasers, Avoid light based devices

Fillers and botox

Should precede subsurface laser procedure by 1 hours

Pain

More with IR devices

Edema

More PDL, IPL, or Nd:YAG

Contraindications

Active dermatitis or infection History of keloid / hypertrophic scar formation History of koebnerizing dermatitis (psoriasis, vitiligo) History of photosensitive dermatitis History of oral retinoid use (12 month) Recent medium or deep chemical peel

Nonablative and Subsurface Rejuvenation  291

Step By Step Approach Patient selection is important here as this is one indication where the expectation-outcome is crucial. Thus, it is better to give less expectation to the patient so that the end results achieved are satisfactory!

Patient Selection The ideal patient is a relatively young patient (25–65 years of age), with minimal facial skin sagging, and should be made aware that skin texture and fine lines will improve, but will not be eliminated. Furthermore, since the effects of treatment are cumulative, it is important to reiterate that multiple treatments will be more beneficial than a single treatment.

Pre-procedure The physician should always obtain pre-treatment photographs. The patient should be placed and draped in a position that allows full access to the treatment area. This is typically achieved by placing the patient in the supine position to treat photodamaged areas, such as the face, neck, chest, and forearms. Appropriate goggles or eye shields (internal or external depending on the treatment area) are then applied to assure proper ocular protection. It is helpful to inform the patient who has appropriate eye protection about the likelihood of seeing a flash of light during the procedure. Many patients become anxious regarding the dangers of lasers when they see a flash of light even when they have goggles or shields over their eyes. Informing them that they are adequately protected, even when they see a flash of light adjacent to the shields, puts them at ease.

Procedure It is difficult to detail the various settings required to operate the devices given in Box 7.3. Thus, an individulized approach is needed. But for pigmented skin, it is our view that most of the light based devices should be used with care and the infrared and RF help the patients more than vascular, IPL and PDL devices.

Bibliography 1. Alam M, Dover JS. Nonablative laser and light therapy: an approach to patient and device selection. Skin Therapy Lett. 2003;8(4):4-7. 2. Calderhead RG. Light-emitting diode phototherapy in dermatological practice. K Nouri (ed.), Lasers in Dermatology and Medicine, DOI: 10.1007/978-0-85729281-0_19, © Springer-Verlag London Limited, 2011.

292  Lasers in Dermatological Practice 3. DeHoratius DM, Dover JS. Nonablative tissue remodeling and photorejuvenation. Clin Dermatol. 2007;25:474-9.

Journals 1. Alster TS, Konda S. Plasma skin resurfacing for regeneration of neck, chest and hands: investigation of a novel device. Dermatol Surg. 2007;33(11):1315-21. 2. Bentkover SH. Plasma skin resurfacing: personal experience and long-term results. Facial Plast Surg Clin North Am. 2012;20(2):145-62. 3. Bhatia AC, Dover JS, Arndt KA, Stewart B, Alam M. Patient satisfaction and reported long-term therapeutic efficacy associated with 1,320 nm Nd:YAG laser treatment of acne scarring and photoaging. Dermatol Surg. 2006;32:346-52. 4. Bitter PH. Non-invasive rejuvenation of photodamaged skin using serial, full face intense pulsed light treatments. Dermatol Surg. 2000;26:835-43. 5. Boulos PR, Kelley JM, Falcao MF, et al. In the eye of the beholder – skin rejuvenation using a light-emitting diode photomodulation device. Dermatol Surge. 2009;35(2):229-39. 6. Chan HHL, Lam L, Wong DYS, et al. Use of 1,320 nm Nd:YAG laser for wrinkle reduction and the treatment of atrophic acne scarring in Asians. Lasers Surg Med. 2004;34:98-103. 7. Cisneros JL, Rio R, Palou J. The Q-switched neodymium (Nd):YAG laser with quadruple frequency. Clinical histological evaluation of facial resurfacing using different wavelengths. Dermatol Surg. 1998;23:345-50. 8. Fournier N, Dean S, Barneon G, et al. Nonablative remodeling: clinical, histologic, ultrasound imaging and profilometric evaluation of a 1540 nm Er:glass laser. Dermatol Surg. 2001;27:799-806. 9. Goldberg DJ, Whitworth J. Laser skin resurfacing with the Q-switched Nd:AYG laser. Dermatol Surg. 1997;23:903–7. 10. Kilmer S, Semchyshyn N, Shah G, Fitzpatrick R. A pilot study on the use of a plasma skin regeneration device (Portrait PSR3) in full facial rejuvenation procedures. Lasers Med Sci. 2007. 11. Lee SY, Park KH, Choi JW, Kwon JK, et al. A prospective, randomized, placebocontrolled, double-blinded, and split-face clinical study on LED phototherapy for skin rejuvenation: clinical, profilometric, histologic, ultrastructural, and biochemical evaluations and comparison of three different treatment settings. J Photochem Photobiol B. 2007;88:51-67. 12. Lipper GM, Perez M. Nonablative acne scare reduc-tion after a series of treatments with a short-pulsed 1,064-nm neodymium:YAG laser. Dermatol Surg. 2006;32:998-1006. 13. Manstein D, Herron GS, Sink RK, et al. Fractional photothermolysis: a new concept for cutaneous remodeling using microscopic patterns of thermal injury. Lasers Surg Med. 2004;34(5):426-38. 14. Negishi K, Kushikata N, Takeuchi K, et al. Photorejuvenation by intense pulsed light with objective measurement of skin color in Japanese patients. Dermatol Surg. 2006;32:1380-7. 15. Nikolaou VA, Stratigos AJ, Dover JS. Nonablative skin rejuvenation. J Cosmet Dermatol. 2005;4:301-7.

Nonablative and Subsurface Rejuvenation  293 16. Orringer JS, Voorhees JJ, Hamilton T, Hammerberg C, et al. Dermal matrix remodeling after nonablative laser therapy. J Am Acad Dermatol. 2005;53:77582. 17. Ross EV, Sajben FP, Hsia J, et al. Non ablative skin remodeling: selective dermal heating with mid-infrared laser and contact cooling combination. Lasers Surg Med. 2000;26:186-95. 18. Sadick NS, Weiss R, Kilmer S, Bitter P. Photorejuvenation with intense pulsed light: results of a multicenter study. J Drugs Dermatol. 2004;3(1):41-9. 19. Tanzi EL, Alster TS. Comparison of a 1450-nm diode laser and a 1320-nm Nd:YAG laser in the treatment of atrophic facial scars: a prospective clinical and histologic study. Dermatol Surg. 2004;30:152-7. 20. Tanzi EL, Williams CM, Alster TS. Treatment of facial rhytides with a nonablative 1,450-nm diode laser: a controlled clinical and histological study. Dermatol Surg. 2003;29:124-8. 21. Trelles MA, Allones I, Levy JL, et al. Combined nonablative skin rejuvenation with the 595- and 1450-nm lasers. Dermatol Surg. 2004;30:1292-8. 22. Trelles MA, Allones I, Luna R. Facial rejuvenation with a nonablative 1320 nm Nd:YAG laser: a reliminary clinical and histologic evaluation. Dermatol Surg. 2001;27:111-6.

Chapter

8

Nonsurgical Tightening Simal Soin, Kabir Sardana

Introduction Numerous attempts have been made at counteracting the signs of aging, such as redundant facial and neck skin. In terms of skin laxity specifically, the gold standard of treatment remains rhytidectomy or surgical redraping. However, with the recent advances in technology, conditions that once required major surgical intervention may not always require aggressive intervention. Though nonablative lasers (long pulse 1,064 nm Nd:YAG), and fractional lasers have been used, radiofrequency (RF), infrared, and ultrasound devices are probably better, though the last is yet to find universal acceptance (Table 8.1). Radiofrequency energy works to tighten and lift tissue by delivering heat to dermal structures without adversely affecting the epidermis, thus making it an ideal choice for the nonsurgical face-lift. This energy is produced by an electric current that does not diminish by tissue scattering or absorption by a chromophore. Light-based treatments such as lasers and infrared devices rely on chromophores to produce antiaging effects. Ultrasound waves induce molecules in deep tissue to vibrate, resulting in tissue heating. Like RF energy, the ultrasound waves spare the epidermis Table 8.1 Overview of devices for skin tightening Device

Skin tightening mechanism

ThermaCool TC

Monopolar RF

Accent

Bipolar RF and unipolar RF

Refirme ST

IR and bipolar RF

Polaris WR

Monopolar RF and diode laser (910 nm)

Titan

IR

Lux-IR

Fractional IR

GentleYAG

Long-pulse Nd:YAG

USG

Ulthera

Nonsurgical Tightening  295

and cause selective heating of the deeper tissues. We will focus on minimally invasive, nonablative tissue tightening techniques, including radiofrequency, light and ultrasound-based devices. These devices are not a replacement for surgical procedures and appropriate patient selection remains key to overall satisfaction.

Radiofrequency Therapeutic use of RF technology was first introduced by Bovie and Gushing in the 1920s with the advent of electrocautery. Since then, it has been used for a variety of medical purposes. The discovery that this energy could penetrate deep into the dermis and fibrous septae that support underlying structures via the emission of high-frequency radio waves suggested that this technology could also be used to lift and tighten aging skin. Apart from the three major subtypes, monopolar, bipolar and unipolar RF, some devices that are labeled to be tripolar or multipolar but are variations of the basic three forms of monopolar, bipolar, or unipolar (Table 8.2).

Combination Devices Recently, devices combining RF and light systems were introduced in an attempt to treat both skin laxity and rhytides. These include the ReFirme ST and the Polaris WR systems. ReFirme ST combines broadband IR (700–2,000 nm) and bipolar RF energies (70–120 J/cm3), while the Polaris WR TM system (Syneron Medical Ltd, Israel) combines RF and 900 nm diode laser energies, known as electro-optical synergy or ELOSTM. The optical energy component is used to selectively heat the target tissue. Other energy sources, such as laser or intense pulsed light, can be combined with RF so that a large array of technologies use RF for the ultimate goal of smoothing and tightening of the skin (Table 8.2).

Principles of RF It accomplishes its tissue tightening effects via a unique scheme that utilizes MRF energy at a wavelength of 6 MHz. The energy is applied to the skin via a handpiece that contains a single-use electrode tip. A thin capacitive membrane located on the electrode couples RF to the skin by distributing RF energy (in the form of an electrical current) over a volume of tissue under the surface membrane. A return electrode is placed at a distant site on the body, usually on the back, and an electromagnetic field is created that rapidly alternates from positive to negative charge. As charged molecules pass through the electrical field, heat is generated by the resistance of dermal and subcutaneous tissues to the passage of the electric energy (Fig. 8.1A).

296  Lasers in Dermatological Practice Table 8.2 Comprehensive classification of RF devices* Company and device

Energy specifications

Tips/ electrodes

Comments

Biorad GSD Tech Co, Shenzhen, China

1.15 MHz 1,000 W

3 tips

Continuous cooling; automatic resistance technology; single and continuous mode

Cutera TruSculpt, Brisbane, CA

1 MHz

4” handpiece

Handpiece reads out once optimal temperature is reached of 43–45° C

Ellman Pelleve, Oceanside, NY

4 MHz

4 small handpieces 7.5, 10, 15, 20 mm

Several handpieces for smaller areas. Can use unit as an electrocautery unit also RF + Cautery

Thermage Solta Medical, Hayward, CA

6.78 MHz 400 W

New handpiece (CPT: Comfortable Pulse Technology) with vibrations to improve patient comfort. Pain nerval interceptors get confused and busy (vibrations, cooling, heating)

Accent Family Alma Lasers, Caesarea, Israel

40.68 MHz Up to 300 W

Unipolar+ bipolar+ fractionated RF

Aluma Lumenis Ltd., Yokneam, Israel

40.68 MHZ Up to 300 W

Bipolar and Unilarge handpieces

Apollo-TriPollar Pollogen, Tel Aviv, Israel

1 MHz 50 W

3 handpieces

Aurora SR Syneron/ Candela, San Jose, CA

Up to 25 J/cm2

400–980 nm 580–980 nm 680–980 nm

Elos Plus Syneron/ Candela, San Jose, CA

1–3 HZ Variable

eMatrix Syneron/ Candela, San Jose, CA

Up to 62 mJ/pin

Monopolar Devices

Bipolar RF

FACES technology using functional aspiration

RF + IPL

RF + Infrared light

Matrix of electrodes Fractional RF

Disposable tip, which can prove to be a disadvantage over conventional fractional lasers

Contd...

Nonsurgical Tightening  297 Contd... Company and Device

Energy specifications

Tips/electrodes

Comments

EndyMEd PRO 3 Deep 3 Pole EndyMEd Medical, Caesarea, Israel

1 MHZ 65 W

4 handpieces

3 Deep RF, Handpieces: Skin tightening, body contouring, facial tightening, fractional skin resurfacing

Eprime Syneron/ Candela, San Jose, CA

460 kHZ 84 VRMS

Microneedles

20 degree delivery angle, injected into dermis, fractional skin resurfacing

eTwo Syneron/Candela, San Jose, CA

62 mJ sublative; 100 J/cm3 sublime

Matrix of electrodes

RF + IR

Ray Life Ascepelion

0.5-1 mHz

3 handpieces

Suction and three modes

Reaction Viora, Jersey City, NJ

0.8, 1.7, 2.45 MHz Body 50 W Face 20 W

4 modes- 0.8, 1.7, 2.45 and multichannel

SVC (suction, vacuum, cooling) devices

TiteFx Invasix, Yokneam, Israel

1 MHz 60 W

VelaShape II Syneron/Candela, San Jose, CA

Infrared- Up to 35 W RF Up to 60 W

Velasmooth Syneron/Candela

700–2,000 nm

Venus Concept-8 Circular Poles Venus Freeze, Toronto, ON

RF: 1 MHz Magnetic pulse: 15 Hz RF: up to 150-W Magnetic flux: 15 Gauss

V-Touch Viora, Jersey City, NJ

Bipolar w/suction real time epidermal temperature monitor Handpiece with bipolar Radiofrequency, Infrared laser, Suction

Vsmooth (40 mm × 40 mm) and Vcontour (30 mm × 30 mm) treatment areas

RF/Infrared light with mechanical manipulation Large hand­ piece 8 poles 5 mm apart, dual mode = bipolar magnetic field

Multipolar RF and magnetic pulse

3 hand piece-0.8,1.7, 2.45

SVC (suction, vacuum, cooling) devices

1 handpiece

Unipolar energy to heat fat, bipolar to deliver energy to dermis

Non Contact

Operator independent

Unipolar RF Accent RF Alma Lasers, Caesarea, Israel

40.68 MHz Up to 200 W

Multipolar Devices Vanquish BTL Aesthetics, Prague, CR

*Please contact manufacturers for procedural details

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The device’s energy output is calculated using the following formula: Energy (J) = I2 × z × t where I is current, z is impedance, and t is time in seconds. Energy (J) is created by the impedance ( z ) to electron movement relative to the amount of current ( I ) applied and the total time ( t ) that current is delivered to the tissue. The heat generated is in the temperature range of 65–75°C, which can cause collagen damage, induction of an inflammatory response, thereby resulting in skin lifting and tightening (Fig. 8.1B).

Mode of Action Monopolar RF (Thermage) causes immediate skin tightening through collagen contraction since it heats the collagen in the dermis and fibrous septae in the subcutaneous fat layer. The body interprets the heat as a wound and results in wound healing over a period of time. The wound healing response results in clinical skin tightening. Patients have improvement in

Fig. 8.1A: A diagrammatic overview of the mode of delivery of RF in ‘Thermage’. The electrical current passes through a single electrode in the handpiece to a grounding pad. There is a high density of power close to the electrode’s surface with the potential for deep penetration of tissue heating

Fig. 8.1B: Illustration of the mechanism of collagen remodeling due to RF

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superficial laxity through collagen tightening in the dermis and subcutaneous laxity through tightening of the fibrous septae in the subcutaneous layer. To denature collagen requires heating the tissue to a therapeutic temperature and then keeping it at that temperature. The thermal effect causes the collagen to denaturize and this is transposed into a breaking of the intramolecular bonds. Thus, the molecular structure of collagen is therefore shorter and thicker, which translates into a “tensor effect” that is visible and palpable (skin tightening). The thermal shock produces on the fibroblasts an increase in the production of physiological collagen. It should be emphasized that this very heat can produce problems if too much heat is delivered as the collagen fibrils will denature completely above a critical heat threshold. Conversely, if too little heat is delivered, there will be no tissue response, although it appears that mild thermal injury gives rise to new dermal ground substance and tissue remodeling of photodamaged skin over time. The optimal shrinkage temperature of collagen has been cited as 57–61°C; however, contraction is in actuality determined by a combination of temperature and exposure time. For every 5°C decrease in temperature, a tenfold increase in exposure time is needed to achieve an equivalent amount of collagen contraction. The other main mechanism in skin rejuvenation is a secondary wound healing response that produces dermal remodeling over time. The wound healing response entails activation of fibroblasts to increase deposition of type I collagen and encouraging collagen reorganization into parallel arrays of compact fibrils.

Variables that Affect RF Penetration With radiofrequency technologies, the depth of energy penetration depends on the configuration of the electrodes (i.e. either monopolar or bipolar), type of tissue serving as the conduction medium (i.e. fat, blood, skin), temperature, and the frequency of the electrical current applied. Tissue is made up of multiple layers, which have different resistances to the movement of radiofrequency energy with the dermal tissue with higher impedance being more susceptible to heating. As a thumb rule fat, bone, and dry skin tend to have low conductivities, thus the current tends to flow around these structures rather than through them. Wet skin has a higher electrical conductivity allowing greater penetration of current. This is the reason why improved results are seen with generous amounts of coupling fluid and increased hydration of skin. The structure of each individual’s tissue (dermal thickness, fat thickness, fibrous septae, number and size of adnexal structures) all play a role in determining impedance, heat perception, and total deposited energy despite otherwise equal parameters. Temperature also influences tissue conductivity and the distribution of electrical current. Generally, every 1°C increase in temperature lowers the skin impedance by 2%. Surface cooling will increase resistance to the

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electrical field near the epidermis, driving the radiofrequency current into the tissue and increasing the penetration depth. In addition, target structures that have been pre-warmed with optical energy will, in theory, have greater conductivity, less resistance, and greater selective heating by the radiofrequency current. This is the advantage of hybrid skin-tightening devices that use a combined approach of light and radiofrequency energy together giving synergistic results.

Monopolar Devices Monopolar devices may be delivered in a static or stamped mode in which a short 1- to 2-second cycle is delivered while the handpiece is held in place (Thermage, Solta Medical, Hayward, CA). Alternatively, monopolar RF may be delivered in a dynamic or a continuous pulse with constant rotation of the handpiece (Exilis, BTL, Prague, Czech Republic). In the static, stamped method, a single pulse is delivered; the handpiece is then moved to an adjacent marked area and fired again. This technique is performed for hundreds of pulses until a premarked area is treated. Each pulse is measured for temperature while spray cooling is applied so that a skin temperature of 45o C is not exceeded. With dynamic monopolar RF, the handpiece is continuously moved and specific areas of laxity can be targeted in a relatively short time to a final temperature that is monitored by continuous surface temperature measurements.

Thermage It was the first nonsurgical treatment of periorbital skin laxity and rhytides approved by the FDA and has since become a common technique for treating aging skin (mid-face, cheeks, jaw line, neck, brows, abdomen, legs, and thighs). Thermage has been backed by a strong research and development; and now in its third generation, it has evolved into an extremely sophisticated device. The first generation device, was called thermacool NXT device which employed 400, 600 and 900 REP (Radiofrequency  Energy Pulse) disposable tips with a heat and cooling sensation. The next level is the Thermage CPT, which has some features that make it superior to the previous NXT (Figs 8.2A and B). 1. Redesigned tip, which improves uniformity of heating and increases the total area of skin being effectively heated. 2. Comfort software intended to simulate transcutaneous electrical nerve stimulation (TENS) pain reduction therapy. The TENS therapy for pain management is based on the principle that when electrical current is delivered through the skin, electricity stimulates nerves in the affected

Nonsurgical Tightening  301

Fig. 8.2A: Overview of the ‘Thermage’ device

Fig. 8.2B: A closer look at the components of ‘Thermage’

area and sends signals to the brain that scramble normal pain perception. In effect, the pulsed behavior of the radiofrequency interwoven with cooling bursts improves patient comfort. 3. Vibration based on the gate control theory of pain mitigation. The new thermage CPT handpiece vibrates the tips in order to mitigate discomfort. This Thermage solution here is based on the gate theory by Melzack and Wall, which states that nerve fibers carrying pain to the spinal cord can have their input modified at the spinal cord before transmission to the brain, in this case by the vibration.

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CPT (Comfort Pulse Technology) system came with features that maximized thermal distribution and patient comfort both thereby giving better tightening and contouring (Fig. 8.2C). The third generation thermage employs the same vibration delivery module but with the new total tip which has even more homogeneous three-dimensional skin tightening. These variously sized tips depend mostly on the anatomical area being treated, as larger tips cover a larger area of skin. For example, a 1.5 cm 2 tip should be sufficient for the treatment of the face and neck.

Mechanism of Tissue Heating The mechanism of tissue heating through the use of monopolar radiofrequency   in thermage is unique (Fig. 8.3). As in conventional RF devices, the tissue heat is generated based on the tissue’s natural resistance to the movement of ions with the RF field but the difference lies in the method of coupling the RF to the skin. In thermage, a capacitive coupling membrane is used, which transforms RF to a volumetric tissue heating device rather than a single point heating source as in standard RF devices. This allows energy to be distributed over a three-dimensional volume of dermal tissue while protecting the epidermis (Fig. 8.4). The use of capacitive rather than conductive coupling is important because it allows the energy to be dispersed across a surface to create a zone of tissue heating. With conductive coupling, the energy is concentrated at the tip of the electrode, resulting in increased heating at the contact surface and an increased risk of epidermal injury.

Fig. 8.2C: A comparison of third generation RF with the conventional RF

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Fig. 8.3: A depiction of the depth of penetration of ‘Thermage’

Fig. 8.4: Difference in the heat generation of ‘Thermage’ and other RF machines

Thermage heats tissue more deeply and to higher temperatures than other technologies. Temperatures are higher by 3–4° and deep heating means that the heat dwells longer in the tissue. The treatment protocol involves marking  square grids on the area to be treated so that the requisite amount of overlap be done to ensure complete coverage. The tip delivers monopolar radiofrequency to the lower layers of the skin while protecting the epidermis with cryogenic cooling. With the new total tip technology, thermage tightens and smoothens close to the surface and contours deeply (Figs 8.5A and B). Although, delivering higher energies translates to better results, it is not meant to be an extremely painful or uncomfortable treatment, especially since pain threshold is relative. One may be extremely comfortable with a treatment energy of 4.5 while another may be uncomfortable with an energy

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A

B

Figs 8.5A and B: A customized grid is placed to accurately localize treatment doses

of 3.5. Most treatment protocols across the world follow an algorithm of multiple passes and moderate energies.

Treatment Patient Selection Suitable Candidates: Anyone between the ages of 30 and 60 years is a suitable candidate for the face. For body treatments, anyone from 25 years onward with a loose sagging skin or cellulite is suitable.

Exclusion Criterion Although, Thermage is an extremely safe treatment there are a few absolute and relative contraindications. Absolute ¾¾ Pacemakers ¾¾ Defibrillators ¾¾ Pregnancy ¾¾ History of skin cancer, radiation therapy or metal implant in the treatment area.

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Relative ¾¾ History of diabetes, collagen disorders and congestive heart disease ¾¾ Patients on blood thinners ¾¾ Patients on oral retinoids ¾¾ Recent filler treatments ¾¾ History of neurological disorders. Photography: The importance of photographic documentation in all aesthetic treatments cannot be overemphasized. In Thermage, the results are subtle and subjective improvement cannot always be appreciated by the patient so before and after it is helpful to assess results for both the patient and the doctors. Anesthesia: The protocol dictates that anesthesia is not required since a feedback on the pain sensation is important to minimize risk of burns. Also topical anesthesia does take away from the heat or pain sensation much since the heat penetration is deep.

Procedure Treatment Energy The treating physician must control the amount of radiofrequency energy balancing patient comfort with optimal results since topical anesthesia is not utilized for the procedure. The heat sensation from a single pulse treatment lasts from 2–7 seconds. Treatment parameters vary across clinics and study groups, but in general the previous higher energy, fewer pass practice has now shifted to lower energy and higher pass protocols in order to increase efficiency, tolerability, and safety. Before treatment is initiated, coupling fluid should be applied generously to the area. Then, following the low energy, high pass protocol, RF energy should be applied. Initially, it is helpful for the practitioner to make use of the company-supplied grid that is applied to the skin prior to treatment. The grid shows exactly where the handpiece tip should be placed for adequate treatment (Figs 8.5A and B). As an additional fail-safe, the tip must be in complete contact with the skin or an error message will be displayed. This ensures that the cooling tip will prevent epidermal disruption.

Treatment Areas Thermage is primarily used for skin tightening on the face particularly the jawline, hooding of the eyelids, back of the hands, abdomen, thighs and upper arms. The best results are seen on the face. The results in the neck are suboptimal because the skin of the neck is very thin, so delivery of adequate energy for optimal results is not possible.

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Post-care There is no specific post-care advised following Thermage.

Side Effects Except for being an expensive treatment because of the disposable tip costs involved, a Thermage treatment done in trained hands remains an extremely safe treatment with no side effects whatsoever. Thus, it has managed to stand the test of time and withstand competition with all the multiple technologies available.

Results Initially for the face two passes at 107 J, followed by three or more passes at 83 J was administered. Extra care is given to the neck region, so only 3 or 4 total passes are made at an energy level of 83 J. Moreover, it was noted that multiple treatments yield significantly better results than a single treatment of the nasolabial folds. It is important to continuously assess the patient for signs of discomfort, swelling, and skin tightening during the procedure. Another regimen as proposed by Weiss et al. is a multiple passé regimen with fluences of 74 to 130 J/cm2 using a 1.0-, 1.5-, or 3.0-cm2 tip. In 2006, Dover and colleagues compared the original single-pass, highenergy technique with the updated low-energy, multiple-pass technique using immediate tissue tightening as a real-time end point. With the original treatment algorithm, 26% of patients saw immediate tightening, 54% observed skin tightening at 6 months, and 45% found the procedure overly painful. With the updated protocol, 87% had immediate tissue tightening, 92% had some degree of tightening at 6 months, only 5% found the procedure overly painful, and 94% stated the procedure matched their expectations. According to several authors, a good clinical response remains the most useful cut-off guide for treatment. Generally, improvements are immediately visible and continue for up to 6 months. One of the key features of a Thermage treatment is the preventative aging aspect that is not possible with any injectable treatment. The results can easily last up to 2 years. Quantifiable changes have been seen in brow and superior palpebral crease elevation as well as in the peak angle of the eyebrow and jowl surface area.

Site Specific Improvement 1. Face: The effect is a smoothning and tightening of the skin. There is a improved jawline contouring and sagging of the skin under the chin.

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The Figuer 8.6 reveals softening of wrinkles around the mouth, eyes, and forehead. 2. Eyes: There is a pronounced lifting of the eyelids (Fig. 8.7). Thermage is probably the only nonsurgical procedure that smoothens and tightens the skin and decreases wrinkles and hooding in the eye area without surgery, injections or downtime. Treatment results are younger looking, more lifted eyes that look less tired. There is reduction in under eye bulges and improved laxity. Eyes are protected during the procedure

Fig. 8.6: A marked improvement in the forehead lines

Fig. 8.7: A pre- and postoperative photograph showing the marked improvement in wrinkles around the eyes

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with small, plastic eye shields. Suitable candidates for thermage for eyes are those with moderate hooding, crow’s feet, eyelid laxity and/or under-eye bags. 3. Body: Thermage for the body procedures improve skin tone and texture while effectively smoothing, tightening and contouring skin for an overall naturally younger looking appearance. With little to no downtime, thermage for the body treatments tighten and renew the skin’s collagen deep down, through all three layers of skin—the epidermis, dermis and subcutaneous (fat) layer. The treatment is ideal for arms, abdomen (commonly used  post-pregnancy and after liposuction or weight loss), and thighs. It remains the nonsurgical treatment of choice for loose lax skin on the body areas (Fig. 8.8).

Cellulite Thermage is FDA approved for cellulite. Although it is widely used with a separate cellulite tip, in the authors experience the result’s are variable.

Acne In addition to skin tightening, monopolar RF has also been used to treat active cystic acne to inhibit sebaceous activity and promote dermal contouring. A study (Ruiz-Esparza J 2003) including 22 patients with moderate to severe active cystic acne reported improvement with the use of stamped monopolar RF. Patients were treated in 1 to 3 sessions using 65 to 103 J/cm2. A 75% reduction in the active acne lesion count was seen in 92% of patients, and a 25% to 50% reduction occurred in 9% of patients. Often a decrease in active lesions was accompanied by the improvement of underlying scarring. These results have not been duplicated in other studies.

Fig. 8.8 : Tightening of the loose skin on the abdomen

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EXILIS Elite Device A novel RF dynamic monopolar device, the Exilis, is a device that combines focused monopolar RF delivery with several built-in safety features, including Peltier cooling. The Exilis system delivers the energy through two different hand applicators, one designed for the face and one designed for the body. The goal of treatment is to raise the surface temperature to 40°C to 42°C for 4 to 5 minutes for each region treated. When this temperature is reached, patients feel a comfortably warm sensation. The handpiece is in continuous motion so that the areas of skin with the most laxity can be specifically targeted. This treatment has been termed ‘dynamic monopolar RF’. Additionally, Peltier cooling can be adjusted up or down to allow targeting of skin or subcutaneous tissue. For example, to drive heating more deeply, the skin is cooled and protected allowing heat to reach into subcutaneous fat. Alternatively, to get the maximum effect on skin laxity, cooling is turned off and heating of the skin occurs very quickly with a minimal effect on subcutaneous fat.

Bipolar RF In this method, the RF travels from the positive to the negative pole, which is typically between 2 poles built into the handpiece. With a specific distance between the electrodes, the depth of penetration and heating is predetermined by the spacing of the electrodes and is typically confined to within 1 to 4 mm of the skin surface (Fig. 8.9). It is commonly stated that the depth of penetration is half the distance between the electrodes, but there is very little evidence to support this assertion. The ‘Raylife’ radiofrequency is bipolar parallel that uses a handpiece that has two electrodes positioned inside it. The addition of the vacuum function generates continuous or pulsed suction of tissue with the passage of electromagnetic waves only on the selected target area. These waves pass from one electrode to another and when they cross the dermis they activate the mechanism of denaturizing the collagen. The Coolstar, water cooling function on the tissue, determines a protective action on the epidermis making the treatment extremely pleasant and safe (Fig. 8.10). Bipolar RF is not as penetrating as monopolar RF, so it is not as painful but is often combined with another energy source to increase its efficacy. There are multiple variations of the bipolar RF concept and these are as follows (Table 8.2): 1. Fractional or fractionated RF constructed of mini-bipolar electrodes (eMatrix, e2, Syneron/Candela, Wayland, MA). 2. Bipolar insulated needle electrodes, which are mechanically inserted into the dermis (ePrime, Syneron/Candela).

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Fig. 8.9: Illustration of bipolar radiofrequency, ‘L’ handpiece (inactive and active) (Asclepion Laser Technologies, GmbH)

Fig. 8.10: Advantages of bipolar RF (Asclepion Laser Technologies, GmbH)

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3. Bipolar RF combined with other modalities, including diode laser or intense pulsed light (Polaris, Aurora, and Velasmooth, Syneron/ Candela). 4. Multiple bipolar electrodes at different distances apart firing sequentially to achieve different depths (EndyMed PRO, EndyMedMedical Ltd, Caesarea, Israel). 5. Bipolar RF with vacuum to control depth of penetration called functional aspiration controlled electrothermal stimulation (Aluma, Lumenis Inc, San Jose, CA). 6. Other variations include magnetic pulse and combinations with IR. The major disadvantage to bipolar radiofrequency is that the energy does not penetrate very deep into the skin. Also, it is believed that bipolar radiofrequency is unable to produce a uniform, volumetric heating response comparable to monopolar radiofrequency. When bipolar radiofrequency devices are combined with other light-based technologies, which is the case in most situations, it is then difficult to assess exactly how large a role bipolar radiofrequency plays in the clinical outcomes of such treatments.

Aluma The Aluma is a bipolar RF plus vacuum device that is composed of an RF generator, a handpiece, and a tip with 2 parallel electrodes. When the hand piece with the tip is placed perpendicular to the surface of the skin, the system produces a vacuum, which suctions a small area of skin. The skin becomes a U-shaped area with epidermis on both sides and the dermis and connective tissue in the middle. The design is to allow the energy emitted to reach the middle and deep dermis. This is also called as ‘FACES’ (functional aspiration controlled electro­ thermal stimulation) technology. Non-target structures such as muscle, fascia, and bone are avoided. The theory is that this may help to overcome the depth limitations inherent in bipolar radiofrequency technology by bringing the target tissue closer to the electrodes. Less overall energy may also be required for an effective treatment. It has also been hypothesized that increased blood flow and mechanical stress of fibroblasts from the vacuum suction may lead to increased collagen formation. Vacuum technology has the added benefit of helping to reduce procedure discomfort. In a pilot study of 46 adults, Gold found significant improvements in skin texture, indicating a shift from moderate to mild elastosis. There was a shortterm tightening effect due to collagen contraction followed by a gradual, longterm improvement due to the wound healing response and neocollagenesis. Importantly although subjects were generally pleased with the treatment outcome, their satisfaction levels declined somewhat during the follow-up period.

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eMatrix Fractional RF is another form of bipolar RF delivery with mini-electrodes. The concept is that RF is omnidirectional so that dots of RF spread out from the point of contact in comparison with laser in which the energy is attenuated in a sharp fashion in interaction with tissue. Fractional RF has been used mainly for skin rejuvenation. Less than 1-mm thermal injuries are formed in a patterned fractional array directly to the reticular dermis. The area directly in contact with and below the array of microneedles or electrodes is selectively heated while the areas between the targeted areas are left intact.

ELOS Combined Electrical and Optical Energy The basic principle is that these skin-tightening devices combines radio­ frequency energy with optical energy from laser or light sources. The currently available combined electrical and optical energy devices include the Galaxy, Aurora, Polaris, and ReFirme systems (Syneron Medical Ltd, Yokneam, Israel). They have a theoretical advantage of acting synergistically to generate heat. As discussed above when the target structures have been pre-warmed with optical energy they will have greater conductivity, less resistance, and greater selective heating by the radiofrequency current. No grounding pad is required as the current flows between the electrodes rather than throughout the remainder of the body as with monopolar systems. There is a potential side effect in “tissue arcing”, which results in tissue burns and possible scar formation. Proper technique will help avoid the issue as arcing has been associated with the handpiece not being properly placed in contact with the skin. The technology has been used in hair removal, wrinkle reduction, skin tightening, and the treatment of both pigment and vascular disorders. The premise is that less radiofrequency energy is ultimately needed for proper collagen denaturation and remodeling. The ReFirme ST system produces only mild improvement of facial laxity in Asians (Yu et al.) without serious adverse effects, but still meets high patient expectations. More enduring studies are necessary to determine the longterm tissue tightening effects of this device. A study by Doshi and Alster in 20 patients (skin phototypes I–III) with mild-to-moderate rhytides and skin laxity with the Polaris WR combination RF and diode laser device found only modest improvement of facial rhytides.

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Hybrid Monopolar and Bipolar Radiofrequency The first system to combine monopolar and bipolar radiofrequency in one device was the Accent (Alma Lasers, Buffalo Grove, IL). The theory behind using both types of radiofrequency is to deliver different depths of current to the skin. The bipolar electrode handpiece allows for more superficial, localized (non-volumetric) heating based on tissue resistance to the radiofrequency conductive current. The monopolar electrode handpiece targets deeper, volumetric heating via the rotational movement of water molecules in the alternating current of the electromagnetic field. Therefore, the monopolar handpiece is used to treat the forehead, cheeks, jawline, and neck while the bipolar handpiece is used to treat the glabella, lateral periorbital area, upper lip and chin, and leg. In 2007, Friedman and Gilead studied this device and found that although the Accent system is effective in the treatment of wrinkles and lax skin, younger individuals may see a greater benefit.

Pelleve Device (Ellman International, Oceanside, NY) This has a dual monopolar and bipolar radiofrequency-based surgical unit normally used for tissue cutting and coagulation to make it suitable for skintightening procedures. The system works with the use of reusable probes that are plugged into the system and applied over the skin in a circular pattern to heat the subdermal tissue. A chilled coupling gel is used to assure proper coupling between the electrode and the patient and to help protect the epidermis. As with other skin-tightening devices, the gentle heating induces collagen denaturation, contraction, and subsequent synthesis. Repeat treatments have been shown to improve the appearance of wrinkles and skin laxity, but results are somewhat limited due to the discrete amount of energy applied. Early protocols recommended 8-weekly treatments for best results, but the treatment paradigm has since been revised to two treatments spaced 1 month apart, with some patients requiring an additional treatment.

Unipolar RF Another form of delivery is unipolar in which there is one electrode, no grounding pad, and a large field of RF emitted in an omnidirectional field around the single electrode. This form is analogous to a radio tower broadcasting signals in all directions.

The Accent (Alma Lasers, Inc, Ft Lauderdale, FL) The Accent RF system is designed for continuous skin contact using two handpieces: the unipolar to deliver RF energy to the subcutaneous adipose

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tissue for volumetric heating and the bipolar to deliver RF energy to the dermis for nonvolumetric heating. It uses both unipolar and bipolar RF and delivers different depths of RF current to the skin, theoretically bipolar for more superficial heating and unipolar for deeper dermal heating. Several clinical trials describe its use in reducing the appearance of cellulite and its effects on tissue tightening.

Multipolar Noncontact RF Device Vanquish (BTL Aesthetics, Prague, Czech Republic) Previously discussed RF devices are operator dependent. This device has been designed for a contactless deep-tissue thermal-energy application. The applicator-generator circuitry is engineered to selectively deliver the energy to the tissue layer with specific impedance. This high-frequency system focuses energy specifically into the adipose tissue, while limiting delivery to the epidermis, dermis, and muscles. Animal studies have shown a 70% fat reduction in the treated abdominal area. Proportionate results have been seen in humans also.

Conclusion There are certain important rules that determine results with RF: 1. Though the early results are marked, the late results are difficult to judge objectively. This makes an excellent photographic documentation essential. This is because delayed neocollagenesis and long-term woundhealing response is an important aspect of RF therapy and subjects may have difficulty, accurately remembering the exact condition of their skin pre-treatment, particularly when 6 or more months have passed. 2. Young patients respond best to therapy. This can be partly due to the replacement of heat-labile collagen bonds by irreducible multivalent cross-links as patients age, making older skin less susceptible to heatinduced tissue tightening.

Infrared light devices 1. Broadband infrared light in the range of 800 to 1,800 nm, has also been utilized for nonablative tissue tightening. The first such light-based system was the Titan (Cutera, Brisbane, CA). It utilizes light energy in the range of 1,100 to 1,800 nm to target water as a chromophore, causing collagen denaturation and ultimately collagen remodeling and tissue tightening. Studies on this device have shown that minimal to excellent results can be obtained with immediate skin tightening, but clinical skin tightening does not always correlate with immediate positive

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histological findings. This is explained by the fact that full clinical effect may take weeks or months to be demonstrated owing to a secondary wound healing response. (Ruiz-Esparza  J, 2006 and Zelickson  B). A lower fluence range of 30–40 J/cm2, 2–3 treatments, 1–2 passes, and extra passes on areas that need immediate contraction or along vector lines yielded best results. 2. The StarLux IR (Palomar Medical Technologies, Burlington, MA) delivers fractionated energy through the handpiece of the device at a wavelength range of 850 to 1,350 nm, which also targets water as the principal chromophore. Multiple treatments are required for optimal results. 3. The SkinTyte device (Sciton, Palo Alto, CA) utilizes light at a wavelength range of 800 to 1,400 nm. 4. Other laser wavelengths that have been used for tissue tightening include the 1,064 nm and 1,320 nm wavelengths. The chromophores for the 1,064 nm wavelength, in decreasing order, are melanin, hemoglobin and water, and the primary chromophore for the 1,320 nm wavelength is water. Though studies (Taylor and Prokopenko, 2005) have shown results better than a monopolar radiofrequency system, some authors point out that (Key, 2007) that the 1,064 nm improves the lower face, more than the upper face. The mild improvemnet noted by Trelles (2001) using a 1,320 nm laser system shows that combining laser treatment with parallel epidermal treatment may yield better results and achieve higher patient satisfaction.

Ultrasound devices High-intensity focused ultrasound (HIFU) is the most recent player to enter the skin-tightening technology realm. The basic concept being that the intense ultrasound field vibrates tissue thus the consequent friction created between molecules causes them to absorb mechanical energy and leading to secondary generation of heat. Intense focused ultrasound for skin-tightening applications uses short, millisecond pulses with a frequency in the megahertz (MHz) domain, rather than kilohertz (kHz) as is used in traditional HIFU, to avoid cavitational processes. Intense focused ultrasound also uses significantly lower energies than traditional HIFU, 0.5–10 J versus 100 J, which allows thermal tissue changes without gross necrosis. The main advantage to focused ultrasound is the potential for greater depth of skin changes than other technologies with the added benefit of precisely controlled, focal tissue injury. Ultrasound energy is able to target deeper structures in a select, to ocused fashion without secondary scatter and absorption in the dermis and epidermis. The first intense focused ultrasound

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device on the market is the Ulthera system Ulthera Inc., Mesa, AZ) and is covered in detail in a following chapter.

Conclusion Nonsurgical skin tightening is best suited for patients with mild-to-moderate laxity. Thus, cases with laxity of the aponeurotic system are not candidates for this therapy. Combination therapy is the ideal approach in most cases. A suggested approach in a patient desirous of a brow lift and a jawline definition may be a combination of botox to the orbicularis oculi and platysma in addition to skin tightening. Fillers can be used in the mid face, brow/temples and jawline. The key to success is ideal patient selection and management of expectations. As there remains a lack of an FDA-approved method for measuring skin tightening, most of the results are based on before and after photos. A few assessment scales are given in Table 8.3 and 8.4, which can help the clinician objectively assess results. Large-scale randomized controlled trials are still necessary to determine optimal treatment parameters for most of the newer bipolar devices and USG.

Table 8.3 The Fitzpatrick Wrinkle Classification System Class

Wrinkling

Score

Degree of elastosis

I

Fine wrinkles

1–3

Mild (fine textural changes with subtly accentuated skin lines)

II

1.Fine-to-moderate depth wrinkles 2. Moderate number of lines

4–6

Moderate (distinct popular elastosis [individual papules with yellow translucency under direct lighting] and dyschromia)

III

1. Fine-to-deep Wrinkles 2. Numerous lines 3. With or without redundant skin folds

7–9

Severe (multipapular and confluent elastosis [thickened yellow and pallid] approaching or consistent with cutis rhomboidalis)

Table 8.4 The Leal Laxity Classification System Laxity

Description

A

Superficial laxity limited to the skin

B

Structural laxity involving subcutaneous tissue

AB

Combined superficial and structural laxity

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Bibliography 1. Abraham MT, Chiang SK, Keller GS, Rawnsley JD, Blackwell KE, Elashoff DA. Clinical evaluation of non-ablative radiofrequency facial rejuvenation. J Cosmet Laser Ther. 2004;6:136-44 2. Alster TS, Tanzi E. Improvement of neck and cheek laxity with a non-ablative radiofrequency device; a lifting experience. Dermatol Surg. 2004;30:503-7. 3. Beasley KL, Weiss RA. Radiofrequency in cosmetic dermatology. Dermatol Clin. 2014;32(1):79-90. 4. Biesman BS, Baker SS, Carruthers J, Leal Silva H, Holloman EL. Monopolar radiofrequency treatment of human eyelids: A prospective, multicenter, efficacy trial. Lasers Surg Med. 2006;38:890-8. 5. Bogle MA, Kaminer MS. Non surgical Skin tightening. In: Lasers and Lights: Procedures in Cosmetic Dermatology, 3rd edition by Hruza GJ and Avram MM. 2013. 6. Doshi SN, Alster TS. Combination radiofrequency and diode laser for treatment of facial rhytides and skin laxity. J Cosmet Laser Ther. 2005;7(1):11-5. 7. Dover JS, Zelickson B and the 14-Physician multispecialty consensus panel: Results of a survey of 5,700 patient monopolar radiofrequency facial skin tightening treatments: assessment of a low-energy multiple-pass technique leading to a clinical end point algorithm. Dermatologic Surgery. 2007;33:900-7. 8. Fitzpatrick RE, Geronemus RG, Goldberg DJ, Kaminer MS, Kilmer SL, RuizEsparza J. Multicenter study of non-invasive radiofrequency for periorbital tissue tightening. Lasers Surg Med. In press 9. Friedman DJ, Gilead LT. The use of hybrid radiofrequency device for the treatment of rhytides and lax skin. Dermatol Surg. 2007;33(5):543-51. 10. Gold MH. Update on tissue tightening. Journal of Clinical and Aesthetic. Dermatology. 2010;3:36-41. 11. Key DJ. Single-treatment skin tightening by RF and long-pulsed, 1064-nm Nd : YAG laser compared. Lasers in Surgery and Medicine. 2007;2:16-75. 12. Lolis MS, Goldberg DJ. Radiofrequency in cosmetic dermatology: a review. Dermatol Surg. 2012;38(11):1765-76. 13. Narins DJ, Narins RS. Non–surgical radiofrequency facelift. J Drugs Dermatol. 2003;2:495-500. 14. Ruiz-Esparza J, Gomez JB. Nonablative radiofrequency for active acne vulgaris: the use of deep dermal heat in the treatment of moderate to severe active acne vulgaris (thermotherapy): a report of 22 patients. Dermatol Surg. 2003;29(4): 333-9. 15. Ruiz-Esparza J, Gomez JB. The medical facelift: a non-invasive, non-surgical approach to tissue tightening in facial skin using non-ablative radiofrequency. Dermatol Surg. 2003;29:325-32. 16. Ruiz-Esparza J. Painless, nonablative, immediate skin contraction induced by low-fluence irradiation with new infrared device: a report of 25 patients. Dermatologic Surgery. 2006;32(5):601-10. 17. Taylor MB, Prokopenko I Split-face comparison of RF versus long-pulse Nd:YAG treatment of facial laxity. Journal of Cosmetic and Laser Therapy. 2006;8:17-12.

318  Lasers in Dermatological Practice 18. Trelles MA, Allones I, Luna R. Facial rejuvenation with a nonablative 1320-nm Nd:YAG laser: a preliminary clinical and histologic evaluation. Dermatologic Surgery. 2001;27:111-6. 19. Wall MS, Deng XH, Torzilli PA, Doty SB, O’Brien SJ, Warren RF. Thermal modification of collagen. J Shoulder Elbow Surg. 1993;8:339-44. 20. Weiss RA, Weiss MA, Munavalli G, Beasley KL. Monopolar radiofrequency facial tightening: a retrospective analysis of efficacy and safety in over 600 treatments. J Drugs Dermatol. 2006;5(8):707-12. 21. Yu CS, Yeung CK, Shek SY, et al. Combined infrared light and bipolar radiofrequency for skin tightening in Asians. Lasers Surg Med. 2007;39:471-5. 22. Zelickson B, Ross V, Kist D, et al. Ultrastructural effects of an infrared handpiece on forehead and abdominal skin. Dermatologic Surgery. 2006;32:897-901.

CHAPTER

9

Aesthetic Intense Focused Ultrasound (IFUS): Clinical Perspective on Fitzpatrick Skin Types III–VI Shahin S Nooreyezdan, Inder Raj S Makin

INTRODUCTION During the past few decades, surgical intervention has been the mainstay for managing skin laxity of the face and neck as well as attaining a favorable contoured proportion of the abdomen and torso. There is a greater awareness for aesthetic maintenance and demand for attaining a more proportionate and youthful appearance among various societies worldwide, based on an increasing life expectancy, socioeconomic status, and persistent media coverage on the need for favorable aesthetic and cosmetic outcomes. This need for reducing tissue laxity on the face, neck and other exposed body skin surfaces as well as a proportionally contoured body exists in all ethnic groups. A growing portion of the target population is averse to direct surgical interventions and related greater risk and downtime, hence, more patients opt for undergoing minimally- or non-invasive procedures. Prospective cases are willing to adopt techniques that require repeat visits, and accept clinical outcomes that are more modest as compared to the surgical procedures. Non-invasive or minimally-invasive aesthetic interventions most often are performed by energy-based systems, such as laser or other photonbased techniques, radiofrequency (RF) current-based devices, or intense focused ultrasound (IFUS) based modalities. Each of these techniques is capable of attaining a certain range of skin and superficial tissue response, and by extension clinical effect, based on biophysical characteristics of the specific energy modality. Attaining a successful clinical outcome to mitigate a particular clinical presentation is dependent on matching the right energy source to the tissue. This chapter will discuss the role of IFUS systems that are presently deployed in the management of dermatologic and aesthetic presentations. The organization of this chapter is as follows in Box 9.1.

PHYSICS AND INSTRUMENTATION Ultrasound is a form of mechanical energy, which propagates from the source outwards through any medium, such as water, tissue, or air, as a wave. This

320  Lasers in Dermatological Practice Box 9.1

Summary points of IFUS

• Description of the physical concept for focused ultrasound beams, relevant biophysics, and instrumentation • Clinical application of IFUS for aesthetic and plastic surgery application, and related tissue effects • Clinical results following use of IFUS, with emphasis on treatment of cases with skin of color (Fitzpatrick skin types III–VI) • Summary and conclusion

propagation is similar to the rippling of “peaks and troughs” one observes when a stone is dropped in a quiescent pond. Ultrasound (when sound is operating at greater than 20,000 cycles per second), has the characteristics of its wavelength, intensity, scattering, and absorption leading to localized heating or dispersive changes in the medium, due to frictional and relaxational molecular phenomena. Similar to photon energy, ultrasound energy has an inverse relationship between frequency and wavelength. For example, at frequencies of interest (1–10 MHz), in the present context of the discussion, the wavelength of the propagating energy in tissue can vary from 1.5 – 0.15 mm. For human tissue applications, ultrasound energy can therefore, be “directed” or focused to a very small spatial zone, as shown in Figure 9.1 (ter Haar, Miller et al.). For dermatologic and aesthetic applications, this ultrasound energy concentration can be attained up to several millimeters in the body. This characteristic of focused ultrasound is unique compared to lasers and other photon-based energy modalities, which scatter very rapidly within the first millimeter of skin and dermal tissue. Further, in the radiofrequency-based (RF) energy sources, which are widespread in aesthetic applications, the energy modality is diffused due to the long (several centimeters to meters) wavelength, hence cannot be “focused” in the body. Due to the primary physics of the modality, RF energy dissipates within tissue from the source plane outwards, being maximum at-source, decaying rapidly as it progresses deep in the tissue. The aesthetic practitioner is familiar with ultrasound devices in practice, however, mainly as minimally invasive devices for ultrasound-assisted liposuction (UAL) or diathermy-like external ultrasound-assisted liposuction (EXT) (Rohrich RJ et al.) The UAL devices operate at kilohertz (kHz) energy levels are minimally invasive, relying on local tissue effects. The EXT systems operate at about 1–3 MHz, radiating continuously with an unfocused geometry, at relatively low ultrasound intensities (0.5–3 W/cm2). The highly focused systems described in the present section are distinct from the UAL and EXT devices. Focused ultrasound devices operating at MHz frequency that are capable of selectively coagulating tissue or non-thermally damaging tissue have been used consistently over the past decades for various clinical applications. Several extensive reviews have been published, (ter Haar GT, Miller DL et

IFUS: Clinical Perspective on Fitzpatrick Skin Types III–VI   321

Fig. 9.1: Schematic represantaion of a generalized focused beam for aesthetic applications. The focal spot can concentrate energy 1–20 mm deep from the skin surface

al, Kennedy JE et al, ter Haar GT, Coussios C), however, most of the focused ultrasound devices aim to debulk the tissue in the target organ. The first reported application for non-invasive aesthetic procedures were developed in the past 10–12 years. Based on the precise procedures developed, i.e., lipolysis, or skin tightening applications, the technologies implemented varied. Non-invasive body contouring or lipoplasty using ultrasound was the initial goal and laid the foundations for two devices, the Liposonix and Ultrashape systems, respectively. The goal of each of these concepts was to coagulate or irreversibly damage subcutaneous fat tissue in the abdominal region, flanks, and thigh regions, at 10–20 mm depth. Further, the delivery of energy from these focused high power ultrasound sources is intended to “blanket” the band of tissue around the 10–15 mm depth, such that a substantive (50–500 cc) of tissue was lysed with ultrasound energy. Both these requirements, can be fulfilled by large dimensioned (25 mm and above) ultrasound transducer sources, with high outputs (order of 100 W acoustic power), which operate between 0.5–2.5 MHz. Technical details and configuration for the Liposonix and Ultrashape systems have been described in the scientific literature extensively (Jewell and Desilets CS, Fatemi A, Brown SA et al., Teitelbaum S et al., Coleman KM et al.). One key difference between the Liposonix and Ultrashape techniques is that the focused field from Liposonix source is at approximately 2 MHz frequency, which thermally coagulates the tissue at the focal zone as energy is selectively absorbed in that region. The Ultrashape design generated focused ultrasound energy at less than 1 MHz (~0.25 MHz),

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and multiple short pulses much shorter than 1 second (milliseconds). At this low frequency and pulsing regime, it is claimed that the focal tissue lyses results primarily from non-thermal mechanisms, such as rapidly growing and collapsing bubbles (cavitational) phenomena (Brown et al.). Both devices have since been used in the clinic worldwide on an experimental and routine basis, whereas Liposonix has received FDA approval for non-invasive waist circumference reduction. In the treatment of skin laxity by tightening and lifting dermal and subdermal skin tissue on the face, neck and upper body, a different, more selective approach is used in the Ultherapy procedure. Ultherapy has been approved to lift skin above the eyebrow, on the neck and under the chin. In contrast to an approach for attaining tissue lysis through heat or cavitational mechanisms, the highly focused transducer configurations with Ultherapy create a line of discrete thermal coagulation points (TCP) at a predefined depth. These zones of thermal coagulation are interspersed by adequate normal unexposed tissue. The Ulthera system handpiece can accommodate a series of limited use transducers which enable the user to deliver microfocused ultrasound energy at various depths, such as 4.5, 3.0, or 1.5 mm. Based on the depth of operation, TCP size, and treatment safety, each probe is configured to operate at specific frequencies (4, 7, or 10 MHz). The nominal size of each TCP is on the order of 1 mm3 or less, hence the terminology “microfocused.” The Figure 9.2 shows the actual beam measured for a 4 MHz MFU transducer (Fig. 9.2A). The panel (Fig. 9.2B) is the corresponding numerically simulated thermal coagulation zone, while the actual thermal zone achieved at ~4 mm depth in porcine skin tissue in vivo is shown in (Fig. 9.2C). These results provide a good comparison between instrumentation testing, numerical prediction and preclinical studies. The Ulthera concept for microfocused ultrasound is shown in Figure 9.3, whereby TCPs at 4.5 and 3 mm depths in porcine tissue are attained. An additional functional feature of the Ulthera system is the integrated quasi-realtime ultrasound imaging for the clinician as the energy is being delivered in skin tissue. The integrated imaging capability combined with highly-focused therapeutic ultrasound has been coined as Microfocused Ultrasound-Visualization (MFU-V), with FDAclearance to visualize dermal and subdermal tissue. Details and specifics of instrumentation design and validation have been reported in the literature (Laubach HJ, White WM, Gliklich RE, Alam M). The aesthetic clinician is being offered an ever-increasing list of energybased technologies, promising to provide non-invasive aesthetic solutions for skin and subcutaneous tissue. The probability of an appropriate match of energy source to a particular aesthetic application is based on the user attaining an understanding of energy-tissue interaction of various energy modalities. The Figure 9.4 shows a schematic of physically realistic energy profile of three energy modalities, laser – RF and – microfocused ultrasound following exposure to skin tissue. If the goal is to attain coagulative tissue

IFUS: Clinical Perspective on Fitzpatrick Skin Types III–VI   323

Figs 9.2A to C: (A) Excellent comparison of microfocused beam spot; (B), The numerically predicted thermal damage zone; (C) The actual achieved porcine tissue coagulation, under gross-sectioning (vital staining). The single focal spot is a fraction of a rice grain in dimensions (With permission from Ulthera, Inc., USA)

A

B

Figs 9.3A and B: Gross-section (vital stain) of porcine tissue exposed with 4.5 mm and 3 mm depth transducers. Thermal coagulation zones can be placed at predetermined planes below skin surface, while maintaining adequate intervening healthy tissue (With permission from Ulthera, Inc., USA)

changes superficially (sub-millimeter depth), then laser energy is possibly the most appropriate modality. Radiofrequency energy systems provide a relatively diffused and progressively decreasing energy density profile, and is possibly most appropriate to attain a generalized heating of skin tissue. An RF source can achieve tissue coagulation only in selected zones, when these zones of high impedance to RF energy are coincidently in the path of high electrical impedance for the field, not necessarily controllable by the

324  Lasers in Dermatological Practice

Fig. 9.4: Schematic representation of laser, RF, and MFU biophysical capabilities to attain tissue coagulation in skin tissue. The physically realistic temperature profiles are mapped over therapeutically relevant skin layers (With permission from Ulthera, Inc., USA)

operator. By selecting specific probe types, the microfocused systems enable attaining precise and predictable TCPs at specified depth planes, based on the operator’s clinical requirements. Eventually each energy modality has its merits and limitations, however, an understanding of physical characteristics of a particular energy sources maximizes the possibility to deliver optimal clinical treatment (Dobke MK et al.).

TISSUE EFFECT AND CLINICAL APPLICATION The goal of non-invasive focused ultrasound treatments, whether for body contouring or for skin tightening and tissue lifting is to concentrate energy at the plane of clinical interest while sparing the skin surface and intervening tissue. The Liposonix device is applied to abdominal skin and flanks for patients with mild to moderate subcutaneous fat deposition such that about 2.5 cm of adipose tissue can be measured using a pinch-test. The abdomen and the flanks are divided into nine regions 2.5 × 2.5 cm in dimensions, and 1–3 passes of exposures totaling 109–271 J/cm2 were delivered using a 2 MHz focused applicator, such that a band of subcutaneous region 10–20 mm below the skin surface is targeted. Tissue thermal coagulation results at the aspect ratio of the ellipsoidal profile of the focal zone of the 2 MHz transducer (see Fig. 9.1), whereby these zones are longitudinally stacked next to each other to create a circumferential band of thermally necrosed adipose tissue along the patient’s girth. Details of the tissue effect with acute gross pathology and histology are described by Jewell, Desiletz, Gadsden EI and Fatemi et al. Clinical results following Liposonix HIFU procedures for body contouring have been reported in multicenter human subject studies (Fatemi et al.,

IFUS: Clinical Perspective on Fitzpatrick Skin Types III–VI   325

Jewell et al., 2011). Clinical endpoints in these studies, showed a measurable reduction in girth, controlled photographic evidence of body contour improvement and a subjective patient satisfaction, assessment of treatment outcome. Side effects and complications were documented for the test cases. Photographic and quantitative assessments were recorded at 4, 8, and 12 weeks post-procedure. Body-contouring procedures using Liposonix technique has evolved over the past years. The target patient population is one having mild to moderate subcutaneous adipose tissue accumulation, and one averse to any invasive procedures. The current protocols are evolving towards 1–3 treatment sessions at much lower energy density levels (~45 J/cm2), compared to the settings from initial studies. Pain, bruising, edema, and paresthsias as well as only subtle outcomes are existing issues with the technology.

ULTHERA Achieving skin tissue tightening and lifting of sagging tissue has been accomplished successfully by implementing the Ultherapy MFU technique under integrated quasi-continuous ultrasound visualization. This approach was initially demonstrated in controlled clinical studies, to be safe and efficacious in treating the face and upper neck, while lifting the eyebrow height in >80% cases (reviewer masked) (Gliklich RE and Alam et al.) The multiple TCPs with intervening normal subcutaneous tissue result in the selective tissue necrosis followed by acute tissue shrinkage and regeneration of new collagen. Ultherapy procedure is approved by US-FDA for the indications: improvement of eyebrow height, and non-invasively lift lax tissue on the neck and the submental region. The present treatment guidelines for the face and upper neck consist of the use of a family of four transducers: 4 MHz, 4.5 mm; 7 MHz, 3.0 mm; 7 MHz, 4.5 mm; and 7 MHz, 3.0 mm (narrow). These transducers enable the clinician to place a series of up to 800 lines per a manufacturer recommended protocol, in two planes—4.5 mm and 3.0 mm depth. Depending on the transducer selected, each line consists of 15–22 TCPs, which are places at the specified depth subcutaneously. The probes are depicted in Figure 9.5. The user interface is intuitive, and the clinician is guided through selection of treatment region as well as number of lines of treatment with a specified transducer in that region. Through interchangeable transducers, the same system can be used for thermally coagulating focal zones at selected depths in the tissue, under simultaneous imaging monitoring. Patient comfort and minimizing intraprocedural pain are the key bases for safety with the Ultherapy procedure. The initial treatment guidelines for face and neck was a placement of up to 500 lines, with 4 MHz, 4.5 mm and 7 MHz, 3.0 mm defaulting at 1.2 J, and 0.45 J energy respectively “5+” guidelines).The

326  Lasers in Dermatological Practice

A

B

Figs 9.5A and B: (A) The interactive touchscreen user interface; (B) Photograph of the Ulthera system and transducers (With permission from Ulthera, Inc., USA)

present guidelines recommend the delivery of 800 lines on the face and neck, with 0.9 J (4 MHz, 4.5 mm) and 0.3 J (7 MHz, 3.0 mm), respectively. Patient outcomes were comparable for the two treatment regimens, while the pain scores recorded were lower by an average of 1.5 points on a 10 point pain scale (statistically significant) (Ulthera white paper). The Figure 9.6 illustrates the treatment plan with the current “Amplify” guidelines from Ulthera to adequately treat the face and upper neck. The depth of TCP placement in the pre-auricular, and mid-face region can reach the level of superficial musculoaponeurotic system (SMAS), thereby capable of robust tissue shrinkage and lifting (White, Gliklich, Day, Dobke, MacGregor, Har-Shai Y). There is no need for a local anesthetic, since the delivery of energy is deep in the subcutaneous region (Alam et al). As a firstline of intraoperative pain management, a loading dose of up to 800 mg Ibuprofen, 60 – 90 minutes prior to the Ultherapy procedure should be adequate, however, this regimen can be modified on a patient-to-patient basis (MacGregor et al). Prior to procedure, a detailed case assessment is recommended, as well as a consult to understand and establish the patient’s expectations. Standardized photographs of the case before, immediately after and at 60 and 90 days is highly recommended, in order to, (1) obtain a record of the pre- and postprocedure changes of the face and neck region, (2) establish the presence or absence of any procedure related complications. Some representative preand post-Ultherapy procedure results at 90, 120, and 360 days are shown in Figures 9.7 and 9.8.

IFUS: Clinical Perspective on Fitzpatrick Skin Types III–VI   327

A

B

Figs 9.6A and B: Treatment guidelines (“Amplify”) for Ultherapy procedure. Up to 800 lines, with 12,000 TCPs are delivered using the 4.5 and 3.0 transducers at two planes of the skin tissue (4.5 mm and 3.0 mm) (With permission from Ulthera, Inc., USA)

Microfocused ultrasound is an energy-based system, and its prudent and controlled use is the key to minimize procedural complications and adverse events. Following established guidelines is important, especially avoiding regions of significant nerve distributions, described as “no-fly zones” in the guidelines (Figure 9.6). Known side-effects during procedure are pain, discomfort, and transient edema. Some linear cutaneous striations and rare dysthesia can occur post-procedurally, which resolves over 1–4 weeks. Detailed description of safety and side-effects are discussed in papers by MacGregor et al., Sasaki GH et al., and Dobke MK et al.

328  Lasers in Dermatological Practice

Fig. 9.7: Full-face and neck treatment with sustained improvement of eyebrow height, nasolabial folds, jawline and lifting of neck tissue over 360 days. (With permission from Ulthera, Inc., USA)

A

B

Figs 9.8A and B: Results at 120 Days post treatment, with substantial improvement in mid, lower face, jawline definition and neck laxity (A) Female; (B) Male (With permission from Ulthera, Inc., USA)

IFUS: Clinical Perspective on Fitzpatrick Skin Types III–VI   329

Recent guidelines and reports related to use of Ultherapy for full neck, décolletage, arms, abdomen and thigh region have been published. (Sasaki et al and Alster et al)

PATIENTS OF COLOR (FITZPATRICK SKIN TYPES III–VI) The ideal implementation and broad dissemination of energy-based systems for non-invasive surgical procedures should be predicated on a “colorblind” treatment approach. This goal is further relevant since more than 75 percent of the worlds population is of pigmented skin types III–VI (Halder RM). Despite these ethnic statistics, the safe use of energy-based systems in skin of color is not always possible, due to the biophysical limitations of particular energy modalities. For example, the use of photon-based devices (superficial depth and chromophore sensitive) is non-optimal for skin of color in aesthetic procedures, due to the possible adverse effects, such as hyper-pigmentation and other discromias, scarring and keloid formation. Compared to lighter Fitzpatrick skin types, the darker skin types are known to have unique characteristics, such as a thick compact dermis, abundance of melanin, preservation of skin elasticity (Halder RM, Rawlings AV, Davis EC). Not all energy modalities can fulfill the requirements to adequately and safely treat the darker skin types. The unique requirements for effective treatment are: (a) non-invasive “inside-out” approach, (b) chromophore insensitivity and, (c) ability to access multiple deeper layers (dermis and SMAS). Microfocused ultrasound systems are particularly suited to meet these requirements, since the energy for focal thermal coagulation bypasses the melanocytes, and is insensitive to other chromophores in the skin tissue. The energy is deposited depthselectable, and order of millimeters into the dermis and subcutaneous tissue. The use of Ultherapy in SE-Asia has been reported in the literature (Suh DH, Chan NP). One presentation describing the use of Ultherapy in patients of color has been made at a plastic surgery conference (Harris MO). However, no formal study of Asian-Indian skin type treatment with Ulthera has been reported to-date. A systematic case series was conducted in New Delhi, India to investigate the safety and efficacy of Ulthera procedures on face and upper neck treatment in Asian-Indian skin types (Nooreyezdan SS). The included cases in the study had the following characteristics: ¾¾ Females = 32; Males = 6 ¾¾ Age: 42–70 Years; Average = 49.8 Years ¾¾ Skin Types: Fitzpatrick Skin Types III–VI ¾¾ No history of cosmetic procedures 6 months prior to Ulthera procedure ¾¾ Willingness to not undergo and cosmetic procedures for at least 6 months post-Ultherapy

330  Lasers in Dermatological Practice

¾¾ Photographic and clinical assessment was performed immediately following Ultherapy ¾¾ Follow-up standardized photographs, frontal view (45° and 90°) taken at day 28, 60, 90 and 180. The study was conducted by four investigators; three plastic-reconstructive surgeons, and one dermatologist, based in India. After the initial training with Ulthera instrumentation, the investigators performed the procedures on their own recruited cases. All procedures were performed over 10 days at the same clinical location, using the same equipment. An identical protocol was followed by all clinicians. The steps for processing a case are as below: ¾¾ Provide two Combiflam (Ibuprofen 400 mg, paracetamol 325 mg), to patient, 60–90 minutes prior to Ulthera procedure—pain mitigation ¾¾ Consult patient and obtain patient’s consent ¾¾ Obtain standardized preprocedure photographs ¾¾ Mark face and neck region per treatment plan ¾¾ Deliver Ulthera procedure per Ulthera “Protocol 5-PLUS” (up to 500 Ultherapy treatment lines) ¾¾ Record patient pain scores (VAS 0–10), and other responses ¾¾ Conduct evaluation at half-procedure point ¾¾ Post-procedure assessment and standardized photography ¾¾ Day-60 follow-up standardized photography ¾¾ Day-90 follow-up photography ¾¾ Day 180 follow-up photography (subset of cases) The Ultherapy procedure was well-tolerated by all 38 cases, although pain score could not always be recorded. All cases could resume their daily activity following Ultherapy without any additional precautions or downtime. At day 60, 36 out of 38 cases returned for follow-up visit. For day 90 follow-up, 27 subjects returned for photography and assessment, while 14 subjects returned for a follow-up photography and assessment on day 180. In this, first reported comprehensive case-study for patients of Asian-Indian skin types, Ulthera procedure could be safely delivered to all the enrolled patients. The cases had no acute or long-term sequelae. Greater than 65% cases demonstrated a clinician evaluated mild to moderate improvement in the standardized photographic assessment. Selected photographs from the case study showing an increase in the eyebrow arch, mid-face tightening, improved jawline definition, improved submental tissue laxity, nasolabial fold improvement, and greater ovaling of the lower face are shown in Figures 9.9 to 9.12. Following this study, greater than 100 cases have since been clinically treated with favorable results and no adverse events by one of the investigators based in India.

CONCLUSION This chapter describes the role of intense focused ultrasound (IFUS) technology in non-invasive aesthetic applications for tissue laxity

IFUS: Clinical Perspective on Fitzpatrick Skin Types III–VI   331

A

B

Figs 9.9A and B: (A) Eyebrow elevation at 90 days; (B) Lower face ovaling, improved nasolabial folds at 60 days

Fig. 9.10: Tissue tightening mid-cheek, improved jawline, submental region and angle of neck at day 90

management and body contouring. The distinction of IFUS from ultrasoundassisted liposuction (UAL) has been made, as well as the basic biophysical principles which are characteristic of IFUS. The characteristics of various IFUS clinical systems such as Liposonix, Ultrashape, and Ulthera®, have been explained, as well as their therapeutic role in non-invasive cosmetic procedures. Differentiation between principal energy modalities has been

332  Lasers in Dermatological Practice

A

B

Figs 9.11A and B: Global tissue tightening—eyebrow height improvement, improved nasolabial folds, jawline definition, submental tightening and angle of neck at day 90

A

B

Figs 9.12A and B: (A) Improved jawline definition, tightening of submental area, no post-treatment sequelae in darker skin type; (B) Day 180 post-treatment: Consistent mid-face and submental tissue tightening

IFUS: Clinical Perspective on Fitzpatrick Skin Types III–VI   333

explained, as well as how their characteristics fit in attaining known tissue effects during clinical procedures. Details about the Ulthera technology and procedures have been expanded. Emphasis has been made in a first time reporting of a 38-patient case study describing the use of Ultherapy on Asian-Indian skin types. Photographic examples of pre-and post-results illustrate the outcomes from Ulthera procedures. Key issues with energy modalities for treatment of skin of color have been listed, in the context of the unique suitability of microfocused ultrasound (MFU-V) for treatment of dark skin types laxity and tissue tightening. The current published information for IFUS technologies has been listed in a comprehensive bibliography.

BIBLIOGRAPHY 1. Alam M, White LE, Martin N, et al. Ultrasound tightening of facial and 
neck skin: A rater-blinded prospective cohort study. J Am Acad Derma-Dermatol. 2010;62:262-9. 2. Alster TS, Tanzi EL. Noninvasive lifting of arm, thigh, and knee skin 
with transcutaneous intense focused ultrasound. Dermatol Surg. 2012;38:754-9. 3. Brown SA, Greenbaum L, Shtukmaster S, Zadok Y, Ben-Ezra S, Kushkuley L. Characterization of nonthermal focused ultrasound for noninvasive selective fat cell disruption (lysis): technical and preclinical assessment. Plast Reconstr Surg. 2009;124(1):92-101 4. Chan NP, Shek SY, Yu CS, Ho SG, Yeung CK, Chan HH. Safety study of transcutaneous focused ultrasound for non-invasive skin tightening in Asians. Lasers Surg Med. 2011;43:366-75. 5. Coleman KM, Coleman WP 3rd, Benchetrit A. Non-invasive, external ultrasonic lipolysis. Semin Cutan Med Surg. 2009;28(4):263-7. 6. Davis EC, Callender VD. Postinflammatory hyperpigmentation: a review of the epidemiology, clinical features, and treatment options in skin of color. J Clin Aesthet Dermatol. 2010;3(7):20-31. 7. Dobke MK, Hitchcock T, Misell L, Sasaki GH. Tissue restructuring by energybased surgical tools. Clin Plast Surg. 2012;39:399-408. 8. Doris D. Micro-Focused Ultrasound for Facial Rejuvenation: Current Perspectives. Research and Reports in Focused Ultrasound. 2014 (in print) 9. Fatemi A. High-Intensity Focused Ultrasound Effectively Reduces Adipose Tissue. Semin Cutan Med Surg. 2009;28:257-62. 10. Gadsden EI, Aguilar MT, Smoller BR, Jewell ML. Evaluation of a novel highintensity focused ultrasound device for ablating subcutaneous adipose tissue for noninvasive body contouring: safety studies in human volunteers. Aesthet Surg J. 2011;31(4):401-10. 11. Ghassemi A, Prescher A, Riediger D, Axer H. Anatomy of the SMAS revisited. Aesthetic Plastic Surgery. 2003;27:258-64. 12. Gliklich RE, White WM, Slayton MH, et al. Clinical pilot study of 
intense ultrasound therapy to deep dermal facial skin and subcutaneous tissues. Arch Facial Plast Surg. 2007;9:88-95.

334  Lasers in Dermatological Practice 13. Halder RM, Ed. Dermatology and Therapy of pigmented skins. Taylor and Francis, Boca Raton, 2006 14. Harris MO. Evaluation of Micro-Focused Ultrasound for Obtaining Lift and Tightening of the Cheek Tissue and Improvement in Jawline Definition and Submental Skin Laxity in Patients with Fitzpatrick Skin Phototypes 3 through 6. AAFPRS Washington DC, Sept. 2012 15. Har-Shai Y, Bodner SR, Egozy-Golan D, et al. Mechanical properties and microstructure of the superficial musculoaponeurotic system. Plast Reconstr Surg. 1996;98:59-70. 16. Jewell ML, Baxter RA, Cox SE, Donofrio LM, Dover JS, Glogau RG, et al. Randomized sham-controlled trial to evaluate the safety and effectiveness of a high-intensity focused ultrasound device for noninvasive body sculpting. Plast Reconstr Surg. 2011;128(1):253-62. 17. Jewell ML, Desilets C, Smoller BR. Evaluation of a Novel High-Intensity Focused Ultrasound Device : Preclinical Studies in a Porcine Model. Aesthetic Surgery Journal. 2011;31:429 18. Jewell ML, Solish NJ, Desilets CS. Noninvasive body sculpting technologies with an emphasis on high-intensity focused ultrasound. Aesthetic Plast Surg. 2011;35(5):901-12. 19. Kennedy JE, ter Haar GR, Cranston D. High intensity focused ultra- sound: Surgery of the future? Br J Radiol. 2003;76:590-9. 20. Laubach HJ, Makin IR, Barthe PG, et al. Intense focused ultrasound: Evaluation of a new treatment modality for precise microcoagulation within the skin. Dermatol Surg. 2008;34:727-34. 21. MacGregor JL, Tanzi EL. Microfocused ultrasound for skin tightening. Semin Cutan Med Surg. 2013;32:18-25. 22. Miller DL, Smith NB,, Bailey MR, Czarnota GL, Hynynen K, Makin IRS,. Overview of Therapeutic Ultrasound Applications and Safety Considerations. Ultrasound Med. 2012;31:623-34. 23. Nooreyezdan SS. Face and Neck Tissue Lifting and Tightening with MicroFocused Ultrasound in Fitzpatrick Skin Types II – VI. ISAPS, Goa, Jan. 2012 24. Rawlings AV. Ethnic skin types: are there differences in skin structure and function? International Journal of Cosmetic Science, 2006;28:79-93. 25. Rohrich RJ, Morales DE, Krueger JE, Ansari M, Ochoa O, Jack Robinson, et. al. Comparative Lipoplasty Analysis of in Vivo-Treated Adipose Tissue. Plastic and reconstructive surgery. 2000;105(6):2152. 26. Sasaki GH, Tevez A. Clinical efficacy and safety of focused-image ultrasonography: A 2-year experience. Aesthet Surg J. 2012;32:601-12. 27. Sasaki GH, Tevez A. Microfocused Ultrasound for Nonablative Skin and Subdermal Tightening to the Periorbitum and Body Sites: Preliminary Report on Eighty-Two Patients. Journal of Cosmetics, Dermatological Sciences and Applications. 2012;2:108-16. 28. Suh DH, Shin MK, Lee SJ, et al. Intense focused ultrasound tightening in Asian skin: Clinical and pathologic results. Dermatol Surg. 2011;37:1595-1602. 29. Teitelbaum SAI, Burns JL, Kubota J, Matsuda H, Otto MJ, Shirakabe Y, et al. Noninvasive body contouring by focused ultrasound: safety and efficacy of the

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30. 31. 32. 33.

34.

Contour I device in a multicenter, controlled, clinical study. Plast Reconstr Surg. 2007;120(3):779-89 ter Haar G. Acoustic Surgery, Physics Today 29-34,2001 ter Haar GT, Coussios C. High intensity focused ultrasound: physical principles and devices. Int J Hyperthermia. 2007;23:89-104. Ulthera Update White Paper. Comfort Management. 2012 White WM, Makin IR, Barthe PG, et al. Selective creation of thermal injury zones in the superficial musculoaponeurotic system using intense ultrasound therapy: A new target for noninvasive facial rejuvena- tion. Arch Facial Plast Surg. 2007;9:22-9. White WM, Makin IR, Slayton MH, et al. Selective transcutaneous delivery of energy to porcine soft tissues using intense ultrasound (IUS). Lasers Surg Med. 2008;40:67-75.

Chapter

10

Noninvasive Body Contouring Vivek Nair, Kabir Sardana

Introduction Noninvasive body contouring is an ever-expanding field that has seen exciting research and development over the last decade. Beginning with suction-massage machines over 20 years ago, the technology has progressed to involve sophisticated laser and radiofrequency devices. The commonly practiced laser lipolysis, is one component of the array of devices. As per the revised nomenclature (Alam et al. 2013) the devices for Body Contouring can be divided into three categories (Box 10.1). This classification may seem daunting for someone getting into body shaping platforms. However, the picture becomes clearer if the machines are classified according to the energy used for transepidermal delivery to Box 10.1 Body contouring devices (as per revised nomenclature by Alam et al. 2013) A. Nonsurgical body contouring and fat reduction 1. Ultrasound a. High intensity (e.g. Liposonix, Ultrashape) b. Low intensity c. Focused d. Nonfocused (e.g. Bella contour) 2. Cryolipolysis (e.g. Zeltiq) 3. Low-intensity light therapy light (LLLT) (e.g. Zerona) 4. Massage 5. Electric field (e.g. Bella contour) B. Energy-device-assisted liposuction 1. Laser lipolysis with liposuction (e.g. CoolLipo, ProLipo, SmartLipo, LipoLite) 2. Ultrasound-assisted liposuction 3. Water-assisted liposuction (e.g. Body-Jet) 4. Power-assisted liposuction (e.g. MicroAire) categories of: microwave thermolysis 1. Noninvasive 2. Invasive

Contd...

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Contd... C. Radiofrequency and ultrasound skin tightening 1. Noninvasive radiofrequency a. Monopolar radiofrequency (e.g. Thermage, Exilis) b. Unipolar radiofrequency c. Bipolar radiofrequency (e.g. Alma Accent, Syneron eMax) d. Tripolar radiofrequency (e.g. Pollogen RegenXL) e. Multipolar radiofrequency. 2. Minimally invasive radiofrequency Needle insertion array 3. Fractional radiofrequency (by any radiofrequency delivery method listed above) 4. Focused, high-intensity ultrasound (synonym: ultrasound skin tightening) (e.g. Ulthera Ultherapy).

the adipocyte; in which case there are four primary modalities—suction/ massage machines, radiofrequency machines, ultrasound machines, and laser machines. The areas of fat deposition are essentially localized to certain areas (e.g. love handles, lower abdomen bulges, thighs). Tumescent liposuction using suction cannulas is a time-tested technique with about 300,000–400,000 procedures performed in the US annually. Though overall a safe procedure complications like prolonged swelling, areas of numbness, bruising, persistent erythema, thrombophlebitis, and pulmonary embolism can occur. Given the fact that many patients do not want to undergo surgery of any kind to remove excess fat, the market for the noninvasive devices is expected to grow at an exponential rate. In 2009, the projected figure for the body shaping platform market was over $300 billion with over 9 million procedures performed world wide. USA, Europe, and Southeast Asia have seen the maximum number of these procedures, but the market in India is expected to follow a similar trend. Excess fat and obesity are an epidemic wherein excess, but structurally normal, adipose tissue is deposited. Cellulite, on the other hand, is best considered a hormonally based structural phenomenon of adipose tissue. It is seen almost ubiquitously in post-pubescent females and, rarely, in men. As a result of these differences, the techniques and technology that effectively treat excess fat may not have any effect on the appearance of cellulite, and vice versa. This chapter mainly deal with the noninvasive body contouring technologies as well as a brief discussion on the minimally invasive lipo­ suction techniques that have become possible, because of the use of lasers and adjunctive technologies like radiofrequency and ultrasound.

Cellulite This condition is characterized by a “orange-peel “ appearance and is localized to certain areas . Obesity, on the other hand is characterized by an

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universal increase in size and number of adipose cells. Fat is a healthy tissue, found in the human body that develops in terms of number of cells from birth until full sexual maturity. Throughout the rest of our lives, the number does not change, but the volume does. Adipose tissue in men is different from the one in women: ¾¾ numerically, men have 17–18 million cells and women 21–22 million ¾¾ structurally, the connective tissue that surrounds the adipose cells in men forms a mesh structure; in women, it is connected by fibers positioned perpendicular to the tissue levels (Fig. 10.1). Structurally, the subcutaneous compartment is different in patients with and without cellulite. Based on analysis of adipose tissue, Nurnberger and Muller reported indentations into the deep adipose tissue through the dermis and perpendicular fibrous septae in women. In contrast, the fibrous septae run in a crisscross pattern in men. Thus, the horizontal, crisscross pattern of connective tissue at the dermal–subcutaneous junction and thicker dermis prevents bulging or dimpling of fat in men (Fig. 10.1). Subcutaneous adipose tissue is thicker with larger adipocyte lobules in skin with cellulite compared with unaffected skin. The factors that trigger the degenerative process of cellulite are lifestyle, hormones, stress, clothing, genetic predisposition, physical disorders, metabolic disorders, smoking, increased mass, age, medicines (contraceptive pill, antidepressants), lack of physical exercise, etc. The effect of these includes the following: 1. Reduction in the venous and lymphatic microcirculation. 2. Increase in fat deposits,which in conjunction with reduced catabolism, leads to thickening and hardening of the connective tissue. 3. Increased mass leads to increase in fat deposits with a reduction in venous and lymphatic microcirculation. This in conjunction with reduced catabolism and thickening and hardening of connective tissue causes cellulite. It must be remembered that there is little correlation between excess adipose tissue and cellulite. There are many thin females who have the appearance of cellulite on their bodies, whereas some heavier females may display only a subtle appearance of any cellulite (Fig. 10.2).

Fig. 10.1: A comparison between the orientation of connective tissue between men and women accounting for cellulite

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Fig. 10.2: Comparison of normal and cellulite tissue

Assessment Tools Cellulite can be assessed by direct observation with side lighting. Based upon these observations, a relatively simple scoring system for the appearance of cellulite has been described, (Table 10.1) though very little data exist on grade-specific therapeutic measures.

Treatment of Cellulite There are two main goals for treating cellulite: 1. Tighten and strengthen lax connective tissue and bolster underlying subcutaneous fat. 2. Target and reduce the actual subcutaneous fat that contributes to the “lumpy” surface appearance of cellulitic skin. Nonablative modalities that selectively focus thermal injury into the dermis while sparing the epidermis, such as radiofrequency devices, are used commonly to tighten facial skin and may also produce similar effects in patients with cellulite. Targeted reduction of subcutaneous fat with nonablative laser devices and focused ultrasound is also being tried. Anderson et al. recently showed that the 1,210 and 1,720 nm wavelengths, wherein the absorption coefficient of human fat is greater than that of water, may allow selective heating of adipose tissue with minimal damage to surrounding structures. There are no commercially available devices utilizing these wavelengths. The treatment armamentarium targeted toward cellulite includes weight loss, topical pharmacologic agents, and physical mechanisms. The main pharmacologic treatment options include methylxanthines (caffeine, aminophylline, and theophylline) and retinol. Interestingly weight loss itself does not help in treating cellulite (Table 10.2).

340  Lasers in Dermatological Practice Table 10.1 Grading of cellulite Phase 0

Phase 1

Phase 2

Phase 3

Even skin when standing

Even skin when standing and lying

Even skin when lying down

Always dimpled skin

Pinch test only few dimples

Pinch test shows dimpled skin

Dimple skin when standing

Table 10.2 Overview of therapeutic modalities for cellulite/obesity Device based

Others

Radiofrequency devices (Celluite) 1. VelaSmooth:*† bipolar RF, infrared heat, and suction device 2. Alma Accent RF System (Alma LasersTM, Israel)†Unipolar and bipolar radiofrequency 3. ThermaCool (Thermage, USA) : unipolar radiofrequency Both of these devices are FDA approved for rhytides. Only the Alma System and the VelaSmooth have been studied in peer reviewed journals.

Botanicals Garcinia cambogia Caffeine Piper nigrum Ginkgo biloba Centella asiatica Papaya Green tea

Endermologie (Cellulite) Light sources and massage (Cellulite) 1. TriActiveTM (CynosureTM, USA)* : 810 nm diode laser with vacuum massage 2. Synergie esthetic Massage SystemTM (Dynatronics, USA):* Vacuum massage with or without a 660–880 nm probe or 880 nm light pad 3. SmoothShapes (Elemé Medical, USA)*  915 nm laser and 650 nm light source combined with vacuum and mechanical massage.

Weight loss ?

Laser-assisted liposuction (Adipose tissue)

LED plus topical phosphatidylcholine-based gel

Ultrasound(Adipose Tissue)

Mesotherapy

Intense Pulsed Light(Cellulite)

Liposuction Subcision

*FDA Approved for cellulite ,†Published studies

Though most of the procedures listed (table 10.2) can be used for cellulite, as the pathogenesis has multiple factors including fibrosis, circulatory failure, and an underlying metabolic failure, no single therapy is effective. Of the available devices on the market, those with radiofrequency seem to have the most effect. These devices do not yield more than a 50% improvement in most subjects. Most do not employ clearly objective means of proving clinical efficacy, casting doubt on the true efficacy of these devices.

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Laser Lipolysis To understand how noninvasive body shaping works, it is important to understand how fat is metabolized and stored in the human body. Whenever the caloric intake exceeds demand, the excess energy is stored in the form of triglycerides in the specialized cells called adipocytes. Such cells are present in various body areas, but for the purpose of noninvasive body shaping, we will concentrate our attention on the adipocytes in the skin which make up the subcutaneous fat layer. The adipocyte is a cell with a large amount of cytoplasm capable of storing a large amount of triglycerides. These form the energy reserve of the body. The number of adipocytes is regarded to be fixed, but their size can show great variability. When enlarged, they disrupt the natural body contours resulting in local fat collection and, in extreme cases, obesity. So, how does one go about decreasing fat in the subcutaneous layer? There are only two ways—either decrease the cell number or decrease their size. The former is accomplished by methods which either mechanically remove fat cells, such as liposuction or by methods which cause adipocyte death through one mechanism or the other. The latter involves getting the adipocyte to give up its triglyceride content through membrane manipulation. The released TAG is transported from the interstitial space to the lymphatic channels from where it is metabolized by the liver. Numerous studies have shown the safety of these techniques, and there have been no reports of fatty liver/ liver dysfunction or increased serum triglycerides following noninvasive fat reduction techniques. The first mechanism, adipocyte removal or death, offers longer-lasting results than adipocyte fat removal, since as mentioned earlier the number of adipocytes is fixed throughout life. However, since the remaining adipocytes can increase greatly in size to compensate for the numbers lost, it is essential that lifestyle modifications (i.e. diet, exercise) are done on a sustained basis by the patient to maintain desired results. This is even more important with the more temporary method of fat removal from a viable adipocyte. There are three mechanisms of removal of fat (TAG) from the adipocytes: 1. Thermal augmentation of normal metabolic processes of the fat cell. 2. Thermal or cavitational destruction of fat cells. 3. Creation of a temporary pore in the fat cell membrane. A significant barrier to noninvasive treatments is the issue of fat localization after treatment. Adipose tissue stores triglycerides. Unlike cholesterol, which can be excreted, triglycerides are not excreted by the body; in fact, they are stored and used for such molecules as plasma lipoproteins. Thus, the removal of large deposits of subcutaneous fat may yield redistribution to other sites in the body. Since increased visceral fat has been linked to increased cardiovascular disease, noninvasive therapies should be approached cautiously, and their use may be limited to treatment of small deposits of fat.

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Assessment Tools Body mass index (BMI = person’s weight in kilograms divided by the square of their height in meters) remains the classic method for determining obesity. But this has issues as many patients presenting for noninvasive body sculpting may be in very good shape overall with only a few small problem areas such as the thighs or flanks. Thus, for laser procedures, thigh circumference, waist circumference, skinfold thickness, visual assessment, and photographic comparisons, preand post-procedure are more useful

Indications and Contraindications of Non Invasive Body Contouring Indications ¾¾ Realistic expectations of a modest reduction of localized fat—generally, only soft tissue deformities with at least 1.5 cm of fat thickness should be treated ¾¾ Patient opposed to a surgical procedure for fat reduction ¾¾ Compliance with multiple visits for procedures.

Contraindications ¾¾ ¾¾ ¾¾ ¾¾ ¾¾

Pregnancy Patients with a pacemaker Patient with a serious or debilitating medical illness Patients with a large BMI Unrealistic expectations.

Treatment Devices Though we are listing the devices below it must be understood, just what one intends to treat. Table 10.2 gives an overview of the devices being used and identifies the device that can be used for a particular indication, i.e cellulitis of obesity.

Suction/Massage Devices These are amongst the oldest machines available for noninvasive fat loss. Endermologie is a technology that originated two decades ago in France that uses paddles coupling suction and a roller to stimulate fatty areas. The concept is that lymphatic circulation in the treated area is stimulated resulting in mild fat loss from adipocytes. In selected patients, particularly those with edematous type of fatty deposits, the procedure can result in measurable circumference reduction. For most people, the improvement is very mild and the machine is mostly used in the day spa environment.

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Endermologie® (LPG Systems, Valence, France) is an FDA-cleared device that massages and kneads the skin to improve the appearance of cellulite. This is supposed to work by stimulating blood and lymphatic flow, thereby, altering the architecture of the fat and improving the appearance of cellulite. The results though are modest both in the appearance of fat and cellulite. Newer machines take the above concept further by coupling the suction with transepidermal thermal energy delivery (Table 10.2). This thermal energy is generated with the help of diode arrays or nonfocussed ultrasound around the probe head. TriActiveTM (Cynosure, Inc.,Westford,MA,USA) and SmoothShapes (Cynosure, Inc., Westford, MA, USA) are two such devices. Again results are modest and these machines are often used in as adjuncts to other fat removal methods (e.g for smoothening out results and tightening skin after surgical liposuction).

Radiofrequency Energy Devices These are the most popular noninvasive fat loss devices in the world. Radiofrequency devices can be classified into multiple types (Box 10.2), but unipolar, bipolar or multipolar devices are commonly used.

How do they Work? Bipolar RF devices are based on the principle of heat generation as a result of poor electrical conductance, as the RF waves pass through fat. the resulting heat is strong enough to cause thermal damage to the adipocytes and connective tissue septae. Adipose tissue has high tissue resistance and Box 10.2

Body contouring devices*

1. Suction: Massage devices a. Endermologie 2. Suction-massage: Thermal devices a. TriActiveTM (Cynosure, Inc.,Westford,MA,USA) b. SmoothShapesTM (Cynosure, Inc., Westford, MA, USA) 3. Radiofrequency energy devices a. VelaSmooth, VelaShape (Syneron, Inc., Irvine, CA, USA) b. Thermage (Solta Medical, Hayward, CA, USA) c. AccentTM (Alma Lasers Inc, Buffalo Grove, IL, USA) d. TiteFXTM (Invasix, Inc., Yokneam, Israel) 4. High-frequency focused ultrasound energy devices a. UltraShapeTM (UltraShapeLtd.,Yoqneam, Israel) b. LipoSonixTM (Medicis, Scottsdale, AZ, USA) 5. Cryolipolysis energy devices a. ZeltiqTM (zeltiqaesthetics, pleasanton, CA, USA) 6. Low-level light laser therapy devices a. ZeronaTM (Erchonia Medical, McKinney, TX, USA) 7. Microwave by thermolysis *As proposed by Mulboland et al.

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a relatively low heat transfer coefficient; thus, adipose tissue can be readily heated, and the heat will be predominantly confined to the adipocytes. Bipolar RF devices have a penetration depth of >3 mm and allow for better control and localized adipose tissue alteration. Unipolar devices utilize high frequency electromagnetic radiation (EMR). High frequency EMR induces high frequency rotational oscillations in water molecules, which in turn produce heat, i.e. greater the presence of water, greater is the tissue heat generation. The depth and breadth of thermal damage is greater and in a rather diffuse pattern with little control as compared to bipolar RF devices. The end result is the creation of dermal fibrosis through neocollagenesis or so-called “appearance-enhancing scarring” that leads to long-term improvement after fewer treatments. The heat generated increases adipocyte fat turnover but does not kill the adipocyte. Unipolar and bipolar RF technologies also exist as combination Accent/ Alma device (Alma lasersTM, Buffalo Groove, IL). The Alma Accent RF system (Alma lasers, Buffalo Groove, IL) and ThermaCool (Thermage, Hayward, CA) utilize RF and may be useful in the treatment of cellulite. Both the Accent and ThermaCool are FDA approved for the treatment of wrinkles and rhytides. The ThermaCool is a unipolar RF, while the Accent system is a unipolar and bipolar RF device. Of the two devices, only Accent system has been evaluated for the treatment of localized adiposities (Table 10.2).

VelaSmooth and VelaShape VelaSmooth was the first RF based device approved for cellulite reduction by the FDA in 2005. This was followed two years later by the higher powered VelaShape which has since then undergone three revisions. VelaShape is FDA approved for both cellulite and circumference reduction. This machine uses a combination of radiofrequency energy as well as infrared light wavelengths to treat cellulite noninvasively. The infrared light spectrum ranges from 680 to 1500 nm and can possibly penetrate up to 5 mm below the skin. Both VelaSmooth and VelaShape systems combine Infrared light (700 nm to 2000 nm) with suction coupled Bipolar RF (1 MHz) and mechanical manipulation, the difference being that VelaSmooth is rated at 25 W while VelaShape is rated at 50 W and is thus more powerful. During treatment suction is used to pull the skin into the handpiece where the skin is exposed to IR and RF while its surface temperature is being monitored. IR mainly targets dermal water while RF targets the deeper dermis and subcutaneous fat layer. The resulting heat stress causes dermal contraction and stimulates increased vascular flow and neocollagenesis and in the subcutaneous layer increases the metabolism of the adipocyte resulting in TAG removal from the cell. The suction and mechanical massage from the probe stimulate lymphatic flow further enhancing fat removal.

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Results: In the largest study of VelaSmooth, Sadick evaluated 35 patients who completed either 8 or 16 treatments with VelaSmooth. A blinded dermatologist evaluated the photographs and found 40% improvement on average in cellulite appearance, and there was a circumference reduction in all. Numerous studies have repeatedly shown the efficacy of VelaSmooth in improving cellulite, but a few studies have shown circumference reduction as well ranging from 1.25 to 3.5 cm on the abdomen and thighs and 0.5–0.75 cm on the arms. A more recent study of VelaSmooth found a statistically significant decrease in thigh circumference at 4 weeks, but no immediate change or a persistent decrease at 8 weeks. Visual improvement of less than 50% was noted in the majority of subjects and 31% of the subjects experienced bruising. Hence, it seems that cellulite reduction remains the main application of the machine. Sessions vary from weekly to biweekly and number of session, from four to sixteen. Benefit is seen as early as one month, and in one Asian study was sustained over one year.

Unipolar RF Devices Thermage and Accent are two prominent unipolar (monopolar) RF devices employing pure RF without adjunctive IR or suction coupling. The limitation of RF is that the energy is not specific, unlike ultrasound waves, and their depth of penetration into the skin is limited unless very high levels are used. Hence, both treatments are more suited to nonsurgical skin tightening than fat reduction. Cellulite is superficial fat as compared to the subcutaneous fat layer, and hence, this may improve as well. Both machines can be associated with significant discomfort during the procedure. Results: Studies have assessed Thermage in the treatment of cellulite with improvement scores ranging from 30 to 70%, 6 months post-treatment. Accent is similar to Thermage and uses high frequency RF for skin tightening, cellulite reduction and modest circumference reduction. Goldberg et al. studied the use of the Accent unipolar RF device for cellulite treatment. Their study included subjects with higher grade cellulite of upper thighs. They were treated every other week for a total of six treatments. Results obtained 6 months after the last treatment showed an average 2.45 cm reduction in thigh circumference with minimal side effects, and no changes in serum-lipid abnormalities, and MRI were seen. They attribute their longerlasting effects to the formation of dermal fibrosis in the upper dermis and increased contraction between the dermis and camper’s fascia, which has been previously reported in ultrasound imaging studies. The presence of thickened dermal fibrous band or so called “scarring” is concerning regarding long-term effects. It is known that postmenopausal women tend to lose more weight in the femoral area as compared to premenopausal women, who tend to gain more.

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For women who would undergo unipolar RF treatment in their reproductive years might lose weight later on. Since scarring induced by unipolar RF devices is permanent, long-term improvement is questionable and concerning.

Tripolar Radiofrequency TriPollarTM (Pollogen, Tel Aviv, Israel) and FreezeTM (Venus Concepts) are some other RF machines. TiteFxTM is a variation on the RF concept and uses suction coupled RF to heat the dermis and first 1.5–2 cm of fat. When the epidermal temperature reaches 43 to 45° C, a high-voltage, electroporation pulse is generated through the adipose tissue resulting in damage to the adipocyte membrane and resultant apoptocysis over the following week. The device is much quicker than Thermage making the treatments more tolerable.

Conclusion Though most of these devices have been used for skin tightening some have a potential for use in cellulite. There are issues with most of these devices , notably the lack of adequate histological confirmation in most and of course lack of sustained results !

High Intensity Focused Ultrasound (HIFU) Ultrasound devices for fat reduction can be divided into those using nonfocused versus focused high frequency ultrasound. Nonfocused ultrasound (NFU) devices just have a dermal heating effect with minimal or no fat reduction; hence, our discussion with focus on HIFU.

How does it work ? In a conducive setting, ultrasonic energy affects tissue destruction through three mechanisms: cavitation, micromechanical disruption, and thermal damage. It is thought that cavitation is predominantly responsible for tissue destruction in internal ultrasound assisted liposculpting (UAL). NFU devices lack the ability to cause cavitation and, hence, are not effective for fat loss. It is postulated that external ultrasound prior to liposuction works either through thermal or micromechanical effects. A nonablative thermal treatment would not be expected to have a significant or durable effect on fat. In fact, external nonfocused therapeutic ultrasound has been applied to body contouring but was found to be effective only as an adjunct to tumescent liposuction, improving tissue hydration and distribution of the tumescent solution.

Ultrashape Transdermally focused Contour I UltraShapeTM (Tel Aviv, Israel) uses focused ultrasound to deliver a finite amount of acoustic energy at a controlled

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distance from the ultrasound transducer to achieve noninvasive body contouring. Ultrasound energy is emitted from a hemispherical transducer (fig. 10.3). The energy is low near the transducer surface and is concentrated in an additive manner at a distant focus. The transducer is placed directly on the skin and focuses the energy at the depth of the subcutaneous fat. As a result, the energy can be delivered through the skin, with low energy density at the epidermis and dermis, and with a high energy density in the subcutaneous fat. The ultrasound energy is delivered in pulses, using parameters that provide a nonthermal effect. High levels of ultrasound energy within the subcutaneous fat can disrupt adipose tissue safely and effectively, as has been demonstrated in ultrasound-assisted liposuction. Tissue selection is achieved partly due to the pulsed nature of the pulses and party due the differential susceptibility of different tissues to mechanical (non-thermal) stress. Results: A prospective, non-randomized, controlled trial (n = 164 patients) conducted by Teitelbaum et al. found that after one ultrasound treatment to the abdomen, thighs, or flanks there was a after 12 weeks a mean circumference reductions of 2.3 cm (abdomen), 1.8 cm (thighs), and 1.6 cm (flanks). The majority (77%) of the improvement in circumference was noted to occur within the first 14 days following the treatment. Interestingly, one Asian study failed to demonstrate much improv­ ement—53 patients were treated with 3 sessions spaced a month apart and there was no significant difference in the pre- and post-treatment parameters, such as circumference reduction, ultrasound fat thickness and skin caliper fat thickness. This has been hypothesized to be because

Fig. 10.3: A figurative depiction of focused USG used for fat reduction

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of body habitus difference between Asians and Caucasians. Since then the UltraShape has undergone two revisions—the so called second and third generation UltraShape—with software upgrades and better transducers. The third generation UltraShape also has 2 additional technologies built into it— advanced nonthermal selective focused ultrasound and vacuum-assisted RF combined. These 2 technologies allow same-session combination therapy, facilitating a synergistic treatment protocol, thus, producing a complete body-contouring solution. Over 200,000 UltraShape treatments have been performed worldwide with no reports of any significant adverse event. The procedure is comfortable and patients start seeing a difference within a month. In general, an average of 2–4 cm of circumferential fat reduction can be achieved over 3 sessions spaced 2 weeks apart from the abdominal and hip regions, and about 2–3 cm from the inner and outer thighs. With the third generation machine, it is anticipated that this can occur after a single treatment.

LipoSonixTM LiposonixTM is the other main HIFU system; however, it differs significantly from UltraShape in several parameters. Liposonix uses two HIFU rays to focus on a very localized area causing rapid heating (> 56° C) of the tissue, with a variable focal depth of 1.1–1.8 cm. This causes coagulative necrosis of the fat cell and instantaneous cell death. So, the effect is thermal as opposed to the non-thermal effect of UltraShape. This also makes the procedure quite painful and sedation is required in contrast to UltraShape, which requires none. Distilled water needs to be used as a coupling agent to prevent acoustic reflection of the high frequency ultrasound waves from air pockets in between the transducer–skin interface. Adverse events seen include swelling, ecchymoses, dysesthesia, and pain on treatment, unlike UltraShape which has virtually no side effects. Fewer sessions are required with the Liposonix though with studies showing 2–5 cm circumferential reductions after a single sitting. Results: Studies have shown significant improvement following a single treatment session. But a high intensity dose setting is helpful and is associated with more pain, bruising, and edema.

Summary Although Contour I UltraShapeTM is widely used for noninvasive body contouring, data regarding the long-term efficacy and persistence of satisfactory results is still lacking. Whether the treated patients will require regular treatments for maintenance of achieved results indefinitely, is still unanswered.

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Lightbased Devices and Laser-assisted Lipolysis (LAL) Laser lipoplasty with pulsed neodymium, yttrium, aluminum, garnet (Nd:YAG) laser, also called interstitial laser lipolysis was first described in 1994. This technique is widely used in Europe and Latin America and has recently been introduced in Japan and the United States. Less trauma, bleeding, and pain have been the main advantages of this technique (Table 10.2).

How Does it Work ? The mechanisms leading to laser lipolysis is largely temperature dependent. At low-energy settings, tumescent adipocytes were observed. At higher energy settings, cytoplasmic retraction, disruption of membranes, and heatcoagulated collagen fibers are seen. The various devices used have to be understood in respect to the absorption spectrum as given in the Table 10.3 that shows an ideal wavelength seems to be 1440 nm. Wavelengths, such as 1210 nm and 1720 nm are highly specific for lipids, but there are no devices at present with these wavelengths.

Devices Used Pure Laser Devices 1. The Nd:YAG laser was first used in laser lipolysis, because of the penetration depth of its wavelength (1,064 nm). The Nd:YAG laser has been used alone or in combination with suction liposuction. SmartLipoTM (Cynosure, USA), a 300 µm fiber encased in a micro-cannula, is an example of this type of device. The cannula is inserted subcutaneously to destroy lipid membranes and release lipids. Adipocytes appear to swell at lower energies and lyse at higher energies. The laser heat also coagulates collagen fibers. This process is termed as “laser lipolysis” (Ichikawa K). Strictly speaking, “lipolysis” is defined not as destruction of the adipocyte membrane, but rather as shrinkage of the fat cell due to the use of lipid for energy at the cellular level. 2. Diode lasers, which can typically emit at 810, 940, and 980 nm, is another alternative. Their wavelengths are in the same spectral region as 1064 nm, Table 10.3 Absorption spectrum of various wavelengths Wavelength

Fatty Tissue/Water Absorption

924 nm (Diode)

2.8/1.4

980 nm (Diode)

1.7/3.6

1064 nm (Nd:YAG)

1/1

1320 nm(Nd:YAG)

5.9/11.5

1440 nm(Nd:YAG)

127/252

350  Lasers in Dermatological Practice

and they offer the advantages of higher efficiency (usually 30%) and higher power (25 W or more). The absorption spectrum of mammalian fat obtained by VanVeen et al. using three independent methods show that the absorption coefficient obtained with a wavelength of 980 nm is very similar to that obtained with a wavelength of 1,064 nm. 3. 1440 nm lasers: Based on the absorption spectrum as given in table 10.3 the ideal wavelength for fat absorption is 1440 nm. The 1440 nm wavelength is highly absorbed in adipose tissue, which is composed of 75% fat, 20% water, and 5% proteins. This is as the 1440 nm wavelength is absorbed by adipose tissue 127 times greater and absorbed by water 252 times greater than the 1064 nm wavelength. Cellulaze (Cynosure) is a laser device that uses a 1440-nm Nd:YAG fiber with a novel delivery system to target the structural components of cellulite. The technology incorporates a unique SideLight SideFiring Fiber as well as a ThermaGuide thermal sensing system for safer treatments. 4. 635 nm laser and liposuction: Neira has combined low level 635 nm laser and liposuction in a technique labeled the “Neira 4 L technique”. Patients are irradiated with a low-level 635 nm laser after tumescent anesthesia. Following irradiation, removal of fat is accomplished with a cannula or other technique. Neira postulated that low level laser creates a pore in the adipocyte membrane, causing leakage of lipid into the interstitial space. He studied 12 patients and found that after 6 min of low level laser, fat was completely removed from the cell.

Combined Devices 1. The SmoothShapes (Eleme Medical, Merrimack,NH, USA) device for the treatment of cellulite is a dual wavelength, 915 nm and 650 nm, laser device that is combined with a vacuum-assisted mechanical massage. The basis of these wavelength selections is based on adipose samples treated with a 635 nm light from a 10 mW diode laser, which showed emptying of fat from these cells (Neira R ). Then the 915 nm wavelength penetrates into the tissue and is preferentially absorbed by lipids, causing a thermal effect. The temperature inside the adipocyte is elevated by up to 6° C. The 650 nm wavelength is thought to modify the permeability of the fat cell membranes, allowing expressed fat to move into the interstitial space, without ever destroying the adipocyte cell membrane. The fat is moved into the interstitial space and lymphatic system for elimination with the aid of mechanical rollers and mild suction. Without the use of rollers and suction, the fat would return into the adipocyte within 45 minutes.

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2. The TriActive® device (Cynosure Inc., Bedford, MA) combines deep tissue massage and suction (similar to Endermologie®), with contact cooling and a low-intensity diode laser (808 nm). The TriActive (Cynosure, Westford, MA, USA) platform used 3 components to treat cellulite specifically: contact cooling, massage, and a diode laser. It has been shown that the diode laser component significantly contributed to clinical improvement. Work done by Nootheti PK et al. compared the efficacy of treatment of cellulite using TriActive vs. VelaSmooth. Patients were treated twice weekly for 6 weeks with either VelaSmooth or TriActive. They calculated a 28 vs. a 30% improvement rate, respectively, in the upper thigh circumference measurements, while a 56 vs. a 37% improvement rate was observed, respectively, in lower thigh circumference measurements. Statistical significance of these results was p > 0.05. Incidence and extent of bruising was higher in VelaSmooth than in TriActive system, which may be attributed to mechanical manipulation. 3. The VelaSmooth and VelaShape (Syneron Medical Ltd, Irvine, CA) devices, as discussed previously, combine physical manipulation with radiofrequency energy, as well as infrared energy, to facilitate a multimodality approach to fat and cellulite treatment.

Procedure Patient Selection: This is a crucial part of delivering results with LAL. The ideal patient should be thin with localized pockets of fat that need treatment. The patient should be in good health. The need for maintaining a healthy lifestyle (diet, exercise) after the procedure should be emphasized, and there should preferably not be a history of frequent or rapid weight gain and weight loss in the past. The patient should have realistic expectations from the procedure, and it must be clearly explained before hand that LAL is not a method of weight loss but of body contouring. Any areas with unwanted adiposity can be treated with LAL. Commonly treated areas are the abdomen, flanks, submental region, upper arms, buttocks and thighs. Other areas like the knees, calves, ankle, breast, lipomas and localized adiposities left from previous liposuctions can also be treated.

Contraindications Absolute ¾¾ Pregnancy ¾¾ Bleeding diathesis ¾¾ Lignocaine allergy ¾¾ Serious debilitating illness of any kind.

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Relative ¾¾ Compromised liver function ¾¾ Age over 65 ¾¾ Hypertension ¾¾ Diabetes ¾¾ Cardiovascular problems.

Preoperative Workup Standard preoperative investigations that must be done in every patient include CBC, liver function tests, blood sugar, kidney function tests, lipid profile, HIV, HBsAg, anti-HCV, bleeding parameters, and in the case of women, a urinary pregnancy test, if applicable. Surgeons differ in their use of preoperative medications, and the experts do not recommend any routine medications.

Techniques 1. The part to be treated is clearly marked out in a standing position. This is important because once the patient is lying down and tumescent anaesthesia has been administered the contours can change dramatically. 2. There should be at least 1.5 cm of fat in the pinch test in the area to be treated (fig. 10.4). The decision must be made whether suction will be employed after laser lipolysis. In smaller areas like the submental region and inner thighs suction is not required while larger areas like the abdomen usually benefit from suction. 3. The procedure is performed under tumescent anesthesia. For this, a tumescent solution is prepared using lignocaine with epinephrine, sodium bicarbonate, and normal saline. The concentration of the lignocaine is between 0.05–0.1% depending the region being treated and that of 1:1,000,000 epinephrine is usually 0.05–0.75 mg/L. 10 meq of sodium bicarbonate is added to each liter of the tumescent solution to raise its pH and thus prevent stinging (lignocaine is acidic in nature). The maximum safe dose of lignocaine in tumescent anesthesia is 55 mg/ kg; however, experts recommend keeping the concentrations at a more conservative 35–45 mg/kg for additional safety. 4. The next step is to make access ports around the area to be treated. These can be made as small stab incisions with a No.11 blade or with a 1.5 mm punch, after infiltrating 1 ml of 1–2% lignocaine with 1:100,000 epinephrine at each site. The number of ports depends on the area being treated and a typical number for the abdomen is 4–6. The tumescent solution is then infiltrated gradually into the entire area to be treated. This can be done using large syringes (50 ml) or with specialized

Noninvasive Body Contouring  353

Fig. 10.4: Preoperative preparation for laser assisted liposuction (QuadroStar+ 980 (Diode laser)

devices, such as infiltration pressure cuffs. Because of the large volume required in areas, such as the abdomen (2–3 L), this step can take 45–60 minutes or more. About 30 minutes must be given after all the solution has been infiltrated to allow proper diffusion and adequate anesthesia before commencing the procedure. 5. After this, the fiberoptic cable carrying the laser is inserted through stainless steel cannulas and then introduced in the subcutaneous plane. The cannulas can be inserted empty to begin with and a tunneling to and fro motion used to create an easier path, once the laser is introduced. The laser cable extends 2 mm beyond the steel tip of the cannula and is visible as a bright red light shining through the skin. As the laser is fired the cannula is moved slowly to cover the treatment field. On an average 10 passes are required to adequate laser lipolysis. There is a reduction in volume of the treated area, felt with the finger pinch test, and this serves as a tactile marker of the end point for lasing (fig. 10.5). 6. Once this is done the suction apparatus is attached to the stainless steel cannulas and the liquefied fat from the laser treated areas is aspirated.

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Fig. 10.5 : A depiction of the procedure planes in laser assisted liposuction

Typically 2–5 L of fat can be removed from areas, such as the abdomen. This step takes 1.5–2 hours to complete. 7. In the end, the ports are dressed (not sutured) and a compression garment is applied to support the treated area. The patient is then sent home on antibiotics and painkillers.

Advantages of Laser-assisted Liposuction 1. Shorter recovery time. Most patients able to go back to work within 2–3 days. 2. Less bruising and edema and hence, less post-procedure pain. 3. Less trauma during the procedure due to smaller size of the cannula used. 4. Skin tightening is perhaps the most important benefit of LAL as compared to suction assisted liposuction (SAL). 5. More uniform fat reduction and hence smoother external appearance. 6. Lower rate of revision surgeries (3.5% as compared to 12–13% with SAL). 7. Limited role in improving cellulite as compared to SAL, which is ineffective for this indication.

Limitations of Laser-assisted Liposuction

1. 2. 3. 4. 5.

High cost of the laser machine. Increased procedure time as compared to SAL. Risk of thermal injury (skin burns). Unsuitable to treat large areas. Steeper learning curve as compared to suction-assisted liposuction.

Noninvasive Body Contouring  355

Summary Laser lipolysis is a new technique still under development. The use of 1,064 nm-Nd:YAG and the 980-nm diode laser as an auxiliary tool has refined the traditional liposuction technique. For given energy settings, 1,064 and 980nm wavelengths gave similar histologic results (figs 10.6A and B). Recently DiBernardo reported that the use of a 1440 nm laser subdermally could disrupt and reduce herniated fat in the dermis, through a process of tissue coagulation. They demonstrated ultrasound evidence of a 25% increase in skin thickness and a 29% decrease in skin laxity, which was maintained at 1 year. We are particularly impressed with the study of Katz et al. where a single treatment with the Nd:YAG 1440 nm wavelength laser was analyzed by objective 2D and 3D photography (Vectra). Of patients, 62% showed improvement at 3 months and 66% showed improvement at 6 months. There are numerous advantages of LAL and it is a useful adjunct to tumescent liposuction. But the smaller size of cannulas limits the ability of this technology to be used on areas other than face, medial arms, knees, periumbilical, and perhaps medial thighs as a sole treatment.

Selective Cryolipolysis There is evidence that adipose tissue is selectively sensitive to cold injury. This is akin to cold-induced fat necrosis of the newborns and infants called “popsicle panniculitis” and is the basis of this therapy (Box 10.1)

A

B

Figs 10.6A and B: (A) A 28-year-old female with localized adiposity in the lower anterior abdomen and flanks; (B) Same patient 10 days after laser assisted liposuction demonstrating a 3.5 inch circumference loss with minimal skin laxity and no bruising. The access ports are visible on either side of the umbilicus and will gradually fade over 3–6 months. The abdominal skin will also tighten with time

356  Lasers in Dermatological Practice

How does it Work? Cryolysis of fatty tissue is possible due to this biological selectivity. Biologic selectivity refers to a specific response (e.g. inflammation) that is confined to a certain tissue (e.g. fat) on account of a stimulus. Studies have revealed that a delayed, cold-induced lobular panniculitis is involved. The adipose tissue loss continues for many weeks following a single, local exposure to cold, reaching an apparent maximum at 4 weeks after and resolving about 3 months after cold exposure. Temperature and time of application are both important to induce selective cryolysis of fatty tissue. A skin surface temperature as high as −1°C induced can induce a mild panniculitis within the various tested anatomical locations and the anatomic depth of panniculitis and of fat loss is increased when lower temperatures are applied.

Results and Summary Work done by Anderson et al. has suggested that lipid crystallization is perhaps responsible for lipoatrophy seen in their Yucatan pig models. This mechanism will pose challenges to the development of selective cryolysis for clinical use, as pigs have a higher content of saturated fatty acids compared to unsaturated ones. Additionally, it is not apparent that the intracellular crystals seen in adipocytes were large enough to elicit the inflammatory panniculitis, largely responsible for producing the effects. Zeltiq (Zeltiq Aesthetics, Pleasanton, CA, USA) is the main cryolipolysis device available in the market and is FDA approved for treating the abdominal flanks (love handles). The part to be treated is sucked into the probe with mild suction and then held between the panels for 30–60 minutes at a sub zero temperature. Once the probes are removed, the area is red and feels frozen solid and numb. This numbness can persist for 2–3 months but there are no reports of permanent nerve damage. Studies have shown a 25% reduction in the fat content of the treated areas. No systemic side effects have been seen. The machine does not require a technician to operate but has the disadvantage of long treatment time and a high disposable cost.

Conclusion Many important details about selective cryolysis remain to be studied. Most importantly, there is not enough information available in published literature regarding the mechanisms of adipocyte injury in adult humans when subzero temperatures are applied to a fold of skin suctioned in between two cold applicators, for varying times. At this point, we know little or nothing about the longevity of the fat lost as a result of selective cryolysis. The possibility of fat regenerating itself after a certain period of time still remains. Finally, there is a question of the “fate of fat.” Although in the study done by Anderson et al.

Noninvasive Body Contouring  357

no significant rise in serum lipids was seen, the possibility of fatty infiltration of liver cannot be excluded. Cryolipolysis represents a novel, non-invasive treatment option for fat. Patients can undergo a safe, effective, and simple procedure, which will gradually reduce the appearance of unwanted fat over the following 2–4 months. It should be noted that the device works best for localized, discrete fat bulges and is not intended for the treatment of obesity or as a substitute for large-volume liposuction.

Acoustic Waves These are radial mechanical wave, which have penetration depth of about 25–30 mm. A comparison with comparator technologies is depicted in Figure 10.7. The acoustic wave (a particular family of shock waves) penetrates the skin (fig. 10.7) and the maximum energy density is at the surface and rapidly decreases with increasing penetration (with 1/r²). They are used for local fat deposits and work by: 1. Altering the Osmotic balance. 2. Improvement of intra-/extracellular metabolism. 3. Increase in cellular metabolism in the adipose tissue. 4. Improved tone of connective tissue.

Indications Localized fat deposition on the upper arm, abdomen, hips, buttocks, thighs, and inner thighs.

Results Various studies have been published on this technology largely from Europe, which show that the technology is effective in localized cases of cellulite. But more studies are needed to validate these findings (Fig. 10.8).

Fig. 10.7: A comparison of acoustic waves with different ultrasound systems

358  Lasers in Dermatological Practice

Fig. 10.8: A case of localized adipose tissue deposition treated by AW technology (Ascepelion laser technologies, GmBh)

Issues and Controversies with NonSurgical Sculpting Cellulite is a well-documented condition, and although many treatment options have been used, few have lasting clinical results. This historically notorious problem will always be the focus of device technologies, but considering the multiple mechanism involved in cellulite, we feel that technology may not by itself help in this condition. Depending on the grade and severity, some cellulite patients may see a lesser degree of improvement. It is important in the consultation to address patient expectations. Noninvasive treatments require multiple treatments as well as possible interval maintenance treatments. Resistant cases could be due to severity of the case or undertreatment of the area. When using laser, radiofrequency, or ultrasound devices, it is important not to deliver excessive fluences, as this could lead to unwarranted treatment, complications, and/or thermal damage. There are other issues, which have to be ironed out. It is important to see all patients in follow-up. Measurements to be taken include dimple severity, circumference, and overall laxity. Patient satisfaction should also be assessed. The use of traditional 2D imaging as well as 3D imaging can augment followup visits. Patient satisfaction to be given an objective comparison from baseline. The controversies and unanswered questions with regard to laser lipolysis are many and include lack of standardized treatment protocols and the amount of the tumescent fluid to be used in laser-assisted liposuction. If too little fluid is used, the anesthesia is incomplete. If a proper “supertumescence” is applied, much of the laser energy is absorbed by the infiltrated fluid instead of the tissue. The most effective energy that can be delivered with the fewest side effects has not been determined. Lastly, the best way to move the handpiece through the subcutaneous tissue: release of the laser energy only when pulling back or during a back and forth movement; moving slowly and evenly or faster and in a more random way is another vexing issue.

Noninvasive Body Contouring  359

Thus, at present laser lipolysis is to be used mostly in conjunction with tumescent liposuction. Because the same risks and side effects apply, the surgeon should be well trained and experienced in liposuction surgery and untrained dermatologists should not venture into the invasive procedures. As fat reduction is a cosmetic and commercial necessity, a lot of refinements are needed, and thus, this will continue to be a topic of active future research. Thus, at present with little comparisons between the various methods, it is difficult to decide which is the ideal device. But if a substantial end result is the aim, laser-assisted liposuction seems to be the best bet at present in our opinion.

Bibliography 1. Alam M, Dover JS; ASDS Dermatologic Surgery Lexicon Task Force. American Society for Dermatologic Surgery dermatologic surgery drug and device nomenclature recommendations. Dermatol Surg. 2013;39(8):1158-66. 2. Anderson RR, Farinelli W, Laubach H, et al. Selective photothermolysis of lipidrich tissues: a free electron laser study. Lasers Surg Med. 2006;38(10):913-9. 3. Boris Sommer, Dorothee Bergfeld. Laser-Assisted Liposuction. In C Raulin and S Karsai (eds.); Laser and IPL Technology in Dermatology and Aesthetic Medicine, DOI: 10.1007/978-3-642-03438-1_8, © Springer-Verlag Berlin Heidelberg 2011. 4. Christ C, Brenke R, Sattler G, Siems W, Novak P, Daser A. Improvement in skin elasticity in the treatment of cellulite and connective tissue weakness by means of extracorporeal pulse activation therapy. Aesthet Surg J. 2008;28(5):538-44. 5. DiBernardo BE. Treatment of cellulite using a 1440-nm pulsed laser with oneyear follow-up. Aesthet Surg J. 2011;31(3):328-41. 6. Goldberg D, Fazeli A, Berlin A. Clinical, laboratory and MRI analysis of cellulite treatment with a unipolar radiofrequency device. J Dermatol Surg. 2008; 34(2):204-9. 7. Ichikawa K, Miyasaka M, Tanaka R, et al. Histologic evaluation of the pulsed Nd:YAG laser for laser lipolysis. Lasers Surg Med. 2005;36:43-46. 8. Katz BE, Quantitative and Qualitative Evaluation of the Efficacy of a1440 nm Nd:YAG laser with novel bidirectional optical fiber in the treatment of cellulite as measured by 3-dimensional surface imaging. J Drugs Dermatol. in press. 9. Manstein D, Laubach H, Watanabe K, Farinelli W, Zurakowski D, Anderson RR. Selective cryolysis: a novel method of non-invasive fat removal. Lasers Surg Med. 2008;40:595-604. 10. Mulholland RS, Paul MD, Chalfoun C. Noninvasive body contouring withradiofrequency, ultrasound, cryolipolysis, and low-level laser therapy. Clin Plast Surg. 2011;38(3):503-20. 11. Neira R, Toledo L, Arroyave J, et al. Low-level laser-assisted liposuction: the Neira 4 L technique. Clin Plast Surg 2006;33(1):117-27. 12. Nootheti PK, Magpantay A, Yosowitz G, Calderon S, Goldman MP. A single center, randomized comparative, prospective clinical study to determine the efficacy of the VelaSmooth system versus the triactive system for the treatment of cellulite. Lasers Surg Med. 2003;38:908-12.

360  Lasers in Dermatological Practice 13. Neira R, Ortiz C. Low level laser assisted liposculpture: clinical report of 700 cases. Aesthet Surg J. 2002;22:451-55. 14. Nurnberger F, Muller G. So-called cellulite: an invented disease. J Dermatol Surg Oncol. 1978;4:221-9. 15. Rossi AM, Katz BE. A modern approach to the treatment of cellulite. Dermatol Clin. 2014;32(1):51-9. 16. Russe-Wilflingseder K, Russe E, Vester JC, Haller G, Novak P, Krotz A. Placebo controlled, prospectively randomized, double-blinded study for the investigation of the effectiveness and safety of the acoustic wave therapy (AWT) for cellulite treatment. J Cosmet Laser Ther. 2013;15(3):155-62. 17. Sadick NS, Mulholland RS. A prospective clinical study to evaluate the effi cacy and safety of cellulite treatment using the combination of optical and RF energies for subcutaneous tissue heating. J Cosmet Laser Ther. 2004;6:187-90. 18. Teitelbaum  SA,  Burns  JL,  Kubota  J, et al. Noninvasive body contouring by focused ultrasound: safety and efficacy of the Contour I device in a multicenter, controlled, clinical study. Plastic and Reconstructive Surgery. 2007;120(3):77989. 19. van Veen RL, Sterenborg HJ, Pifferi A, Torricelli A, Chikoidze E, Cubeddu R. Determination of visible near-IR absorption coefficients of mammalian fat using time-and spatially resolved diffuse reflectance and transmission spectroscopy. J Biomed Opt. 2005;10:054004.

Chapter

11

Lasers for Scars, Keloids, and Stretch Marks Kabir Sardana

Introduction The psychosocial impact of cutaneous scarring can be profound. The multifaceted causes of scars include traumatic incidents,surgical procedures, and severe acne and can profoundly affect the quality of life of patients. We will largely focus on the role of laser in nonacne scars in this chapter. Acne scar have been discussed in the chapter of Fractional lasers.

EtioPathogenesis Scars are the result of a deviation in the orderly pattern of healing and can be caused by a variety of factors, such as excessive wound tension, improper surgical repair, delayed reepithelialization, or a history of radiation to the affected area. An excessive tissue response can create a raised nodule of fibrotic tissue, whereas “pitted” and atrophic scars may result from inadequate replacement of deleted collagen fibers. There are several currently available scar reducing medical therapies, but we will largely focus on lasers.

Types of Scars In medical literature, scars are often analyzed by their etiology, the most common sources being surgery, trauma, burns, and acne or inflammatory processes. While analyzing literature, the important parameters to assess improvement include reduction of the redness and height of the scar, improvement of pliability, and symptomatic relief of pruritus.

Hypertrophic Scars They are erythematous, raised, firm nodular growths that occur more commonly in areas subject to increased pressure or movement or in body sites that exhibit slow wound healing. The growth of hypertrophic scars is limited to the site of original tissue injury, unlike keloids, which proliferate beyond the boundaries of the initial wound and often continue to grow without regression.

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Keloids Keloids present as deep reddish-purple papules and nodules, often on the earlobes, anterior chest, shoulders, and upper back. These lesions are more common in darker-skinned persons and, like hypertrophic scars, may be pruritic, dysesthetic, and cosmetically disfiguring. Whereas the histology of hypertrophic scars is indistinguishable from that of other scarring processes, keloidal histology may be recognized by thickened bundles of hyalinized acellular collagen haphazardly arranged in whorls and nodules with an increased amount of hyaluronidase. There are a few salient differences between these two scars that are as follows: 1. Hypertrophic scars are generally white to pink scars that remain within the borders of the original wound. 2. These generally occur within 1 month of the injury and tend to improve over time. 3. Keloids are composed of disorganized, thick, collagen fibers with a prominent mucoid matrix. Hypertrophic scars contain more organized collagen fibers within a scant mucoid matrix.

Atrophic Scars These are dermal depressions that result from an acute inflammatory process affecting the skin, such as cystic acne or varicella. The inflammation associated with atrophic scars leads to collagen destruction with dermal atrophy. Surgery or other forms of skin trauma may also result in atrophic scars, which are initially erythematous and become increasingly hypopigmented and fibrotic over time. Based on their width, depth, and 3-dimensional architecture, acne scars are sometimes further subclassified into icepick, rolling, and boxcar scars. They are discussed in the chapter on fractional lasers.

Prescars These are early wounds in scar-prone skin. Prophylactic or early laser treatment of traumatized skin concomitant with or shortly after cutaneous wounding has been shown to reduce or even prevent scar formation in patients at high risk for scarring.

Approach to Therapy The scars should be treated depending on the type, stage, duration, color and taking into consideration patient characteristics. Thus, an algorithmic approach can be used (Flow chart 11.1) to first decide which laser to use, which can then be tweaked depending on patient characteristics (Table 11.1). But, it must be appreciated that hypertrophic scars, if left alone, tend to improve with time, and most of the studies published may have inadvertently overlooked this fact.

Lasers for Scars, Keloids, and Stretch Marks  363 Flow chart 11.1: An overview of management of scars by lasers

Table 11.1 Parameters that determine laser therapy for scars Characteristics

Variables

First line

Second line

Severity

Mild

Nonablative lasers

Ablative lasers

Moderate

Ablative lasers

Fractional (NAFR)

Severe

Ablative lasers

Fractional (AFR)

Type 1–3

All are equally good

Type 4–6

Fractional lasers

Skin type Etiology

Patient choice

Burn scar

PDL

Fractional lasers

Surgical scar

Fractional lasers

PDL/ablative

Acne scar

Fractional lasers

Minimum downtime

Nonablative lasers

Some downtime

Fractional (NAFR)

Can tolerate downtime

Ablative lasers

Ablative (CO2/Er:YAG), Fractional (NAFR/AFR)

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Most of the hypertrophic scars have an average of 50–80% improvement after two laser treatments. Keloids, however, usually require more treatments and/or other ancillary treatments, including surgical excision, to achieve acceptable results.

Hypertrophic Scars and Keloids Laser used: PDL, fractional laser, LED, PDT. Initial studies used 1064 nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser, argon, and carbon dioxide (CO2) showed promising results, but high recurrence rates were observed. Thus, the most commonly recommended system is the PDL, though it makes more sense to stratify therapy according to the type of scars.

PDL (Brewin MP 2014, Mamalis AD 2013) PDLs have been shown to help in improving scar size, erythema, pliability, pruritus, and texture and is used for all forms of hypertrophic scarring and keloids, regardless of etiology.

Indications Burn scars, sternotomy scars, acne scars, and facial scars resulting from cutaneous surgery.

Mechanism of Action 1. Reduce expression of transforming growth factor beta, fibroblast proliferation, and collagen type III deposition. 2. Selective photothermolysis of vasculature. 3. Modulation of released mast cell constituents (such as histamine and interleukins) that could affect collagen metabolism. 4. Heating of collagen fibers and breaking of disulfide bonds with subsequent collagen realignment.

Procedure Patient characteristics 1. History of the scar or keloid in terms of age, evolution, and previous treatments.

Preoperative If topical anesthesia is desired, a lidocaine-containing cream or gel can be applied to the treatment areas 30–60 minutes before laser irradiation. Wear protective goggles.

Lasers for Scars, Keloids, and Stretch Marks  365

Intraoperative 1. Skin should be cleansed with soap and water to remove residual makeup, powder, or creams. Flammable solutions, such as alcohol, should be avoided in skin preparation. 2. Wet gauze may be used to protect hair-bearing areas during treatment and to avoid unnecessary thermal injury to nontargeted skin. 3. A Test spot should be employed and if there is postoperative crusting or vesiculation, the fluence applied on subsequent visits should be decreased and retreatment postponed until the skin has completely healed. The fluence and pulse duration can be adjusted if scar proliferation continues despite laser irradiation. Generally speaking, higher fluences and shorter pulse durations result in improved scar size and pliability. Dose: In general, hypertrophic scars and keloids are treated with moderately low energy densities ranging from 6.0 to 7.5 J/cm2 (5 or 7 mm) or 4.5 to 5.5 J/cm2 (10 mm spot size). Pulse durations ranging from 0.45 to 1.5 milliseconds are commonly used. Energy densities should be lowered by at least 0.5 J/cm2 in patients with darker skin and for scars in delicate or thin-skinned locations (e.g. eyelids, neck, chest). The entire surface of the scar is treated with adjacent, nonoverlapping laser pulses. 4. Laser treatments are typically repeated at 6–8 week time intervals.

Postoperative A topical healing ointment under a nonstick bandage can be applied for the first few postoperative days to protect the skin. Treated areas should be gently cleansed daily with water and mild soap. Strict sun avoidance and photoprotection should be advocated between treatment sessions to reduce the risk of pigment alteration. Topical bleaching agents (such as hydroquinone or kojic acid) may be applied to hasten pigment resolution.

Pearls/Pitfalls 1. It is ideal to treat hypertrophic scars early, possibly within the first few months of appearance. 2. Previous treatments, such as cryotherapy, may cause increased fibrosis, and thus adjustments of laser parameters and treatment sessions may need to be made. 3. Location of the scar is also important to note. Dierickx et al. have found that facial scars respond better to treatment. Nouri et al. have also found that facial, shoulder, and arm scars respond better than those on the anterior chest wall. 4. Laser treatment may be used alone or in combination therapy with intralesional corticosteroids or 5-FU. Alster (2003) compared PDL

366  Lasers in Dermatological Practice

treatment alone with laser therapy combined with intralesional corticosteroid treatment and found that both were similarly effective with no significant difference. 5. The use of concomitant intralesional corticosteroids or 5-fluorouracil has been shown to provide additional benefit in proliferative scars. Intralesional injections of corticosteroids (20 mg/mL triamcinolone) are more easily delivered immediately after (rather than before) PDL irradiation because the laser-irradiated scar becomes edematous (making needle penetration easier). An additional consideration is that when steroid injection is performed before laser irradiation the skin blanches, rendering the skin a potentially less amenable target for vascular-specific irradiation.

Results The appearance of most hypertrophic scars will improve by approximately 50% after 2 treatments. Keloids often require additional treatment sessions to achieve significant improvement, but some may prove unresponsive.

Side Effects 1. The most common side effect of treatment with the PDL is postoperative purpura, which often persists for several days. Pulse durations shorter than 6 milliseconds are almost certain to bruise the skin. 2. Edema of treated skin may also occur but usually subsides within 48 hours. 3. Hyperpigmentation has been reported with varying frequencies. If skin darkening occurs, further laser treatment should be suspended until resolution of the dyspigmentation has occurred in order to reduce the risk of cutaneous melanin interference with laser energy penetration.

Fractional Laser Nonablative fractional photothermolysis with near infrared 1,540 and 1,550 nm erbium-doped fiber lasers is a promising new modality for the treatment of hypertrophic scars. But these may help in textural improvement and are not likely to affect the scar quality specially in keloids. Thus, as stated above studies should be analyzed with respect to, redness and height of the scar, improvement of pliability, and symptomatic relief of pruritus as these constitutes substantial improvement.

NAFR (1,550 nm Erbium-doped Fiber Laser) Niwa AB, et al. demonstrated significant improvement after two to three treatments, with improvement in pigmentation in all eight hypertrophic scars evaluated. The dose used was from 35 to 50 mJ, and 8 to 10 passes were

Lasers for Scars, Keloids, and Stretch Marks  367

applied with treatment levels 6–8 . The ultimate evaluation was doen by the quartile scoring system Haedersdal M, et al. used a 1,540 nm nonablative fractional laser (Starlux, Palomar Medical Technologies, Burlington, Mass., USA) in 17 burn scars (five with meshed split-thickness skin grafting) and showed significant textural improvement after three treatments.

AFR Ablative fractional resurfacing lasers have been used in the treatment of hypertrophic scars especially after burn cases (Haedersdal M).

Conclusion One of the most common indications is in the treatment of burn scars (Hultman CS, et al.). Restoration of form and function after burn injury remains challenging, but traditional and emerging laser and light-based technologies may offer new hope for patients with burn scars. Depending upon the constellation of patient symptoms and functional deficits, treatment of the burn scar involves a number of modalities, which may include massage and moisturizing agents, pressure garments, silicone sheeting, topical and intralesional steroids, and experimental therapies, such as interferon. The three different laser and light-based technologies are now increasingly being used in the management of burn scars. i. Vascular-specific pulsed dye laser (PDL) therapy to reduce hyperemia and hypertrophic scar formation. ii. Ablative fractional CO2  laser resurfacing to help correct the abnormal texture, thickness, and stiffness of the burn scar. iii. Intense pulsed light (IPL) therapy to improve burn scar dyschromia and alleviate chronic folliculitis. Thus, it must be emphasized that the fractional laser may be one tool to help in targeting an aspect of the scar and a multifaceted team approach is needed for significant improvement.

Atrophic Scars Laser used: Ablative lasers, nonablative lasers and fractional lasers. Atrophic scars resulting from acne, chickenpox, trauma, can be treated with laser therapy, though the results depend on numerous factors. Atrophic scars are initially erythematous and with time become increasingly fibrotic and hypopigmented. It is believed that atrophic scars result from inflammatory destruction of collagen with resultant dermal atrophy. Thus the tissue defect has to be targeted and explains why methods like subcision are of little use in chickenpox scars. Newer ablative resurfacing in the “spot” mode is our favoured mode of therapy. Nonablative resurfacing is considered safe but is not as effective as

368  Lasers in Dermatological Practice

ablative resurfacing. Fractional resurfacing offers the effectiveness of ablative resurfacing and the safety of nonablative resurfacing.

1. Ablative Lasers Though this has been detailed previously in the chapter of ablative lasers a overview will be given here. The advantages of this modality include selective and reproducibly vaporization of skin with improved operator control and clinical efficacy. This is achieved by the novel devices including , high energyshort pulsed CO2 laser,the variable pulsed or dual-mode erbium YAG laser and the combined-mode Erbium YAG/CO2 laser system.

Treatment Goal Laser treatment of atrophic scars is aimed at reducing the depth of the scar borders and stimulating neocollagenesis to fill in the depressions. Mostly spot (or local) vaporization of isolated scars is used as full face resurfacing is not practiced nowadays.

Procedure Preoperative: Various anesthetic options can be employed, though for spot ablation local anesthesia is used. Intraoperative: The CO2 laser is generally used at fluences of 250 to 350 mJ to ablate the epidermis in a single pass. Short-pulsed Er:YAG lasers that are operated at 5 to 15 J/cm2 often require several passes to result in a similar depth of penetration as CO2, whereas longer-pulsed Er:YAG systems can be operated at higher fluences (22.5 J/cm2) to achieve comparable results in a single pass. Though the details have been discussed previously in the chapter of Ablative Lasers, the basic steps are as follows: 1. Remove the epidermis over the scar (1–2 passes). 2. Focus around and over the scar shoulder and ablate it carefully to the level of the base of the scar. 3. Give a pass over the center of the scar. Postoperative: Postoperative erythema typically lasts several weeks after ablative laser treatment. Hyperpigmentation is transient and generally appears 3–4 weeks after treatment. Its resolution can be hastened with the use of topical bleaching agents.

Pearls Ablative Er:YAG lasers may be the preferred treatment for mildly atrophic scars, whereas ablative CO2 lasers may be preferable for more extensive scarring. But, it is our view that a dual mode Er:YAG can achieve results comparable to that of CO2.

Lasers for Scars, Keloids, and Stretch Marks  369

2. Nonablative Lasers As a consequence of the side effects and prolonged postoperative recovery associated with ablative laser treatment, nonablative lasers were subsequently developed to provide a noninvasive option for atrophic scar revision. But it must be emphasized that the results are slower and less dramatic than ablative lasers.

Devices and Lasers ¾¾ ¾¾ ¾¾ ¾¾ ¾¾

1,064 nm Q-switched Nd:YAG laser /1,064 nm Long pulse Nd:YAG laser 1,320 Nd:YAG laser 1,450 nm diode laser 1,540-nm erbium-doped phosphate glass laser (Er:Glass) 585 nm PDL and Intense pulse light system. Although, protocols vary, treatments are generally performed at monthly intervals for three consecutive months. Best results are observable 3–4 months after the last treatment.

Mode of Action These devices deliver concomitant epidermal surface cooling with deeply penetrating infrared wave-lengths that target tissue water and stimulate collagen production via controlled dermal heating without epidermal disruption. It is possible that the absorption of the 1,064 nm wavelength by the blood vessels in the scar may lead to either conduction to the surrounding dermis to alter the fibrotic collagen within the scar or to significant ischemia within the laser-treated tissue to affect collagen or release collagenase.

Results A series of 3–5 treatments are typically performed on a monthly basis, with optimal clinical efficacy appreciated several (3–6) months after the final laser treatment session. Sustained clinical improvement of scars by 40 to 50% has been observed after the series of treatments. The low side-effect profile of these nonablative systems (limited to local erythema and edema and, rarely, vesiculation or herpes simplex reactivation) compensates for their reduced clinical efficacy (relative to ablative lasers).

Conclusion The results of the nonablative resurfacing depend on the patient’s own woundhealing capacities and, as stated before, will not equal those obtainable with ablative treatments.

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3. Fractional Lasers Though this has been discussed in detail previously, our focus is primarily on nonacne scars, namely, chickenpox and smallpox scars. As the thermal coagulation required for ameliorating the tissue defect is more than what is required for acne scars, the dose settings have to be more aggressive than normal, which can be a issue as the side effects are also proportionately more.

Procedure Preoperative The ideal patient for fractional laser skin resurfacing has a fair complexion (skin phototype I, II, or III), but darker skin tones (IV–VI) can also be treated. Sun exposure should be avoided prior to treatment in order to decrease the risk of postoperative dyspigmentation. For patients with a strong history of herpes labialis, prophylactic oral antiviral medications should be considered when treating the perioral skin. Reactivation of prior herpes simplex infection can occur despite absence of an external wound, due to the intense dermal heat produced by the laser. Intraoperative 1. The treatment areas should be cleansed of debris (including dirt, makeup, and powder) using a mild cleanser and 70% alcohol. 2. A topical anesthetic cream is applied to the treatment sites for 60 minutes before treatment. 3. NAFR can be done by using a dose setting of 40–60 mJ ( maximum 70 mJ; total 3–5 kJ) Retreatments with gradually higher fluences should be performed at 4-week intervals until patients are satisfied with clinical outcomes (typically 3–5 sessions are necessary to produce substantial clinical improvement). 4. AFR require 1–2 sessions Fraxel repair: 20–100 mJ with treatment densities of 600–1600 MTZ/cm2. Lumenis system (Total Fx): (Deep FX: 15–25 mJ, active FX: 80–125 mJ) and densities (Deep FX: 10–15%, active RX: 1–3%) depending on the severity of scarring. Postoperative 1. Patients who receive NAFR treatment should use a mild cleanser and moisturizer several times daily for the first few days after each treatment session (or as long as bronzing/xerosis is apparent). 2. Sun exposure should be avoided during this time.

Conclusion Both ablative and nonablative fractionated lasers can be used and can help to resolve both textural and pigmentary changes. The latter is important as

Lasers for Scars, Keloids, and Stretch Marks  371 Table 11.2 Dose parameters for scar treatment for lasers Condition

Laser

Settings

Hypertrophic scars

585 – 595 nm PDL

6.0–7.5 J/cm2 (7 mm spot) or 4.5–5.5 J/cm2 (10 mm spot) 1.5–3 ms

CO2 (10600 nm)

1 pass, 300 mJ, 60 watts, 5 J/cm2

Er:YAG (2940 nm)

2–3 passes, 5 mm spot size, 5–15 J/cm2

Fractional CO2

DeepFXTM: thick, stiff scar,: density of 15%, frequency 600Hz, 12.5–17.5 mJ per micropulse. ActiveFXTM : Textural: frequency of 150 Hz, 70–90 mJ per micropulse. 

585 – 595 nm PDL

6.0–7.5 J/cm2 (7 mm spot) 4.5–5.5 J/cm2 (10 mm spot) 1.5–3 ms

CO2 (10600 nm)

1 pass, 300 mJ, 60 watts, 5 J/cm2

Er:YAG (2940 nm)

2–3 passes, 5 mm spot size, 5–15 J/cm2

Non-ablative fractional (1540/1550 nm)

15 mm handpiece, 35–50 J/cm2

CO2 (10 600 nm)

1 pass, 300 mJ, 60 watts, 5 J/cm2

Er:YAG (2940 nm)

2 – 3 passes, 5 mm spot size, 5 – 15 J/cm2

Diode (1450 nm)

8 – 14 J/cm2 , 250 ms, 6 mm spot size

Nd:YAG (1320 nm)

18 J/cm2 , 200 μs, 6 mm spot size

Keloids

Atrophic scars (surgical or trauma)

Box 11.1

Principles of laser therapy for scars

1. Keloids may be responsive only in the early stage. In late stage once the keloid becomes firm and hard the PDL is not very useful. Even though various other lasers have been tried the results are not satisfactory. 2. Hypertrophic Scars are easy to treat. A combination of PDL followed by Fractional CO2 can be used. 3. Atrophic scars are best treated by an ablative laser. Nonablative NIR lasers and fractional lasers are slower in action and incomplete in results. 4. Traditional medical therapies can be combined with lasers (Waibel JS, et al.)

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with most ablative treatments hypopigmentation and even depigmentation is seen.

Prescars Treatment of potential scars with lasers is a relatively new concept that is gaining in popularity. Two different approaches for scar prevention within prescars have been outlined. Wound edges can be vaporized with either a CO2 or an Er:YAG laser before primary surgical closure to enhance ultimate cosmesis. Alternatively, a 585 nm PDL system can be used to treat surgical sites, traumatic wounds or ulcerations to improve the quality of scarring and prevent excessive scar formation.

Conclusion Though lasers are now being used increasingly for treating scars, it must be emphasized that they are one of the many tools that can be adopted. Except for atrophic scars in most other indications, conventional modalities like IL steroids/FU can and should be combined with lasers. The cost, time, and effort required for results with lasers, do not justify their use in all cases. In burn cases the use of PDL± fractional lasers can be at best an adjunct to traditional modes of therapy. Thus, we favor using laser in additions to standard modalities. The issue of dermal fillers in the area to be treated is important. Studies have been done to determine the effect of different laser devices on skin previously treated with hyaluronic acid fillers (Farkas JP). Although the injected material was unaffected by the nonablative laser and intense pulsed light treatments, deeper laser treatments did demonstrate laser-filler interaction. The effect of this interaction is not yet known. Also, newer ablative and nonablative fractional lasers have the ability to penetrate deep into the dermis and, again, the effects this may have on the fillers is not yet known. Thus, care must be taken when planning to use lasers in combination with soft tissue fillers for the treatment of scars. A few principles are given in the Box 11.1, and a guide to dosimetry is given in Table 11.2 which can help guide the clinician to plan a therapeutic intervention.

Bibliography 1. Alster T, Zaulyanov L. Laser scar revision: a review. Dermatol Surg. 2007 2. Alster T. Laser scar revision: comparison study of 585-nm pulsed dye laser with and without intralesional corticosteroids. Dermatol Surg. 2003;29(1):25-9. 3. Brewin MP, Lister TS. Prevention or treatment of hypertrophic burn scarring: A review of when and how to treat with the Pulsed Dye Laser. Burns. 2014; pii: S0305-4179(13)00442-7.

Lasers for Scars, Keloids, and Stretch Marks  373 4. Choi JE, Oh GN, Kim JY, Seo SH, Ahn HH, Kye YC. Ablative fractional laser treatment for hypertrophic scars: comparison between Er:YAG and CO2 fractionallasers. J Dermatolog Treat. 2014;25(4):299-303. 5. Dierickx C, Goldman MP, Fitzpatrick RE. Laser treatment of erythematous/ hypertrophic and pigmented scars in 26 patients. Plast Reconstr Surg. 1995;95(1):84-90. 6. Haedersdal M, Moreau KE, et al. Fractional nonablative 1540 nm laser resurfacing for thermal burn scars: a randomized controlled trial. Lasers Surg Med. 2009;41(3):189–95. 7. Haedersdal M. Fractional ablative CO2 laser resurfacing improves a thermal burn scar. J Eur Acad Dermatol Venereol. 2009;23(11):1340–1. 8. Hultman CS , Edkins RE, Lee CN, Calvert CT, Cairns BA. Shine on: Review ofLaser- and Light-Based Therapies for the Treatment of Burn Scars. Dermatol Res Pract. 2012;2012:243651. doi: 10.1155/2012/243651. 9. Khatri KA, Mahoney DL, McCartney MJ. Laser scar revision: A review. J Cosmet Laser Ther. 2011;13(2):54-62. 10. Mamalis AD, Lev-Tov H, Nguyen DH, Jagdeo JR. Laser and light-based treatment of Keloids - a review. J Eur Acad Dermatol Venereol. 2013; doi: 10.1111/jdv.12253. 11. Niwa AB, Mello AP, et al. Fractional photothermolysis for the treatment of hypertrophic scars: clinical experience of eight cases. Dermatol Surg. 2009;35(5):773–7. 12. Nouri K, Jimenez GP, Harrison-Balestra C, et al. 585 nm pulsed dye laser in the treatment of surgical scars starting on the suture removal day. Dermatol Surg. 2003;29:65-73. 13. Ud-Din S, Bayat A. Strategic management of keloid disease in ethnic skin: a structured approach supported by the emerging literature. Br J Dermatol. 2013 Oct;169 Suppl 3:71-81. 14. Waibel JS, Wulkan AJ, Shumaker PR. Treatment of hypertrophic scars using laser and laser assisted corticosteroid delivery. Lasers Surg Med. 2013;45(3):135-40. 15. Westine JG, Lopez MA, Thomas JR. Scar revision. Facial Plast Surg Clin North Am. 2005;13(2):325-31, vii. Review

Striae Distensae Striae distensae or stretch marks are a common skin abnormality affecting both sexes and all races. These lesions usually evolve through various stages which are important to recognise before attempting any intervention Acute: The striae appear red or violaceous and are referred to as striae rubra. During this stage, they may be raised and often irritated. Chronic: Here the striae become white, atrophied, and depressed. At this stage, they are referred to as striae alba.

Role of Laser Treatment Although striae are a common cause of concern, highly effective, low-risk treatment modalities are lacking. These lesions are notoriously hard to treat. Many treatments have been tried and tested. Topical treatment with tretinoin

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cream 0.05%, l-ascorbic acid, and 20% glycolic acid have been shown to improve the clinical appearance of striae alba, and tretinoin 0.1% cream has been proven to improve the redness as well as length/width of striae rubra. However, none of these treatments have been proven to increase collagen or elastin production within the lesions. Ultraviolet (UV) B phototherapy has been used to improve the hypopigmentation observed in striae alba, but it does not correct the lesion’s atrophy

Lasers Used The principles of therapy are akin to those given under the section on scars , thus newer lesions responding much better than old ones. The laser used include flash-pumped 585 nm pulse dye laser, intense pulsed light, 308-nm excimer laser, nonablative 1,450 nm diode laser, radiofrequency device, 1,064 nm Nd:YAG laser, nonablative fractional CO2 resurfacing. The basic principles are (Fig. 11.1) photothermolysis, and ablative fractional 1. Early stages (Rubra): 585 and 595 nm PDLs. 2. Late Stages : (Alba) use subsurface lasers and fractional lasers. 3. Pigmentary alteration: excimer laser. 4. Lasers should demonstate both clinical improvement in depth and width and histological improvement with increase in the numbers of collagen and elastin fibers (Fig. 11.2). PDL: Should be used in striae rubra. In pigmented skin lower fluencies can lead to hyperpigmentation. One or two treatment sessions are necessary.

Fractional Lasers All the available technologies have been used including Er:Glass laser (1,550 nm), 1540 nm, Er:YAG and CO2 . Fractional photothermolysis creates multiple noncontiguous zones of thermal damage in the epidermis and dermis, sparing the tissue surrounding the wound. This in turn stimulates epidermal

Fig. 11.1: Overview of lasers and light devices for treating striae. Note that three aspects have to be treated the width, depth and color of the striae

Lasers for Scars, Keloids, and Stretch Marks  375

A

B

Pretreatment shows a thin epidermis while the post-treatment image shows an increase in the thickness of the epidermis with an increase collagen and elastin Figs 11.2A and B: A depiction of the histological effect of lasers on striae distensae

turnover and dermal collagen remodeling, which results in improvement of a variety of scar types. As all fractional lasers have water as a chromophore they are safe and we prefer using the 1540 nm as it has a relatively less absorption spectrum for water and thus can lead to more collagen remodelling. Dose: Use a low dose, high density setting spaced at 4–6 weeks. (Example:Lux Palomar. Treatment parameters included two to three passes with the 1540 nm laser, with energy settings from 35 to 55 mJ/mb with the 10 mm optical tip or 12–14 mJ/mb with the 15 mm optical tip).

Comparison As the depth of the pathology is in the upper dermis, as expected little difference is seen between NAFR and AFR (Yang YJ).

Other Devices IPL (590 nm), fractional RF and platelet rich plasma have also been tried.

Conclusion Its the authors opinion that the result with most devices has rarely been compared with a placebo group and there is a good chance that the patients may have spontaneous remission. If an intervention is desired any fractional device would suffice, with no advantage of ARR over NAFR. Conservative fluencies should be used to ensure a mid dermis depth .As the condition is akin to a atrophic scar a 30% decrease in fluence can be used of the conventional settings for acne scars. Do not hope for more than a 50% improvement. Proof of cure is histological and that is rarely done in most studies.

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Bibliography 1. Al-Dhalimi MA, Abo Nasyria AA. A comparative study of the effectiveness of intense pulsed light wavelengths (650 nm vs 590 nm) in the treatment of striae distensae. J Cosmet Laser Ther. 2013;15(3):120-5. 2. de Angelis F, Kolesnikova L, Renato F, Liguori G. Fractional nonablative 1540 nm laser treatment of striae distensae in Fitzpatrick skin types II to IV:clinical and histological results. Aesthet Surg J. 2011;31(4):411-9. 3. Gauglitz GG, Reinholz M, Kaudewitz P, Schauber J, Ruzicka T. Treatment of striae distensae using an ablative Erbium: YAG fractional laser versus a 585-nm pulseddye laser. J Cosmet Laser Ther. 2013 Nov 18. 4. Jiménez GP, Flores F, Berman B, Gunja-Smith Z. Treatment of striae rubra and striae alba with the 585-nm pulsed-dye laser. Dermatol Surg. 2003;29(4):362-5. 5. Suh DH, Lee SJ, Lee JH, Kim HJ, Shin MK, Song KY. Treatment of striae distensae combined enhanced penetration platelet-rich plasma and ultrasound after plasma fractional radiofrequency. J Cosmet Laser Ther. 2012;14(6):272-6. 6. Yang YJ, Lee GY. Treatment of Striae Distensae with Nonablative Fractional Laser versus Ablative CO2 Fractional Laser: A Randomized Controlled Trial. Ann Dermatol. 2011;23(4):481-9.

Section

3

Practical Aspects and Advances

Chapter

12

Miscellaneous Laser Responsive Disorders Kabir Sardana

Introduction There are numerous indications for lasers. Most of them are not approved indications as yet, but considering the liberal US FDA approvals, it is likely that they will be listed soon. We will give a brief overview of them and for sake on convenience are listing them alphabetically. Some of the indications like excimer light therapy for psoriasis and vitiligo are approved, but it is the authors’ opinion based on objective evaluation of studies that in tropical country with a high ambient UV flux, conventional phototherapy is a cost effective option with equal site specific efficacy. Other indication like the lasers for onychomycosis and hair growth are again approved but very few RCT have been published. However, as these devices are increasingly being used in practice an overview will nevertheless be given.

Acne Light-based therapies are an attractive alternative acne therapy because as they potentially offer more rapid onset and better patient compliance with a low incidence of adverse events. However, optimal treatment methods and the relative efficacy of light-based therapies as compared to traditional therapies remain unclear. Light-based acne therapies are generally thought to act via reducing Propionibacterium acnes proliferation or by targeting the sebaceous gland to reduce sebum production; however, other mechanisms may exist (Table 12.1).

Mode of Action Propionibacterium acnes produces endogenous porphyrins that are photoactivated, thus producing singlet oxygen species and free radicals that may result in bacterial destruction. Blue light results in the most pronounced photoactivation of endogenous porphyrins. However, its clinical efficacy is limited by a shallow depth of penetration. Combined blue and red light and photopneumatic therapy are

380  Lasers in Dermatological Practice Table 12.1 Summary of devices that have a role in acne therapy Inhibits P. acnes

Inhibits sebaceous gland

Inhibits sebaceous gland and P. acnes

Blue and red light

1,320-nm Nd:YAG laser

Photodynamic therapy

IPL

1,450-nm diode laser

Photopneumatic therapy

1,540-nm erbium:glass laser

532-nm KTP laser 585/595-nm PDL

among the potentially promising therapies for acne that are believed to work, at least in part, by targeting P. acnes. Infrared wavelength lasers are often able to treat acne by causing sebaceous gland alterations while preserving epidermal integrity. Variable clinical responses have been observed with the 1,450-nm diode, 1,320-nm neodymium:yttrium aluminum garnet, and 1,540-nm erbium:glass lasers that target sebaceous glands. Our own experience with the Er:Glass (Lux Palomar) has been that there is a certain degree of improvement of acne, but this cannot be a justification of using it for acne. A recent study has also found that fractional RF can help ameliorate active acne. Photodynamic therapy (PDT) is potentially an effective light-based acne therapy and may cause photodestruction of both P. acnes and sebaceous glands. The optimal photosensitizer, light source, and therapeutic protocol for PDT as a treatment for acne is unknown. However, noncoherent yellowred light has shown particular promise in some studies.

Summary Though the study design of many clinical trials in this area make it impossible to draw firm conclusions at this time, there is considerable evidence that light-based therapies that act via photodestruction of P. acnes may be capable of clinically improving acne. As light-based therapies are well tolerated and have a low incidence of adverse events they may be used as an adjunct to medical therapy.

Bibliography 1. Bogle MA, Dover JS, Arndt KA, et al. Evaluation of the 1,540-nm erbium:glass laser in the treatment of inflammatory facial acne. Dermatol Surg. 2007;33:810-7.

Miscellaneous Laser Responsive Disorders  381 2. Clark C, Bryden A, Dawe R, et al. Topical 5-aminolaevulinic acid photodynamic therapy for cutaneous lesions: outcome and comparison of light sources. Photodermatol Photoimmunol Photomed. 2003;19:134-41. 3. Lee KR, Lee EG, Lee HJ, Yoon MS. Assessment of treatment efficacy and sebosuppressive effect of fractional radiofrequency microneedle on acne vulgaris. Lasers Surg Med. 2013;45(10):639-47.

Benign tumors and Cysts Though most of these lesions have been discussed in the chapter on ablative lasers, a few uncommon indications are discussed here.

Epithelioma Adenoides Cysticum (Trichoepithelioma) This condition is characterized by small, colorless papules that are located mainly on nasolabial folds. Histologically they are hair follicle tumors (trichoepitheliomas). There are reports about successful treatment with the argon and CO2 lasers in individual cases. Recurrences depend on ablation depth and are part of the nature of the disease (Sajben FP, et al).

Fibrous Papule of the Nose These lesions are variously described as a fibroma or a regressive fibrosed nevus. These lesions, which occur mostly isolated on the tip of the nose, are essentially a cosmetic issue. Before laser therapy was introduced, excisions and cauterization were the therapy options. Due to the fibrous structure, ablation with the erbium:YAG or pulsed CO2 is an excellent choice. The pulsed dye laser and the argon laser can also be considered as a therapy option.

Koenen Tumors Laser vaporization of Koenen tumors with a CO2 laser proved to be similar to conventional surgical techniques in terms of cosmetic satisfaction. There are two advantages though of using this lasers, first is the lack of bleeding and second short operating time with excellent cosmetic and functional outcome.

Neurofibromas Treatment of neurofibromas can be done effectively with the continuous wave CO2 laser. After opening the epidermis, the neurofibroma can be pressed out and ablated. Removal should always be done completely down to the base to prevent quick recurrence. (Figs 12.1A to E).

382  Lasers in Dermatological Practice

A

B

C

D

E

Figs 12.1A to E: (A) A neurofibroma on the side of the nose; (B) Local anesthesia is given; (C) The Er:YAG (dermablate) is used to first abate the epidermis (7 J/cm2, 2 Hz); (D) The Er:YAG ablation is continued till bleeding occurs signifying lower papillary dermis. After this the pulsed CO2 is used to destroy the base; (E) Post-treatment photograph showing complete healing of the lesion

Miscellaneous Laser Responsive Disorders  383

Kardorff has published case reports about successful therapy of neurofibromas using the erbium: YAG laser in combination with surgical excision.

Seborrheic Keratoses Seborrheic keratoses are common benign, epidermal neoplasms that are very variable in number, size, and color. There are numerous methods of removal including electrofulguration. Among the lasers, this author favors the use of the Er:YAG as it ensures an accurate depth of penetration and excellent healing. A dose of 3–5 J/cm2 at 2 Hz gives rapid results (Dmovsek-Olup B). A single laser impulse is adequate for most lesions. Some wipe the area with normal saline, which helps to visualize the dermis, though it is better to leave the residue as it affords a biological healing and sheds-off in 3-5 days. A controlled superpulsed CO2 is another option (Fitzpatrick RE). The Q-switched ruby or neodymium (Nd):YAG lasers can also be used with good results for the treatment of flat pigmented seborrheic keratoses. The results depend on the thickness of the lesions, but one or two treatment sessions suffice in most cases.

Viral Disorders Though most viral disorders by nature are self-limiting with the most consistent results being mediated by immune modulation, destructive methods are often used, where lasers provide the best trade off between efficacy and side effects.

Lasers Used The CO2 laser light (wavelength of 10,600 nm) is mainly absorbed by water and enables vaporization of tissue of any kind. Because a CO2 laser creates temperatures of 200–300°C, the treatment is painful and requires some type of anesthesia stronger than an eutectic mixture of local anesthetics (2.5% lidocaine and 2.5% prilocaine emulsion in an oil-in-water base). Therefore, most clinicians feel that for the treatment of viral infections, this type of laser may be considered too invasive (Table 12.2). The most commonly used laser though is the FPDL, which emits light in the yellow-orange part of the visible light spectrum at 585 or 595 nm (Kauvar ANB). When turned against skin, this light is best absorbed by hemoglobin and oxyhemoglobin and is therefore used for the treatment of vascular lesions. With very short pulses (0.45 ms) purpura develops within minutes in the treated areas and needs 10–14 days to resolve as macrophages digest damaged material and blood residua. The yellow-orange light of this particular laser is designed to destroy superficial blood vessels.

384  Lasers in Dermatological Practice Table 12.2 Use of PDL lasers in viral disorders Molluscum contagiosum Dose Pulse duration No. of session

6–7 J/cm2 0.45 ms 1-2

Common warts Dose Pulse duration No. of session

8–12 J/cm2 0.45–1.5 ms 1–8

Genital warts Dose Pulse duration No. of session

6–7 J/cm2 0.45 ms 1–5

In viral warts the concept is to destroy the warts’ energy supply and supposedly induce their regress, although a number of studies using the FPDL and the same treatment parameters offer controversial results (Kopera D). Other than transient purpura, side effects from FPDL treatment of viral infections of the skin, when 0.45-ms pulses are used, are rare. They include postlesional hyperpigmentation, blistering, and sometimes scarring. Treatment for molluscum contagiosum must be individualized. Some treatments may be painful and would not be the first choice for children. Other treatments are not painful but require diligence over a long period of time. Sometimes, the best treatment is reassurance that the lesions are selflimited. Most would prefer curettage, cryosurgery, toxic or irritating topical agents (e.g. cantharidin, fluorouracil (5-FU), tretinoin, adapalene, salicylic acid), and immunomodulating topical imiquimod. Lasers in our view are a rapid method of therapy for molluscum. Apart from the CO2 laser, the flashlamp-pumped pulsed dye laser (FPDL) can be used. This author has treated numerous cases of molluscun contagiosum and it provides a rapid, fast method of treatment, with a mode of action that combines the best of extirpation and TCA/KOH, which is more cumbersome. Also the high temperature can effectively kill the virus. A single spot mode in a dose of 0.5–2 W, with a pulse duration 10 ms is sufficient.

Inflammatory Disorders Angiolymphoid Hyperplasia with Eosinophilia (ALHE) The treatment of ALHE is known to be difficult. Intralesional corticosteroids, surgical excision, and lasers are the most frequently used therapies, although none of them is uniformly effective in all cases. Other options reviewed in the literature are topical or oral corticosteroids, cryotherapy, oral retinoids, imiquimod, tacrolimus, bleomycin, and INFA-2a.

Miscellaneous Laser Responsive Disorders  385

Laser Laser therapy can be a useful tool, especially for challenging locations in which surgery cannot be performed. The most frequently used lasers to treat ALHE are those targeting oxyhemoglobin. The use of the argon laser (484–514 nm) was first reported in 1988 but its long pulse duration lead to nonselective damage and scarring. There are several reports about the use of pulsed dye lasers (PDLs) for ALHE; most of them are single case reports in which complete remission has been observed. Longer wavelength PDL (595 nm) seems to be slightly more effective because it enables deeper tissue penetration (around 2.5 mm). The common setting used are 585 nm, 7–10 mm, (5–7.5 J/cm2), 0.45 ms (Lertzman BH). But it must be appreciated that the results may require up to 7 sessions and are not complete except while using the 595 nm (Angel CA). Other lasers used include (Nd:YAG) laser has been reported, using a 6-mm round spot size with two pulses of 7 ms duration with a 20-ms interpulse delay and a fluence of 100–150 J/cm2. A copper vapor laser (CVL) was used for the treatment of ALHE in one patient. CVLs emit yellow light (similar to PDLs) of 578 nm. The pulse duration is 20 ms, with a pulse repetition rate of 15,000 cycles. Because the carbon dioxide (CO2) laser is an ablative laser that targets water, it is less selective than vascular lasers. But we prefer this as it has the advantage of ablation with coagulation and is immeasurably cheaper than PDL and millisecond pulsed Nd:YAG lasers (Kaur T). Though there are no reports of the Er:YAG as it has a poor cogulative profile a dual mode Er:YAG may be used.

Darier Disease This genetic condition has been treated by lasers, though chances of recurrence are there unless post-therapy histological confirmation can be done.

Lasers Used The carbon dioxide laser was successfully used to destroy recalcitrant plaques in two patients with Darier disease by McElroy et al. with significant improvement and recurrence in only one treatment site. The same laser was used by Minsue Chen et al. to treat a patient with lesions involving 40% of total body area. The authors used a 3-mm spot and energies ranging from 10 to 40 W in two passes with tumescent local anesthesia, without recurrence at 2 years of follow-up. Nevertheless, the risk of scarring with a carbon dioxide laser increases with the depth of treatment and the thermal damage. Beier et al. treated two patients with an erbium Er:YAG laser (2,940 nm) under local anesthesia with the painting technique and with an overlap

386  Lasers in Dermatological Practice

of 30%. The treatment endpoint was the exposure of the papillary dermis including a margin of adjacent normal skin, using up to seven stacked pulses, a spot size of 1.6 mm and fluences of 5–8.5 J/cm2. No recurrences and/or scarring were observed in the two patients in a follow-up of 20 months. Both patients had remission of the pruritus; post-treatment hypopigmentation was observed in the cubital and popliteal area of one patient and a few spots with the other patient. Post-treatment biopsies showed no signs of Darier´s disease in both patients. It is this author’s view that a combination of Er:YAG and CO2 is a better option as the Er:YAG has a predictable depth and when the end point of ablation is achieved a pass of CO2 can enable adequate coagulation.

Dermatomyositis There have been some reports of poikilodermatous erythema and telangiectasias of DM treated with pulsed dye lasers and argon lasers, with good response (Yanagi T). Lasers have also been used successfully to treat other connective tissue diseases (Brauer 2014).

Eczema In 2008, (Syed S) reported a pilot study showed that PDL treatment improves localized areas of chronic eczema. Twelve children with localized chronic eczema were treated with PDL (595 nm). After 2 and 6 weeks, a significant decrease in eczema severity score was seen for the PDL-treated areas compared with the control areas. Treatment was well tolerated. This may suggest that dermal vasculature plays an important role in chronic eczema or that PDL treatment may have an effect on cutaneous immunological activation (Woo PN).

Elastosis Perforans Serpiginosa Treatment with pulsed carbon dioxide and Er:YAG laser techniques may have been modestly helpful in patients with idiopathic EPS (Vestey JP). The pulsed dye laser has appeared to be beneficial in one reported case of EPS in a patient with Down syndrome.

Granuloma Annulare (GA) In 1988, a carbon dioxide laser was used with good results to treat GA. There are reports of the use of PDL where the lesion was treated with three times, initially and at months 5 and 13. After the first session of treatment, significant flattening and reduction of erythema were evident. After the second and third treatments, further improvment was observed and long-term remission was achieved (Sniezek PJ).

Miscellaneous Laser Responsive Disorders  387

In 2008, Karsai et al. (Karsai S) reported a patient with disseminated GA who was treated with fractional photothermolysis using a 1,440-nm Nd:YAG laser. A complete remission was achieved after two treatment sessions. A recent report describes the use of excimer laser (Bronfenbrener R), though it is the author’s opinion that the results of photochemoterapy are better with almost 50% clearing on the PUVA with a 79% remission rate (Browne F).

Granuloma Faciale (GF) A variety of surgical procedures may be used in the management of GF: surgical excision, dermabrasion, electrosurgery, cryotherapy, and different types of lasers. Argon laser use was first reported in 1988, resulting in resolution of the clinical and microscopic abnormalities. The laser most frequently used to treat GF has been the pulsed dye laser.

Hailey-Hailey Disease Dermabrasion is also an option for refractory lesions, with clearance rates as high as 83% but with hypertrophic scarring being observed. Similar to the patients with Darier’s disease, the use of the carbon dioxide laser to vaporize the lesions has been described by several authors (Kartamaa M), with the treatment endpoint being skin destruction reaching the follicular infundibulum while sparing the adnexal glands to avoid hypertrophic scarring. Kartamaa et al. used a continuous carbon dioxide laser to treat six patients with symmetrical lesions, leaving one side as an untreated controls. There was improvement on the treatment side in five patients, with hypertrophic scarring occurring in the axilar area of the other patient. Christian et al. reported one patient with refractory axillary lesions treated with three passes of a carbon dioxide laser using a fluence of 28 J/cm2; focal recurrences were managed with a short dwell carbon dioxide laser with a fluence of 15 J/cm2. Complete resolution was observed in only one side. Beier et al. treated two patients with an Er:YAG 2,940-nm laser under local anesthesia with the painting technique. These patients had axillary and groin lesions and the treatment parameters were as follows: 0.35 ms pulse duration, up to 7 stacked pulses, 5 mm spot size, and 5–8.5 J/cm2 fluence. Complete remission was observed in one patient at 1 year of follow-up; in the other patient lesion recurrence occurred at the edges and adjacent areas, which were managed with an additional treatment.

Lichen Sclerosus The first line of therapy is potent topical corticosteroids, such as clotebatosol propionate for at least 3 months, combined with emolliens.

388  Lasers in Dermatological Practice

Recalcitrant lesions can be treated with a carbon dioxide laser, as published by Peterson et al. The carbon dioxide laser is an ablative option for this pathology with a retrospective study of 50 patients showing that 80% of the patients were disease free at a median follow-up of 14 years (Windahl). A simple method is to use the pulsed mode or a repeat mode (3–4 W; 0.20 S) in a defocused beam and vaporize the macroscopically altered area of the glans penis. If there is a phimosis that can be also treated simultaneously. The PDT has been tried in 12 females with vulvar lichen sclerosus where a dose of 30–70 mW/cm2 was used with a wavelength of 635 nm. Treatment was well tolerated by eight patients and a marked improvement in pruritus was observed in 10 women, which was maintained for a mean of 6 months. It must be remembered that surgical treatment by  circumcision  can be curative, if the disease is treated early when still localized. Once progression to urethral involvement has occurred, treatment is much more difficult and lasers should be reserved for the early stage before meatal stenosis has occurred (Stewart L).

Lupus Erythematosus Though laser therapy offers novel and often effective treatment for recalcitrant cutaneous conditions in lupus erythematosus (LE) scleroderma, sarcoidosis, and dermatomyositis the limited number of reports, with outdated technologies and techniques makes it difficult to recommend this as a first line therapy for CTD (Brauer JA). The PDL is used in several vascular disorders, such as rosacea telangiectasias or port wine stains. The wavelengths of 585 or 595 nm are selectively absorbed by oxyhemoglobin and allow a selective destruction of the vessel walls. The rationale for the therapeutic success of PDL in LE is the growing evidence that endothelial cells play a major role in the inflammatory process and systemic manifestations in LE. The targeting of endothelial cells in rheumatic diseases is now an important field in the development of new drugs (Szekanecz Z), and even classic drugs used in the treatment of LE, such as chloroquine, have been shown to reduce skin lesions from LE partially through inhibition of angiogenesis. Published series of patients with LE lesions treated with a PDL (Raulin C) showed significant improvement of skin lesions, even in those patients with the systemic form of the disease. The older series used a PDL with a wavelength of 585 nm, achieving a clearance rate of 70% in nine patients. Another application for lasers in the treatment of LE is the atrophic scars, especially in DLE because this subtype frequently causes disfiguring and cribriform scars. The carbon dioxide laser in continuous wave mode has been used though this author favors the use of the Erbium:YAG laser, due to its measured dose depth response and excellent healing after ablation.

Miscellaneous Laser Responsive Disorders  389

But it must be remembered that LE may be aggravated by UV light though there are no published reports of such an aggravation due to PDL, CO2, or erbium:YAG lasers.

Necrobiosis Lipoidica In 1999, Currie et al. described a case report of necrobiosis lipoidica (NL) treated with a PDL. At low fluences, minimal therapeutic effect was achieved, and at higher fluences skin breakdown occurred, so they concluded that caution is required when attempting to treat NL with a laser. Other therapies tried include photodynamic therapy (De Giorgi V).

Nodular Amyloidosis A patient with a large scalp lesion of nodular primary LCA was treated with a CO2 laser with excellent cosmetic results and minimal morbidity (Truhan AP). In 1999, a case report of multiple nodules treated with a PDL was described, with clinical improvement in the color, size, and friability of nodules maintained for 6 months (Alster TS). Histologic examination revealed decreased inflammation and improvement in dermal collagen after laser irradiation. There are certain important issues to appreciate before using lasers for this condition (Lesiak A). Firstly, the pathology is deep and the amyloid is admixed with a proliferative vasculature with the result that most ablative procedures encounter bleeding that is an issue while treating this condition with lasers (Hamzavi I). Though a report of fractional ablative laser has been published (Anitha B), the concomitant use of a topical steroid salicylic acid ointment means that probably the fractional lasers helped to increase the transcutaneous penetration of the steroid than acted alone.

Sarcoidosis Laser therapy has been used mainly for lupus pernio, which is the most characteristic lesion of cutaneous sarcoidosis. It has a predilection for acral sites, most commonly the nose. The lesions are usually violaceous plaques or nodules that can be disfiguring and can cause significant psychological morbidity.

Lasers Used Pulsed dye laser (PDL) was first used by Goodman et al. where a 75% improve­ ment after two treatments was seen, but recurrence was observed after 6 months. Cliff et al. confirmed the PDL’s effectiveness to clear lupus pernio clinically and histologically, with no recurrence after 2 months.

390  Lasers in Dermatological Practice

The carbon dioxide laser remodeling and healing by secondary intention have also been performed for lupus pernio. Six cases have been reported (O’Donoghue NB) with satisfactory aesthetic results and no recurrence in most cases. Some use intralesional triamcinolone acetonide after laser therapy (Stack Jr BC). In addition, the 532-nm frequency-doubled Nd: YAG laser has been used to treat lupus pernio with a complete remission after a 3-year follow-up (Ekback M). Scar sarcoidosis is characterized by erythema, infiltration, and progressive induration of a pre-existing scar. It can resemble hypertrophic scars or keloids. Anecdotal use of a Q-switched ruby laser lead to a complete clearance of scar sarcoidosis lesions (Grema H). Successful treatment of this condition was also reported using a 595-nm PDL. No recurrence was observed after 1 year of follow-up. Laser treatment seems to be effective for isolated cases of cutaneous sarcoidosis. Nevertheless, only few cases have been reported so far. (Brauer JA).

Conclusion There are two issues with the use of lasers. Firstly in most cases the followup period has been short for a disease like sarcoidosis where recurrences have been seen even after years of steroid therapy. Secondly there are cases of aggravation of sarcoidosis with PDL therapy and CO2 laser. Thus lasers are not to be used as a prefential treatment in sarcoidosis (Kormeili T)

Psoriasis The benefits of using the 308 nm excimer laser for psoriasis are wellestablished and it has been shown that the psoriatic lesions treated with the excimer laser cleared with fewer treatments than narrow band UVB therapy. Though a summary of the indications and advantages are given below, it is this author’s opinion that PUVA/sol is a reasonably effective option for psoriasis, with a more pronounced immunomodulatory effect than excimer laser.

Indications ¾¾ Localized plaques that have not responded to medical therapy ¾¾ Mild to moderate psoriasis ¾¾ Type II–IV skin with limited disease to the scalp or flexural areas.

Advantages ¾¾ It spares the uninvolved skin from UV exposure ¾¾ Remissions for up to 2 years have been seen in some patients

Miscellaneous Laser Responsive Disorders  391

¾¾ Laser therapy demonstrated efficacy at lower cumulative doses when compared to conventional light therapy ¾¾ Used for psoriatic lesions that occurs in the groin and axilla (inverse psoriasis) and scalp ¾¾ It can be used in all skin types.

Summary The ultraviolet B (UVB) phototherapy is an effective treatment modality for psoriasis. For patients with localized plaque-type lesions, 308-nm excimer laser phototherapy offers rapidly delivered, targeted, high UVB doses, while sparing adjacent healthy skin. A study by Mudigonda T compared the advantages and disadvantages of the 308-nm xenon chloride (XeCI) UVB excimer laser with nontargeted broadband UVB (BB-UVB), narrowband UVB (NB-UVB), and psoralen plus UVA (PUVA) phototherapies. Three prospective nonrandomized studies compared NB-UVB with excimer laser phototherapy. No head-to-head studies were found for BBUVB or PUVA compared to excimer laser. Both the 308-nm excimer laser and nontargeted phototherapies were found to effectively clear localized psoriasis. Although it is proposed that excimer laser exclusively treats diseased skin with better response rates, split-body trials revealed no differences. Longterm studies are necessary to compare the effects of high-dose excimer laser regimens with nontargeted phototherapies. Interestingly PUVA has not been compared with excimer laser and it is quite likely that due to the more profound immunomodulatory effect and depth of penetration, PUVA is probably superior in terms of efficacy and relapse rates.

Bibliography 1. Alster TS, Manaloto RM. Nodular amyloidosis treated with a pulsed dye laser. Dermatol Surg. 1999;25:133-5. 2. Angel CA, Lewis AT, Griffin T, Levy EJ, Benedetto AV. Angiolymphoid hyperplasia successfully treated with an ultralong pulsed dye laser. Dermatol Surg. 2005;31:713-6. 3. Anitha B, Mysore V. Lichen amyloidosis: novel treatment with fractional ablative 2,940 nm erbium: YAG laser treatment. J Cutan Aesthet Surg. 2012;5(2):141-3. 4. Beier C, Kaufmann R. Efficacy of erbium:YAG laser abla-tion in Darier disease and Hailey-Hailey disease. Arch Dermatol. 1999;135:423-7. 5. Brauer JA, Gordon Spratt EA, Geronemus RG. Laser therapy in the treatment ofconnective tissue diseases: a review. Dermatol Surg. 2014;40(1):1-13. 6. Bronfenbrener R,  Ragi J,  Milgraum S. Granuloma annulare  treated with excimer laser. J Clin Aesthet Dermatol. 2012;5(11):43-5. 7. Browne F, Turner D, Goulden V. Psoralen and ultraviolet A in the treatment of granuloma annulare. Photodermatol Photoimmunol Photomed. 2011;27(2):81-4.

392  Lasers in Dermatological Practice 8. Christian MM, Moy RL. Treatment of Hailey-Hailey disease (or benign familial pemphigus) using short pulsed and short dwell time carbon dioxide lasers. Dermatol Surg. 1999;25:661-3. 9. Cliff S, Felix RH, Singh L, Harland CC. The successful treatment of lupus pernio with the flashlamp pulsed dye laser. J Cutan Laser Ther. 1999;1:49-52. 10. Currie CL, Monk BE. Pulsed dye laser treatment of necrobiosis lipoidica: report of a case. J Cutan Laser Ther. 1999;1:239-41. 11. De Giorgi V, Buggiani G, Rossi R, Sestini S, Grazzini M, Lotti T. Successful topical photodynamic treatment of refractory necrobiosis lipoidica. Photodermatol Photoimmunol Photomed. 2008;24:332-3. 12. Dmovsek-Olup B, Vedlin B. Use of the Er:YAG laser for benign skin disorders. Lasers Surg Med. 1997;21:13-9. 13. Ekback M, Molin L. Effective laser treatment in a case of lupus pernio. Acta Derm Venereol. 2005;85:521-2. 14. Fitzpatrick RE, Goldman MP, Ruiz-Esparza J. Clinical advantage of the CO2 laser superpulsed mode. Treatment of verruca vulgaris, seborrheic keratoses, lentigines, and actinic cheilitis. Dermatol Surg Oncol. 1994;20:449-56. 15. Goodman MM, Alpern K. Treatment of lupus pernio with the flashlamp pulsed dye laser. Lasers Surg Med. 1992;12:549-51. 16. Grema H, Greve B, Raulin C. Scar sarcoidosis—treatment with the Q-switched ruby laser. Lasers Surg Med. 2002;30:398-400. 17. Hamzavi I, Lui H. Excess tissue friability during CO2 laser vaporization of nodular amyloidosis. Dermatol Surg. 1999;25(9):726-8. 18. Kardorff B. Neurofibromatose Typ I (Morbus Recklinghausen): Kombinierte Erbium:YAG-Laser- und Exzisionstherapie von kutanen Neurofibromen. Derm. 1998;4:404-6. 19. Karsai S, Hammes S, Rütten A, Raulin C. Fractional photothermolysis for the treatment of granuloma annulare: a case report. Lasers Surg Med. 2008;40(5):319-22. 20. Kartamaa M, Reitamo S. Familial benign chronic pemphigus (Hailey-Hailey disease). Treatment with carbon dioxide laser vaporization. Arch Dermatol. 1992;128:646-8. 21. Kaur T, Sandhu K, Gupta S, Kanwar AJ, Kumar B. Treatment of angiolymphoid hyperplasia with eosinophilia with the carbon dioxide laser. J Dermatolog Treat. 2004;15:328-30. 22. Kauvar ANB, McDaniel DH, Geronemus RG. Pulsed dye laser treatment of warts. Arch Fam Med. 1995;4:1035-40. 23. Kopera D. Verrucae vulgares: flashlamp-pumped pulsed dye laser treatment in 134 patients. Int J Dermatol. 2003;42:905-8. 24. Kormeili T, Neel V, Moy RL. Cutaneous sarcoidosis at sites of previous lasersurgery. Cutis. 2004;73(1):53-5. 25. Lertzman BH, McMeekin T, Gaspari AA. Pulsed dye laser treatment of angiolymphoid hyperplasia with eosinophilia lesions. Arch Dermatol. 1997;133:920-1. 26. Lesiac A, Rakowski A, Brzezinska A, et al. Effective treatment of nodular amyloidosis with carbon dioxide laser. J Cutan Med Surg. 2012;16(5):372-4. 27. McElroy JA, Mehregan DA, Roenigk RK. Carbon dioxide laser vaporization of recalcitrant symptomatic plaques of Hailey-Hailey disease and Darier’s disease. J Am Acad Dermatol. 1990;23:893-7.

Miscellaneous Laser Responsive Disorders  393 28. Minsue Chen T, Wanitphakdeedecha R, Nguyen TH. Carbon dioxide laser ablation and adjunctive destruction for Darier-White disease (keratosis follicularis). Dermatol Surg. 2008;34:1431-4. 29. Mudigonda T, Dabade TS, West CE, Feldman SR. Therapeutic modalities for localized psoriasis: 308-nm UVB excimer laser versus nontargeted phototherapy. Cutis. 2012;90(3):149-54. 30. O’Donoghue NB, Barlow RJ. Laser remodelling of nodular nasal lupus pernio. Clin Exp Dermatol. 2006;31:27-9. 31. Peterson CM, Lane JE, Ratz JL. Successful carbon dioxide laser therapy for refractory anogenital lichen sclerosus. Dermatol Surg. 2004;30:1148-51. 32. Raulin C, Schmidt C, Hellwig S. Cutaneous lupus erythematosus-treatment with pulsed dye laser. Br J Dermatol. 1999;141:1046-50. 33. Sajben FP, Ross EV. The use of the 1.0 mm handpiece in high energy, pulsed CO2 laser destruction of facial adnexal tumors. Dermatol Surg. 1999;25:41-4. 34. Sniezek PJ, DeBloom JR 2nd, Arpey CJ. Treatment of granuloma annulare with the585 nm pulsed dye laser. Dermatol Surg. 2005;31(10):1370-3. 35. Stack Jr BC, Hall PJ, Goodman AL, Perez IR. CO2 laser excision of lupus pernio of the face. Am J Otolaryngol. 1996;17:260-3. 36. Stewart L, McCammon K, Metro M, Virasoro R. SIU/ICUD Consultation on Urethral Strictures: Anterior Urethra-Lichen Sclerosus. Urology. 2014;83(3Suppl):S27-30. 37. Syed S, Weibel L, Kennedy H, Harper JI. A pilot study showing pulsed-dye laser treatment improves localized areas of chronic atopic dermatitis. Clin Exp Dermatol. 2008;33:243-8. 38. Sysa-Jedrzejowska A, Narbutt J. Effective treatment of nodular amyloidosis withcarbon dioxide laser. J Cutan Med Surg. 2012;16(5):372-4. 39. Szekanecz Z, Koch AE. Vascular involvement in rheumatic diseases: ‘vascular rheumatology’. Arthritis Res Ther. 2008;10:224. 40. Truhan AP, Garden JM, Roenigk Jr HH. Nodular primary localized cutaneous amyloidosis: immunohistochemical evaluation and treatment with the carbon dioxide laser. J Am Acad Dermatol. 1986;14:1058-62. 41. Vestey JP, Tidman MJ, Mclaren KM. Primary nodular cutaneous amyloidosis– long-term follow-up and treatment. Clin Exp Dermatol. 1994;19:159-62. 42. Windahl T. Is carbon dioxide laser treatment of lichen sclerosus effective in the long run? Scand J Urol Nephrol. 2006;40:208-11. 43. Woo PN, Finch TM, Hindson C, Foulds IS. Nodular prurigo successfully treated with the pulsed dye laser. Br J Dermatol. 2000;143:215-6. 44. Yanagi T, Sawamura D, Shibaki A, Shimizu H. Treatment for poikilodermatous erythema of dermatomyositis with the pulsed dye laser. Br J Dermatol. 2005;153(4):862-4.

Pigmentary Disorders Vitiligo Among the various forms of therapy for vitiligo, phototherapy is an important intervention. Excimer laser and light system are basically a form of targeted

394  Lasers in Dermatological Practice

UVB therapy, which is an option for small areas recalcitrant to conventional therapy.

Lasers Used The 308-nm excimer laser and lamp have been used in dermatology since 1997. These devices emit a wavelength in the UVB spectrum. The monochromatic wavelength at 308 nm provides photobiological effects for those devices that are theoretically superior compared with NB-UVB, especially for their immunologic effects. In vitiligo, a more immediate requirement is the migration and the proliferation of melanocytes where there seems to be no advantage of the 308-nm and NB-UVB wavelengths (Casacci M et al). The 308-nm excimer lamp is not strictly monochromatic and the beam of light is not coherent and those systems are much less expensive than lasers. The data concerning the treatment of vitiligo with the 308-nm excimer lamps are much more limited compared with excimer lasers, but they seem to provide a comparable rate of repigmentation (Shi Q et al). The 632.8-nm helium–neon laser has also been tried for vitiligo, though the data at present is limited.

Advantages The fluences to be used are low and the immediate side effects are limited to erythema and rarely blisters (especially if sessions are repeated 3 times a week). Also these devices allow treatment of areas that are usually difficult to reach with UV cabins such as the folds, and they specifically target the affected depigmented patches, preventing hyperpigmentation of the surrounding skin.

Disadvantages Only relatively small surfaces can be treated and most authors propose the use of these devices for lesions affecting less than 10% of the total surface body area.

Results The clinical efficacy of the 308-nm excimer laser is well demonstrated. Overall, 20–30% of the treated patches reach a satisfactory aesthetic result, that is, a repigmentation of at least 75%. Those results appear superior to those usually obtained with NB-UVB phototherapy but direct comparison data between NB-UVB and 308-nm emitting devices are still very limited. A study that has been published is a important lesson for clinicians wishing to buy the excimer system in preference over NB-UVB. Verhaeghe E studied the efficacy of 308-nm MEL versus localized 311-nm NB-UVB in vitiligo patients. This prospective intrapatient placebo-controlled

Miscellaneous Laser Responsive Disorders  395

randomized trial found that while 20% of the lesions treated with NB-UVB achieved repigmentation scores above 50%, none of the lesions treated with MEL achieved a repigmentation higher than 50% after 24 sessions. Thus, localized 311-nm NB-UVB is more effective in the treatment of vitiligo and an unbiased view reinforces the fact that it is better than the 308-nm excimer lasers. In India, where PUVA is practiced, it is the author’s opinion in conjunction with a recent study (Singh S) that probably with the abundant sunlight and low risk of melanoma in our skin, the excimer laser cannot be universally recommended especially for the larger population that cannot afford this therapy.

Other Indications of Excimer Laser They include postresurfacing leukoderma, leukoderma after laser tattoo removal with a Q-switched neodymium:YAG laser, hypopigmented striae, halo nevus and nevus depigmentosus.

Conclusion Lasers for vitiligo reinforce certain principles for using lasers. Firstly, they should be superior to conventional therapies, secondly the results should be stable and long-term follow-up studies must be published. The safety profile is a recurring theme, that is probably relevant in FST(I-III) but in darker skin types this is not necessarily an issue. Predictably, some of the advantages with conventional phototherapy and PUVA are also seen with excimer lasers, like, the excellent results on the face, with more than three-fourths of patients reaching at least 75% repigmentation. But the system has not been and probably will not be able to overcome the known issues with conventional phototherapy namely; 1. Lack of response on the extremities and the bony prominences. 2. Lack of stability of response, which is impossible to predict as longterm results have not been reported. In fact, one study reported no repigmentation after 1 year of follow-up. A summary of the use of this system is provided in Box 12.1.

Box 12.1 Overview of excimer laser light in vitiligo Indication

Limited or localized lesions of vitiligo

Site (most to least responsive)

Face, scalp/neck, genitals, trunk, extremities, hands and feet, including bony prominences

Skin type

Fitzpatrick III or higher skin types respond the best

Size

Small lesions respond more quickly

396  Lasers in Dermatological Practice

The development of the 308-nm excimer lamp is more recent and is much cheaper and the results are comparable to excimer lasers. Le Duff F et al. performed a prospective trial comparing the 308-nm excimer laser and the 308-nm excimer lamp and confirmed that these two devices are equally effective in repigmenting vitiligo patches.

Lasers and Melanocyte Grafting Surgical approaches are recommended for segmental vitiligo or for localized vitiligo that has been stable for more than 3 years. It is also a useful method for congenital hypomelanosis, such as piebaldism, or for nevus depigmentosus. The preparation of the recipient bed before grafting requires a homogeneous epithelial removal. Both the CO2 lasers (Kahn) and more recently, the erbium:yttrium aluminum garnet (YAG) lasers (Pai GS) followed by epidermal skin grafts or epidermal suspension grafts have been used. Such a method has also been used in piebaldism (Guerra L). Recently, dermabrasion with erbium:YAG laser followed by fluorouracil applications before narrowband (NB) UVB therapy was compared to NB UVB alone in 50 patients with symmetrical patches of vitiligo (Anbar TS). A moderate to marked improvement was observed in 78.1% of the lesions treated with the combination protocol as compared with 23.4% of the lesions that have only received phototherapy. Pain and transient hyperpigmentation was reported in the combination group. Those results clearly need to be confirmed, but they suggest an interesting new approach for treating vitiligo. Our experience with this is restricted to the Er:YAG. This is set at a dose of 5–6 J/cm2 and multiple passes are made till pinpoint bleeding appears, which is the end point. A study is underway comparing this with conventional surgical grafting, thus this author cannot yet recommend it as a preferential method for recipient site preparation (Figs 12.2 and 12.3).

Lasers for Inducing Leukoderma Laser devices were first used for depigmenting the residual pigmented areas in generalized vitiligo. Permanent depigmentation is usually proposed for people older than 40 years and after detailed information is given to the patient. Monobenzylether of hydroquinone (MBEH) causes a permanent depigmentation of the skin that has been used for generalized vitiligo. Though some lasers have been used the evidence for their use and their efficacy is limited. A short, retrospective study suggests that a Q-switched ruby laser is as effective as MBEH (depigmentation was observed in 69% of the subjects with both kinds of treatments) (Njoo MD). Of interest, a repigmentation of treated areas was observed in 44% and 36% of the patients treated with lasers and MEBH, respectively. Thus, patients should be informed of the risk of repigmentation after both kinds of treatment.

Miscellaneous Laser Responsive Disorders  397

Fig. 12.2: Two passes have been given with the Er:YAG laser. Note the loss of epidermis and a faint erythema, which signifies the papillary dermis

Fig. 12.3: Pinpoint bleeding is the end point of the ablation

Isolated success has been reported in a patient with generalized vitiligo who was treated with a Q-switched ruby laser, with no repigmentation observed 1 year after the treatment (Kim YJ). More recently, a Q-switched alexandrite laser has shown its efficacy in the depigmentation of one patient. Again, no repigmentation was observed at follow-up after 1 year (Rao J). A study from India (Majid I) used the Q-switeced 532 nm but the concomitant use of MBEH with the laser can potentially influence the results. Thus, depigmenting lasers seem to be an attractive alternative to MEBH for depigmenting patients with generalized vitiligo but they should be reserved for limited surfaces and they should not be proposed if depigmentation involves less than 50% of the affected area. In all the cases, patients

398  Lasers in Dermatological Practice

have to be clearly informed of the potential risk of later repigmentation and photoprotection of the treated areas should be systematically prescribed. More importantly if the Q-switched Nd:YAG is used the 532 nm is used in preference to the 1,064 nm.

Bibliography 1. Anbar TS, Westerhof W, Abdel-Rahman AT, Ewis AA, El-Khayyat MA. Effect of one session of ER:YAG laser ablation plus topical 5-Fluorouracil on the outcome of short-term NB-UVB phototherapy in the treatment of non-segmental vitiligo: a left-right comparative study. Photodermatol Photoimmunol Photomed. 2008;24:322-9. 2. Casacci M, Thomas P, Pacifico A, Bonnevalle A, Paro Vidolin A, Leone G. Comparison between 308-nm monochromatic excimer light and narrowband UVB phototherapy (311–313 nm) in the treatment of vitiligo—a multicentre controlled study. J Eur Acad Dermatol Venereol. 2007;21:956-63. 3. Guerra L, Primavera G, Raskovic D, Pellegrini G, Golisano O, Bondanza S, et al. Permanent repigmentation of piebaldism by erbium:YAG laser and autologous cultured epidermis. Br J Dermatol. 2004;150:715-21. 4. Kahn AM, Ostad A, Moy RL. Grafting following short-pulse carbon dioxide laser de-epithelialization. Dermatol Surg. 1996;22:965-7; discussion 967-8. 5. Kim YJ, Chung BS, Choi KC. Depigmentation therapy with Q-switched ruby laser after tanning in vitiligo universalis. Dermatol Surg. 2001;27:969-70. 6. Le Duff F, Fontas E, Giacchero D, Sillard L, Lacour JP, Ortonne JP, Passeron T. 308nm excimer lamp vs. 308-nm excimer laser for treating vitiligo: a randomized study. Br J Dermatol. 2010;163(1):188-92. 7. Majid I, Imran S. Depigmentation therapy with Q-switched Nd: YAG laser in universal vitiligo. J Cutan Aesthet Surg. 2013;6(2):93-6. 8. Njoo MD, Vodegel RM, Westerhof W. Depigmentation therapy in vitiligo universalis with topical 4–methoxyphenol and the Q-switched ruby laser. J Am Acad Dermatol. 2000;42:760-9. 9. Pai GS, Vinod V, Joshi A. Efficacy of erbium YAG laser-assisted autologous epidermal grafting in vitiligo. J Eur Acad Dermatol Venereol. 2002;16:604-6. 10. Rao J, Fitzpatrick RE. Use of the Q-switched 755-nm alexandrite laser to treat recalcitrant pigment after depigmentation therapy for vitiligo. Dermatol Surg. 2004;30:1043-5. 11. Shi Q, Li K, Fu J, Wang Y, Ma C, Li Q, et al. Gao T. Comparison of the 308-nm excimer laser with the 308-nm excimer lamp in the treatment of vitiligo—a randomized bilateral comparison study. Photodermatol Photoimmunol Photomed. 2013;29(1):27-33. 12. Singh S, Khandpur S, Sharma VK, Ramam M. Comparison of efficacy and sideeffect profile of oral PUVA vs. oral PUVA sol in the treatment of vitiligo: a 36-week prospective study. J Eur Acad Dermatol Venereol. 2013;27(11):1344-51. 13. Verhaeghe E, Lodewick E, van Geel N, Lambert J. Intrapatient comparison of 308nm monochromatic excimer light and localized narrow-band UVB phototherapy in the treatment of vitiligo: a randomized controlled trial. Dermatology. 2011;223(4):343-8.

Miscellaneous Laser Responsive Disorders  399

Hair Disorders Though, lasers have been used for hair transplantation, we will largely focus on the direct effect of lasers on hair growth. Though lasers and light therapies for alopecia include 308 nm excimer laser, fractional photothermolysis, and UV phototherapy, we will largely focus on LLLT (Avci P). It has long been known that red or near-infrared laser light promotes tissue repair and regeneration and low-intensity light called low-level laser therapy (LLLT) stimulates cellular activity (Schindl A). After the discovery of lasers in the 1960s, there has been tremendous interest in using these laser devices to treat various medical conditions. The most commonly used devices have wave lengths in the range 500–1,100 nm (the so-called optical window of tissue) and they deliver fluences of 1–10 J/cm 2 with a power density of 3–90 mW/cm2. LLLT has shown beneficial effects for a variety of medical conditions such as wound healing, nerve regeneration, joint pain relief, stroke recovery, and the prevention and treatment of mucositis. Home-use LLLT devices that emit low power coherent monochromatic red light have been developed for various skin conditions, including hair growth.

Alopecia The pathogenesis of alopecia depends on the type of hair loss. The genetic hair loss, androgenetic alopecia is consequent to DHT, which binds to the nuclear androgen receptor, which regulates gene expression. Disruption of epithelial progenitor cell activation and cell proliferation due to abnormal androgen signaling forms the essential pathophysiological component of this condi­ tion which in turn leads to continuous miniaturization of sensitive terminal hair follicles, and their conversion to vellus hair follicles. Although the exact genes involved in hair loss are not clearly known, some of the proposed genes responsible for hair growth are desmoglein, activin, epidermal growth factor (EGF), fibroblast growth factor (FGF), lymphoid-enhancer factor-1 (LEF1), and sonic hedgehog. There are several other forms of hair loss such as alopecia areata (AA), telogen effluvium (TE), and chemotherapy-induced alopecia. AA is an autoimmune inflammatory condition, which presents with non-scarring alopecia. While the conventional methods of therapy include topical minoxidil, finasteride (males only), and surgical hair transplantation with LLLT having received FDA approval. The HairMax LaserComb1 was approved by the US Food and Drug Administration (FDA) and received 510 K clearance as a safe therapy for the treatment of male AGA in 2007 and female AGA in 2011 (Wikramanayake TC). The other FDA approved devices include Sunetics, Laser Hair Brush and Clinical unit, Revage 670 Laser (Chair unit) and Spencer Forrest X5 (Handheld) Hair Laser. Recently a diode laser the X5 HairLaser has

400  Lasers in Dermatological Practice

been used. Though a sham device failure and resultant missing data from the control group, are a negative aspect, the authors report a positive trend hair growth, due to the chronic use of X5 hairlaser device (Blum K).

Basic Science of LLLT There are a few mechanisms proposed for its action and are listed below. 1. Stimulates the mitochondrial transport chain 2. Enhances ATP production 3. Stimulates wound healing 4. Reduces inflammation, improves neurologic damage, such as with stroke improves musculoskeletal and joint pain. The extension of this form of therapy to alopecia has an interesting history. In the late 1960s, Endre Mester, a Hungarian physician, began a series of experiments on the carcinogenic potential of lasers by using a low-power ruby laser (694 nm) on mice. Mice were shaved as a part of the experimental protocol. To Mester’s surprise, the laser did not cause cancer but instead improved hair growth around the shaved region on the animal’s back. This was the first demonstration of “photobiostimulation” with LLLT, and it opened a new path in the field of medicine. This experimental fact was supported by a clinical phenomenon where an increase in hair density, color or coarseness or a combination of these occurs at or around sites treated for hair removal (Vlachos SP, Moreno-Arias G) and is known as “Paradoxical Hypertrichosis”, the incidence of which varies from 0.6% to 10%. A group of researchers also observed transformation of small vellus hairs into larger terminal hairs upon low fluence diode laser treatment and named this phenomenon “terminalization” of vellus hair follicles (Bernstein EF). Why this happens is yet unknown and has been explained by a sub­ therapeutic heat generation, which induces follicular stem cell proliferation and differentiation by increasing the level of heat shock proteins (HSPs) such as HSP27, which plays a role in regulation of cell growth and differentiation. Thus sub-therapeutic injury caused by the laser could also result in the release of certain factors, which could potentially induce follicular angiogenesis and affect the cell cycling. Thus, laser phototherapy is assumed to stimulate anagen re-entry in telogen hair follicles, prolong duration of anagen phase, increase rates of proliferation in active anagen hair follicles and to prevent premature catagen development.

Conclusion A list of studies is mentioned in the Table 12.3. The results of all the devices depend largely on the parameters used to assess them and long-term followup. However, more studies are needed to optimize treatment parameters

Miscellaneous Laser Responsive Disorders  401 Table 12.3 Clinical studies of LLLT in Alopecia Patients

Diagnosis

Device parameters and treatment regimen

Yamazaki et al., 2003

6 male and 9 female patients

Alopecia areata

Super LizerTM pulsed linear light, 600–1,600 nm, 1.8W, 3 minutes/ week or every other week

The patients received additional supplements and medications and were treated until vellus hair regrowth in at least 50% of the affected area LLLT only accelerates the process of hair regrowth in AA patients

Satino et al., 2003

28 male and 7 female patients

Androgenetic alopecia

HairMax LaserComb 655 nm, 5–10 minutes every other day, for 6 months

Hair tensile strength improved in the vertex area for males and temporal area for females. Hair count improved (for temporal area: 55% in women, 74% in men, in vertex area: 65% in women, 120% in men) with vertex area in males having the best outcome

Kim et al., 2007

24 male patients

Androgenetic alopecia

655 and 780 nm, once a day for 10 minutes, for 14 weeks

Leavitt et al., 2009

110 male patients

HairMax LaserComb, 3 times/week for 15 minutes, for 26 weeks

Significantly greater increase in mean terminal hair density compared to subjects in the sham device group

Contd...

402  Lasers in Dermatological Practice

Contd... Patients

Diagnosis

Device parameters and treatment regimen

Lanzafame et al., 2013

44 male patients

Androgenetic alopecia

Helmet (TOPHAT655) containing 21, 5 mW lasers and 30 LEDs, 655 nm, 67.3 J/cm2 25 minutes every other day, for 16 weeks

35% increase in hair growth among male AGA patients

Kim et al., 2013

40 patients

Helmet type LLLT device, 650 nm laser with 630 and 660 nm LEDs, 92.15 mW/cm2,47.90 J/cm2 18 minutes/day, for 24 weeks

LLLT increased hair count and shaft diameter, however, blinded global images did not support these observations

and determine long-term efficacy as well as safety of emerging LLLT technologies. Most studies investigating effects of LLLT on hair growth have used wavelengths that range from 635 to 650 nm, but as of today no study has compared the effect of near-infrared wavelengths such as 810 nm, which have deeper penetrating capacities, to red light. Moreover, further studies are required to compare efficacy of different light sources (continuous vs. pulsed) and methods of light delivery (laser versus LED). While lasers are largely safe, there are certain overbearing concerns that shroud the use of these devices. 1. There is still a paucity of peer-reviewed studies validating LLLT for hair loss. It is unclear why so few studies exist, given the positive anecdotal reports described above. 2. The treatment of alopecia has moved from the domain of dermatologists to quacks, beauticians, homeopath and so called “trichologists”. While we can appreciate the nuances of the etiology, this is lost on alternative practitioners and patients. Thus, a detailed evaluation and biopsy with its proper interpretation is needed where necessary. If LLLT is made a “home use” device, which it largely is, there will be situations where results will not be commiserate with the diagnosis. Who will protect consumers from buying expensive items that may not be applicable or aggressive enough for their type of hair loss? But as trained dermatologists we should be open to the use of such devices where other options have failed, so long as reproducible studies can demonstrate their safety and efficacy.

Miscellaneous Laser Responsive Disorders  403

Nail Disorders The use of lasers for nail disorders is the hot new indication though it is fraught with numerous issues. The lasers used are, millisecond lasers, diode laser, Q-switched lasers, PDT and UV light and recently, fractional lasers have (Lim EH).

Mode of Action of Lasers It has been shown that a temperature of at least 55oC for 5 minutes is required to kill dermatophytes in water suspension (Engelhardt-Zasada C). In vitro studies have shown growth impairment of nail clippings or cell culture media above 50°C when heated with a 1,064 or 980 nm laser systems (Paasch U). Conversely, other in vitro studies have shown no inhibition of fungal growth with Nd:YAG laser treatment of T. rubrum (Hees H). Interestingly, the germination of certain species of dermatophytes is accelerated at 40 degrees. This may suggest a stimulatory effect at subtherapeutic temperatures. The problem is that dermatophyte infections are comprised of both hyphae and spores of which spores can be more difficult to eradicate. Also at high temperatures there can be damage to normal collagen (>45 degrees) and skin necrosis can be seen at 50oC. If laser and light-based devices act through nonspecific bulk heating of dermatophytes, there is a high risk of heating and destroying surrounding normal tissue while attempting to eradicate dermatophytes. This would produce unacceptable side effects such as ulceration, dyspigmentation, and scar. Thus, selective photothermolysis of dermatophytes, while sparing surrounding skin structures, is preferable. But conversely, a study by Carney C et al. where a submillisecond 1,064 nm Nd:YAG laser (Laser Genesis, Cutera, Inc.) was used found that direct laser irradiation with the 1,064 nm laser of fungal colonies on the potato dextrose agar plate only peaked to temperatures of 40 degrees. Also the average percent of disease involvement was not reported by the authors, but could be calculated with the stated results to be about 33%. The improvement in percent involvement however, did not correlate to clinical or mycologic cure. Although, the in vitro study showed a fungicidal effect with heat, the results did not translate to clinical effectiveness given the degree of temperature and duration of heat required to obtain a fungicidal effect.

Laser Used Currently, all of the FDA cleared lasers for the treatment of onychomycosis are neodymium-doped yttrium-aluminum-garnet (Nd:YAG) lasers including: Pinpointe TM FootLaser TM (Nuvolase, Inc., Chico, CA), GenesisPlus TM (Cutera, Inc., Brisbane, CA), Q-Clear TM (Light Age, Inc., Somerset, NJ), CoolTouch VARIA TM (CoolTouch, Inc., Roseville, CA), and JOULE ClearSense TM (Sciton, Inc., Palo Alto, CA). But as has been discussed in chapter 13 regulatory

404  Lasers in Dermatological Practice

clearance of medical devices is based on substantial equivalence to a legally marketed pre-existing device rather than on the basis of clinical trials data. Therefore, one cannot infer efficacy from FDA clearance. A list of studies where lasers have been used is summarized in Table 12.4, though as discussed above we feel that the Q-switched laser is probably an ideal laser (Figs 12.4A and B) as it tends to optimize the target size of the hyphae than the millisecond lasers. The sessions are spaced from 2 weeks to 4 weeks intervals.

Future Melanin, present in T. rubrum and T. mentagrophytes, especially in microconidia, may be selectively targeted by using wavelengths absorbed by

Fig. 12.4A: A case of distal lateral onychomycosis

Fig. 12.4B: Use of Q-sw Nd:YAG laser for treating onychomycosis (12 J/cm2 : 2 Hz)

Miscellaneous Laser Responsive Disorders  405 Table 12.4 Laser used for onychomycosis Author

Laser Used

Type

Fluence (J/cm2)

Size (mm)

Pulse duration (ms)

Carney et al

Laser Genesis

Nd:YAG 1,064

16

5

0.3

Gupta et al.

Joule Clear Sense

Nd:YAG 1,064

13

Gupta et al.

Q-Clear

QswNd:YAG 1064 nm

14

Harris et al.

Pinpointe , Foot Laser

Nd:YAG 1,064

Landsman et al.

Noveon

Diode

Lim EH

Fractional CO2 Topical Antifungal cream

Moon SH

1,064-nm long-pulsed Nd:YAG

0.3 2.5–6

3–10 nanosecond

__ __ _ 870/930

204–424

15

5

6,5

0.3

Weiss et al.

GenesisPlus

Nd:YAG 1,064

16

5

300

Zhang et al.

Pinpointe , FootLaser

Nd:YAG 1,064

240–324

3

30

melanin for which the Q-switched 1,064 nm Nd:YAG is ideal. The effectiveness of the 1,064 nm laser was proposed to be a photothermolytic effect of laser light absorption by melanin found in the cell wall of T. rubrum. In addition to the selection of a melanin specific wavelength, the selection of a pulse duration that matches the thermal relaxation of the target is needed. The thermal relaxation time can be approximated to the square of the diameter of the target. The small size of the melanin particle (0.1 mm) requires the use of a pulse duration in the nanosecond range, such as that provided by a Q-switched laser. In addition, the fungal structure can be targeted by using pulse durations that match the thermal relaxation time of dermatophytes. The thermal relaxation time of hyphae (2–10 mm) is 0.004–0.1 milliseconds, macroconidia (4–50 mm) is 16 microseconds to 2.5 milliseconds, and microconidia (2–4 mm) is in the 0.004–0.016 milliseconds range. Thus, selective targeting of dermatophytes likely requires pulse durations in the nanosecond to very low millisecond range. Although, it may be possible to target fungus with selective photothermolysis, many questions remain. The effects of the nail plate on laser optics are unknown and need to be investigated. Further, is there enough melanin and xanthomegnin present in the fungus to be effectively targeted? Finally, are there other untapped target chromophores that would be more effective? Additional studies are needed to answer these questions.

406  Lasers in Dermatological Practice

The most important issue is that all studies have variable cure rates, end points, dosages and long-term data are not present. The mismatch between in vitro and in vivo findings is a recurring theme. The study by Hollmig ST is probably the first RCT where it has been proved that there is no significant mycological culture or clinical nail plate clearance with 1064nm neodymium:yttrium-aluminum-garnet  laser compared with control. This has to be kept in mind, though we feel that using the fractional laser as a topical delivery enhancing agent may be the most sensible method to be pursued at present.

Bibliography 1. Carney C, Cantrell W, Warner J, Elewski B. Treatment of onychomycosis using a submillisecond 1064-nm neodymium: yttrium-aluminum-garnet laser. J Am Acad Dermatol. 2013;69(4):578-82. 2. Engelhardt-Zasada C, Prochacki H. Influence of temperature on dermatophytes. Mycopathol Mycol Appl. 1972;48(4):297-301. 3. Gupta A, Simpson F. Device-based therapies for onychomycosis treatment. Skin Therapy Lett. 2012;17(9):4-9. 4. Gupta AK, Simpson FC. Medical devices for the treatment of onychomycosis. Dermatol Ther. 2012;25(6):574-81. 5. Harris D, McDowell B, Strisower J. Laser treatment for toenail fungus. Proc SPIE. 2009;7161(71610M):1-7. 6. Hees H, Raulin C, Baumler W. Laser treatment of onychomycosis: An in vitro pilot study. J Dtsch Dermatol Ges. 2012;10(12):913-8. 7. Hollmig ST, Rahman Z, Henderson MT, Rotatori RM, Gladstone H, Tang JY. Lack of efficacy with 1064-nm neodymium:yttrium-aluminum-garnet laser for the  treatment of onychomycosis: A randomized, controlled trial. J Am Acad Dermatol. 2014 Mar 15. pii: S0190-9622(14)00987-6. doi: 10.1016/j. jaad.2013.12.024. 8. Landsman AS, Robbins AH, Angelini PF, Wu CC, Cook J, Oster M, Bornstein ES. Treatment of mild, moderate, and severe onychomycosis using 870- and 930-nm light exposure. J Am Podiatr Med Assoc 2010;100(3):166-77. 9. Lim EH, Kim HR, Park YO, Lee Y, Seo YJ, Kim CD, et al. Toenail onychomycosis treated with a fractional carbon-dioxide laser and topical antifungal cream. J Am Acad Dermatol. 2014 Mar 18. pii: S0190-9622(14)01024-X.doi: 10.1016/j. jaad.2014.01.893. 10. Moon SH, Hur H, Oh YJ, Choi KH, Kim JE, Ko JY, Ro YS. Treatment of onychomycosis with a 1,064-nm long-pulsed Nd:YAG laser. J Cosmet Laser Ther. 2014. [Epub ahead of print] 11. Paasch U, Mock A, Grunewald S, Bodendorf MO, Kendler M, Seitz AT, et al. Antifungal efficacy of lasers against dermatophytes and yeasts in vitro. Int J Hyperthermia. 2013;29(6):544–50 12. Weiss D. 3 Month Clinical Results Using Sub-Millisecond 1064 nm Nd:YAG Laser for the Treatment of Onychomycosis. Hammonton, NJ: Weiss Foot and Ankle Center; 2011.

Miscellaneous Laser Responsive Disorders  407 13. Zhang RN, Wang DK, Zhuo FL, Duan XH, Zhang XY, Zhao JY. Long-pulse Nd: YAG 1064-nm laser treatment for onychomycosis. Chin Med J (Engl). 2012;125(18):3288-91.

Vascular Disorders Though this topic has been discussed previously a few indications are covered here.

Spider Hemangiomas This is characterized by a central dilated vessel. They can be treated with most vascular lasers. The laser used is a PDL or a high-powered 532-nm device. As there is a large dilated feeder vessel, these lesions seem to respond best to a 40-ms pulse duration with energies of 13–15 J/cm². Most IPLs, low-energy 532-nm lasers, and 980-nm diode devices can also be used. We use the ultrapulse CO2 to target the central feeding vessels with satisfactory results.

Angiokeratomas of Fordyce These are typically asymptomatic vascular lesions characterized by blue-tored papules with a scaly surface, most often located on the scrotum. These lesions are easily treated with both the pulsed dye laser and longpulsed Nd:YAG lasers, though we have found the pulsed CO2 an excellent option. The pulse duration should be at least 0.20 seconds if a repeat mode is used (1–2 W) to help coagulate the vessels. A defocused mode should be used.

Glomus Tumor Hereditary multiple glomus tumors constitute an autosomal dominant skin disease that is known to demonstrate cutaneous mosaicism typified by type 1 and 2 segmental arrangements. These lesions characteristically can be spontaneously painful. Pulsed dye laser treatment can be used to relieve pain but may not be curative.

Telangiectasias These represent dilated capillaries and post-capillary venules with thickened walls. They are superficial (200–250 mm deep) and have small cross-sections (200–500 mm in diameter). The ideal laser is PDL though the associated purpura is a concern. A useful setting is a longer pulse width in the 6–10 ms range utilizing pulse stacking where two to four pulses are “stacked” immediately one on top of the other

408  Lasers in Dermatological Practice

until vessel clearing is noted. Another setting used is a longer pulse width in the 20–40 ms range; fluences between 7 and 10 J/cm2 and spot sizes of 5–10 mm. End Point: Immediate coagulation/graying that quickly cleares is the desired endpoint. The IPLs have also been shown to be effective against telangiectasias and have a lower risk of inducing purpura and generally induce a mild erythema. Effective fluences range from 32 to 40 J/cm2 with pulse width of around 20 ms. These are useful for larger matted telangiectasias and the diffuse erythema associated with rosacea.

Venous Lakes The venous lakes are very common about the lips and other mucous areas. They are large vascular channels, which are often deeply situated and respond to most high-powered, long-pulse devices with pulse durations of 20–60 ms. Laser therapy is often effective and needs to be tailored to the depth of the target vessels. The lasers used include PDLs, 755-nm alexandrite lasers, longpulse Nd:YAG lasers, and the combined 595-nm/1,064-nm multiplex device. PDL is often effective for superficial venous lakes, but the longer wavelengths of diode (800–900 nm), alexandrite (755 nm), or Nd:YAG (1,064 nm) lasers are necessary for thicker or deeper lesions. Fluences of 80 J/cm2, pulse durations of 60 ms or longer, and 10–12 mm tips are often required, which puts the epidermis at risk of being thermally damaged. Appropriate cooling is therefore very important. The aim with a PDL is to produce mild purpura and edema. With diode and Nd:YAG lasers, the goal is reduction in lesion, thickness and clearance of the ectatic vessel. For the larger and deeper lesions an Nd:YAG laser with a spot size of 3 mm, pulse widths of 30–100 ms and fluences of up to 150 J/cm2 may be needed.

Wound Healing The use of lasers for wound healing can be divided into two types: 1. Lasers to augment the healing of acute wounds (e.g. tissue welding, tissue soldering). 2. Lasers for chronic wounds (e.g. low intensity laser devices).

Lasers for Acute Wounds The main techniques of laser-assisted wound closure of acute wounds are: simple tissue welding, tissue soldering, dye-enhanced tissue welding, and addition of growth factors. The potential advantages of laser-assisted tissue bonding over conventional methods include increased immediate wound strength, fluid-tight closure, decreased operative repair time, reduced

Miscellaneous Laser Responsive Disorders  409

probability of infection and bleeding, and improved cosmetic results. However, lasers have disadvantages such as their high cost, risk of dehiscence, risk of thermal damage, and inconsistency of results. The exact mechanism involved in laser-assisted wound closure is not completely understood. The heat produced by laser energy in the tissue causes collagen fibers to lose their triple helix structure and become fused, intertwined, swollen, and dissolved and thus lead to better wound healing.

Lasers for Chronic Wounds Different lasers for treating chronic wounds include helium-neon, galliumarsenide (GaAs), gallium-aluminum-arsenide (GaAlAs), Nd:YAG, carbon dioxide, ruby, krypton, and argon dye lasers. The exact mechanism of action of low intensity laser therapy is not known. Current hypotheses are: stimulation of Ca influx and mitosis rate, increased expression of Heat-Shock-Proteins (e.g. HSP70), increased expression of growth factors such as TGF-b, alteration of mitochondrial activity and increased ATP synthesis, augmented formation of mRNA and protein secretion, enhancement of fibroblast and keratinocyte proliferation and migration, angiogenesis, improvement of phagocytosis, and increased rate of transformation of fibroblasts into myofibroblasts.

Conclusion To better understand the role of low-intensity lasers in healing of chronic wounds, well-controlled studies that correlate cellular effects and biologic processes are needed. In the absence of such studies, the literature does not appear to support widespread use of lasers in wound healing at this time.

Malignant and PreMalignant Disorders Though an overview of some conditions is given below, the use of lasers cannot replace the role of oncological referral, which should follow histological confirmation and precede any surgical intervention. Though Mohs surgery is the ideal intervention in certain scenarios, lasers can be used. Updated guidelines can be accessed at http://www.nccn.org/. These guidelines suggest that for precancerous disorders skin directed therapies may be tried, including lasers, though they cannot match the results of Mohs surgery.

Zoon’s Balanitis The first goal of therapy is the promotion of good hygiene; circumcision is the most consistently effective treatment. Topical steroids, antimicrobials, and hormonotherapy have all showed inconsistent results. The carbon dioxide laser is an effective treatment for Zoon’s balanitis, especially if circumcision is not a feasible option, and, more recently, good

410  Lasers in Dermatological Practice

results with an erbium:YAG laser were reported (Albertini JG). The patient was treated with an erbium:YAG by Albertini et al. and showed no clinical or histological evidence of relapsing with complete re-epithelialization occurring one week after treatment, similar to the patient treated with a carbon dioxide laser by Baldwin and Geronimus. Nevertheless, in a series of 5 patients treated with a CO2 laser (Retamar RA) two patients relapsed after 1 or 3 years, with the third patient later developing lichen sclerosus.

Basal Cell Carcinoma/Squamous Cell Carcinoma For low risk NMSC, skin directed therapies can be used, including imiquimod 5%, RT, PDT and cryotherapy (NCCN guidelines version 2. 2014). Thus before laser therapy, one or more biopsies must always be taken to confirm the diagnoses histologically. The following laser procedures have been tried:

1. Ablative Lasers ( CO2 and Er:YAG) The limits of laser procedures are inherent in the depth of penetration of the lasers vis a vis the disorder that requires treatment. According to Horlock et al., treatment with the CO2 laser is advantageous especially for patients with histologically superficial BCC. In addition, the extent of the ablation increases with the practitioner’s clinical experience. In a study with 30 lesions (17 BCCs, 13 SCCs in situ), Humphreys et al. also found that superficial lesions responded very well to treatment with the CO2 laser. In this study, an energy density of 500 mJ/cm2 in two to three passes was used. With increasing thickness of the lesions, there was histologically minimal thermal damage to the underlying tissue, so that after completion of the laser treatment, residual tumor cells were still present.

2. Nd:YAG Because of its limited penetration of 4–7 mm, the Nd:YAG laser is particularly suitable for the treatment of smaller and flatter tumors.

3. PDT and Similar Approaches Photodynamic therapy (PDT) is becoming more widely used, especially in the treatment of superficial basaliomas and squamous cell carcinomas of up to 2 mm in depth. Although, this is an interesting and promising therapeutic approach, the lack of long-term data means that it should not yet be regarded as a routine procedure for nodular lesions.

Erythroplasia of Queyrat/ Bowen’s Disease The standard treatment is micrographically monitored excision, preceded in all cases without exception by a biopsy to confirm the diagnosis and

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determine the depth of penetration. Alternatives available are curettage, electro-desiccation, cryotherapy, topical application of—fluorouracil, imiquimod, PDT, and laser therapy. The pulsed CO2 laser is now generally used for the treatment of Bowen’s syndrome and erythroplasia of Queyrat. Numerous case reports of successful treatment are available (Del Losada JP, Greenbaum SS). Martinez-Gonzalez et al. describe a lasting success achieved in 85% of their cases after only one treatment session with the CO2 laser. In 8% of cases, there was a later recurrence. A total of 2% of patients did not respond to laser therapy. Vaïsse et al. also report similar results in Bowen’s syndrome in one study (eight patients, ten lesions). In a period of almost 3 years, there was a single recurrence of one lesion. A case report published by Wang et al. also describes a combined treatment with the Er:YAG laser followed by topical application of 5-fluorouracil in one patient. It is not certain whether this procedure will eventually be accepted as standard, because no long-term observations of patient populations are yet available that would allow extrapolation of the results to other patients. To keep the recurrence rate as low as possible, an adequate safety margin must also be created in the healthy tissue when a laser surgical technique is used. As seen in Figures 12.5 to 12.7, bleeding makes the use of Er:YAG impractical. Very close follow-up monitoring is necessary, as with all techniques, especially because complete removal of tumor complexes cannot be absolutely guaranteed and there are still no adequate long-term observations on recurrence rates available.

Fig. 12.5: A case of Erythroplasia of Queyrat

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Fig. 12.6: A spot is treated with pulsed CO2 (Repeat Mode, 4 W, 0.20 sec). Note the bleeding as the epidermis is ablated

Fig. 12.7: A few more passes are given till the elevated surface is ablated. A staged approach should be used for laser therapy of malignant tumor

Paget’s Disease Extramammary Paget’s disease is, by definition, an intraepithelial adeno­ carcinoma that occurs with particularly high frequency in the genitoanal region. There have been several reports of its treatment with the pulsed CO2 laser and the pulsed Nd:YAG laser. Louis-Sylvestre et al. described recurrence rates of up to 67% after a year after treatment with the pulsed CO2 laser; these rates can be reduced to 23% minimum by combining the laser therapy with extensive surgical excision. In a few cases it proved possible to achieve a disease-free state lasting up to 4.5 years with the combined treatment (Ewing TL).

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For some time, PDT has been used with increasing frequency as an alternative to the laser for treatment of Paget’s disease (Shieh S). As of this writing, however, there still have not been any studies about this disease in large patient populations. The application of laser systems to date has been based mostly on case reports. Because there also have been reports of ineffectual treatments with the CO2 laser, careful consideration must be given to whether laser treatment is indicated, and very close follow-up is an essential part of the therapy (Puppala S).

Parapsoriasis/Mycosis Fungoides Mycosis fungoides (MF) is a T-cell, non-Hodgkin lymphoma. Only in the early stages where systemic involvement is not marked, skin directed therapies are used. These include steroids, topical chemotherapy, RT, phototherapy, imiquimod and retinoids(NCCN Guideliens Version1.2014). Goldberg et al. had reported a successful treatment of palmoplantar lesion with the pulsed CO2 laser in 1997. During a follow-up period of 5 years, the patient remained free of recurrence. Excimer laser has been used both in MF and parapsoriasis but in the early stages of the disease. This type of laser is used because it is thought that, compared with total-body irradiation with UV light, the selective application of lasers makes it possible to protect healthy skin at the same time. Passeron et al. showed that complete healing of circumscribed plaques can be attained with a mean of 7–15 sessions and an average of 7 J energy applied per cm2. These results remained stable for a total of 3 months. Mori et al. also used the excimer laser in seven stage 1A lesions with complete lack of recurrence after 3–28 months. This was improved by Nicticó et al. who achieved a recurrence free interval of more than a year after treating ten lesions in the same stage; a cumulative energy dose of 6–12 J/cm2 was applied. Upjohn et al., in a study with 8 stage 1A or 1B patients, showed that after 20 treatment sessions with the excimer laser, there was complete clinical and histological remission in 37% of cases, which persisted for at least 30 months. In a further 37%, there was an initial clinical and histological remission. However, during the course of follow-up there was a recurrence. The PDT has also already been successfully applied in these conditions, although as of now there are no long-term data about recurrence rates. In summary, laser therapy can be a helpful complement to the treatment of MF, especially in its early stages. Long-term results and studies of large patient populations are not yet available.

Bibliography 1. Albertini JG, Holck DE, Farley MF. Zoon’s balanitis treated with Erbium:YAG laser ablation. Lasers Surg Med. 2002;30:123-6.

414  Lasers in Dermatological Practice 2. Baldwin HE, Geronemus RG. The treatment of Zoon’s balanitis with the carbon dioxide laser. J Dermatol Surg Oncol. 1989;15:491-4. 3. Del Losada JP, Ferré A, San Román B, et al. Erythroplasia of Queyrat with urethral involvement: treatment with carbon dioxide laser vaporization. Dermatol Surg. 2005;31:1454-7. 4. Ewing TL. Paget’s disease of the vulva treated by combined surgery and laser. Gynecol Oncol. 1991;43(2):137-40. 5. Greenbaum SS, Glogau R, Stegman SJ, et al. Carbon dioxide laser treatment of erythroplasia of Queyrat. J Dermatol Surg Oncol. 1989;15(7):747-50. 6. Horlock N, Grobbelaar AO, Gault DT. Can the carbon dioxide laser completely ablate basal cell carcinomas? A histological study. Br J Plast Surg. 2000;53(4): 286-93. 7. Humphreys TR, Malhotra R, Scharf MJ, et al. Treatment of superficial basal cell carcinoma and squamous cell carcinoma in situ with a high-energy pulsed carbon dioxide laser. Arch Dermatol. 1998;134(10):1247-52. 8. Louis-Sylvestre C, Haddad B, Paniel BJ. Paget’s disease of the vulva: results of different conservative treatments. Eur J Obstet Gynecol Reprod Biol. 2001;99(2):253-5. 9. Martinez-Gonzalez MC, Pozo JD, Paradela S, et al. Bowen’s disease treated by carbon dioxide laser. A series of 44 patients. J Dermatolog Treat. 2008;11:1-4. 10. Mori M, Campolmi P, Mavilia L, et al. Monochromatic excimer light (308 nm) in patch-stage IA mycosis fungoides. J Am Acad Dermatol. 2004;50(6):943-5. 11. Nisticó S, Costanzo A, Saraceno R, et al. Efficacy of monochromatic excimer laser radiation (308 nm) in the treatment of early stage mycosis fungoides. Br J Dermatol. 2004;151(4):877-9. 12. Passeron T, Angeli K, Cardot-Leccia N, et al. Treatment of mycosis fungoides by 308 nm excimer laser: a clinical and histological study in 10 patients. Ann Dermatol Venereol. 2007;134:225-31. 13. Puppala S. Failure of carbon dioxide laser treatment in three patients with penoscrotal extramammary Paget’s disease. BJU Int. 2001;88(9):986-7. 14. Retamar RA, Kien MC, Chouela EN. Zoon’s balanitis: presentation of 15 patients, five treated with a carbon dioxide laser. Int J Dermatol. 2003;42:305-7. 15. Shieh S, Dee AS, Cheney RT, et al. Photodynamic therapy for the treatment of extramammary Paget’s disease. Br J Dermatol. 2003;146(6):1000-5. 16. Upjohn E, Foley P, Lane P, et al. Long-term clearance of patch-stage mycosis fungoides with the 308-nm laser. Clin Exp Dermatol. 2007;32(2):168-71. 17. Vaïsse V, Clerici T, Fusade T. Bowen disease treated with scanned pulsed high energy CO2 laser. Follow-up of 6 cases. Ann Dermatol Venereol. 2001;128(11):1220-4. 18. Wang KH, Fang JY, Hu CH, et al. Erbium:YAG laser pretreatment accelerates the response of Bowen’s disease treated by topical 5-fluorouracil. Dermatol Surg. 2004;30(3):441-5.

Conclusion The data and experience given here is possibly a “birds-eye” view of the plethora of indications and lasers that can be used. But it is the experience

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of this author that most of the indications that have consistent response are while using the conventional ablative lasers. The use of excimer lasers in pigmentary disorder may be justifiable, but in pigmented skin, the result may not be different from conventional treatments (e.g. PUVA in vitiligo). As far as malignant cases are concerned, lasers do not find any mention in the NCCN guidelines (http://www.nccn.org/default.aspx) and should be used only in the premalignant conditions. The use of lasers in hair and nail disorders has received FDA approvals, but there is still a need for multiple, RCT, on these conditions with long-term follow-up with preferably comparison with conventional modes of therapy.

Chapter

13

How to Start a Laser Practice (Private Setup) Anil Ganjoo

Use of lasers, in dermatology, has been rapidly increasing. Over the last 4 to 5 decades, that lasers have been around, there have been rapid advances in the technology and therapeutic efficacy of lasers. Extensive research has given a better understanding of the laser tissue interaction and this has allowed us to expand the therapeutic options with lasers and has improved the clinical outcome. Lasers have now become the treatment of choice for a number of conditions that were thought to be virtually untreatable about 5 decades ago. Since their inception about 50 years ago, lasers have come a long way. From the initial use of ruby laser for almost every condition to highly precise laser for each condition we have progressed a lot. With the advances in technology have come the advances in the availability of large number of different types of systems and large numbers of dealers dealing in similar systems, which has made the laser scene very complex and confusing. Selecting the right system and the right dealer is of utmost importance for a good laser practice. We have been using lasers in India for the last about 15 years and this decade and a half experience has taught a lot of lessons. While working on our patients we have found that our kind of skins behaves differently than the western skins. Therefore we have developed our own parameters that suit our patients’ skins. We now know that if used judiciously lasers are wonderful but they have their shortcomings. When planning a laser set up, one should be well aware of the laser physics, which will help in selecting the system with the right parameters. To begin, the physician should know: ¾¾ His budget ¾¾ His patient profile ¾¾ His patient volume ¾¾ His patients’ paying capacity. The budget situation decides what kind of investment can be put in and therefore what kind of machines can be bought. Depending upon the type of patients one sees in practice, he can decide as to which system should be

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his first priority. One should be able to foresee what procedure would be in greatest demand in one’s practise. For example, if the physician has a lot of young and old hirsute women walking in then the first system that is bought should obviously be a hair reduction system, while if you get a lot of scars then a fractional resurfacing system should be your choice. Only those with a good volume of patients should plan to set up a laser practice as high turnover of patients is necessary for recovering the high cost of the machines. Last of all, the area that you are practicing in is very important as that determines whether the patients will be able to pay the high costs involved. One of the most common questions asked by the starters is whether to start with a platform with multiple functions or to go for a standalone machine. In practice, buying stand alone systems is always more beneficial as they are more effective than the combinations and also if a platform breaks down all your lasers will break down while if a standalone machine breaks down only that particular wavelength is gone.   While buying a new system one should look for: ¾¾ The best specifications. ¾¾ Whether that particular system is being used by other colleagues. ¾¾ The reliability of the dealer. ¾¾ The after sales record of the dealer.

System specifications Specifications of the machine are the most important deciding factor to pick up a system.   For hair reduction following systems are available in India: 1. LP Nd:YAG – 1064 nm 2. Diode – 810 nm 3. Alexandrite – 755 nm 4. IPL – 400–1200 nm 5. In motion technologies a. Diode b. IPL. Long pulse Nd:YAG is the safest due to the longest wavelength. Diode is slightly more efficacious but can produce side effects like burns and pigmentary disturbances, particularly in our kind of dark skins. IPL systems is the classic ‘jack of all trades masters of none’. They can do multiple jobs but their efficacy is not comparable to the standalone wavelengths. In general, the machine you buy should have a large spot size available as larger the spot size, leser is the scattering and deeper is the penetration. The system should have variable pulse width–10 to 100 milliseconds, which ensures targeting hairs of various thicknesses. Above all the machine should have good power and should be sturdy.

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The lasers used for pigmented lesions are the Q-switched lasers. These include: 1. Qs frequency doubled Nd:YAG laser – 532 nm 2. Qs ruby laser – 694 nm 3. Qs alexandrite laser – 755 nm 4. Qs Nd:YAG laser – 1,064 nm 5. IPL – 590–1,200 nm   In India, the most commonly used is the Qs Nd:YAG system 1. 1,064 nm 2. 532 nm. All Q-switched machines have pulse widths of < 10 nano secs. High end machines with variable spot sizes of 2/4/6/8 mm are desirable. The machine should have a good power, with maximum fluence of at least 12 J/cm2, using the smallest spot size. Considering the cost constraints, people often prefer to buy the cheaper machines. However, cheaper machines with a single spot size of 2 mm and maximum energy output of 500–600 mJ/cm2 are not recommended. IPL is not a very good option for pigmented lesions. Fractional lasers are the new wonder machines that are now used for an increasing number of indications, major one being resurfacing for scars and ageing skin. These are available as ablative and non-ablative versions and both are quite effective. The ablative CO2 fractional laser gives the fastest and the best results but has a long downtime. Superficial scars can be taken care of with Erbium:YAG 2,940 nm fractional. It is thus the author’s opinion that the results of nonablative fractional lasers, like Er:Glass 1540 nm, are not comparable to that of ablative lasers. While buying a CO2 fractional machine one should make sure that the power of the machine should be at least 30 watts to 40 watts, the pulse width should be 500 ms to 600 ms and the machine should have variable density of spots thus. Less density with high power can be used for deep scars, while more density with low power can be used for rejuvenation and textural improvement.

Dealer Reliability Before buying a system try to integrate the evidence-based literature and experience of your peers who have been using that particular system or who know about it. Literature based evidence is hard to find since most of the machines have different specifications. But if available, can be a big help and confidence building measure. Peer advice is easy to get. Try to get in touch with colleagues who have been using the same system for some time. They are the best people to guide you about the working of the machine and also about the reliability of the dealer. It is better to believe what the peers say than to listen to what the manufacturers or the dealers say. Reliability of the dealer is a huge concern. Checking the credentials of the supplier is as important as the specifications of the machine itself. One

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should do a thorough market survey with inputs from colleagues and market experts before putting faith in a particular dealer. The dealer should be of good repute, should have an expert team of engineers who can provide a good post sale service. The office of the dealer should preferably be in your city so that he can be easily approached. Execute a proper contract of purchase which should include all aspects of warranty. Make sure that the warranty clearly mentions the time of warranty and the parts covered under it. Sometimes the parts that really need to be covered are not covered under warranty. These include parts that are more likely to wear out soon like the flash lamp, the optic cable, the lenses and the mirrors. Keep your eyes open to the possibility of getting a refurbished machine instead of a new one. So ask for import details of the machine including the papers of point and date of entry into the country and check whether the serial number mentioned on the papers is the same as that of your machine. Be in touch with the parent company through emails to make sure that a new machine has been imported directly from the parent company. Once the machine has been procured, have a written agreement with the company mentioning: ¾¾ Likely breakdowns ¾¾ Warranty—parts covered ¾¾ Cost of components that usually breakdown ¾¾ AMC after the warranty is over ¾¾ Most AMCs do not cover the commonly required components like fiber, flash lamps, power supply, etc. Service contract may also serve the purpose. At times you need to send your machine to the parent company in Europe/US to get it repaired. So do a proper homework and assess the post-sales performance of the company whose machine you intend to buy ¾¾ Insuring your machine is a good idea ¾¾ Installing a UPS is very useful as it ensures – Uninterrupted power supply – Prevents damage due to voltage fluctuations. Also remember that maintenance is an expensive affair as spares are quite costly. Considering the high initial cost and the expensive maintenance, it is always better for a few colleagues to get together to set up laser practice. This shares the cost of buying and maintenance and also increases the patient pool and more the number of patients treated better the cost effectiveness.

Avoiding Common Mistakes The single most common mistake is to obtain every single device in the market, buy every single handpiece on the platform and to get the latest and the greatest. While it is always tempting to do so it can be a big mistake also. Patients are looking for results and good outcomes. Bad results can

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spoil the reputation of the physician very easily. So try to get time-tested and result-oriented machines rather than the latest and the most expensive. The second common mistake is not accounting for all costs (direct and indirect). True costing should include all the overheads like electricity, time, staff, breakdowns, etc. A business plan with real return on investment (ROI) should be chalked out for each machine. Do not rely on the manufacturer’s ROI plan. Instead ROI should be based on maturity of practice, size and type of practice and competition in the market.

Conclusion The field of lasers and light devices is undergoing a huge revolution. There are a large number of machines available in the market that makes decision making a very difficult exercise. It is imperative for the physician to approach the issue in a stepwise manner. This includes: 1. Evidence based review and discussion with peers on the specifications of a particular system. 2. Assessment of the reliability of the dealer/manufacturer. 3. Working out a proper contract on sale and post sale service including the warranty. 4. Working out the real “return on investment” on the product considering ones practice in volume and demography as also the market competition. Remember if procured carefully and used judiciously, lasers can be a big boon to the dermatology practice.

Further Reading Books 1. Carbon dioxide and erbium YAG lasers In: Goldman MP (Ed). Cutaneous and cosmetic laser surgery, 1st ed. USA: 2006. 2. Skin resurfacing with ablative lasers In. Goldman MP (ed). Cutaneous and cosmetic laser surgery, 1st Ed. USA: 2006.

Journals 1. Alster, Cut resurfacing with CO2 and erbium: yag laser. Plast Reconstr Surg. 1999;103:619-322 2. Alster TS: Clinical and histologic evaluation of 6 erbium: yag lasers for cutaneous resurfacing. Lasers surg med. 1999;24:87-92. 3. Jaisn ME: Achieving Er:YAG superior resurfacing results with the Er: yag lasers. Arch facial plastic surgery. 2002;4:262-6. 4. Tissue effects of the Er: yag laser with varying passes, energy, and pulse overlap. Lasers Surg Med, 1998;22(suppl10);70.

Chapter

14

How to Set up a Laser Clinic in a Public Funded Institution Kabir Sardana, Atul M Kochhar

Introduction Though a previous chapter covers the topic in a private set up, as some readers may be in Government aided colleges, a perspective of how to set up a laser center is being given below.

Why buy Lasers? A trivial question with far reaching implications. Laser has become a part of dermatological practice, but it is not justified to expend money on all sorts of lasers. It is the authors opinion, that three basic principles must be met before ordering a laser, presuming of course that trained personnel are there to run it. 1. Lasers with a purely cosmetic need (like hair removal) should not be bought in a medical college government set up. This is as firstly they are time-consuming procedures and secondly are so well researched that there is little need for further studies on it. Moreover, the number of hair removal procedures in private set up are so many that nothing new can emanate out of a medical college experience. Another issue is that the laser clinic tends to be overrun by such patients leaving little time or energy for anything else! Finding approvals to spend public money on them of course is another matter. 2. Lasers where a research into new therapies or aspects of laser physics are needed should be bought. This includes fractional lasers and possibly novel pigment specific lasers. 3. Lasers should be bought for conditions that have organic and cutaneous needs, like scars, benign tumors, tattoos, nevus of Ota,vascular conditions where the costing in private centers is prohibitively high. Conversely where the cost of machine is not so high, like a good pulsed CO2 lasers, is a sensible buy as this can tackle most tumors, though having used the Er:YAG for a long time an ideal situation would be to have both the ablative lasers.

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Which lasers to buy? We are detailing a list of lasers that could be bought. This is based on almost 8 years of running, buying and maintaining lasers at our institution. Every center tends to justify its purchases and it is possible that there may be differences of opinion, but as tendering (see below) goes through multiple committees, justifying laser buys is difficult, if the needs of the government and the patients are not matched. It is difficult to justify say a laser lipolysis or a RF machine in most medical colleges!

Ablative Lasers Though most centers buy the CO2, we would recommend that if possible this should be specified as a ultrapulse CO2 and possibly a Er:YAG, the latter of which is one of the safest lasers with a predictable depth dose equation. The newer modulated Er:YAG lasers are even safer and better. As a thumb rule for epidermal and most dermal disorders, the Er:YAG is ideal and for vascular and lymphatic tumors, the CO2 laser is ideal.

Pigment Specific The large number of pigmented disorders in Indian skin calls for special techniques and apparatus to treat them. For most epidermal disorders, any Qsw laser will suffice, though in our skin type the Nd:YAG is preferred. This comes in two forms, 1,064 and 532 nm which covers most disorders. For dermal disorders like nevus of Ota and tattoos, ideally a laser with variable spot size is useful. As not all tattoos will respond to the Nd:YAG, so if finances allow a ruby laser would be a useful addition! Though we can forewarn the reader that justifying it will be difficult in Indian skin types!

Vascular Laser Though the PDL is the ideal laser, it has three issues. Firstly the wavelength and pulse duration has to be optimized, secondly the results in PWS are good only if treated early and lastly the specifications have been set largely for western skin types. The added problem of the consumable (dye) makes it a costly endeavor. But as the cost of therapy, say for PWS is so high in practice, we feel that a government set up should have one, if finances allow!

Fractional Laser The laser system is used largely for acne scars and rejuvenation, though a multitude of other uses exist. The advantage of buying this is that usually two or more probes can be bought with a system that can cover a range of indications. If a platform is bought, an ablative and a pigment selective probe can also be bought subsequently, which would be easy to justify.

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But there is little in vivo difference between buying a Fr Er:YAG. Fr Er:Glass and Fr :CO2 though there may be in vitro differences, thus it is better to buy anyone fractional laser and optimize the settings! It is a “must” to insist on US FDA or CE approved laser (see below) with histological dose depth studies. The latter is useful to use the proper dosage to target the pathology.

Hair Removal Lasers We do not find sufficient reason to justify its use in government medical colleges as it has little use apart from hair removal. Though the IPL was touted as a multiple use laser, in our experience, it is a “jack of all trades, master of one “, the “one” being hair removal! Moreover, purely on a research point of view, the number of hair removal procedures done in private centers are so many that little can be added to the existing data. Except for certain procedures like hair removal for scalp grafts, there is little use of this system in a public funded set up.

Excimer Laser The cost of the system, the abundant sunlight in India, cheaper phototherapy units and focused area of impact make it of little use in disorders like psoriasis and vitiligo. Even if a local area is resolved, these being generalized systemic disorders, we cant justify this equipment in a government set up. We have detailed on this aspect in the Chapter 12.

Subsurface Lasers, RF, Laser Lipolysis, LLT These systems, no doubt useful, achieve subsurface tightening, marginal growth of hair and minor reductions in fat. None of these can be justified, specially as they are prohibitively costly! Interestingly though they are all FDA approved, thus not all FDA approved systems should be necessarily be bought in a public funded institution.

To Delegate or Not to Delegate? Energy based devices have rapidly become “delegated” procedures. It is advisable not to do this as they are costly equipments and most “passing” residents tend to “hone” their skills, sometimes based on little formal knowledge. Each laser has nuances and it is our experience that the life of the laser is directly proportional to the use and the latter is related a lot to the “misuse” of lasers. Also a dedicated day should be allotted to laser clinic to avoid misuse. At the end of the day, it is the department head on whom the problems will “lie on” if things go wrong. At that time, placing a blame on the concerned person will be an issue if all and sundry have had a “free” hand with lasers. We recommend a dedicated day, place and trained personnel to operate lasers.

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Laser Procurement In Government Institutions How to buy the right Laser with public funds? Laser treatment is the new buzz word for dermatology, is growing day by day while the side-effect profile is going down. Though a detailed discussion of procurement is beyond the scope of this book as laser purchases are expensive. An overview is given below: 1. Need assessment: a. Scope of services of the hospital— A primary or even a secondary level hospital does not need lasers and such a request is rarely entertained b. Free or paid services— Though not always the norm some institution charge a fee that helps to justify a purchase of what is largely believe to be a cosmetic need c. Cosmetic or therapeutic machine— This is probably the most important indicator. Thus it is impossible to justify a hair removal laser, though a IPL which has, at least in theory, multiple uses can be requisitioned. Taking it further, a hospital with a Nb:UVB unit should not ideally ask for a excimer laser as again it is difficult to justify it for largely the same indication as phototherapy d. Manpower/space requirements— The former is probably more important and thus it is better for a medical college where there are residents to assist the primary care providers, to have a laser unit, as then usually routine cases can be handled even if there is a paucity of staff e. Budget considerations. 2. Framing the specifications: This is probably one of the few things that can decide the future of the machine. We have detailed the steps for FDA approval and verification which can help the buyer to decide “worthiness” of the laser company: a. Discussion in the departmental scientific committee b. Formulation of generic specifications c. Discussion on minimum standards acceptable d. Consensus e. Optional accessories required. 3. Forwarding the proposal: a. Sample standard demand performa b. Signature of at least 3 consultants c. Adequate justification for the procurement. 4. Discussion with the hospital purchase committee/third party coordinator: To add a level of fairness (occasionally delays) an external expert is asked to vet the proposal. This helps to take care of any legal or financial issues that may arise:

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a. Scrutiny of proposal b. Comments on justification c. Is the purchase commensurate with the treatment services scope of the hospital? 5. Procurement process: This step is crucial to purchase and requires a deep understanding of procurement policies of the government. The listed points might seem bureaucratic but happen to serve the dual process of verification and validation. It is the authors opinion that these steps have to be accepted and negotiated to properly purchase a machine a. Understanding the GFR—Fundamentals of e-procurement b. The tender document c. Vetting the proposal—HOD, accounts, competent authority d. Terms and conditions including after sales service, AMC e. NIT f. Tender schedule g. Formation of committees h. Tender opening—Prequalification bid i. Technical bid j. Financial/price bid k. Negotiations (if any) l. Agreement to purchase m. Letter of credit n. Dispatch of machine o. Freight and delivery p. Installation q. Trials r. Commissioning of machine—SOP s. Installation certificate t. Release of balance payment u. AMC.

Regulatory Approvals This means appropriate FDA 510(k) approvals in the USA, PMA, Health Canada in Canada, TGA in Australia, Ministry of Health, Labor and Welfare (Kohseishou) in Japan, appropriate CE marking for medical devices in Europe, and so on. Beware of claims like ‘Approved by the FDA’, the latter of which usually simply means a letter from FDA recognizing that the system is a nonsignificant risk device (NSR) or minimal risk device (MSR). This is not an approval to market, but is simply a guide based on which the institutional review board (IRB) of a research center can classify the system when it does take part in a properly structured study.

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FDA 510(k) Clearances Section 510(k) of the Food, Drug and Cosmetic Act requires device manufacturers who must register, to notify FDA of their intent to market a medical device at least 90 days in advance. This is known as premarket notification—also called PMN or 510(k). This allows FDA to determine whether the device is equivalent to a device already placed into one of the three classification categories. Thus, “new” devices (not in commercial distribution prior to May 28, 1976) that have not been classified can be properly identified. Specifically, medical device manufacturers are required to submit a premarket notification if they intend to introduce a device into commercial distribution for the first time or reintroduce a device that will be significantly changed or modified to the extent that its safety or effectiveness could be affected. Such change or modification could relate to the design, material, chemical composition, energy source, manufacturing process, or intended use. A simple way of confirming this is by, one, asking the company for a letter from FDA (see Figure 14.1 sample letter). A second method, which is a “back up” method is depicted in Figure 14.2 and 14.3. For any individual spending money on a laser, it makes a lot of sense checking the clearance on the FDA site. Of course once you settle for a nonUS FDA machine then this approval does not matter. But it should be made clear that inappropriate use of a unapproved laser is a common litigation claim and at least a CE approval must be obtained (Fig. 14.4)!

Looking Beyond the Price Ask the following questions before just haggling the price, which though is important may not matter if the device does not deliver results. 1. Internal trials if any? 2. Published data if any? (see below) 3. Histological depth penetration studies for fractional lasers. 4. Dose intensity parameters for your skin type. 5. Follow-up studies if any? 6. Postmarketing and service team site and offices. Verify the numbers and address. 7. Import license and dealership registration 8. Proof of a “firsthand device”. Some lasers have been reused and sold! 9. Any legal issues, merger, acquisitions of the company 10. Any complications reported.

What Has Been Published on the System/Technology? There are various types of publication and though most believe or are made to believe that not all laser can have publications, but it is our opinion that

How to Set up a Laser Clinic in a Public Funded Institution  427

Contd...

428  Lasers in Dermatological Practice

Fig. 14.1: Sample letter of US FDA approval for a medical device

How to Set up a Laser Clinic in a Public Funded Institution  429

Fig. 14.2: Site of US FDA 510(K) approval. ‘Enter’ the approval number and click on ‘search’

Fig. 14.3: Site of US FDA 510(K) approval. The exact approval date and device is verified

investing in a machine with published studies has a lot more value, even though we admit that occasionally authors may have conflict of interests. What you are looking for here are papers by reputable authors published in the indexed and peer-reviewed literature, or at least in well-established and peer-reviewed journals (15 or more volumes). A list of such journals is given in the Appendix. A citation index is added to help further buttress the validity of data (See Appendix in the end of the book). An alternative source is appropriate chapters in books from reputable publishers. What you should not fall for are so-called ‘white papers’ which any manufacturer can produce to look like a genuine publication, or articles

430  Lasers in Dermatological Practice

Fig. 14.4: CE Approval letter for medical device

How to Set up a Laser Clinic in a Public Funded Institution  431

from the commercially-oriented medical press unless they are also in turn backed up by ‘real’ papers. In India, like in many parts of the world, such scientifically sounding ‘journals’ abound and are not listed for obvious reasons in the Bibliography! The most deceptive “ploy” is where the sales person gives a study on the technology, but of a different company! Make very sure that the articles offered by the manufacturer/salesperson are on their specific system and wavelength(s). There is a lot of difference between approved systems and a unapproved system and often the intensity, dose or even wavelength is not the same as in the published articles.

Conclusion Though the regulatory approvals and procedural systems involved are daunting, the take home message is simple, ask for validation, proof of effectiveness, regulatory approvals and published studies. Buying a machine on hearsay and exhortations of speakers in conferences is probably the most foolish method of buying lasers. More importantly as all such procedures are open to medicolegal scrutiny it is better to have the right device as the approvals are a useful method of buttressing claims of “good practices” in the court. The cost of litigations and damages can often negate the temporary gains that may ensue by buying an unapproved and cheaper device.

Chapter

15

Therapeutic Pearls in Lasers Ganesh S Pai, Pavithra S Bhat, Dharmendra Karn, Narendra Kamath, Anusha H Pai

In this age of information, ignorance is a choice. To be aware of more effective treatment and to make the best use of lasers, useful inputs from experienced hands are necessary. Photomodulation, photothermal and photobiochemical processes of non-ablative nature are safe to use by beginners. Photothermolysis is ablative in nature. The energy levels are much higher and there is selective photothermal destruction as in Qsw 532/1064 lasers and nonselective photothermal as in carbon dioxide and erbium lasers. Fractional photothermal as a concept involving microscopic patterns of thermal injury has led to great safety in ablative resurfacing of scars. The thermal relaxation time of pulse carbon dioxide laser heated tissue is about 0.8 ms. In effect for the CO2 laser wavelength, we must deliver the necessary 5 J/cm2 in at most a 0.8 ms pulse, preferably less, if we expect to minimize injury to the underlying tissue. When the UltraPulse mode is used (Fig. 15.1), the zone of ablation is deeper but the zone of thermal damage is narrow. In comparison when the continuous wave (Cw) is used, zone of ablation is small, but there is a wide zone of the thermal damage and increased char. In effect, the Cw mode is only useful for lesions on the surface of the skin (Fig. 15.2). It is clear from the Table 15.1 that the upper eyelid has thinnest epidermal structure of 25 µm. Thus great care has to be taken to reduce power to the tissue, in comparison to cheeks (Tables 15.2 and Fig. 15.2). The erbium laser has a much lower depth of ablation and thermal damage than CO2 lasers. They are thus much safe to use for superficial lesions. Because of its high water affinity, the erbium loses its efficacy to penetrate the dermis as it meets the fluid interface at the dermoepidermal junction. Thus, it is relatively ineffective for acne scars which are placed in the mid-dermis. Fractional carbon dioxide laser operates near tissue ablation levels but only up to the fourth pass. After that, the energy is diverted to bulk healing rather than ablating tissue. This damages adjacent normal tissue and there is a risk of necrosis, delayed healing and scarring.

Therapeutic Pearls in Lasers  433

Fig. 15.1: Comparison of fractional CO2 laser pulse widths ~1.0 ms

Fig. 15.2: Importance of pulse duration on tissue effect using the CO2 laser

ACNE SCARS While treating acne scars, it is important to use deep fractional ablation in the base of the scars and lesser energy to reduce the sharp edges at the shoulder of the scar. The safest lasers are those which emit high power, high energy and short pulses. Fractional CO2 lasers are an excellent tool for acne scars in young patients (Figs 15.3A and B) but in middle-aged patients (Figs 15.4A and B) with sagging

434  Lasers in Dermatological Practice Table 15.1 Variation in skin depth and density of adnexal structures Skin site

Epidermis (µm)

Papillary dermis (µm)

Reticular dermis (µm)

Hair follicles

Sebaceous glands

Sweat glands

Forehead

120

95

1700

Average

Average

Poor

Upper eyelid

25

40

437

Poor

Poor

Poor

Lower eyelid

40

45

412

Poor

Poor

Poor

Mid cheek

125

135

2100

Average

High

Poor

Lateral cheek

120

97

2000

Average

Average

Poor

Upper lip

131

110

2000

Average

High

Poor

Upper neck

115

115

1460

Poor

Poor

Poor

Mid neck

75

71

1407

Poor

Poor

Poor

Low neck/ decolletage

70

60

1200

Poor

Poor

Poor

Adapted from G Sasaki Journal of cosmetic and Laser Therapy. 2009;11:190-201

A

B

Figs 15.3A and B: Fractional CO2 laser treatment for acne scars in a young patient

Therapeutic Pearls in Lasers  435 Table 15.2 Comparison between the CO2 laser and Erb:YAG laser Parameter

CO2 laser

Erbium:YAG laser

Wavelength

10,600 nm

2,940 nm

Depth of ablation

20 mm

1 mm

Thermal damage

60–80 mm

5–15 mm

Ablation threshold

5 J/cm2

1.5 J/cm2

A

B

Figs 15.4A and B: Fractional CO2 laser treatment for acne scars in middle-aged patient

of mid face, the procedure is not useful and may in fact trigger melasma in susceptible patients. Routinely in all patients with PIH post-fractionated CO2 laser, a fractionated Qsw 1,064 nm can be used to hasten dispersal of pigment three weeks after the procedure. Chemical reconstruction of skin scars (CROSS) is a unique technique using application of high concentrations of trichloroacetic acid (TCA) on

436  Lasers in Dermatological Practice

atrophic scars, focally to induce inflammation followed by collagenization. This technique alone has shown reduction in the appearance of scars and cosmetic improvement. Our experience has shown that combination of CROSS technique followed by ablative fractional laser shows better and early outcome in the management of scars. The combination of TCA and fractional laser both have synergistic effect to induce neocollagenesis.

Keloids Treatment of keloids on bearded areas such as jawline with CO2 lasers is meant to debulk tissue. Hair removal with a diode laser removes a source of constant stimulation of keloids as well as the repeated nicks and cuts caused by a razor blade while shaving.

Epidermal Nevi Epidermal nevi can be ablated by CO2 laser in a fractionated mode; but may need three sessions at monthly intervals. After an ablative laser, the wound needs regular dressings with ointment-based antibiotics as desiccation of a wound delays healing, leaves crusts and causes scarring. (Figs 15.5 to 15.8). Patients with light eyes need more care as pigmentation is difficult to remove post-procedure.

PIGMENTED LESIONS Melanocytic Nevus While using a Qsw 1,064 nm laser for pigmented nevus, one must ensure that it is not a dysplastic nevus (DN). DN is a marker for increased melanosome risk. Its clinical characteristics are that it is greater than 5 mm in size, has flatness and has variable pigmentation and irregular outline. A biopsy report before attempting the laser is advisable. Plastic surgical removal is preferable to laser removal in case of dysplastic nevus. More details have been detailed in a previous chapter: (Laser Treatment of Common Pigmented Conditions).

Freckles Freckles on patients with fair skin and brown hair respond well to 532 nm wavelength, but relapse and constant extra sun protection is essential.

Tattoo While considering tattoo removal, it is important to understand that there is no single laser that can treat all tattoos.

Therapeutic Pearls in Lasers  437

Fig. 15.5: Prelaser photograph of a case for periorbital rejuvenation

Fig. 15.6: Postoperative crusting and erythema

Fig. 15.7: Scarring postoperative view showing sign of scarring

Fig. 15.8: Eventual healing with good textural improvement

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Amateur tattoos contain elemental carbon and professional tattoos contain organic dyes and metallic elements. Sometimes, patients with recent tattoos complain of itching and redness. Red tattoo pigments which contain mercuric sulfate and cadmium sulfide which is used in yellow tattoos and is associated with allergic reaction. Red and green colored tattoos are relatively resistant to Q-switched Nd:YAG-lasers than blue or black colored ones. For resistant tattoos a combination of ablative fractional laser followed by Q-switched laser increases the tattoo clearance, reduces blistering, shorten recovery and diminish treatment induced hypopigmentation. Ablative fractional resurfacing (AFR) may enhance tattoo clearance through several possible mechanisms. These include transepidermal elimination of the tattoo and the associated inflammatory and phagocytic reacation, which helps to enhance the removal of the tattoo pigment. A recent technique uses a combination of UltraPulse CO2 and Qsw Nd:YAG which helps to rapidly remove tattoos (Sardana K). Whereas, 1,064 nm Nd:YAG is the work horse for black ink and 532 nm for red pigment it is the Q-switched alexandrite 755 which is the gold standard to remove green tattoos. Paradoxical darkening can take place while using a 1064 nm Qsw laser as the ferric oxide is reduced to ferrous oxide which is black in color. Such tattoos can then only be removed by an ablative laser such as erbium or fractional CO2 laser. A detailed description of procedures and scenarios is given in the Chapter Laser Treatment of Tattoos.

HAIR REMOVAL LASER Patient selection should be done with caution for the best results. Patients with thick, dark, terminal hair are the ideal subjects. Patients with darker skin, lighter hair, co-existent endocrine disorders, irregular visit schedules, and damaged skin tend to need more sittings, and response will be unsatisfactory. Insist upon a patient having a stubble before the procedure as it helps in area demarcation, and also ensures intact roots—the melanin—rich target of the laser. Gray hair does not get cleared by laser, while light/blond hair demand more sittings or a higher dosing. Areas to be worked upon should be discussed before the procedure. If the procedure demands a shaping of the hairline edge like beard-line, request the patient to mark the area to be cleared before the procedure. Postpone the procedure in patients who have a recent history of retinoids usage, abrasive procedures, sun damage, chemical peels on the area, and any damage to the local skin. Immunocompromized patient should not be treated by lasers.

Therapeutic Pearls in Lasers  439

Procedure The area to be worked upon needs to be marked upon with a skin marker pencil—wash proof, colored eyeliner pencils. White markers are the ideal choice. Never use dark colors like black, purple, deep blue, as these may absorb the laser and cause a local burn. If the adjacent area is a hairy region (forehead), the hair edge is best covered with a tape to prevent singeing of the intact hair. The cool tip of the laser may be supplemented with use of refrigerated ultrasound gel caution needs to be observed in dark patients, and in naturally pigmented areas, dense hairy areas, adjacent to tattoos/pigmented nevi and near pigmented scars. The handpiece of the machine is heavy and this needs a steady wrist to achieve the “in-motion” procedure. In case of in-motion technique, it is always advisable to divide large fields like abdomen, back and limbs into grids to ensure optimal dosage in all areas.

Postprocedure Minimal transient erythema may be observed in some patients. Open areas may be covered up with sunscreens. The sapphire tip of the handpiece needs to be cleansed off the jelly immediately to prevent drying of the same. The hair root and buried part of the bulb hair will be extruded over the next week following the treatment. About 5–10% patients may observe a self-limiting folliculitis in the areas while the upper lip area may show persistence of hairs near the angle of the mouth.

COMPLICATIONS IN LASER SURGERY Postinflammatory Hyperpigmentation PIH may become apparent between 2 weeks and 2 months after postoperative erythema has resolved. As soon as re-epithelialization is complete and erythema is resolved, topical bleaching regimen may be prescribed. Post-inflammatory hyperpigmentation is usually reversible over time. It can take between 3–6 months and can be easily concealed with makeup.

Hypopigmentation May be clinically apparent 1 to 6 months after treatment. It is more commonly observed on darker skin types and often related to the depth of resurfacing or to the usage of inappropriate laser parameters. Sun exposure must imperatively be avoided; it may actually worsen the change of pigmentation and its duration. It may last for 6–12 months and rarely could be permanent.

440  Lasers in Dermatological Practice

Proper eye protection is essential. An eye shield is a must if treatment is within orbital rim.

Technical Aspects Smoke evacuator designed for surgical lasers: Connect tubing and cables of the smoke evacuator as per manufacturer’s guidelines and as indicated in the operator’s manual. Make sure filters have still operating hours left. In addition, the physician should wear a micron filtered mask during procedures.

BOOKS 1. CO2 laser resurfacing: Confluent and fractionated. Cosmetic Dermatology: Products and Procedures; 2010. 2. Hruza, GJ; Avram Dover JS. Lasers and lights, Procedures in Cosmetic Dermatology; 2013. 3. Narurkar VA. Dermatology Clinics. Cosmetic Dermatology. Ablative and Fractional Ablative Lasers. 2009. 4. Pfenninger JL, Stulberg DL. Dermatologic and Cosmetic Procedures in Office Practice. Usatine RP; 2012.

Bibliography 1. Duffy K, Grossman D. The Dysplastic nevus. From Historical perspective to management in the modern era. JAAD 2012;67;1-30. 2. Karn D, KCS, Amatya A, Razouria EA, Timalsina M, Suwal A. Q-Switched neodymium-doped yttrium aluminum garnet laser therapy for pigmented skin lesions: Efficacy and safety. Kathmandu Univ Med J (KUMJ). 2012 AprJun;10(38):46-50. 3. Lee JB, Chung WG, Kwahck H, Lee KH. Focal treatment of acne scars with trichloroacetic acid: Chemical reconstruction of skin scars method. Dermatol Surg. 2002 Nov;28(11):1017-21. 4. Manstein D, Herron GS, Sink RK, et al. Fractional photothermolysis: a new concept for cutaneous remodeling using microscopic patterns of thermal injury. Laser Surg Med. 2004;34:426-8. 5. Ros EV, Yashar S, Michael N, et al. Tattoo darkening and non-response after laser treatment: A possible for titanium dioxide Arch Dermatol. 2001;37;33-7. 6. Sardana K, Garg VK, Bansal S, Goel K. A promising split-lesion technique for rapid tattoo removal using a novel sequential approach of a single sitting of pulsed CO2 followed by Q-switched Nd: YAG laser (1064 nm). J Cosmet Dermatol. 2013 Dec;12(4):296-305. 7. Weiss ET, Geronemus RG. Combining fractional resurfacing and Q-switched ruby laser for tattoo removal. Dermatol Surg.2011;37(1):97-9.

Chapter

16

Medicolegal Aspects of Lasers in Dermatological Practice Anil Aggrawal, Kabir Sardana

Introduction The use of high energy light sources [laser, intense pulsed light (IPL)] is a booming industry. Lasers were introduced in the specialty of dermatology in the mid-1960s. Since then, their wide acceptance and use provide striking evidence of their extraordinary ability to treat, precisely and effectively, a number of skin diseases that were previously incapable of being managed by other medical or surgical methods. Continued evolutionary changes in both the laser IPL technology and the understanding of the mechanisms involved in the laser–tissue interaction have improved the precision with which cutaneous laser surgery can be performed and have also increased the indications for it.

Typical complications Laser and intense pulsed light (IPL) treatments are, however, not without their hazards, especially at the hands of a non-specialist, as has become the trend lately. Typical complications arising from laser and IPL treatments are allergic reactions (due to unknown tattoo inks), blistering, burning, color changes (with removal of permanent make-up), contact dermatitis (after hematogeneous dissemination of the allergens), crusts, folliculitis, hypertrophic scarring/keloids, localized herpes virus infections, loss of pigmentation/hyperpigmentation (depending on laser/IPL setting, skin type, and preinterventional or postinterventional sun exposure), paradoxical hair growth (especially with IPL technology) and pruritus. The biggest problems are the treatment of pigmented lesions of uncertain benign/ malignant nature without prior diagnosis or histological controls, which often leads to the appearance of an atypical postoperative recurrent nevus or pseudomelanoma. Sometimes, amelanotic melanomas may be allowed to progress without detection and may even metastasize. Laser burns is another injury which may occur during hair removal. Although usually safe and well tolerated, with the widespread use unexpected side effects can be seen. In recent years, a new laser technology has been

442  Lasers in Dermatological Practice

introduced to aid in pain and other side effects in laser applications. Diode laser systems are produced for this technology. The major disadvantage with this laser is the gel application during procedure. Epidermal burn reactions can occur due to accumulated debris on the guide (Kacar SD). A number of laser specific complications are detailed in a separate chapter and needless to say, the patient should be told about the complications and the course of the sequelae in advance (Table 16.1). A list of conditions for which litigation was initiated in a study (Jalian HR) is listed in Table 16.2. It is not surprising that as laser hair removal is the most common “out sourced” procedure, it is the most common cause of litigation. Apart from that, note that in some cases using the laser for indications that are better treated by other means can be a valid cause for litigation. The classic examples are psoriasis and vitiligo. For both, these the excimer laser/light are used which are in no way superior to other forms of therapy, including phototherapy. If not charged (as in certain institutions), it may not be an issue, but if charged, can be a “recipe” for trouble. Nonsurgical sculpting and tightening are classic examples of indications where there is a mismatch of expectations and results, unless patients are counseled well in advance.

Who is qualified to do Laser Surgery? This question is often asked, especially as the cosmetic laser trend continues to grow, a number of unqualified practitioners have started doing laser cosmetic procedures. Physicians are also increasingly using physician extenders (PE) to assist them with such procedures. A physician extender [most commonly a nurse practitioner or physician assistant] is a health care provider who is not a physician but who performs medical activities typically performed by a physician. Without appropriate supervision and training one can expect Table 16.1 Injuries sustained because of laser surgery (Jalian HR, et al.) Burns Scars Pigmentation Disfigurement Emotional distress

Physical suffering Erythema Diminished quality of life Ulceration Embarrassment

Eye injury Death Disability Infection

Table 16.2 Laser procedures performed resulting in litigation (Jalian HR, et al.) Hair removal Rejuvenationa Vascular Leg veins

Tattoo Neoplasm Scar Pigmentary disorder

Pigmented lesion Others *

* These cases included 6 cases in which the specifics of the procedure were not disclosed, 2 cases related to fat removal, 1 case of skin tightening, and 1 case of psoriasis treatment.

Medicolegal Aspects of Lasers in Dermatological Practice  443

a higher incidence of complications for these nonphysicians (Goldberg). At many places, most notably wellness facilities, cosmetology institutes, and hair and tattoo studios, PEs are employed solely, without any supervision by a trained dermatologist. The underlying legal premise supporting this situation is that these practitioners are not treating disease. Thus, there is no need for a diagnosis by a physician, and procedures may be performed by trained laypersons. While The American Society for Lasers in Medicine and Surgery, American Academy of Dermatology, and the American Society for Dermatologic Surgery have all developed guidelines for PE using lasers in the dermatologic and cosmetic laser setting, though corresponding Indian societies have failed to formulate similar guidelines. In the US, according to most guidelines a PE, where allowed by state law to do laser treatments is required to have a supervising physician on site and immediately available while the laser procedure is being performed. Since lasers may have untoward effects on the body if incorrectly used, only those persons are legally allowed to use lasers who are qualified in medicine and surgery, i.e. who hold a proper MBBS degree from an MCI recognized medical college. Section 27 of The Delhi Medical Council Act, 1997 deals with “False assumption of Medical Practitioner or Practitioner under this Act to be an offence” and states, “Any person who falsely assumes that he is a medical practitioner and practices the modern scientific system of medicine, shall be punishable with rigorous imprisonment which may extend up to three years or with fine which may extend up to Rs. 20,000 or with both.” A study by Hammes S, et al. found that the following complications occurred, with laser procedures performed by medical laypersons: 81.4% pigmentation changes, 25.6% scars, 14% textural changes, and 4.6% incorrect information. The sources of error were the following: 62.8% excessively high energy, 39.5% wrong device for the indication, 20.9% treatment of patients with darker skin or marked tanning, 7% no cooling, and 4.6% incorrect information.

Vicarious Liability A qualified medical practitioner, however, may ask a PE to assist him in laser surgery. In such cases, the medical practitioner would be liable for all damages (even if actually committed by PE) under the doctrine of vicarious liability (syn., vicarious responsibility). It simply means that a person “A” is liable for the wrongful acts or omissions of “B”, if “B” was under A’s control. It arises under the principle of ‘respondeat superior’, which holds that the employer is responsible not only for his own negligence but also for the negligence of his employees, if such acts occur in the course of the employment and within its scope. It is also sometimes known as “captain of the ship” doctrine. As

444  Lasers in Dermatological Practice

stated above, this doctrine becomes applicable when the superior had the “right, ability or duty to control” the activities of a violator.

Civil and Criminal Negligence Though cases in consumer forums are common against laser clinics to the best of our knowledge criminal cases are not usually filed. But we will dwell on this aspect as the difference between the two depends largely on how the police interprets the same (Flow chart 16.1). Flow chart 16.1: Civil and criminal negligence. Action along the dotted line generally does not occur, but is possible

Medicolegal Aspects of Lasers in Dermatological Practice  445

There is no absolute or watertight differentiation between cases of civil negligence and criminal negligence. If a patient decides to go to a civil court or consumer forum to ask for compensation, it is called civil negligence. However, if the harm caused to the patient is so great (e.g. death) that he decides to report the matter to police instead, it becomes a case of criminal negligence. A patient can simultaneously sue the doctor in a civil court and can lodge a complaint with the police also. Thus, the same case would be fought in both civil and criminal courts. In such a case, the same negligent action of the doctor would be civil as well as criminal in nature. The differentiation between the two, thus, depends on patient’s action (Flow chart 16.1 and Table 16.3). Also, it is important to understand the difference between negligence and misconduct (Table 16.3).

Components of Medical Negligence For a case of medical negligence to be established, the following components must be present (4Ds). These are the components required for civil compensation. For criminal charges they do not apply (e.g. Section 336 07 IPC is applicable, even if no damage occurs).

Duty The doctor begins to owe a duty towards a patient (i) as soon as he agrees to treat him (ii) when he is in emergency (S12(2) Clinical Establishments Act 2010). A doctor–patient relationship between the doctor and the patient is established at that point in time. Doctor–patient relationship is not formed Table 16.3 Differences between professional negligence and professional misconduct Trait

Professional negligence

Professional misconduct (syn. Infamous conduct, ethical negligence, ethical malpraxis)

Offence

Absence of reasonable care and skill in the treatment of patient

No absence of care and skill, but the doctor did not adhere to the ethical standards befitting a doctor

Duty of care towards the patient

The doctor must have a duty towards his patient, which he neglected

No such duty is necessary. Doctor may be accused of professional misconduct even in the absence of such duty, e.g. dichotomy, or when he puts up an unusually large sign board

Damage to the patient

Must be present

Need not be present

Trial by

Civil or Criminal Court

Medical Council of India or State Medical Councils

Punishment

Imprisonment or fine

Warning or erasure of name from the medical register

Appeal

In higher court

To State or Central Governments

446  Lasers in Dermatological Practice

when patient is not in emergency, and the doctor did not agree to treat the patient. Remember in all laser cases, if the doctor initiates treatment, the duty is automatically assigned.

Dereliction of Duty Once the presence of duty has been established, there has to be a dereliction of duty on the part of the doctor, i.e. the doctor should have been negligent in performing his duties towards the patient. The interpretation is open to debate but if due consent is taken, checklist followed and patient instructions given in the Appendix of the book this is difficult to prove !

Damage 1. The damage must occur as a result of dereliction, and it must be foreseeable. 2. Even if doctor is negligent, patient cannot sue him for compensation, if no damage has occurred. He can however be sued criminally u/s 336 IPC (Flow chart. 16.1). 3. Some examples of possible damages are as follows: i. Aggravation—of a preexisting condition (Paradoxical hypertrichosis with hair removal lasers). ii. Diminishing patient’s chances of recovery. iii. Expenses incurred—e.g. hospital and medicine expenses, special diet and of course lasers ! iv. Pain and suffering—causing either physical or mental [embarrassment, fright, humiliation] pain or increasing it. v. Loss of earning—due to absence from work (may be the case if a resurfacing is done, which is not commonly done nowadays. vi. Loss of potency. vii. Prolonging the illness. viii. Reduced enjoyment of life, e.g. loss of a limb or sense. ix. Reduction in expectation of life. x. Death.

Direct Causation 1. Damage must result directly from dereliction (proximate cause), and not from any other cause. 2. Proximate cause refers to a cause, which in natural and continuous sequence, unbroken by any efficient intervening cause, produces the injury, and without which the injury would not have occurred. It may also be conceived of as a series of “falling dominoes”. If the final domino

Medicolegal Aspects of Lasers in Dermatological Practice  447

[damage] can logically fall by “pushing” the first domino [dereliction], the “push” is the proximate cause [direct causation] of fall of final domino. There is a defense of Novus actus interveniens, which is based upon lack of this component. It refers to a situation, where the doctor has been negligent, but a completely unexpected and unforeseen act happened, which further worsened the patient’s condition. The new act intervening should be completely unexpected and unforeseen. Sometimes, referred to as an “Act of God”. It must break the natural chain of causation between the act of negligence and the resulting damage (Fig. 16.1A and B). Thus, injury no more remains a proximate cause of doctor’s negligence. This defence is not available in criminal negligence or criminal activity. Some examples below would help understand each component above: Example 1 (Duty): Patient comes to a doctor for treatment of keloid by laser. Doctor demands his professional fee. Patient is not able to give. Doctor refuses treatment. Patient does not take treatment from elsewhere. After some time keloid becomes infected. Patient suffers injury. Patient cannot sue doctor, because no duty was established. Example 2 (Dereliction): Patient comes to a doctor for treatment of hypertrophic scars by laser. Doctor treats him with correct laser, but hypertrophic scars remains. End result is that the patient is not treated. Patient cannot sue, as there was no dereliction on the part of doctor. Example 3 (Damage): Patient comes to doctor for facial laser resurfacing. Doctor agrees to treat (duty established). Doctor uses lasers carelessly so patient develops blistering and burning (damage). Patient can sue doctor. If though despite doctor using lasers carelessly, patient does not suffer any damage, patient cannot sue doctor. Example 4 (Direct causation): Patient comes to doctor for laser removal of tattoo. Doctor agrees to treat him (duty is established). Doctor fails to use

A

B

Figs 16.1A and B: Concept of (A) proximate cause and (B) novus actus interveniens

448  Lasers in Dermatological Practice

the right laser (dereliction occurs) ® Tattoo is not removed. After ten years, the tattoo becomes cancerous due to nature of dye within (damage occurs). Patient sues first doctor for not using the right laser. He cannot succeed because although, there was duty, dereliction and even damage, but damage was not a direct result of doctor’s dereliction. This of course is open to debate, as it is theorized that Azo dyes used in tattoo can potentially cause psudolymphomas, though whether laser can aggravate this is unknown. Again removal of moles (common acquired melanocytic nevi) by lasers, have been linked though controversially to malignancies. This is almost unheard in India, but is reported in world literature.

How to prevent malpractice claims A interesting insight into the types of complaints entertained in litigations in USA is given in Table 16.4. A few of them that can be of concern in India include deceptive trade practices, failure to properly hire, train, or supervise staff, failure to select appropriate laser and/or setting, not trained and/or certified to operate laser and failure to properly calibrate and maintain lasers. We are adding one more to this list, which can be a valid cause of a civil suit, using non US FDA /CE approved lasers. With no certification in India, these are the certifications essential, which I daresay do not exist for most lasers sold. Thus prevention is better than facing malpractice claims. Following simple rules will help prevent malpractice claims to a great extent.

Table 16.4 Common complaints in litigations in laser cases Cause of action

Specific allegations

Lack of informed consent

Failure to properly hire, train, or supervise staff

Fraud

Failure to properly perform treatment and/or operate laser

Loss of consortium

Failure to select appropriate laser and/or setting

Assault/battery

Failure to warn and/or inform of risk

Strict products liability

Failure to conduct test spot

Breach of contract

Not trained and/or certified to operate laser

Infliction of emotional distress

Failure to recognize and/or treat injury

Negligent misrepresentation

Failure to properly calibrate laser

Gross negligence

Failure to maintain laser

Recklessness

Failure to biopsy

Deceptive trade practices

Failure to supply goggles

Medicolegal Aspects of Lasers in Dermatological Practice  449

Patient Information and Documentation Many malpractice claims arise due to lack of patient information, or sometimes inflated claims. Physicians should ensure that they themselves inform the patients and do not delegate the responsibility to nurses or paramedical staff. Informed consent must also be taken by dermatologists themselves, and it must be written. A patient’s signature on a preprinted consent form, which has not been preceded by a discussion with the physician does not grant doctors free rein, and in the event of a legal dispute, such a form can be declared invalid. The optimal procedure consists of a thorough discussion, after which the patient is given a consent form to which handwritten additions are made as necessary. Detailed information should be provided about the diagnosis; the nature, extent, and process involved in the planned treatment; potential short- and long-term adverse effects; possible alternative treatments; and the costs to be expected. Rare concomitant effects, adverse effects, and risks should also be discussed if they are typical for the procedure in question. Treatment should not be performed on the same day the discussion is held; patients should have the chance to make a decision without being pressured for time and without being affected by the psychological burden of the procedure awaiting them. Patient documentation should include information about discussions between the physician and patient, the preoperative diagnosis and histologic findings (to whatever degree present or necessary), the indication for laser treatment, test treatments, the kind of anesthesiology, the kind of laser and parameters of application, the results of treatment, and any concomitant reactions, adverse effects, and complications (intra- or postoperative, infections, late complications, etc.). Especially in the case of cosmetic procedures, additional photographic documentation is recommended. This is relevant from a forensic perspective, as well as being useful if the patient should question the success of the treatment. Some clinicians prefer to write a risk, benefit and alternatives (RBA) note together with a written informed consent. It is wise to seek informed consent for each type of laser that is operated by the physician. Each laser system functions in a unique fashion. The same laser created by various competitors may differ in terms of treatment settings and potential side effects. For this reason, establishing a relationship with the laser company for support is advantageous for the physician. Furthermore, ensuring that the medical device is FDA approved for patient therapy could minimize liability. Though a detailed consent form is given in the Appendix of the book, we are detailing the essentials in a conset form, which can be remembered by the mnemonic LASER (Abel Torres, et al.) (Table 16.5).

450  Lasers in Dermatological Practice Table 16.5 Ideal components of a consent form Liability waiver

A patient needs to be told that Laser procedures are not reimbursable and no other procedure will be shown in lieue of it !

Anesthesia type

There are risks associated with all types of anesthesia, including topical (see Chapter on Drugs)

Surveillance

Observations, outcomes and side effects on the postoperative record documents treatment course in the best interest of the patient

Expectations

A no guarantee clause should be emphasized as no indications has definite cures

Revocation of consent

Offer the option of letting the patient refuse treatment at any time especially if it alters outcome

Snapshot

Photogarphs are to be taken specifically for documenting results and are confidential unless specified

Training Malpractice claims are mostly due to professional errors, which in turn, are due to lack of training and experience. Thus, training must be strengthened. The ideal method of ensuring thorough training, is to establish teaching centers for laser treatment in qualified, certified offices or clinics. In such institutions, guidelines should be taught on topics including didactic, hands-on, and laser-specific clinical techniques. Standards of practice are sometimes handled as if they are top secret information. This should not be done; instead, they should be officially instructed and published. In the US and some other developed nations an oral and written examination is a must for every dermatologist in practice. It serves as a rational and fair strategy to assess theoretical and practical proficiency objectively after a defined period of continuing education is completed. Sadly, in India, there is no such program. If such programs are started and widely followed, these may serve to reduce professional errors, and in turn, malpractice claims. In case a physician is using lasers in dermatology, he must have dermatologic training in addition to laser-specific training.

Do not Make Unrealistic Claims It has been seen that many malpractice claims originate as a result of failed patient expectations, which in the first place are raised very high almost to unrealistic levels. Some examples are “removal of 80–90 % of the hair in 2–3 sessions” or “1064 nm Nd:YAG laser is superbly suited for removing moles and dark hyperpigmentation spots”. Experience has shown that whenever the patient has been given realistic assurances, the incidence of malpractice claims remains low.

Medicolegal Aspects of Lasers in Dermatological Practice  451

Handling the Press Proliferation of print and electronic media in India, has caused journalists to look around for cases to feed their 24 × 7 news channels. Medical malpractice cases, being inherently potential TRP enhancers are among the most hotly pursued stories by print and TV journalists. If for example, a patient has been injured by laser treatment, the journalist would approach some top laser practitioners and would like to know their views on it. It would be wise for laser practitioners not to criticize their colleagues for 2 reasons—it is unethical to pass derogatory remarks against a colleague, and secondly, the case may be in court and any comments may cause an unduly adverse outcome in the case. The results of some surveys indicate that doctors need to be trained to handle the press.

How to handle a malpractice claim if it does occur? Involvement in a lawsuit as a defendant may be in a civil or criminal case. Experience has shown that a vast majority of medical malpractice cases in India are civil cases, which is good news for doctors, because at most they would entail payment of damages and not imprisonment. A minority of cases [generally those in which death has occurred], are fought in the criminal court, in which there may be imprisonment to the doctor. However there is no bar for a patient to go to a criminal court even for minor injuries [s 337 IPC] or most surprisingly even if no injury has occurred [s 336 IPC]. The latter case may be unbelievable to some, but there is a distinct theoretical possibility of this occurring. The analogy is fast, reckless driving through a city. Even if no one is injured, the driver is still liable, because he could have caused injury by engaging in such a rash and negligent act. Similarly, if a doctor is rash and negligent in using lasers, and if a patient has ample proof of it, he can approach the court, even if no injury has occurred to him. Thankfully such situations are extremely rare. It must be noted that a patient can sue for compensation in a consumer court only if he has paid fees to the doctor. If no professional fees has been paid, the patient cannot invoke a consumer court, but he can still approach a civil court under tort law. Generally, such cases drag on for years in India and are a cause of worry for doctors. The most worrying cases are criminal cases, in which the patient complains to the police, and the police lodges a case against the doctor. In laser applications of dermatology, such cases are likely to be extremely rare, simply because grave laser injuries are virtually unknown, and as already stated, the patient generally would refrain from going to the police until and unless the injury is very grave and debilitating.

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Countersuits One way to deal with a suit is filing a countersuit. A countersuit is an action brought by a physician against the patient (the plaintiff in the original malpractice action), as a retaliation strategy. It is based on the maxim, “attack is the best form of defense”. This strategy works best, if the laser practitioner is sure that the malpractice claim is malafide and unjust. The countersuit movement began in the mid-1970s with enthusiastic support by the medical profession in response to the dramatic rise in medical malpractice suits, many of which were perceived as lacking substantial merit. It must be remembered that courts would not taken this approach very positively if the laser practitioner was actually at fault. They have rejected most countersuits, which were filed merely as an attacking policy. Courts follow a public policy interest in ensuring that injured parties have free and open access to the judicial system

Alternative Dispute Resolution (ADR) A far simpler and better approach is alternative dispute resolution or ADR. It refers to dispute resolution techniques that help plaintiffs and defendants resolve conflicts outside of the courtroom. It is advantageous to both patients and doctors. Patient can save time from litigation and focus efforts on healing. Money saved on lawyers and court goes directly to the patient. Many hospitals in the US have embraced “early apology” programs, where physicians and hospital administrators reach out to the injured patient and express sympathy about the adverse event. This protects the natural doctor– patient relationship as well as encourages dialogue.

Mediation and Arbitration The most popular ADR techniques are mediation and arbitration. They differ in both their binding nature and their formality. Mediation is simple negotiation that is aided by an impartial mediator. It is nonbinding, meaning that if a settlement cannot be reached, the plaintiff may pursue his claim in court. Arbitration is more court-like, with an arbiter hearing both sides much like a judge would. Similarly, there are rules for how and when to talk, and how to present evidence. Most importantly, it is binding, meaning that the judgment of the arbiter is final and litigation is not an option.

Mediation Mediation has had excellent success where implemented, both in terms of cost-containment and satisfaction for both parties. From the plaintiff’s perspective, mediation offers more flexibility than litigation, which only offers money as a remedy. Experience has shown that patients who come

Medicolegal Aspects of Lasers in Dermatological Practice  453

for laser cosmetic surgery are, by and large from upper echelons of society and often do not engage in litigation for money. Many sue for nonmonetary reasons, such as the desire for disclosure of information or the desire to hear an apology or explanation of what went wrong. In the US, for example, rather than just receiving money, some plaintiffs wish for a scholarship to be established in their family’s name, or like their deceased’s story told to incoming nurses or medical students to help prevent similar adverse events in the future. Similar trends are appearing among the rich patients in India. For these reasons mediation often suits plaintiffs’ needs better. Nonmonetary aspects like the ones mentioned above are withheld in a litigious environment.

Arbitration Arbitration is different from mediation. It is more acrimonious and expensive, being more trial-like than mediation. It is longer and more expensive than mediation, but much shorter and less expensive than court trials. Like court trials, arbitration can only offer money as a form of redress, eliminating the more creative and satisfying solutions offered in mediation.

Pretreatment Arbitration Agreement Laser practitioners may want to undergo a pretreatment arbitration agreement. Under this arrangement, patients agree to arbitration as a condition of being seen in the first place. This has become an increasingly popular form of arbitration in the US. However, it suffers from the great disadvantage that it is awkward to discuss adversarial postures during the initial physician–patient visit itself.

Benefits of Mediation and Arbitration Benefits of mediation and arbitration are almost 100% avoidance of litigation. Thus, these are very appealing to everyone alike—doctor, patient and even the insurer, as even a successful defense can cost a lot. There is a private and informal setting outside of the courtroom. In case of arbitration, the decision of arbiter is binding and there are no appeals process. It occurs as scheduled and without delay, unlike many court cases. Damage awards tend to be more predictable and usually are more in line with settlement values than those afforded by court trials.

Conclusion A detailed patient information sheets, consent form and postprocedure check list has been given in the Appendix of the book which can help to avoid unnecessary medicolegal issues.

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Laser cosmetic surgery can legally be done only by a person qualified in modern medicine and surgery. Any other person engaging in laser cosmetic surgery can only do so under supervision of a qualified dermatologist. If dermatologist is sure, the malpractice suit by the patient is malafide, he can respond by filing a countersuit. If on the other hand, he knows he has been negligent, the best approach is mediation and arbitration.

Bibliography 1. Abel Torres, Tejas Desai, Alpesh Desai, and William Kirby. Medicolegal Issues (Documentation/Informed Consent). K. Nouri (ed.), Lasers in Dermatology and Medicine, DOI: 10.1007/978-0-85729-281-0_31, © Springer-Verlag London Limited 2011 2. Goldberg DJ. Laser physician legal responsibility for physician extender treatments. Lasers Surg Med. 2005;37(2):105-7. 3. Greve B, Raulin C. Professional errors caused by lasers and intense pulsedlight technology in dermatology and aesthetic medicine: preventive strategies and case studies. Dermatol Surg. 2002;28(2):156-61. 4. Hammes S, Karsai S, Metelmann HR, Pohl L, Kaiser K, Park BH, Raulin C.Treatment errors resulting from use of lasers and IPL by medical laypersons:results of a nationwide survey. J Dtsch Dermatol Ges. 2013;11(2):149-56. 5. Jalian HR, Jalian CA, Avram MM. Common causes of injury and legal action inlaser surgery. JAMA Dermatol. 2013;149(2):188-93. 6. Jalian HR, Jalian CA, Avram MM. Increased Risk of Litigation Associated With Laser Surgery by Nonphysician Operators. JAMA Dermatol. 2013 Oct 16. doi:10.1001/jamadermatol.2013.7117. 7. Kacar SD, Ozuguz P, Demir M, Karaca S. An uncommon cause of laser burns: The problem may be the use of gel. J Cosmet Laser Ther. 2014 Feb 10. [Epub ahead of print]

Chapter

17

Complications and their Management Kabir Sardana

Introduction There are very few studies that examine complications across different lasers. Most studies are focused on a particular device. A recent study (Zachary Zelickson) that used the Manufacturer and user facility device experience (MAUDE) database from 2006 to 2011 found that the most common cosmetic laser treatments with complications was hair removal. Thirty percent of laser surgery complications were due to user error, 20% device malfunction, and 4% due to patient error.

Common Devices and their complications Lumenis had the most (204) complications, followed by Candela (66), and Rhytec (65). The list of commonly reported device causing side-effects are given in Table 17.1. Intense pulsed light (IPL) devices had the most Table 17.1 A summary of complications of lasers * Device

Complications reported

IPL Plasma RF monopolar CO2 810 diode 1,064 nm Nd:YAG 755 nm alexandrite laser NA fractional (NAFR) Pulsed dye laser Nd:YAG

142 65 59 57 39 37 29 21 15 6

Ablative fractional RF (fractional, needle, suction)

3 2

Thulium Fractional CO2 USG

1

*(MAUDE): US Food and Drug Administration (FDA) manufacturer and user facility device experience (Zachary Zelickson et al)

456  Lasers in Dermatological Practice

(142) complications, followed by plasma radiofrequency (RF) (65), and RF monopolar devices (59). The five most common complications were burns (36%), scarring (19.4%), pigmentation damage (8.5%), blistering (2.4%), and infection (8%). In darker skin types, PIH is by far the most important sideeffect. A list of device specific complications is given in Table 17.2. The IPL and the RF report the highest complications while the fractional devices and Qsw lasers are safer. Notably the Er:YAG has no complications reported which makes it the ideal laser in Indian skin type for ablative procedures. With little by way of reporting, there is no data base in India of the side effects, but the incidence would largely reflect the studies published.

Overview of Common Complications Pain This is a universal feature of all laser procedures and a certain degree of interindividual variation is seen.

Prevention and Treatment Cooling devices have played a large role in minimizing pain and optimizing treatment of specific lesions and are crucial in pigmented skin. Table 17.2 A list of common side effects associated with common laser devices* Device

Common device complications

Intense pulsed light

Burn Blister Scar Pigmentation

Plasma Resurfacing

Infection Scar Burn Pigmentation

Radiofrequency monopolar

Burn Blister Scar Pigmentation

Carbon dioxide

Scar Burn Pigmentation

810 diode

Burn Pigmentation Scar Blister

*(MAUDE): US Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience

Complications and their Management  457

The use of anesthesia is important, though in some, it may not be required. For fractional lasers we have found that pretreatment icepack cooling is adequate for most patients. This also has the added advantage of a modicum of cost saving for the patient. Some lasers (the PDL) often do not require pretreatment anesthesia. In some case, infiltration anesthesia may be required. One protocol includes topical lidocaine/tetracaine application with another approach being a combination of hot compresses, topical lidocaine and oral anxiolytics (vicodin, diazepam or ketorolac) for resurfacing procedures.

Erythema and Edema They are both expected to occur and in fractional lasers, they are usually transient (Fig. 17.1). Some reasons for excessive edema include, excess pulse stacking or passes, treatment of periocular areas, and use of high energy settings. Concomitant use of tretinoin is also a predisposing factor.

Prevention and Treatment A simple method to resolve this is the use of post-treatment cold-packs, head elevation and short-term use of topical steroids (Fucidin HTM).

Crusting and Vesiculation Crusting and vesiculation are manifestations of epidermal damage in certain indications (Qsw Lasers). It is bound to occur and the patient should be

Fig. 17.1: Edema and erythema seen immediately after Er:Glass therapy for scars. Mild and Reversible. Icepack suffices in most cases. A mild steroid can be used for 1–2 days to prevent PIH

458  Lasers in Dermatological Practice

forewarned about it (Fig. 17.2). In fractional lasers, a certain degree of posttherapy “areal density” marks are also evident, which resolve in 3–5 days (Fig. 17.3).

Prevention and Treatment 1. In most non-ablative procedures, we usually give topical aloe vera gel (JulaTM/Aloekem 75TM) or a bland non-sensitizing moisturizer

Fig. 17.2: A case of segmental lentigines post Qsw Nd:YAG (day 2). Crusting is seen, and a bland moisturizer (petroleum jelly, CetaphilTM cream, JulaTM gel) is given till the crust falls off. Judicous sunscreen use is advised

Fig. 17.3: Crusting seen corresponding to the MTZ patterns of a fractional Er:Glass (Lux Palomar). Mild and reversible. Sunscreen with a topical non-HQ/tretinoin cream( MelaglowTM) is used for 14 days

Complications and their Management  459

(CetaphilTM/PhysiogelTM) with a topical steroid (Fucidin HTM) and advise the patient not to remove the crust manually. Saline compresses are advised which help in rapid removal of the crust. 2. For ablative procedures, a petrolatum based preparation is advisable (EpicreamTM, EucerinTM, SecaliaTM) with the use of a non-sensitizing antibiotic (Fucidin). 3. Sunscreen (physical block) is advised till complete healing.

Purpura Purpura results when there is damage to small vessels and subsequent extravasation of red blood cells. It is common following treatment with the PDL and is, in fact, a therapeutic endpoint when treating certain vascular lesions with short pulse durations and high fluences (so-called purpuramode). In case IPL is used for PWS, a bruise-like appearance frequently occurs which can take 5–6 weeks to subside (Fig. 17.4) and is part of the therapeutic reoponse.

Prevention and Treatment All patients should be off anti-coagulant and anti-platelet agents at least 3–4 days prior to the planned procedure, which should be discussed with the physician. Lowering fluence and increasing pulse duration (in the PDL) can help minimize purpura. As port wine stains and hemangiomas, cannot be effectively treated with non-purpuric parameters, patients should be aware of the potential of downtime.

Fig. 17.4: A case of PWS treated with a IPL. Note the bruise-like darkening visible that precedes resolution

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Dyspigmentation/Post-inflammatory Hyperpigmentation (PIH) Dyspigmentation can be transient or permanent and takes on two forms: hyper-or hypopigmentation. Hyperpigmentation is a common manifestation of post-inflammatory change in the tissue. It generally appears 3–4 weeks postoperatively and spontaneously resolves over the next several months, though permanent hyperpigmentation can occur. Hypopigmentation occurs when lasers inadvertently target melanin. QS lasers and IPL often cause a transient hypopigmentation during treatment due to the absorption of light by melanin and subsequent injury to individual melanosomes. Rarely, permanent hypopigmentation can appear 6–12 months after resurfacing procedures (“delayed hypopigmentation”) due to thermal injury (Fig. 17.5). In general, patients with dark or tanned skin have a greater risk of dyspigmentation. For such patients, treatment with lasers with shallower depths of penetration (i.e. shorter wavelengths and smaller spot sizes) confers greater injury to epidermal melanocytes and should be avoided.

Prevention and Treatment PIH 1. Lasers with longer wavelengths and larger spot sizes should be used as the depth of penetration will be greater and risk of injury to epidermal melanocytes smaller. As a rule, a test spot and lower fluences should be used in pigmented skin.

Fig. 17.5: A case of Becker’s nevus treated with IPL. Note the hypopigmentation corresponding to the “footprint’’ of the probe

Complications and their Management  461

2. Though preoperative sunscreen and alpha-hydroxy acids or bleaching agents combined with a topical steroid may help, this has never been satisfactorily been proved in any study, to prevent PIH. In fact, a prospective study of 100 patients undergoing CO2 laser resurfacing found no significant difference in the incidence of post-inflammatory hyperpigmentation between patients pretreated 2 weeks with glycolic acid cream or combination tretinoin/hydroquinone creams versus no treatment (West TB). 3. In most non-ablative procedures, we usually follow the following schedule: a. First 7 days, a combination of aloevera (Aloekem 75TM/JulaTM gel) in the morning with fucidin cream at night. b. Second 7 days continue the aloe vera and add a non-HQ/tretinoin cream at night. We prefer MelaglowTM as it inhibits two stages of melanogenesis. (4% niacinamide, 0.2% soy isoflavanoid and 0.1% glabridin and 2% kojic acid). Another option often employed is a steroid antibiotic combination. Here, the relative potency must be understood and thus Fucidin H or Fucibet is better than Flutibact. This is as Flutibact ointment as per the American Classification contains fluticasone propionate ointment 0.005% which is a Class 3 steroids as opposed to betamethasone valerate cream (class 5) which is a part of Fucibet and Hydrocortisone (class 6) which is a component of Fucidin H. It is inadvisable to use gentamicin/ neomycin due to their allergenic potential or mupironic acid as it may lead to resistance. c. After 21 days, we stop the steroid and continue the use of the depigmenting cream. d. A physical block sunscreen is preferred for the duration of post treatment care. Though we have discussed the demerits of using laser toning previously, it, must be reemphasized that in Indian skin, it can cause perilous pigmentary alterations (Fig. 17.6)

Hypopigmentation This is seen either while using a Q-switched lasers (Fig. 17.6) or as a consequence of overuse of topical steroids. For hypopigmentation, use of topical PUVA (oxsoralen and UVA light therapy) has been used to induce melanogenesis, so has been phototherapy (Mysore V). It is this author’s opinion that the use of laser toning for melasma is best avoided as it can lead to unfortunate pigmentary alterations (Fig. 17.6). In all cases, a test spot is a very useful tool as seen in the patient in Figure  17.7. Though the pigmentation resolved in this patient, it is a safe practice to forewarn the patient about the pigmentary sequelae.

462  Lasers in Dermatological Practice

Fig. 17.6: A case of melasma treated with laser ‘toning’ (Qsw Nd:YAG). Note the depigmentation and darkening of the melasma (Courtesy: Dr Shilpa Garg )

Fig. 17.7: A Becker’s nevus, test spot with a Er:YAG laser. Note the hypopigmentation

Scarring Scarring is nowadays rare as it is seen mostly with ablative procedures which are not done so commonly nowadays. The terminology in the literature can be confusing as some texts describe textural change where there is a change in the contour of the skin, truly differentiating it from a permanent scar.

Complications and their Management  463

Causes The most likely cause of scar formation following laser treatment is excessive thermal injury to the treated tissue. Pulse stacking or multiple passes, high energy fluences or inadequate cooling can all precipitate thermal injury. Selection of an appropriate laser and use of the correct treatment parameters, for a given indication, is paramount in avoiding excessive tissue damage and scarring. Patients with a history of recent isotretinoin therapy, keloid scar formation or radiation therapy may be at increased risk for hypertrophic scar formation, following resurfacing procedures. Additionally, postoperative resurfacing complications, such as infection and contact dermatitis, may also lead to scarring. Treatment of certain anatomical locations, including the mandible, anterior neck and infraorbital areas are more likely to scar. Reduced laser parameters are recommended in these areas.

Prevention and Treatment Some signs are useful indicators for impending scarring: 1. Marked erythema or graying of the epidermis during treatment may indicate significant damage and the need to discontinue treatment or adjust parameters. To avoid this multiple test spots with varying fluences and/or pulse durations can be performed prior to treatment, particularly in patients with an increased risk of scarring. 2. Any sign of infection should be treated. We often use levofloxacin 750 mg a day before to 4 days after the laser intervention to avoid such complications. If infection is ruled out, prompt application or intralesional injection of corticosteroids can halt the progression of hypertrophic scars. Intralesional steroids, 5-fluorouracil (5-FU) and laser therapy have proved beneficial in the treatment of hypertrophic scars. PDL treatment has been reported to improve the symptoms, pliability and color and decrease the size of hypertrophic scars.

Laser specific Complications Fractional Lasers The side-effects are mild, reversible and largely minor (Figs 17.1 and 17.3). Though it is believed that the ablative fractional lasers have more side effects, this has not been our experience (Sardana K, 2014). A retrospective evaluation of 961 successive 1,550 nm erbium-doped laser treatments in patients of various skin phototypes (I-V) was conducted by Graber EM et al., only 73 treatments (7.6%) resulted in development of complications. The most frequent complications were acneiform eruptions (1.87%) and herpes

464  Lasers in Dermatological Practice

simplex virus outbreaks (1.77%). Post-inflammatory hyperpigmentation, which occurred with increased frequency in patients with darker skin phototypes. Another study on Asian skin, (Vaiyavatjamai P et al) where the  1550 nm ytterbium/erbium fiber  laser was used found side-effects in only six treatments (3.3%). The most common adverse event was postinflammatory hyperpigmentation (2.2%), while acneiform eruption and desquamation were reported 0.55%, equally. Although, none of the patients received herpes prophylaxis, there were no herpes outbreaks. A summary of the side effects and their management is given in Tables 17.3 and 17.4.

Lasers for Hair Removal This has been discussed in a previous chapter, thus a brief summary will be given here.

Hypertrichosis Several studies have documented paradoxical hypertrichosis following laser hair removal. This primarily occurs after several treatments have been performed on the face and neck of female patients with darker skin types. The mechanism that triggers the conversion of these vellus to terminal hairs is unknown, but may be related to inflammation induced by the laser therapy itself. Management of this uncommon complication is with further photoepilation.

Leukotrichia This is seen when patients are treated with long-pulsed Nd:YAG lasers. These lasers target melanin and penetrate deep enough to reach the hair follicle. Table 17.3 Complications reported with fractional lasers Mild

Prolonged erythema Acne, milia Delayed purpura Superficial erosions Contact dermatitis Recall phenomenon

Moderate

Infection Pigmentary alteration Anesthesia toxicity Eruptive keratoacanthomas

Severe

Hypertrophic scarring Ectropion formation Disseminated infection

Complications and their Management  465 Table 17.4 Complications and their management * Prolonged erythema (>1 month)

Avoid use of irritating topical cream (HQ/tretinoin) Apply mild corticosteroid (Fucidin H) Apply non-steroidal anti-inflammatory agents (Clindamycin/metronidazole gel) LED photomodulation

Milia/acne exacerbation (>1 month)

Discontinue occlusive dressings/ointments It is best to use agents that are non-sticky (Sebamed Clear gel, CetaphilTM cream) Physical extraction of milia Oral antibiotics for acne

Contact/allergic dermatitis

Never use neomycin/gentamicin-based creams Use non-sensitizing creams (Physiogel) Topical/oral corticosteroids

Infection (1–14 days)

Oral antibacterial/antiviral Topical wound care (Fucidin)

Hyperpigmentation (1 month)

Sunscreen (physical block) Topical lighteners (MelaglowTM)

Hypopigmentation (upto 6 months)

Excimer laser Topical photochemotherapy

Hypertrophic scar (1month)

Potent topical corticosteroid Pulsed dye laser

*Brand names mentioned here are indicative only does not indicate any commercial affiliations or endorsement

With subtherapeutic fluence levels, follicular melanocytes may be destroyed in the absence of other follicular injury, resulting in leukotrichosis.

Reticulate Erythema Persistent reticulate erythema has been described in at least 10 patients following hair removal with the Diode laser (Lapidoth M). Pernio and perhaps other connective tissue diseases, as well as high energy fluences, seem to be potential risk factors.

Urticarial-like Plaques Pruritic, urticarial-like plaques have been described following photoepilation. Unlike urticaria, however, lesions may last several days to weeks. Topical and oral corticosteroids and anti-histamines can be used for symptomatic relief.

Burns These are commonly seen with the diode and IPL and with these systems, a preoperative, intraoperative and postoperative cooling is essential

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(Figs 17.8A to C). Also post-treatment, a steroid applications for 3–5 days is advisable. In patients with a acne prone skin ice pack cooling for 1–2 hours after therapy is another option.

Lasers for Pigmented Lesions Leukotrichia Melanin, located in the epidermis, dermis and follicular structures, is the primary chromophore targeted in the treatment of various pigmented lesions. Melanocytes within the hair follicle can be destroyed inadvertently when using high fluences and more deeply penetrating, longer wavelengths. Permanent leukotrichia can result. Limiting the fluences and selecting lasers with shorter wavelengths, if possible, will minimize this complication.

Tissue Splatter and Pinpoint Bleeding Tissue splatter and pinpoint bleeding are expected side-effects of treatment with Q-switched lasers. When tissue targets are heated to destructive levels over nanosecond (Qs) pulse durations, particles can become aerosolized creating tissue splatter and blood vessels can rupture leading to pinpoint bleeding and petechiae. Laser treatment through a water-based gel dressing

A

C

B

Figs 17.8A to C: A series of cases with intraoperative burns and pigmentary alterations (Courtesy: Dr Anil Ganjoo)

Complications and their Management  467

(Fig. 17.9) minimizes tissue splatter and bleeding by acting as a heat sink and protecting the epidermis (Bernstein EF).

Pigmentary Alterations In almost all cases, a transient hypopigmentation occurs as the Qsw lasers can impact on the normal epidermis. Luckily, the pigmentation resolves spontaneously in a few weeks (Fig. 17.10).

Fig. 17.9: Application of a transparent ‘Tegaderm’ dressing before tattoo removal. This prevents tissue splatter but a slightly higher dose is required. The unique advantage is that this acts as a biological post-laser dressing

Fig. 17.10: A case of nevoid linear hypermelansosis after one week of treatment with a Qsw Nd:YAG (532 nm). The hypopigmentation is inevitable but transient

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Tattoos Allergic and Photo-allergic Contact Dermatitis During laser treatment of tattoos, pigment is released from intra- to extracellular sites exposing these antigens to the immune system. Rarely, a type-IV hypersensitivity reaction or photoallergic reaction to the components in the pigment can develop. Cinnabar, found in red tattoo pigment, is the most common contact allergen, while cadmium, which is found in yellow tattoo pigment, is the most frequent photoallergen. Those who have a contact dermatitis to pigment often give a history of pruritus and raised red areas over their tattoo sites. In photodermatitis, this reaction is heightened when exposed to sunlight. Ablative resurfacing procedures can be used for tattoo removal with less risk of mounting an allergic response. However, a localized allergic reaction has been reported to become generalized following CO2 laser removal of a tattoo.

Combustion Treatment of tattoos that contain combustible material should be avoided. Sparks and incipient pox-like scars occur after Qs Ruby laser treatment of a traumatic tattoo. If the composition of the pigment is unknown, a biopsy and/or test spot should be performed to help elucidate the material.

Paradoxical Tattoo Darkening Paradoxical darkening of certain tattoo pigments has been reported with QS laser treatments. The exact mechanism is unknown, but the reduction of ferric oxide to ferrous oxide may play a role. Titanium dioxide may also be implicated in paradoxical darkening through a similar mechanism. Ferrous oxide is found in some red, orange, peach or other skin-colored pigments and titanium dioxide is found in white pigments, often used alone or in conjunction with other colors to brighten them. As such, specific areas of tattoos containing these colors should undergo spot testing prior to full treatment with a Qs laser. Once paradoxical darkening has occurred, correction can be difficult. Repeated laser treatments have been successful, as well as ablative resurfacing procedures.

Lasers for Vascular Lesions Reticulated Purpura Purpura is a common, and usually expect side-effect of the PDL. Often a reticulated pattern of purpura develops after treatment due to the Gaussian distribution of energy of each laser pulse. Overlapping pulses by 18% can minimize this complication.

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Fig. 17.11: Postoperative view of a syringoma case after pulsed CO2 laser. Note the hypopigmentation corresponding to the syringoma which tend to persist for 1–2 months

Ablative Lasers As full face resurfacing is rarely done the side-effects are hardly reported. With Er: YAG, almost no side effects are seen. With the CO2 laser, infections, textural alterations, PIH, and scarring may be seen (Fig. 17.11).

Conclusion Laser-induced complications are largely preventable, except pigmentary alterations in pigmented skin. But a simple rule that this author follows is not to replicate results reported in literature in fair skin types with lasers that have a short wavelength (Qsw ruby or Alex) as they are most prone to pigmentary alterations as the epidermal pigment competes with the laser. The triad of, consent, test spot, and pre-and post-photography are crucial. Methods of cooling, both device based and extrinsic with a good postoperative care are essential. A list of check lists and postoperative care is provided in the Appendix which can obviate and preempt most laser-induced complications. The consent form provided in the Appendix takes into account most of the legal possibilities and help to negate any medicolegal issues, if they do happen.

Bibliography 1. Bernstein EF. Laser treatment of tattoos. Clin Dermatol. 2006;24:43-55. 2. Graber EM, Tanzi EL, Alster TS. Side effects and complications of fractional laser photothermolysis: Experience with 961 treatments. Dermatol Surg; 2008.

470  Lasers in Dermatological Practice 3. Lapidoth M, Shafirstein G, Ben Amitai D, et al. Reticulate erythema following diode laser-assisted hair removal: a new side effect of a common procedure. J Am Acad Dermatol. 2004;51:774-7. Mar;34(3):301-5; discussion 305-7. 4. Mysore V, Anitha B, Hosthota A. Successful treatment of laser induced hypopigmentation with narrowband ultraviolet B targeted phototherapy. J Cutan Aesthet Surg. 2013 Apr;6(2):117-9. 5. Sardana K, Manjhi M, Garg VK, Sagar V. Which type of atrophic acne scar (Ice-pick, Boxcar, or Rolling) responds to nonablative fractional laser therapy? Dermatol Surg. 2014 Mar;40(3):288-300. 6. Vaiyavatjamai P, Wattanakrai P. Side effects and complications of fractional 1550-nm erbium fiber laser treatment among Asians. J Cosmet Dermatol. 2011 Dec;10(4):313-6. 7. West TB, Alster TS. Effect of pretreatment on the incidence of hyperpigmentation following cutaneous CO2 laser resurfacing. Dermatol Surg. 1999;25:15-7. 8. Zelickson Z, Schram S, Zelickson B. Complications in Cosmetic Laser Surgery: A review of 494 food and drug administration manufacturer and user facility device experience reports. Dermatol Surg. 2014;1–5. DOI: 10.1111/dsu.12461.

Chapter

18

New Aspects and Controversies in Lasers Kabir Sardana, Rashmi Sarkar

Introduction Lasers and their applications have over the years gone beyond the simple application of the principles of selective photothemolysis to novel procedures and indications to technology modifications. Combinations of lasers, especially fractional lasers, have resulted in endless possibilities that defy any meaningful discussion. Unlike drugs where restrictions exist, with lasers there is little regulation on approaches to therapy. Moreover, little evidence-based literature exists, possibly as very few objective tools are used for evaluation. Then there is the issue of results on Western skin, southeast Asian skin and Indian skin. We feel that not all results are replicable in our skin types. An assessment of literature is important to apply the knowledge in clinical practise. Not all studies are applicable to pigmented skin and as the laser technology has little regulation, it is important to decide how to assess clinical data. I have used 4 criteria to assess the studies published, these include as follows: 1. Deriving from the Cochrane data base criterion a prospective, split lesion or split face study has probably the maximum impact. If randomized its probably worth a read! 2. The technology used is as good as its assessment. Subjective percentile scoring systems and MASI are of little clinical use. An acne scar improvement of 75% has little meaning unless we qualify the type of scar improved. Similarly, a MASI improvement of say 40% is of little practical utility. Also this author is wary of combination studies. Hence, the use of peels or TC creams with lasers for melasma, has little value as probably the adjunct has done most of the work ! 3. In drug trials a “bioequivalence” with the comparator is important. Thus, a laser should be compared with the gold standard therapy. Thus, cellulite removal is of no use if not compared with surgery; similarly, melasma should be compared with TC creams and RF with surgical methods for skin tightening. Even if not formally compared the reader must sit back and reflect on just what the laser will achieve

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over conventional modalities. One important study is histological depth studies for fractional lasers, which is useful to titrate doses for optimal depth and are usually the most important studies with the maximum citations, but rarely asked for while buying the laser ! 4. The most important aspect to look for is follow up ! A short-term result with most nonablative lasers and skin tightening device may not persist! Conversely, acne scar improvement should be assessed at least 6 months after the last session. Melasma studies never look at follow-up as the lesion recur rapidly. Conversely, even though lentigines and PWS recur, there is no alternative so laser probably is the only option. Thus, our choice of studies discussed below reflect the above selection criterion. Thus, while a large number of excellent studies are published in the 4 leading journals on lasers every year their non-inclusion certainly does not reflect on the credibility of their data, but the selection criteria that we have used in the chapter.

LASERS FOR PIGMENTED LESIONS Are We Near a Perfect Method for Tattoo Removal? Tatoo removal requires a lot more than a perfectly aligned laser with an appropriate pulse duration. Even if a laser surgeon has a Qsw Nd:YAG,Qsw Ruby and Qsw Alex laser, to tackle all types of tattoos, results are often slow and incomplete.This is as, its often not understood,that the host factor is crucial in removing the destroyed pigment.But almost no study looks at this factor. Newer techniques of laser responsive tattoos may help, but with little regulation on the tattoo artists this is not about to happen in a hurry. Histological assessment is rarely done and can help in many ways, including locating fibrosis, tissue depth, granulomatous, and pseudolymphomatous reactions, which can help rationalize the clinical response. Besides the QS lasers, which offer a pulse duration already in the nanosecond range (10–9 seconds), newer laser technologies have shortened that pulse time to picoseconds (10–12 seconds), promising more effective results in tattoo removal. Recent published studies already confirm the effectiveness of shorter pulse lengths in the treatment of tattoos with safety equivalent to that of Qs lasers (Saedi N). Brauer et al. described the successful and rapid treatment of 12 tattoos containing blue and/or green pigment with the novel, picosecond, 755 nm alexandrite laser in men. The research group demonstrated at least 75% clearance of blue and green pigment after 1 or 2 treatments,with more than two-thirds of these tattoos approaching 100% clearance. Though a novel “rediscovery” it would entail a complete overhaul of the tools and incur a cost in procuring this tool for each coloured tattoo! Unless of course some company invents a picoseconds probe to attach on to the existing platforms. In addition to trials on the treatment of tattoos, studies

New Aspects and Controversies in Lasers  473

investigating the picosecond 755 nm alexandrite laser (Cynosure) on facial scarring and striae using a defractive lens show promising results (Brauer, 2013). Additional studies are underway for its use in melasma. In the future, additional wavelengths delivering picosecond pulse durations will aid in more effectively treating red-colored tattoos. A novel approach could address the issue of emergent removal of tattoos, as is the case in jobs and recruitment. A method of fine ablation of the epidermis followed by Qsw Nd:YAG has been found to reduce the sessions required, with similar results as are achieved with conventional lasers (Sardana K, 2013). We are now fine tuning the procedure for better cosmesis using the Er:YAG laser. Studies have shown that absorption and the strong scattering of epidermal and dermal tissue significantly reduce the depth of light penetration and laser energy that may reach the dermal tattoo pigment. This becomes even more evident when treating red, orange, or yellow pigmented tattoos. These inks tend to consist of pigments that need shorter wavelength lasers, such as the 532 nm Qs Nd:YAG, whose effectiveness is limited by skin scattering and hemoglobin absorption. However, by temporary reduction of the scattering coefficient of intervening skin layers, increased laser energy and shorter waveength light may be transmitted more efficiently to the tattoo ink particles in the skin. Therefore, optical-clearing techniques, with substances like glycerol, dimethylsulfoxide, and glucose have been shown to significantly reduce dermal scatter in animal models (Yoon J). A recent study used a glass microscope slide on the treatment area with a firm pressure to compress the skin which results in evacuating the blood from the capillary plexus and found this technique to be useful in tattoo removal (Murphy MJ). The old idea of the R20R method should not be the standard employed as after the first impact. The tattoo pigment is shattered and will have an altered optical property and size which will change the optical absorption. Moreover, the thermal injury released after even one impact in pigmented skin, can cause dyspigmentation, due to the photothermal effect of the Q-switched lasers. Because tattoo ink fades with each treatment, increasing fluences are necessary to achieve optimal tattoo removal with each subsequent treatment. If too high a fluence is used, especially with the initial treatments when the tattoo is darkest, injury to the skin with scarring can occur. Thus, it is advisable to increase the diameter of the probe instead of increasing the fluence, which is usually 4 mm in most devices. A recent study (Bernstein EF) found that with a novel dynamic system, with the ‘MAX-ON’ setting the fluence and diameter were adjusted dynamically so that the size of the spot became progressively smaller as the fluence is increased with each treatment. For example, the diameter of the treatment beam using the MAX-ON setting with a fluence of 4.2J/cm2 is 6.2 mm, decreasing to 5.2 mm at 6J/cm2, to 4.2 mm at 9.2J/cm2, and 3.7 mm at 12J/cm2. This achieved superior results as compared to the conventional probe used.

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Nevus of Ota The most interesting development in this dermal disorder is an understanding that the condition may have different color hues corresponding to various size of dermal melanocytosis. Thus, various laser wavelengths may be needed to treat the disorder effectively. The use of Qsw ND:YAG lasers for all types of lesions, with their variable response, is easily explained by this new study which begins to explain why not all lesions respond (Felton et al.). In 20% of patients, Qs-1,064 nm was most efficacious with 97% mean improvement. The mean improvement was 80% for those in whom Qs–755 nm was superior, and 90% for Qs–532 nm. Number of treatments required varied significantly according to lesional color and site: gray lesions and those on the forehead/ temple were most resistant. More such studies can shed light on the appropriate mix and match of lasers for this difficult problem, instead of using fractional lasers, which has a marginal effect in dermal pigmentation disorders.

Melasma Do We Finally Have Laser Treatments That Truly Work? The ever growing ‘successful’ therapies for a condition that tends to recur rapidly, makes it difficult to justify lasers for melasma. In fact the multitude of therapies is akin to the story of “the blind men and the elephant”. Each man is partly right since they have made contact with one major part of the whole. However, they are all wrong because in their blindness, they failed to comprehend the creature in its entirety! This aptly describes the multitudes of therapy for melasma and the devotion of researchers to their tool! Almost every laser, Er:YAG,Qsw lasers, fractional lasers and the new addition thullium laser, have been tried for melasma. And the reality is that unlike the “blind men” in the aforesaid story, all clinicians know that almost nothing consistently works except TC creams. Thus, it is best not to attempt to intervene specially with lasers, as it has been seen that in pigmented skins the lesion can even worsen, if an improper dose setting is employed. A recent study examined the 1,927-nm wavelength for melasma in a Asian population with primarily photodamage skin. (Lee HM). Four participants (16%) showed greater than 50% improvement, 14 (56%) showed 11–50% improvement, and seven (12%) showed 10% or less improvement. Interestingly, while some of us are enthusiastic about laser toning, other authors have moved beyond it to more safer tools. In fact, we had in a previous letter (Sardana K ) pointed out that the Qsw Nd:YAG, laser toning method can provoke mechanical shockwaves and lead to side effects with both hyperpigmentation and punctuate leukoderma. A recent study by Chung JY, et al. looks at a new type of intense pulsed light IPL with pulse–in–pulse (PIP) mode (multiple fractionated subpulses in one pulse width). This aims at a

New Aspects and Controversies in Lasers  475

gentler treatment as PIP IPL was designed to overcome the limitation of lowfluence IPL. PIP IPL emits the same wavelength as other conventional IPL devices. Instead of lowering applied fluence, it fractionates a pulse duration of 10 ms into 100 subpulses in which the pulse width of one subpulse is 40 µs. Through these fractionated pulses, PIP IPL (E-toning, UnionMedical Co., Seoul, Korea) can achieve gentle removal of unwanted pigmentation without aggravation or flare up of melasma. A 54.4% improvement in MASI was seen on the PIP IPL, which incidentally in Korean skin is good but probably not in Indian skin types. Thus, while studies will keep getting published on melasma, two important issues should always be answered, firstly how does it compare with conventional therapies and what is the relapse rate. on follow up ? If a method is able to achieve results better than TC creams on these two parameters it is definitely worth a look !

Bibliography 1. Brauer JA, Reddy KK, Anolik R, et al. Successfuland rapid treatment of blue and green tattoo pigment with a novel picosecond laser. Arch Dermatol 2012;148: 820-3. 2. Brauer J, Correa L, Bernstein L, et al. We’re not stretching the truth: treatment of striae with a picosecond 755 nm alexandrite laser and defractive lens array. Abstract presented at American Society for Laser Medicine and Surgery Conference. Boston, April 2013;1-6. 3. Bernstein EF, Civiok JM. A continuously variable beam-diameter, high-fluence, Q-switched Nd:YAG laser for tattoo removal: Comparison of the maximum beam diameter to a standard 4-mm-diameter treatment beam. Lasers Surg Med. 2013;45(10):621-7. 4. Felton SJ, Al-Niaimi F, Ferguson JE, Madan V. Our perspective of the treatment of naevus of Ota with 1,064-, 755- and 532-nm wavelength lasers. Lasers Med Sci. 2013;May 4. 5. Hutton Carlsen K, Tolstrup J, Serup J. High-frequency ultrasound imaging of tattoo reactions with histopathology as a comparative method. Introduction of preoperative ultrasound diagnostics as a guide to therapeutic intervention. Skin Res Technol. 2013;Sep 7. 6. Lee HM, Haw S, Kim JK, Chang SE, Lee MW. A split-face study using 1,927 nm Thulium fiber fractional laser for photoaging and melasma in Asian skin. Dermatol Surg. 2013;39:879-88. 7. Luebberding S, Alexiades-Armenakas M. New tattoo approaches in dermatology. Dermatol Clin. 2014;32(1):91-6. doi: 8. Marcus L. Treatment of hyperpigmentation-melasma with photodynamic therapy. J Drugs Dermatol. 2006;5(2 Suppl):9-11. 9. Murphy MJ. A novel, simple and efficacious technique for tattoo removal resulting in less pain using the Q-switched Nd:YAG laser. Lasers Med Sci. 2014; Mar 2. 10. Sardana K, Garg VK, Bansal S, Goel K. A promising split-lesion technique for rapid tattoo removal using a novel sequential approach of a single sitting

476  Lasers in Dermatological Practice of pulsed CO(2) followed by Q-switched Nd: YAG laser (1064 nm). J Cosmet Dermatol. 2013;12(4):296-305. 11. Sardana K, Chugh S, Garg VK. Which therapy works for melasma in pigmented skin: lasers, peels, or triple combination creams? Indian J Dermatol Venereol Leprol. 2013;79(3):420-2. 12. Saedi N, Metelitsa A, Petrell K, Arndt KA, Dover JS. Treatment of tattoos with a picosecond alexandrite laser: a prospective trial. Arch Dermatol. 2012;148(12): 1360-3. 13. Yoon J, Son T, Jung B. Quantitative analysis method to evaluate optical clearing effect of skin using a hyperosmotic chemical agent. Conf Proc IEEE Eng Med Biol Soc. 2007;2007:3347–9.

FRACTIONAL LASERS This is the most talked about technology and we daresay except for some indications like, ,acne scars, post- traumatic scars, and photodamage, it may be highly overrated. There are so many issues that have to be understood before their rampant application, that it is the brave surgeon who ventures to proclaim where this technology does not work !

Histological Depth Most FDA approved lasers have to submit in vitro data regarding the depth of penetration,which is the most crucial aspect specially in treating acne scars. This is as if the laser MTZ does not reach the depth of the ice pick scar, which is the deepest of the acne scars, little clinical effect is seen. This is complicated further by the actual in vivo dynamics of the lasers. This is rarely the topic of research and is a data that should be elicited from the laser company at the outset, much before the costing is decided. As it is not always possible to perform a histology, computer simulation models have been devised which can have great practical value. Marqa MF et al. have shown that a computer simulation model used for ablative FP and non-ablative FP treatment was usually deeper (21 ± 2%) and wider (12 ± 2%) when compared with histological analysis data. Thus, factoring for these changes, which is likely due to shrinkage effect of excision of cutaneous tissues, a good correlation can be established between the  simulation  and the histological analysis results. Studies on individual technologies can help the clinician arrive at a reasonable dose and depth analysis to plan treatment sessions without having to do an actual histological study.

Aspect Ratio and Depth The aspect ratio is simple put the “volume” of the tissue impacted and depends on the length and width of the laser beam (MTZ). This, in turn, is affected by various factors, including the,dose, pulse duration, density, temperature, skin hydration and extensibility. It is surprising how laser surgeons use preset

New Aspects and Controversies in Lasers  477

settings, and report subjective (VAS based) scoring improvements, which in some cases mask the actual results. For many indications, data on aspect ratios should be elicited to make the laser intervention meaningful. This again is readily available from most FDA approved laser manufactures.

Acne Scars The use of numerous combinations and techniques have rarely focussed on two prerequisites for results.The first is an objective assessment of scar depth. This requires a 3 dimensional tool which can put the results into a realistic perspective.Secondly, there is a need to focus on which type of scar responds to fractional lasers. This is important as the deep ice pick scars rarely respond to most lasers. That brings us to another question, that is do all scars ever respond? Probably not, thus giving an assurance of complete response to a patient is inadvisable as scars have a “memory” which is not amenable to change by the most fractional laser. Our work(Sardana K ,2014) showed that the deeper icepickice pick scars do not respond to the fractional Er:Glass even though we changed the aspect ratio of the laser. Thus, probably it is time to evaluate scar improvement studies by looking for sub“scar type” improvement than a global assessment as ultimately with most lasers the deeper scars remain ! Fractional RF is a tool that has been occasionally been used in acne scars. A recent study by Dr Trelles used the Legato, a new bimodal system that combines two technologies—fractional ablative unipolar microplasma radiofrequency (RF) and acoustic pressure ultrasound (US)—to deliver drugs and bioactive compounds into the dermis.The Pixel RF generates microchannels and provoke thermal damage and fractional ablation. Each microchannel is on a average 80–120 µm in diameter and has a depth of 100–150 µm, depending on the RF power settings. After topical application of a special compounded preparation into the microchannels, the ultrasound generated by the ImpactTM module facilitates penetration into the dermis. The mode of operation is based on mechanical (acoustic) pressure and torques by propagation of the US wave via the sonotrode to the distal horn and the creation of a “hammering” effect. This extracts the liquid from within the microchannels and forces the bioactive compounds to be enhanced under the epidermis–dermis junction. A rapid improvement was seen in 2 months in facial acne scarring of about 56.7%, and it seems that radiofrequency, especially in combination with other methods, can achieve aesthetic results which are comparable to those achieved with ablative lasers. The study results depict a marked improvement in icepick scars which is interesting as the depth of the RF is probably not as deep as the other fractional devices. A study by Zhang Z et al. looks at microplasma RF where an array of closely applied microperforations in the skin are generated, which was found to be as effective as fractional CO2 laser.

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Is Nonablative Fractional Laser Inferior to Fractional Ablative Lasers ? Put simply, is fractional CO2 superior to say, Er:Glass. Such a question, totally ignores the indication and the parameters used. Using acne scars as the gold standard, there is enough evidence that there is little difference, if the appropriate parameters are selected. For other indications the differences are even less. Dr Manstein,who invented the technology has allured to this in his manuscript. Turning the tables, so as to speak, Er:Glass which has a less absorption capacity for water as compared to CO2 can produce more heat induced collagen remodelling and thus should be superior to fractional CO2! Thus, it is best to stick to any one technology then to run after the “new kid on the block”. The few studies on this topic have found a marginal difference in the various technologies and probably a more important question is when to intervene, thus earlier the better (Cho S, Cho SB). Taking the argument further there is little to choose over Fractional Er:YAG and fractional CO2 lasers as far as atrophic scars are concerned (Manuskiatti W). A more important question is why with both ablative and non ablative lasers, being part of all laser companies inventory, are more studies on this comparison rarely published. In our experience, this is as the results do not justify the campaigns to promote one technology over the other.

Complications of Fractional Lasers It has been our experience that the technology is safe with minimal side effects. When used according to accepted parameters, fractional CO2 laser resurfacing is a very safe procedure. The laser surgeon must have a thorough knowledge of the structure and physiology of skin. Early recognition, close monitoring, and careful wound care will prevent long-term sequelae when complications do occur. ( See Appendix Post operative care) In Asians, the main complication is post-inflammatory hyperpigmen­ tation (PIH) which is known to be related to the density and energy of the device used. An important issue is bulk tissue heating and while this has been frequently mentioned, variables affecting this have not been previously addressed. The degree of bulk tissue heating depends upon several factors including the rate of the energy delivered by the device, the rate of skin cooling and the rate of heat removal by blood flow.

Is Ultrapulse CO2 Better Than Superpulse CO2 This is definitely true for ablative lasers, but there is neither a study nor any logical reason to believe that the same principles works in fractional laser. Interestingly conferences abound in discussions on this and with very little histological data in public domain a fair assessment cannot be made. Xu XG et al. have looked at this aspect where they compared the UPCO2 mode (DeepFX microscanner handpiece of the fractional ultrapulsed

New Aspects and Controversies in Lasers  479

CO2 laser (Ultrapulse Encore; Lumenis Ltd, Santa Clara, CA), and the SPCO 2 mode (AcuPulse CO2 laser device with SurgiTouch Automation System; Lumenis Ltd). The parameters were set equally: pulse energy 15 mJ, density 5% (196 MTZ/cm2). Although the depths of ablation were slightly higher on the UPCO2 side (251.6 ± 10.8 lm) than on the SPCO2 side (245.1 ± 16.8 lm), the difference was not significant. Neither were the thermal damage depths or thermal coagulation zone widths. Though this study was done on the back of the patients which is not the ideal site for acne scars, it goes to prove that the “pulse” debate has little substance. Another study by the same group (Luo YJ) on the face in photodamage skin also found no difference. Thus on a purely theoretical level, the only difference may be that SPCO2 produces more collateral thermal effects because of the longer dwelling time.

Will Nonablative Rejuvenation Replace Ablative Lasers The word fractional lasers,refers to a “fraction or percentage “of the skin affected by a pass of the laser. This fact is enough to decry any dramatic results, as the results will still not match the efficacy of ablative lasers. Thus, ablative laser resurfacing still remains the gold standard for treating advanced and severe photoaging providing excellent results in experienced hands. Nonablative resurfacing is ideal for patients under the age of 50 years with minimal facial sagging, and for those who are unwilling to undergo expensive and demanding ablative procedures. But the use of any tool alone in facial rejuvenation is useless and an appropriate mix and match with fillers and botox is needed for any meaningful results.

Novel Wavelenghths 1565 nm A new NAFL with no disposable tips, with a handpiece that allows realtime “cool-scanning” in a stamping fashion, was recently approved by the Food and Drug Administration (FDA) (M22 [ResurFx module]; Lumenis, Inc, San Jose, CA, USA). This infrared laser energy at 1565 nm has a slightly lower absorption coefficient for water than that of 1550 nm (9/cm and 8/ cm, respectively), leading to marginally greater dermal penetration. A wide variety of shapes, densities, and sizes of patterns are offered, ranging from 5 to 18 mm. Energy level ranges from 10 to 70 mJ with density ranging from 50 to 500 spots/cm2. Preliminary results of a 2-center trial treating a total of 30 subjects with visible rhytides (Fitzpatrick Wrinkle Score of 3–6) and/or striae alba (present for >1 year), who received a single-pass treatment monthly for 3 consecutive treatments, shows appreciable results and high patient satisfaction (Jung JY).

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1940 nm Nonablative Fractionated Laser 1940 nm is a novel wavelength that has a higher absorption coefficient for water than other nonablative wavelengths (1410–1550 nm) and is weaker than ablative wavelengths. A new fractional 1940 nm laser comprises thulium rod pumped by a pulsed alexandrite laser. The fractional patterns are generated by 3 separate hand pieces (2 dot and 1 grid geometries) whereby a larger beam is broken up into smaller microbeams by a diffractive microlens system. Its depth of penetration extends approximately 200 µm deep. In a pilot trial of 11 patients with facial photodamage, rhytides were reduced by 15% and pigment improved by 30% (Ross et al.).

Bibliography 1. Chan HH, Manstein D, Yu CS, et al. The prevalence and risk factors of postinflammatory hyperpigmentation after fractional resurfacing in Asians. Laser Surg Med 2007;39:381-5. 2. Cho S, Jung JY, Shin JU, Lee JH. Non-Ablative 1550nm Erbium-Glass andAblative 10,600nm Carbon Dioxide Fractional Lasers for Various Types of Scars in Asian People: Evaluation of 100 Patients. Photomed Laser Surg. 2014;32(1):42-6. 3. Cho SB, Lee SJ, Cho S, Oh SH, Chung WS, Kang JM, Kim YK, Kim DH. Non-ablative 1550-nm erbium-glass and ablative 10 600-nm carbon dioxide fractional lasers for acne scars: a randomized split-face study with blinded response evaluation. J Eur Acad Dermatol Venereol. 2010;24(8):921-5. 4. Jung JY, Cho SB, Chung HJ, et al. Treatment of periorbital wrinkles with 1550- and 1565-nm Er:glass fractional photothermolysis lasers: a simultaneous split-face trial. J Eur Acad Dermatol Venereol. 2010;25:811-8. 5. Lipozencˇic´ J, Mokos ZB. Will nonablative rejuvenation replace ablative lasers?Facts and controversies. Clin Dermatol. 2013;31(6):718-24. 6. Luo YJ, Xu XG, Wu Y, Xu TH, Chen JZ, Gao XH, Chen HD, Li YH. Split-face comparison of ultrapulse-mode and superpulse-mode fractionated carbon dioxide lasers on photoaged skin. J Drugs Dermatol. 2012;11(11):1310-4. 7. Manuskiatti W, Iamphonrat T, Wanitphakdeedecha R, Eimpunth S. Comparison of fractional erbium-doped yttrium aluminum garnet and carbon dioxide lasers in resurfacing of atrophic acne scars in Asians. Dermatol Surg. 2013;39(1 Pt1):111-20. 8. Marqa MF, Mordon S. Laser fractional photothermolysis of the skin: Numerical simulation of microthermal zones. J Cosmet Laser Ther. 2014;16(2):57-65. 9. Ramsdell WM. Fractional CO2 Laser Resurfacing Complications. Semin Plast Surg 2012;26:137–140 10. Ross EV, Miller L, Mishra V, et al. Clinical evaluation of a non-ablative 1940-nm fractional laser. Abstract presented at American Society for Laser Medicine and Surgery Conference. Boston, 2013;4–6. 11. Sardana K, Manjhi M, Garg VK, Sagar V. Which Type of Atrophic Acne Scar (Icepick, Boxcar, or Rolling) Responds to Nonablative Fractional Laser Therapy? Dermatol Surg. 2014;40(3):288-300. 12. Trelles MA, Martínez-Carpio PA. Attenuation of acne scars using high power fractional ablative unipolar radiofrequency and ultrasound for transepidermal

New Aspects and Controversies in Lasers  481 delivery of bioactive compounds through microchannels. Lasers Surg Med. 2014;46(2):152-9. 13. Xu XG, Gao XH, Li YH, Chen HD. Ultrapulse-mode versus superpulsemode fractional carbon dioxide laser on normal back skin. Dermatol Surg. 2013;39(7):1047-55. 14. Zhang Z, Fei Y, Chen X, Lu W, et al. Comparison of a fractional micro-plasma radio-frequency technology and CO 2 fractional laser for the treatment of atrophic acne scars: a randomized split-face clinical study. Dermatol Surg 2013;39:559-66.

LASERS FOR SCARS Traumatic Surgical and Burn Scars: What Have We Learned? Cutaneous scars can be complex and thus the approach to therapy is often multimodal. Intralesional corticosteroids have long been a staple in the treatment of hypertrophic and restrictive scars. Recent reports suggest the fractional ablative zones may also be used in the immediate postoperative period to enhance delivery of drugs and other substances. Waibel JS showed that the use of topically applied triamcinolone acetonide suspension in the immediate postoperative period helps in better scar resolution. A recent consensus has concluded that ablative fractional  resurfacing, deserves a prominent role in future scar treatment paradigms. But more crucial is when and how early can an intervention be employed.With very little data on record, it remains to be seen, how much the technology can fulfill the needs of the clinician. There is some proof though that the fractional Er:YAG is inferior as compared to the fractional CO2 in this regard. Importantly, consensus guidelines may not apply to all scenarios and continents, specially if other nonlaser interventions have been tried already. Thus, a patient who has already tried conventional therapy may not benefit much from fractional lasers.

Striae Distensae Striae distensae (SD) represent a common disfiguring cutaneous condition characterized by linear reddish smooth bands of atrophic-appearing skin. Novel approaches include treatments with various types of lasers with the flashlamp-pumped pulsed dye laser (PDL; 585 nm) being the most commonly reported. Though fractional photothermolysis has been tried one must understand that interventions depend on the stage of the striae. Early “striae rubra” may not require any intervention while for the late stages “striae alba” lasers may be tried. Dr Gauglitz GG in a study from Germany compared ablative Erbium:YAG fractional laser with 585 nm PDL and found the former to be a better tool for striae.

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Fractional lasers have been used as a method of drug delivery. Issa MC et al. evaluated the efficacy and safety as well as patient’s satisfaction using ablative fractional RF with retinoic acid 0.05% cream and an acoustic pressure wave ultrasound (US) in patients with alba-type SD on the breast and found it safe and effective.

Bibliography 1. Anderson RR, Donelan MB, Hivnor C, Greeson E, Ross EV, Shumaker PR, Uebelhoer NS, Waibel JS. Laser Treatment of Traumatic Scars With an Emphasis on Ablative Fractional Laser Resurfacing: Consensus Report. JAMA Dermatol. 2013 Dec 11. doi: 10.1001/jamadermatol.2013.7761. 2. Choi JE, Oh GN, Kim JY, Seo SH, Ahn HH, Kye YC. Ablative fractional laser treatment for hypertrophic scars: comparison between Er:YAG and CO2 fractional lasers. J Dermatolog Treat. 2014;25(4):299-303. 3. Gauglitz GG, Reinholz M, Kaudewitz P, Schauber J, Ruzicka T. Treatment ofstriae distensae using an ablative Erbium: YAG fractional laser versus a 585-nm pulseddye laser. J Cosmet Laser Ther. 2013 Nov 18. 4. Issa MC, de Britto Pereira Kassuga LE, Chevrand NS, do Nascimento Barbosa L,Luiz RR, Pantaleão L, Vilar EG, Rochael MC. Transepidermal retinoic acid delivery using ablative fractional radiofrequency associated with acoustic pressure ultrasound for stretch marks treatment. Lasers Surg Med. 2013;45(2): 81-8. 5. Waibel JS, Wulkan AJ, Shumaker PR. Treatment of hypertrophic scars using laser and laser assisted corticosteroid delivery. Lasers Surg Med. 2013;45(3):135-40.

LASERS FOR HAIR REMOVAL Studies comparing lasers are company driven, and it is expected that studies comparing the “in motion’’ technology and the conventional diode lasers will increasingly be published. Though initial studies did not find any advantage of the “in motion “technology, a recent study by Koo B et al. has reignited the debate. Though high powered diode lasers have traditionally been used they can have potential side effects, and thus, an attempt is made at lowering the energy which should result in less pain and fewer potential adverse events, but this could theoretically affect the efficacy of the therapy. The “in motion” low-energy, high-repetition diode laser pulses of Soprano XL in SHR mode ensures epidermal cooling and aims at raising the temperature of the subdermal layer of the skin progressively to at least to 45°C, less than the thermal destruction temperature of the hair follicle without heating the epidermis of the skin region. With this technique, the laser handpiece never remains stationary in one spot, but is always moving in the treatment area, thus the skin is never subjected to a single diode laser pulse greater than 10 J/cm2. Since this is below the threshold of burning, the incidence of adverse effects is lower making it more acceptable.

New Aspects and Controversies in Lasers  483

Bonnie Koo in a prospective, randomized, side-by-side comparison of either the legs or axillae compared the Soprano XL 810 nm diode in super hair removal (SHR) mode (Alma Lasers, Buffalo Grove, IL) hereafter known as the “in-motion” device vs. the LightSheer Duet 810 nm diode laser (Lumenis) hereafter known as the “single pass” device. Five laser treatments were performed 6–8 weeks apart with 1, 6, and 12 months follow-ups for hair counts. Pain was assessed in a subjective manner by the patients on a 10-point grading scale. Hair count analysis was performed in a blinded fashion. There was a 33.5% and 40.7% reduction in hair counts at 6 months for the single pass and in-motion devices, respectively. The average pain rating for the single pass treatment was significantly greater than the in-motion treatment Garden JM, et al. in a recent study have evaluated a home hair removal device using combined radiofrequency (RF) and intense pulsed light (IPL) energy for effectiveness and safety with all skin types (I–VI). For the first time, a home hair removal device has been shown to be effective and safe in all skin types using a low–energy RF–IPL device. This has wide reaching implications as a 55% reduction was achieved after 7 sessions which is possibly as the dose used was conservative. Probably tweaking of the dose would lead to better results. Further advances in this may make laser centers redundant but would also lead to more side effects!

Bibliography 1. Bonnie Koo, Kaity Ball, Anne-Marie Tremaine and Christopher B. Zachary. A comparison of two 810 diode lasers for hair removal: Low fluence, multiple pass versus a high fluence, single pass technique. Lasers in Surgery and Medicine. 2014; Febuary 7. 2. Garden JM, Zelickson B, Gold MH, Friedman D, Kutscher TD, Afsahi V. Home hair removal in all skin types with a combined radiofrequency and optical energy source device. Dermatol Surg. 2014;40(2):142-51.

LASERS FOR VASCULAR INDICATIONS The response of port-wine stains (PWS) to conventional laser treatment in adults is difficult to predict. An interesting study by Bencini PL assessed the influence of local or systemic hemodynamic variables on the clearance of PWS by using flash lamp-pumped pulsed (FLPP) dye laser. Clearance was achieved in 50.1% of patients after a maximum of 15 treatment sessions. Reduced response was associated with, increased age, a newly described type III capillaroscopic pattern, and presence of lesions in dermatome V2. Also arterial hypertension was also associated with a lower clinical response. Thus, the authors concluded that age, arterial hypertension, capillaroscopic pattern, and body location should be considered when planning laser treatment of PWS.

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Fractional lasers have been used as a method for drug delivery. A recent study by Ma G et al. in nine patients (1–6  months) where therapy with the DeepFx mode (25-30 mJ/pulse, 5% density, single pulse) at 1 week interval was followed by application of  timolol maleate 0.5% ophthalmic solution which was applied under occlusion for 30  minutes four to five times per day for an average  treatment  duration of 14.2  weeks.   Four patients (44.4%) demonstrated excellent regression, and four (44.4%) showed good response. One of the issues regarding this is the tolerance of fractional lasers in children, which may be a hindrance to the wide spread use of this combination.

Bibliography 1. Bencini PL, Cazzaniga S, Galimberti MG, Zane C, Naldi L. Variables affecting clinical response to treatment of facial port-wine stains by flash lamp-pumped pulsed dye laser: the importance of looking beyond the skin. Lasers Med Sci. 2014;Feb 1. 2. Ma G, Wu P, Lin X, Chen H, Hu X, Jin Y, Qiu Y. Fractional Carbon Dioxide LaserAssisted Drug Delivery of Topical Timolol Solution for the Treatment of Deep Infantile Hemangioma: A Pilot Study. Pediatr Dermatol. 2014 Mar 6. doi:10.1111/ pde.12299

NONSURGICAL SCULPTING Body-sculpting and fat-removal procedures are becoming increasingly more popular. Although diet, exercise, and bariatric surgery may be effective in controlling obesity, cosmetic procedures may still be necessary to remove localized adiposity in difficult to locations, such as the flanks and abdomen. Liposuction is the most frequently used method for excess local fat removal, but it is considered to be an invasive surgical procedure with significant risks, including pain, infection, prolonged recovery, scarring, hematoma, deep vein thrombosis/ pulmonary embolism, and anesthesia-related complications. These risks and associated downtime have led patients to seek out alternatives, such as noninvasive body contouring. Currently available noninvasive fat removal methods include low-level laser therapy, radiofrequency, ultrasound, infrared light, and cryolipolysis An extensive elucidation of conventional modalities like RF and focused ultrasound applications is detailed in chapter 10 Cryolipolysis (CoolSculpting, Zeltiq, Pleasanton, CA) is a novel method of selective removal of fat with cooling. This technique is based on the concept that fat cells are more sensitive to cold than the surrounding tissue. Prior studies and observations have demonstrated that cold exposure can induce selective damage to the subcutaneous fat via induction of panniculitis, resulting in reduction in the superficial fat layer of the skin. Dr Lilit Garibyan have published a study where volume changes and quantification after noninvasive fat removal in comparison to an internal control were done

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using 3D photography and reported about 39.6 cc of fat loss of the treated flank at 2 months after a single treatment cycle. Cellulite affects 95% of women and is often treated by various means. Acoustic wave therapy (AWT) using extracorporeal pulse activation technology (EPAT) can also be used to manage cellulite (Adatto M). The difference between treated and untreated legs was statistically significant with regard to depressions, elevations, roughness and elasticity after the first follow-up visit. Thus, this may be a safe and effective treatment alternative for the temporary improvement in the appearance of cellulite.

Bibliography 1. Adatto M, Adatto-Neilson R, Servant JJ, Vester J, Novak P, Krotz A. Controlled, randomized study evaluating the effects of treating cellulite withAWT/EPAT. J Cosmet Laser Ther. 2010;12(4):176-82. 2. Coleman KM1, Coleman WP 3rd, Benchetrit A. Non-invasive, external ultrasonic lipolysis. Semin Cutan Med Surg. 2009;28(4):263-7. 3. Fatemi A. High-Intensity Focused Ultrasound Effectively Reduces Adipose Tissue. Semin Cutan Med Surg. 2009;28:257-62. 4. Garibyan L, Sipprell WH 3rd, Jalian HR, Sakamoto FH, Avram M, Anderson RR. Three-dimensional volumetric quantification of fat loss following cryolipolysis. Lasers Surg Med. 2014;46(2):75-80. 5. Jewell ML, Baxter RA, Cox SE, Donofrio LM, Dover JS, Glogau RG, Kane MA, Weiss RA, Martin P, Schlessinger J. Randomized sham-controlled trial to evaluate the safety and effectiveness of a high-intensity focused ultrasound device for noninvasive body sculpting. Plast Reconstr Surg. 2011;128(1):253-62. 6. Sadick N. Thermage Radiofrequency for Noninvasive and Nonablative Body Contouring Cosmetic Dermatology, 2010;23(12):555-560 7. Sasaki GH, Tevez A. Clinical efficacy and safety of focused-image ultrasonography: A 2-year experience. Aesthet Surg J. 2012;32:601-12. 8. Sasaki GH, Tevez A. Microfocused Ultrasound for Nonablative Skin and Subdermal Tightening to the Periorbitum and Body Sites: Preliminary Report on Eighty-Two Patients. Journal of Cosmetics, Dermatological Sciences and Applications. 2012;2:108-16.

Microfocused Ultrasound With Visualization Acne Although the mechanism of action remains unclear, it is hypothesized that with the use of 1.5 mm and 1 mm depth probes, focal thermal coagulation points are delivered into sebaceous glands, rendering them in active. In a pilot study in which 10 subjects received 3 treatments, 14 days apart with MFU-V, a significant decrease in sebum, as measured by a sebumeter (CourageKhazaka, Cologne, Germany), was noted over the forehead, cheeks, and chin 60 days after treatment. Eighty percent of the subjects had a decrease in total acne lesion count at 60 days, and 100% of subjects showed a decrease at 180 days after the last treatment.

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Probably the future may hold a promise for treating moderate-to-severe inflammatory acne.

Bibliography 1. Munavalli G. Single-center, prospective study on the efficacy and safety of microfocused ultrasound with visualization for the noninvasive treatment of moderate-to-severe facial acne. Abstract presented at American Society for Laser Medicine and Surgery Conference. Boston, April. 2013:4-6.

NOVEL WAVELENGTHS Sebaceous Glands Sakamoto et al. have looked at wavelengths that target sebaceous glands and narrowed down the search to 1210, 1728, 1760, 2306 and 2346 nm. Laserinduced heating at 1710 and 1720 nm was about 1.5-fold higher in human sebaceous glands than in water. With the use of wavelengths that more specifically target sebum, the investigators hypothesized that SP of sebaceous glands, another part of hair follicles, may equate to the success of permanent hair removal. In a pilot clinical study to evaluate the efficacy of a novel 1720 nm laser in the treatment of sebaceous hyperplasia, 4 patients underwent a test spot, followed by 2 full treatment sessions using the 1720 nm laser (Del Mar Medical Technologies, Del Mar, CA, USA). A 400 mm fiber, with a mean fluence of 45 J/cm2, spot size of 750 mm, and pulse duration of 50 milliseconds was used. The desired end point was a change from pretreatment granular yellow appear­ance to a creamy-white smooth surface. Many of the lesions resolved almost completely after a single treatment, and no additional treatment was required. Thus, the future may hold a hope for treatment of sebaceous hyperplasia, ectopic sebaceous glands, acne vulgaris, and laser hair removal, with this wave length.

Wavelength 1210 nm Absorption peaks near 915, 1210, 1400, 1720, and 2346 nm have been demonstrated for lipids. A study to evaluate the histologic changes over time of a novel noninvasive treatment with a 1210 nm laser with surface cooling, to more selectively target fat, was performed on 8 patients before abdominoplasty. The investigators concluded that significant zones of fat reduction in hypodermal necrosis could be achieved, while including or avoiding damage to the lower dermis depending on the settings used. Clearance of the damaged adipocytes proved slow, with residual damage still present at 6 months (Echague AV). A clinical trial was performed to evaluate the use of the 1210-nm wavelength (ORlight, Potters Bar, UK) for fat preservation (Centurion P

New Aspects and Controversies in Lasers  487

et al). This was a concept known as selective potothermostimulation (PSP), a concept whereby the wavelength has the ability to stimulate adipocytes and mesenchymal cells of the subcutaneous tissue. One hundred two patients were treated with the 1210-nm diode laser and followed. Histologic analyses revealed a 98% preservation of aspirated adipocytes. The investigators hypothesize that this selective PSP and preservation of the integrity of adipocytes makes this laser wavelength ideal when performing laser-assisted liposculpture followed by fat grafting or breast reconstruction. There may be a potential use of this laser for laser-assisted lipoplasty and, perhaps, the removal of large lipomas.

Bibliography 1. Centurion P, Noriega A. Fat preserving by laser 1210-nm. J Cosmet Laser Ther. 2013;15(1):2-12. 2. Echague AV, Casas G, Rivera FP, et al. Over time histological tissue changes after non-invasive treatment with a 1210 nm laser. Abstract presented at American Society for Laser Medicine and Surgery Conference. Boston, April 2013;4-6. 3. Sakamoto FH, Doukas AG, Farinelli WA, et al. Selective photothermolysis to target sebaceous glands: Theoretical estimation of parameters and preliminary results using a free electron laser. Lasers Surg Med. 2012;44(2):175-83. 4. Winstanley D, Blalock T, Houghton N, et al. Treatment of sebaceous hyperplasia with a novel 1,720 nm laser. J Drugs Dermatol. 2012;11(11):1323-6.

Laser Treatment for Axillary Hyperhidrosis There are few isolated retrospective and case studies reporting the use of Nd:YAG lasers subdermally in the treatment of hyperhidrosis. Most recently, Yanes presented results on the use of the 924/927 nm diode laser subdermally,via a 1.5-mm diameter flexible fiber, to selectively destroy axillary sweat glands before aspiration and curettage. Although microwaves are not commonly used in cutaneous surgery, they are able to focus heat at the interface between the skin and subcutaneous tissue, causing irreversible thermal necrosis of both apocrine and eccrine glands. In 2011 a microwave device was approved by the FDA for the treatment of primary axillary hyperhidrosis (Johnson et al.). MFU-V has been investigated for the treatment of axillary hyperhidrosis. In a randomized, double-blind controlled trial, 12 of 20 hyperhidrotic adults with Hyperhidrosis Disease Severity Scale scores of 3 or 4 underwent 2 treatments, 30 days apart. The sham group (8 of 20) received treatment with the energy turned to 0 J. Patients were followed for 4 months, and a response rate of 67% to 83% ( P < 0.005) was seen across all post-treatment time points for the active group, versus 0% for the sham group (Nestor M). The use of a novel microwave energy device that destroys eccrine glands at the interface of the deep dermis and subcutis, minimizing damage to

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surrounding tissue has been used for axillary hyperhidrosis (Hong HC). An earlier-generation device was reported to be efficacious and safe in a randomized, blinded, multicenter study. Glaser DA in a RCT studied a similar device and found that thirty days after treatment, the active group had a responder rate of 89% (72/81), and the sham group had a responder rate of 54% (21/39) (P < 001). Treatment efficacy was stable from 3 months (74%) to 12 months (69%), when follow-up ended. Adverse events were generally mild, and all but one resolved over time. This US FDA approved device may provide a simple treatment for this distressing disorder

Bibliography 1. Glaser DA, Coleman WP 3rd, Fan LK, et al. A randomized, blinded clinical evaluation of a novel microwave device for treating axillary hyperhidrosis: the dermatologic reduction in underarm perspiration study. Dermatol Surg. 2012;38(2):185-91. 2. Jacob C. Treatment of hyperhidrosis with microwave technology. Semin Cutan Med Surg. 2013;32(1):2-8. 3. Johnson JE, O’Shaughnessy KF, Kim S. Microwave thermolysis of sweat glands. Lasers Surg Med. 2012;44(1):20-5. 4. Johnson JE, O’Shaughnessy KF, Kim S. Microwave thermolysis of sweat glands. Lasers Surg Med. 2012;44(1):20-5. 5. Nestor M, Hyunhee P. Randomized, double-blind, controlled pilot study of the efficacy and safety of micro-focused ultrasound for the treatment of axillary hyperhidrosis. Abstract presented at American Society for Laser Medicine and Surgery. 6. Yanes FD. G: laser-assisted minimally invasive surgery for primary hyperhidrosis. Abstract presented at American Society for Laser Medicine and Surgery Conference. Boston, April 2013; 4-6.

HOME USE DEVICES Over the past several years, several home-based cosmetic devices have been introduced in the market. These miniaturized devices are designed to address a variety of indications, including photorejuvenation, acne, hair growth, and hair removal. They are underpowered yet have specific safety features to ensure that “nonprofessional” operators can use them with ease.

Fractional Devices One of the first fractional, photorejuvenation devices to be launched was the PaloVia Skin renewing Laser (Palomar Medical Technologies, Burlington, MA, USA). This hand-held, nonablative diode laser (1410 nm, 15 mJ, 10  millisecond pulse duration) has been cleared by the FDA for reduction of fine lines and wrinkles around the eyes. Another home-based, fractional diode device (1435 nm, 1.2 W) is the Philips Reaura (Philips, Amsterdam, the

New Aspects and Controversies in Lasers  489

Netherlands), with initial studies claiming rejuvenation effects in 8 weeks following twice-weekly application. In addition, new in-home radiofrequency devices have been developed and are presently being investigated for their effects on photorejuvenation. More recently, a prototype in-home NAFL device for the treatment of solar lentigines has been developed (Laserscript; Palomar Medical). This 1410 nm, nonablative diode was used to treat 33 patients in a pilot trial in which subjects treated themselves with energies up to 30 mJ per microbeam for 4 weeks, and were followed for 3 months (Weiss R).

Hair Growth Devices Home-based hair growth devices, such as the HairMax LaserComb (Lexington International, LLC, Boca Raton, FL, USA), Laser Cap (Transdermal Cap, Inc, Gates Mills, OH, USA), and TOPHAT655 device (Apira Science, Inc, Newport,CA, USA) incorporate a low-level light therapy concept also found in their in-office counterparts. These hair-growth devices contain low-powered laser diodes with wavelengths in the region of 630–670 nm, and are thought to induce proliferative activity in hair follicles resulting in terminalisation of vellus human hair follicles. In a double-blind, randomized controlled trial of 41 males, the laser group received 25-minute treatments in a bicyclehelmetlike apparatus (TOPHAT655) every other day for 16 weeks. When hair counts at 16 weeks were compared with baseline counts, a 39% increase in hair was demonstrated in the laser treated group (Lanzafame R).

Hair Removal Devices Several home-based hair-removal devices are available that attempt to replicate office devices, including the Tria Laser using a diode 810 nm laser (Tria Beauty, Inc, Dublin, CA, USA) and the Silk’n (Home Skinovations, Yokneam, Israel) that was developed according to the concept of IPL technology.

Acne Therapy Several home-based acne devices are also currently available. These devices use blue and red light diodes, heat, and IPL to treat mild to moderate acne, especially among patients who are hesitant to consider or have already failed other therapeutic options.

Bibliography 1. Weiss R, Doherty S. Clinical study of physician directed home-use non-ablative fractional device for the treatment of pigmented lesions. Abstract presented at American Society for Laser Medicine and Surgery Conference. Boston. April 2013;4-6.

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TRASER Total reflection amplification of spontaneous emission of radiation (TRASER) device, is a dye-based device, which uses three highly fluorescent TRASER dyes, PM 556 (pyrromethene 556), Rh 590 (rhodamine 590), and SRh 640 (sulforhodamine 640 chloride) (Exciton, Inc., Dayton, Ohio). This device amplifies spontaneous emission of radiation by capturing and retaining photons through total internal reflection; hence, the acronym. TRASER is associated with minimal dye degradation, as the dye is not stressed with typical laser gain pump levels, making the lifetime of the dye over 70,000 pulses. The characteristic carbon filter dye exchange depots used in current pulsed dye lasers (PDL) for the rhodamine dyes are not required in a TRASER as saturation of the dye-solution is not necessary or desired. Comparison of the currently configured TRASER with a PDL indicates that a TRASER is capable of providing several times the amount of energy when delivered over, for instance, 4 milliseconds at 12 mm. The workhorse PDL pulse train is limited to a 0.45 millisecond pulse before pulse degradation occurs. No such degradation occurs in a TRASER pulse because there is no population inversion required for the light amplification and no triplet state quenching of the pulse occurs, negating the need for cyclooctatetetraene (COT) or other additives to the dye solution. The ability to make variations in pulse durations may be useful and could affect treatment outcomes. For example, if an optimal pulse comprises a series of 0.45 millisecond pulses, then this could be reproduced with a TRASER. If on the other hand it is determined that a continuous flat 10–100 milliseconds pulse is desirable, then this too could be provided. Morgan Gustavsson, in their work showed a TRASER with appropriate wavelengths and pulse durations has more than enough energy to deliver clinically predictable effects.

Applications 1. One example of a prime target for a Traser would be hair removal. Studies indicate that high peak powers can be obtained at these wavelengths even over long 10–100 msec pulses, and as such this wavelength may well be considered more favorably in the future for hair removal. Clearly darker skin types would require reduced fluence, efficient cooling and longer pulse duration, but Asians and Caucasians in particular could benefit from the significant melanin/hemoglobin absorption differential with this wavelength. 2. Given the design of a Traser, it is generally more ecofriendly and safer than corresponding dye lasers. The current dye lasers use flammable and toxic organic solvents with additives, such as the cyclooctatetraene

New Aspects and Controversies in Lasers  491

(COT). By comparison, the Trasers are operated using water as the host (i.e. the solvent) for the Traser dye, and do not require toxic solvent additives. Furthermore, the closed system in a Traser avoids any dye or solvent contact with the operator. A Traser can be operated with a peak at any of the common yellow dye lasers without the use of any toxic solvents, solvent additives, or toxic dyes. Even with the use of rhodamines, with water as a solvent and without any additives, the Traser is ecofriendlier than the corresponding lasers. 3. Traser emission spectra match hemoglobin’s absorption wavelengths, indicating that a Traser could be used to treat the same vascular conditions as the PDLs by the same selective photothermolysis mechanisms. For superficial port wine stains, the shorter wavelengths with shorter pulse durations may be optimal, and for those with thicker, more nodular problems, the longer wavelengths with longer pulses might be preferred. Further, one can predict good responses in patients with lentigenes and in hair removal. 4. Given that a pulsed dye Traser is tunable, is should be able to mimic devices from below the 532 nm (green) to the near infrared wavelength simply by changing the dye kit. The durability of the flashlamps in a Traser are likely to be significant, given the relatively low peak powers and longer individual pulse durations (0.45 msec) and the consequent wear and tend on both the lamps. 5. Trasers should compare well with an intense pulse lights (IPL). Trasers have chromophor-absorption selective spectra that are quite similar to those of lasers. Since there is less interference by wavelengths induced by less selective absorption, the fluences required to induce the same peak power output is reduced. Even with short pulses, Trasers are capable of producing high peak powers within a narrow wavelength spectrum, a feature impossible in the case of IPLs. The fluences delivered from a Traser are in parity with, or exceed, those delivered by a comparable laser, even at short pulse-durations. This is even more evident when compared to an IPL. Thus TRASER is well on its way to become the next “IPL” in coming years. In fact it might be PDL cum IPL, though whether the clinical results reflect its design and dynamics is yet to be seen.

Bibliography 1. Gustavsson M, Spanogle JP, Berganza L, Zachary CB. TRASER: Dye Cell Aspect Ratio and Parallel vs. Sequential Pulsing and their Relation to Energy Output. Lasers in Surgery and Medicine (2014)46:140-3. 2. Zachary CB, Gustavsson M. TRASER—Total reflection amplification of spontaneous emission of radiation. PLoS ONE 2012;7(4):e35899.

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Conclusion There are many complex issues that arise out of lasers and their applications. As most publications are from experts, who to their credit, disclose affiliations with the laser and device manufacturers, its only when the results are replicated does the technology find universal acceptance. It is impossible to preempt such research as, it is essential to possess the identical technology and then report objective results. The first requires an endless source of funding and the latter time and expertise to publish, the combination of which is rarely see outside the countries of their invention. Thus, it is better to wait for studies from across the world specifically in skin types IV and V before investing in any new device. But as lasers and now TRASERS have multiple indications and involve big companies and investors, novel technology and applications will keep occurring and it is indeed a onerous task for the clinician to sift and decide what technology to invest. Whether home use devices will become common place remains to be seen but trends show that as clinicians become aware of the technological limitations the consumer may be directly targeted by companies. The future may see drug delivery via fractional lasers, and thus, this is a field that will remain “alive” for many years to come!

Acknowledgements We thank Dr Inder Raj S. Makin for his critical comments and suggestions to make the chapter relevant and topical. The lack of undue emphasis on Microfocused Ultrasound With Visualization in this chapter is as, an excellent contribution on the same has already been included in the book (Chapter 9).

APPENDIX

1

Laser Safety/Eye Care

CLASSIFICATION OF LASERS* Lasers are categorized into four hazard classes based on the accessible emission limits (AELs). These limits are listed in EN 60825-1 and the American National Standards ANSI Z136.1 for Safe Use of Lasers. The AEL values for the laser classes are derived from the medical MPE (maximum permissible exposure) values. The MPE values specify the danger level for the eye or the skin with respect to laser radiation. Since November 2001, the laser classes are as listed in Table A1.1. This classification (Table A1.1) has resulted in the introduction of three new laser classifications – 1M, 2M and 3R – and the abolition of Class 3A. The letter ‘M’ in Class 1M and Class 2M is derived from ‘magnifying’: optical viewing instruments. The letter ‘R’ in Class 3R, is derived from ‘reduced’ or ‘relaxed’ requirements. The ‘R’ requirement relates to certain equipment and user specifics, e.g. Manufacturer—no key switch and interlock connector required; User—no eye protection is usually required. The Letter ‘B’ in Class 3B is historical. It should be noted that in the previous laser classification scheme, lasers were grouped into four main classes and two sub-classes (i.e. 1, 2, 3A, 3B and 4); these classifications will still apply to older lasers that are currently in use. The pulsed lamp criteria, including IPL, apply to a single pulse and to any group of pulses within 0.25 seconds. The hazard values are at a distance of 200 mm. The risk group determination of the lamp being tested is detailed in the standard.

WARNING SIGNS AND LABELS The nominal hazard zone (NHZ) is the physical space in which levels of radiation, direct, reflected, or scattered, exceed the maximum permissible exposure (MPE), which may be determined by the safety information * Laser Classes to EN 60825-1 (Nov. 2001) and Safety

494  Lasers in Dermatological Practice Table A1.1 Classification of lasers Labels

Description

Comment

1

The radiation emitted by this laser is not dangerous

No need for protection equipment

1M

Eye safe when used without optical instruments, may not be safe when optical instruments are used

No need for protection equipment, if used without optical instruments (e.g. focusing lenses)

2

Eye safe due to aversion responses, including the blink reflex

No need for protection equipment

2M

The light that can hit the eye has the values of a class 2 laser, depending on a divergent or widened beam; it may not be safe when optical instruments are used

No need for protection equipment, if used without optical instruments

3R

The radiation from this laser exceeds the maximum permissible exposure (MPE) values. The radiation is maximum 5 times the acceptable emission limits (AEL) of class 1 (invisible) or 5 times the AEL of class 2 (visible) The risk is slightly lower than that of class 3B

Dangerous to the eyes, safety glasses are recommended

3B

Old class 3B without 3R. Directly viewing the laser beam is dangerous. Diffuse reflections are not considered as dangerous

Dangerous to the eyes, safety glasses are obligatory

4

Old class 4 Even scattered radiation can be dangerous, also danger of fire and danger to the skin

Personal safety equipment is necessary (glasses, screens)

provided by the manufacturer. While a Class III or Class IV laser is in operation, appropriate warning signs and labels, as well as protective equipment is administratively required for all individuals within the NHZ. Warning signs and labels are provided by the ANSI Z 136.3 in accordance with the Federal Laser Product Performance Standard, including the following two:

1. Display of Warning Signs Warning signs shall be conspicuously displayed on all doors entering the laser treatment controlled area (LTCA), so as to warn those entering the area of laser use. Warning signs should be covered or removed when the laser is not in use (see Atlas).

2. Inclusion of Pertinent Information Signs and Labels shall conform to the following specifications. (Figs A1.1 and A1.2) A. The appropriate signal word (Caution or Danger) shall be located in the upper panel.

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There are different logotype labeling requirements for Class IIIA lasers with a beam irradiance that does not exceed 2.5 mW/cm2  (Caution logotype) and those where the beam irradiance does exceed 2.5 mW/ cm2 (Danger logotype). Class II or Class III areas: All signs (and labels) associated with these lasers (when beam irradiance for Class III does not exceed 2.5 mW/cm2) use the ANSI CAUTION format: yellow background, black symbol and letters (Fig A1.1). Class III (beam irradiance 2.5 mW/cm2), Class III and Class IV lasers: Require the ANSI DANGER sign format—white background, red laser symbol with black outline and black lettering (Fig. A1.2). B. Adequate space shall be left on all signs and labels to allow the inclusion of pertinent information. Such information may be included during the printing of the sign or label or may be handwritten in a legible manner, and shall include the following. i. At position 1 above the tail of the sunburst, special precautionary instructions or protection action such as “Laser Surgery in Process – Eye Protection Required”. a. For Class II lasers and laser systems, “Laser Radiation: Do Not Stare into Beam.” b. For Class III lasers and laser systems where the accessible irradiance does not exceed the appropriate MPE based on a 0.25s exposure, “Laser Radiation: Do Not Stare into Beam or View with Optical Instruments.”

Fig. A1.1: Laser caution sign: CAUTION (Class II and some Class IIIR lasers). This label will also have the type of laser designated (HeNe, Argon, CO2, etc.) and the power or energy output specified

496  Lasers in Dermatological Practice

Fig. A1.2 : Laser caution signs :DANGER (some Class III R, all Class III B and Class IV lasers)







c. For all other Class IIIR lasers and laser systems, “Laser Radiation: Avoid Direct Exposure to Beam.” d. For all Class IIIB lasers and laser systems, “Laser Radiation: Avoid Direct Exposure to Beam.” e. For Class IV laser and laser systems, “Laser Radiation: Avoid Eye or Skin Exposure to Direct or Scattered Radiation.” ii. At position 1 above the tail of the sunburst, special precautionary instructions or protective action such as: “Laser Surgery in Process: Eye Protection Required.” iii. At position 2 below the tail of the sunburst, type of laser (Nd:YAG, CO2, etc.) or the emitted wavelength, pulse duration (if appropriate), and maximum output. iv. At position 3, the class of the laser or laser system.

Eye Safety Usually, the eyes protect themselves from damage that could be induced by excess radiation energy. If the retina detects high radiation intensity, the eyelid is closed in an automatic reaction. However, the time span that is necessary to close the eyelid is about 250 ms, which is definitely longer than most of the pulse durations used for lasers. In addition, this safety feature reliably works for an optical power of less than 1 mW, which is quite small compared to lasers or ILSs. Thus, the eye blink is not sufficient protection except against some nonmedical lasers classified in group 1. Radiation that is invisible for the eyes (ultraviolet, infrared) will not trigger an eye blink to protect the cornea, lens, or retina from damage. Users of

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lasers or ILSs should always keep in mind that even small intensities reaching the open pupil can cause severe damage of the retina, which in most cases is irreversible and may entail a complete loss of eye sight. Besides the eyes, radiation from lasers or ILSs can also damage skin outside the treatment area. One of the most important safety issues is the protection of the eyes from radiation that exceeds the maximum permissible exposure (MPE) values for the eyes. Essential parts of the eye such as the cornea, the lens, the choroid, and the retina can be subjected to radiation-induced damage. The part of the eye that sustains damage depends on the wavelength of radiation. The unwanted effects of radiation in the eye are more or less comparable to those effects at the treatment site. Depending on the intensity at the site of interaction, the well-known effects of coagulation (low intensity), vaporization (high intensity), and ablation (very high intensity) may occur. In the spectral range of light of about 370–1,000 nm, radiation readily penetrates the cornea and the lens to reach the choroid and retina. The radiation of this spectral range is, for example, well absorbed in hemoglobin in choroid vessels The induced heat simultaneously damages the retina. Additionally, when visible radiation passes the lens and cornea, the refraction increases the intensity of the incoming radiation by several orders of magnitude. The wavelengths from about 750–1,000 nm are particularly dangerous to the retina. Radiation in this spectral range is invisible and will not be detected by the eye and, therefore, the eye will not blink. The risk of damage to the eye depends on various factors including the wavelength, pulse duration, pupil size and amount of pigmentation of the pupil (Fig. A1.3 and Table A1.2). 1. UV-light below 350 nm either penetrates to the lens or is absorbed at the surface of the eye. A consequence of exposure to high power light at these wavelengths is an injury to the cornea by ablation or a cataract. 2. Light in the visible wavelength region (380–780 nm) penetrates to the retina. The eye is sensitive to radiation and humans have developed natural protective mechanisms. When light appears too bright, which means that the power density exceeds the damage threshold of the eye, we automatically turn away and close our eyes. This is known as an aversion response or blink reflex. This automatic reaction is effective for radiation up to 1mW power. With higher power levels, too much energy reaches the eye before the blink reflex can respond, which can result in irreversible damage. 3. The near infrared wavelengths (780–1400 nm) are a type of radiation that is particularly dangerous to the human eye because there is no natural protection against it. The radiation again penetrates to the retina, but the exposure is only noticed after the damage is done. 4. Infrared radiation (1400–11000 nm) is absorbed at the surface of the eye. This leads to overheating of the tissue and burning, or ablation, of the cornea.

498  Lasers in Dermatological Practice Table A1.2 Effect of light on the skin and eye Wavelength

Eye effects

Skin effects

Ultraviolet C (0.200–0.280 µm)

Photokeratitis

Erythema (sunburn) Skin cancer

Ultraviolet B (0.280–315 µm)

Photokeratitis

Accelerated skin aging Increased pigmentation

Ultraviolet A (0.315–0.400 µm)

Photochemical UV cataract

Pigment darkening Skin burn

Visible (0.400–0.780 µm)

Photochemical and thermal retinal injury

Photosensitive reactions Skin burn

Infrared A (0.780–1.400 µm)

Cataract, retinal burns

Skin burn

Infrared B (1.400–3.00 µm)

Corneal burn Aqueous flare IR cataract

Skin burn

Infrared C (3.00–1000 µm)

Corneal burn only

Skin burn

Fig. A1.3: Spectrum of light and its penetration into the eye

IMPLEMENTATION OF LASER SAFETY Eye Safety Standards Because physicians have to view the patient and the treatment area, the optical filters must fulfill both criteria at the same time: protection against laser or intense light sources (ILS) radiation and sufficient transmission of daylight to enable viewing. To achieve maximal safety for the eyes, it is important to adjust the optical filters of the safety goggles to the radiation source used (laser or ILS). The important parameters of the radiation sources

Laser Safety/Eye Care  499

are wavelength, pulse duration, intensity, and radiant exposure. These parameters of a laser or ILS system determine the characteristics of the safety goggles. Each laser or ILS requires special safety goggles that are labeled for their use (wavelength range of protection, laser mode, and scale number of protection). If a physician uses several lasers or ILSs, confusion of safety goggles of the different systems is possible and must absolutely be avoided.

Laser Safety Standards The MPE, maximum permissible exposure is a measure of the radiation exposure one can have without hazardous effect. This actually determines the OD and the NHZ. The American standard for laser safety eyewear only requires specification according to the optical density (OD) of the filters. The Optical Density (OD or D (l)) is the attenuation of light that passes through an optical filter. The higher the OD value, the higher the attenuation. The American standard also allows a Nominal Hazard Zone (NHZ) to be determined by the laser safety officer (LSO). Outside of the NHZ, diffuse viewing eyewear is allowed. However, in Europe there is a second criteria which must be taken into consideration - the power or energy density (i.e. the power or energy per area = per beam area). The “Diffuse viewing” condition is not allowed and laser safety glasses must protect against a direct laser exposure. Protection due to Optical Density alone is not sufficient when the material itself cannot withstand a direct hit. The European regulations are legal requirements and enforceable. Other legal requirements (e.g. the regulations for industrial safety as well as the medical equipment regulations) also refer to these. Laser safety eyewear ratings take both the eyewear filters and the eyewear frames into account to provide a specific rating for each different combination of wavelength, power and temporal mode of the laser. This differs from the optical density value. It is an absolute measure of the maximum power of the beam that the eyewear can withstand, without degradation to the performance of the eyewear. The European laser safety standards EN 207/EN208 also require that the frame also has to withstand the same level of radiation as the filters. The laser beam must be prevented from reaching the eyes from the sides and the filters should form an inseparable unit with the frame. The “weaker” part determines the protection level of the whole system for the specified wavelength and operation mode.

Understanding the Laser Safety Eyewear Rating Lasers differ from each other not only in wavelength or optical power, but also in the way in which the power is emitted. Power can be emitted continuously (continuous wave operation—Cw) or in form of pulses (long pulse, giant pulse/q-switched or mode-locked) (Table A1.3).

500  Lasers in Dermatological Practice Table A1.3 Summary of laser operation modes/pulse duration Operation mode

Description

Typical pulse length

Marking on eyewear

Continuous wave (Cw)

The continuous emission of laser radiation

< 0.2 s

D

Pulse mode

The short-term single or periodically repeated emission of laser radiation

> 1 µs to 0.25 s

I

Giant pulse mode (Q-switch)

It is like pulsed mode, but the pulse length is very short

1 µs to 1 ns

R

Mode locked

It is the emission of laser radiation with all the energy stored in the laser medium released within the shortest possible time

< 1 ns

M

In case of pulsed operation with a low pulse repetition rate, the peak power of each single pulse is the critical value. If the repetition rate increases, the average power needs to be taken into consideration. Please note that some lasers can be operated in different modes. Laser safety eyewear is specified according to these operation modes. Protective eyewear for repetitively pulsed lasers must satisfy the D rating as well as the I, R or M rating appropriate to its pulse length. The LB number is the scale defined in the Standard EN 207:2009. This specifies eyewear protection against laser radiation using a glass or plastic material. The LB rating calculation defines the minimum markings required on the laser safety glasses to ensure protection from the specified laser, at the target distance selected. The letters in front of the LB number refer to the temporal mode of the laser beam as seen above. D refers to Cw lasers or average Power Density (exposure time > 0.25s). I refers to lasers with pulse lengths between 1 ms and 0.25s. R refers to lasers with pulse lengths between 1ns and 1ms. M refers to lasers with pulse lengths less than 1ns. Protective eyewear for repetitively pulsed lasers must satisfy the D rating as well as the I, R or M rating appropriate to its pulse length. The second part defines the wavelength, or range of wavelengths, at which the rating is valid. The final part of the CE rating is the LB rating itself. This integer value represents the maximum power that the eyewear filters protect against. For example: D 532 LB3:  This eyewear delivers LB3 protection for a D type beam (continuous wave) at 532 nm.

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DIR 1000-1300 LB5: This eyewear delivers LB5 protection for D,I and R type beams across the wavelength range 1000–1300 nm.

BIBLIOGRAPHY 1. ANSI/IESNA RP-27.2-2000. Recommended Practice for Photobiological Safety for Lamps and Lamp Systems - Measurement Techniques. 2. ANSI/IESNA RP-27.1-2005. Recommended Practice for Photobiological Safety for Lamps and Lamp Systems - General Requirements. 3. ANSI/IESNA RP-27.3-2007. Recommended Practice for Photobiological Safety for Lamps - Risk Group Classification and Labeling. 4. Guidance on the safe use of lasers in education and research. Association of university radiation protection officers. Aurpo guidance note no. 7.2012, Revised edition. 5. IEC 60825-1 (2nd edition-2007). Safety of laser products - Part 1: Equipment classification, and requirements. 6. IEC 60825-1 (2nd edition - 2007). Safety of laser products - Part 1: Equipment Classification and Requirements, Corrigendum 1. 7. IEC 60825-1 (2nd edition - 2007) I-SH 01. Safety of Laser Products - Part 1: Equipment classification and requirements, Interpretation Sheet 1. 8. IEC 60825-1 (2007) 2nd edition I-SH 02. Safety of Laser Products - Part 1: Equipment classifcation and requirements, Interpretation Sheet 2. 9. IEC 62471 1st edition 2006-07. Photobiological safety of lamps and lamp systems. 10. IEC 60601-2-22, 3rd Edition 2007-05. Medical electrical equipment - Part 2-22: Particular requirements for basic safety and essential performance of surgical, cosmetic, therapeutic and diagnostic laser equipment.

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ATLAS

Fig. 1: This lens is used for Qsw Nd:YAG 532 nm, with a rating of L6. The marking “DIRM “ indicates that it covers all pulse durations and wavelengths as specified (180315,315-532nm). This is according to the European rating standards (CE)

Fig. 2 :This lens is used for CO2 laser. Note the wavelength and the OD

Fig. 3: This eyeware is used for IPL

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Fig. 4 : A laser safety label of a Class 4 laser (Er:YAG).Note the detailed instructions,including type of laser and class

Fig. 5: A laser safety label of a class 2 laser

APPENDIX

2

Consent Form

Name I understand that Dr will perform laser surgery on my (Specify location). I understand laser surgery consists of removing/treating . I understand that despite the ability of the device to help ameliorate the skin disorder, the following restrictions apply to the treatment: 1. The goal is improvement rather than perfection. There is no guarantee that the anticipated results will be achieved. 2. There may be significant swelling, oozing, and crusting, which may last for 1–2 weeks (ablative lasers). 3. Improvement may continue as time elapses after treatment. The final result may not be apparent for up to 1 year (fractional lasers). 4. If additional improvement is desired after this time, it may be possible to retreat areas. 5. Although pain management is a primary concern during treatment, some mild transient discomfort may occur, especially “stinging” after the procedure. 6. There is no guarantee that the results will be permanent. In rare cases, the skin can even look worse than before treatment. This may or may not be due to one of the complications or consequences of laser surgery. I understand that the following complications, although infrequent, can occur after laser treatment: 1. Scarring: This can occur in the form a raised or depressed red area with change in skin texture. Over time these may turn white. It is important that any prior history of abnormal scarring is reported. 2. Infection: Despite preventive measures, infection may occur, and additional medications may be necessary for treatment. 3. Color changes: There is a risk of temporary or permanent dark or light changes to the skin. 4. The likelihood of side effects will be decreased by my strict adherence to written postoperative instructions. Besides caring for the wound, avoiding sunlight exposure is critical, especially in the first 12 weeks after surgery.

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I have read this form and have been given the opportunity to discuss any questions I may have regarding the nature and aims of this procedure. Doctor (Name) Reg No. Laser FDA/CE/ISO 1. The risk, benefit and alternatives have been explained to the patient. Yes/No

2. The type of anesthesia given will be

Oral/Topical/Infiltration

3. Permission for release of photographs with masking of identification features has been taken

Yes/No

4. The patient has been informed about the right to revocation of consent. Yes/No  5. A “no guarantee” clause is implicit and the patient has been made aware that although the laser procedure is effective in most cases, no guarantees can be made that a specific patient will benefit from the laser treatment. Yes/No  6. The patient has choosen to undergo another laser treatment with inferior results, an informed refusal is appended.

Patient/Guardian Date

Surgeon Date

Witness Date

Yes/No

APPENDIX

3

Procedure Checklist

PREOPERATIVE CHECKLIST

1. 2. 3. 4. 5. 6. 7. 8.

Sign the consent form. Verify patient name. Verify procedure: Site, device. Ask patient for drug allergies. Review contradictions. Ask patient if he has any queries. Confirm pricing with patient. Confirm laser or device parameters to be used set correctly. Also wipe clean the lens and probes before starting the procedure. 9. Confirm protective eyewear. 10. Check for intraoperative cooling.

INTRAOPERATIVE CHECKLIST 1. Administer first pulse: Examine and confirm correct tissue response. 2. Stop treatment if tissue response not appropriate 3. Check patient pain level: If too high, stop.

POSTOPERATIVE CHECKLIST 1. Apply appropriate postcare products. 2. Review and give patient discharge instructions.

APPENDIX

4

Postoperative Care

Though full face resurfacing is not done nowadays, a few basic principles are useful to prevent complications for most laser procedures, specifically ablative lasers.

COOLING This is crucial to prevent pigmentation which is a issue in pigmented skin.

DRESSING Open techniques with use of topical agents is practiced commonly though in certain cases like, pyogenic granuloma, closed techniques and occlusive dressings (with or without topicals) can be used.

SCAR PREVENTION/INFECTION CONTROL Care should be taken immediately after completion of the procedure to minimize the probability of scar formation and bacteria or viral infection. Anti-inflammatory and antibiotics/antivirals can be used early in the recovery process to promote healing.

OVERVIEW OF POSTOPERATIVE CARE For convenience we are adopting the approach of Davis and Perez. Some of the interventions might seem aggressive and are essential if an ablative procedure is underatken. The mention of brand names is only indicative and does not indicate any endorsement.

1. First 2 Days Interventions Topicals/dressings, anti-inflammatory agents and antiseptic are needed. The basic aim is to enhance healing, reduce swelling and infection prevention.

508  Lasers in Dermatological Practice

1. Cooling: It makes sense to ask the patient to carry a ice pack as posttreatment cooling helps to eliminate most of the side effects. Thus while the patients procedure is being done the ice pack can be chilled which the patient can use afterwards. 2. Moisturizers: Post-treatment moisturizers should be non-occlusive in oily skin and occlusive in dry skin. Also it makes sense to use a preservative free and fragrance free product. A simple “thumb rule” is to use products, which are used for atopic patients as they satisfy most of the requirements. The products that we use include Aloevera gel (40– 50%) (ALoekem 75TM/Jula gelTM), CetaphilTM moisturizing cream, Physio gelTM and if possible EucerinTM (Petrolatum 41%). The aim is to enhance the healing and moisturized the skin. One common problem seen in patients undergoing laser hair removal at laser clinics is the presence of a low grade acne post laser.This is largely due to the use of “post-procedure” creams promoted by the laser clinics which contain comedogenic ingredients. Thus it is a useful step to check the products for such ingredients (Box A4.1). 3. Antibiotics: Topical antibiotics are often used and we prefer fucidic acid over mupironic acid. Oral antibiotics are given in ablative procedures and we prefer Levoflaxacin 750 mg HS for 7 days. 4. Antinflammatory agents: If antinflamatory agents are needed, it is better to use FucibetTM over FlutibactTM ointment as the latter is classified as a class III steroid while fucibet is a class V steroid. Thus the side effects are less with the former preparation. 5. Gentle washing with normal saline (0.9%) is ideal. Another option if there is crusting is the use of hydrogen peroxide (5%) 1:1 dilution which is an effective agent to remove crusts and prevent infection. 6. Dressing: In most procedures, an open dressing approach is employed except in ablative procedures where a closed dressing is used.We do not find any specific dressing to be superior for most routine cases.

Box A4.1 List of comedogenic ingredients in moisturizing cream Facial moisturizer

Beeswax Cetyl alcohol Carbomer Glyceryl stearate Jojoba oil Lanolin alcohol Mineral oil Myristyl lactate PG Dicaprylate/dicaprate Stearic acid Triethanolamine

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2. Next 3 Days to 1 Week Interventions The use of moisturizers, antibiotics,antivirals are needed to prevent scarring and infection The principles are same as above. The use of a mositurizer twice a day and a antibiotic cream at night is adequate. The crusting should not be removed manually to avoid scarring and post-inflammatory hyperpigmentation (PIH).

3. Next 14 Days Interventions Cleansers are used to remove crusting and cover and treat erythema. The intermediate recovery period is a transitional period from the active healing phase. If there is a hint of a scar formation, topical retinoids can be started. We prefer RevizeTM (Tretinoin 0.20%).

4. Next 3–4 Weeks Interventions Sunscreens: Protection from UV is highly recommended as the epidermis is regenerating and PIH if it occurs can mar any successful therapy.Because of the initial ablation of melanocytes, the skin may not be fully capable of photoprotection making it more susceptible to DNA damage. A few principles should be practised. 1. Use a sunscreen which is not excessively greasy or that which contains alcohol. 2. Always consider the patients skin type, an excessive oily, ingredient rich sunscreen is rarely applied consistently as the sticky feel can make compliance difficult. 3. A simple thumb rule is to use a physical block or a sunscreen with a mat finish as ultimately a proper use is more important than no use at all ! Micronized titanium dioxide (Suncross softTM/Sunstop 19TM) is an ideal sunscreen. Another option is to use a sunscreen with minimal ingredients, as all the ingredients are lipid soluble and thus more the components more oily the final sunscreen. Spectraban sensitiveTM that contains octinoxate and Tinosorb M is an ideal chemical block. We do not prefer administering sunscreens with multiple ingredients as there is a risk of allergenic sensitivities more so when the epidermis is damaged. Other measures like hats, protective clothing are useful as the substantivity of sunscreens and duration are restricted,specially in tropical countries like India.

510  Lasers in Dermatological Practice

5. Beyond 4 Weeks Interventions The most important intervention is bleaching agents to prevent pigmentation. While most pigmentation issues resolve themselves, some may need treatment or additional therapy to alleviate. Depigmenting agents are conveniently classified into three types (Table  A4.1) below. It is our experience that, post laser a tretinoin or HQ based cream or a triple combination preparation should be avoided. This is as the tretinoin causes inflammation which perpetuates the PIH. For the same reason the agenst that increase cell turnover should also be avoided. The search for the ideal agent, entails a product that contains a tyrosinase inhibitor more potent than HQ, which are azelaic acid, deoxyarbutin, dioic acid, ellagalic acid, embilca and licorice. Thus a preparation with any of these Table A4.1 Classification of depigmenting agents Agents that act before the stage of melanin synthesis

Agents that act during melanin synthesis

Agents that act after melanin synthesis

Tyrosinase transcription • C2-ceramide • Tretinoin

Tyrosinase inhibition • Azelaic acid • Arbutin • Hydroquinone • Kojic acid • 4-hydroxy-anisole • Methyl gentisate • 4-SCAP • Ellagic acid • Resveratrol • Aloesin • Oxyresveratrol

Tyrosinase degradation Linoleic acid a-Linolenic acid

Tyrosinase glycosylation • PaSSO 3 Ca

Peroxidase inhibition • Methimazole • Phenols/catechols

Inhibition of melanosome transfer • Niacinamide • Soybean/milk extracts • Serine protease inhibitors •L  ecithins and neoglycoprotein • RW-50353

Product reduction and ROS scavengers • Ascorbic acid • a -Toc F • Ascorbic acid • Palmitate D • L- a -Toc F • VC-PMG • Hydrocoumarins • Thioctic acid

Acceleration of skin turnover • Lactic acid • Retinoic acid • Glycolic acid • Linoleic acid • Liquiritin

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can be an effective inhibitor of melanin synthesis. This in combination with an agent that acts after melanin synthesis and does not cause irritation is ideal. A list of such products is given in Table A4.2, though we prefer MelaglowTM or DepiwhiteTM to prevent PIH. Table A4.2 Overview of common hypopigmenting preparations in India Brand

Agents that act before the stage of melanin synthesis

Agents that act during melanin synthesis

Agents that act after melanin synthesis

Melaglow

0.1 % THC 2% Kojic Acid

4%Niacinamide 0.2 % Soy Isoflavanoid

Depiwhite

2%Kojic Acid 2% HQ Vit C

Lactic acid Vitis vinifera Antipollon

Banatan

1% Mulberry extract 1% Deoxyarbutin

1% Licorice extract

Cosglo Octinoxate 7.5 % w/w,

Kojic dipalmitate 2% Arbutin 1.5 % w/w Pinus-pinaster bark extract 2%

Niacinamide 5% w/w

APPENDIX

5

Sample Operative Note

Procedure: CO2 Laser ablation (removal) Indication: Adnexal tumor Location: Face

PROCEDURE 1. The patient was counseled regarding the risks and potential benefits of the procedure. 2. Ninety minutes before surgery, a thick layer of EMLA cream was applied to the treatment site. The cream was removed just prior to surgery. 3. The face was cleansed with savlon solution to include a 2 cm perimeter of untreated skin. 4. The entire treatment area was surrounded with wet towels and the hair was wetted with sterile saline. 5. Approximately 0.2 mL of 2% lidocaine with 1:1,000,000 epinephrine was injected intradermally just deep to each lesion. 6. The lesions were treated with 175–250 mJ with the UltraPulse laser. The 1 mm spot size was used to ablate the lesion to a level where only stippled remnants of the base were observed. 7. Bacitracin/Fucidin ointment was applied, and written and verbal postoperative instructions were provided. 8. The patient was asked to follow up in 7–10 days. 9. The patient was discharged from the clinic in good condition. 10. Oral antibiotics and a NSAID were given for 5 days.

APPENDIX

6

Sample Postoperative Instructions (Ablative Lasers)

CONTINUOUS WAVE AND PULSED CO2 LASERS 1. Immediately after treatment, an antibiotic with or without a dressing will be applied. Any dressing will be removed 1–2 days after treatment. The dressing should be left alone until the next follow-up visit. 2. Avoid strenuous exercise for 10 days. Avoid unnecessary sun exposure. 3. There may be swelling after treatment, especially around the eyes (they may even be closed shut for 1 day). This will resolve within 3 days. An ice pack may be placed over swollen sites once the dressing has been removed. This may be done as often as 5–10 minutes every hour while awake. 4. Sleeping with your head elevated may reduce swelling. 5. For the next 1–3 days, the wound should be cleaned at home by applying either normal saline or hydrogen peroxide solution a cloth or gauze. After soaking with this for 10–15 minute, any excess crusts can be gently removed by using a cotton bud. Occasionally, pinpoint bleeding may occur; this can be stopped by applying gentle pressure for several minutes. After cleaning the wound, a petrolatum-type ointment or antibiotic ointment should be applied. 6. Allow shower water to irrigate the wound but avoid use of soaps to the open skin. Once the skin is healed (no open areas), your normal soap may be resumed. 7. Please follow-up visits weekly for the first 3 weeks after treatment. 8. In case of rash, fever, or severe pain please come back for a visit.

AFTER 1 WEEK 1. After 1 week normally, the skin will be healed enough for you to be able to go outside. The face should be covered with a broad- spectrum sunscreen (at least SPF 15) and the head covered with a broad-brim hat. If your face is sensitive a physical block can be used. It is most important to avoid any sun exposure as long as the skin is pink. 2. A concealer or a flesh-tone foundation can then be applied. 3. A light non-comedogenic moisturizer can be applied ad lib (Cetaphil, Secalia, Physio gel, Sebamed Clear gel). 4. Apply a steroid cream every night if your doctor prescribes it for redness.

APPENDIX

7

Patient Information Sheet

PATIENT INFORMATION SHEET (HAIR REMOVAL) Which Methods of Hair Removal are Possible? The various methods employed include, shavers, hair removal cream, wax stripes,threading or electric epilating devices are mostly used. These are only temporary methods of hair removal, and moreover the electric epilation requires much effort. Shaving is one of the most commonly applied procedure, but its result can be seen only a few days and a post-treatment is continuously required to get rid of unwanted hair. The plucking of hair has a longer effect than shaving but it causes pain, is used for smaller areas and can cause folliculitis. The hair removal by using wax is similar to the plucking method and allows the treatment of larger areas. Like hair plucking, the wax method can also cause much pain and allergic reactions, inflammations of the hair bulb in particular. Lasers and flashlamps ensures a reliable, effective and relatively painless removal of unwanted hair. The possibility of a simultaneous treatment of several hairs that are close together increases the effectiveness. The laser/flashlamp has been designed for the selective destruction of the hair roots so that a skin irritation known from the other methods is nearly not caused.

Laser Hair Removal The high-energy light penetrates the skin up to a depth of several millimeters, passes the upper skin layer and the brown pigment (melanin) of the hair in the skin absorbs the light energy specifically and converts it into heat. Thus the cell layers (hair root and bulb region) surrounding the hair and being responsible for the hair growth are heated so that they are permanently damaged.

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As the epilation by means of high-energy light is adjusted to dark (pigmented) hair, red, blond or grey hairs respond less to it. Hair grows in different phases. The single human hairs are in different growth phases. The light energy only damages the hairs that are in an early growth phase because afterwards the hair detaches from the hair root so that the root is not heated any longer. Therefore, 6 or 8 sessions are required for each person. A higher treatment repetition rate increases the probability to strike each hair once in its sensitive growth phase. The interval between the treatments should be 4 to 8 weeks and depends on the treated part of the body. As long as hair has not grown again in the treated area, a new session would not be useful because none of the hairs is in the growth phase then. The effectiveness mostly depends on the color, thickness and depth of the hair as well as on the hormonal level and the genetic disposition. The best effects can be reached, if the skin is not tanned and the hair is dark. To avoid unwanted side effects, it is recommended to be as pale as possible before the treatment or to start the treatment in winter, because tanned skin also contains melanin in its upper layer. Often, a hair removal of 100% cannot be achieved. In particular, fine and / or light hair can remain. Therefore, it is better to speak about a reduction of hair. Depending on the genetic disposition and the hormones, new hair can grow from the numerous sleeping bulbs in the skin after a longer period. In these cases, a post-treatment is necessary, but not again a complete series of sessions.

What is the Treatment like? After applying a water-containing gel, the system handpiece is positioned on the skin and emits a light pulse that gives you a feeling of a slight prick. Then, the handpiece of the laser is moved over the areas to be treated. The upper skin layer is cooled simultaneously. If one hour before the treatment an anesthetic ointment is applied, you do not feel anything. After the treatment skin reddening and/or a feeling of heat can be caused. The release of tissue-active substances can cause little swellings around the hairs. This phenomenon is particularly typical for very dark and thick hair. As a whole, the side effects can be compared with slight sunburn. The hair comes loose, loses its support and finally falls out. Particularly for thick hair, this effect can be produced after only maximum 2 weeks. The hairs growing again are mostly thinner and lighter than the original ones. The next treatment can be performed after 4 to 8 weeks, if new hairs grown in the meantime are visible.

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What Aspects Must be Considered Before the Treatment? Shave your hair to skin level one day before the treatment. The treatment area should not be tanned. Do not pluck your hair by means of pincers, wax or electric epilators for 4–6 weeks before the treatment. If necessary, apply EMLA ointment on the sensitive areas 1 hour before starting the treatment.

What Aspects Must be Considered After the Treatment? Cool the area to be treated as long as you have a pleasant feeling. Slight crusts can develop on sensitive skin and must not be manipulated. Do not expose the treated area to the sun or intensive light (solarium) without protection for at least 6 weeks. If you observe skin irritations that have not been mentioned here, please contact the doctor responsible for the treatment!

What the doctor should know: What is your natural hair color? What is your natural skin color? Genetic lineage: Are you tranned at present?

☐Yes  ☐No

Do you have allergies or hypersensitivity reactions, particularly against light? if yes, which ☐Yes  ☐No Do you take drugs at present? If yes, which:

☐Yes  ☐No

Are you prone to skine diseases, e.g. acne, herpes simplex, psoriasis or difficult wound healing? if yes, which: ☐Yes  ☐No Do you suffer from chronic or acute diseases? if yes, which: Which method have you used so far to remove unwanted hair? ☐Epilation device  ☐Plucking   ☐Wax ☐Shaving   ☐Bleaching   ☐Creams ☐Electric epilation Frequency:

☐Yes  ☐No

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PATIENT INFORMATION SHEET (PIGMENTED LESIONS/TATTOO) What Happens if You Get a Tattoo? When a tattoo is made, a colorant is injected into the skin. These colorants are partly simple Indian inks, but the tolerability of the inks that are often used today has not always been thoroughly tested. In such a procedure, the ink particles are implanted under the upper skin layer (epidermis) in a depth of about between 0.5 and 2 mm. During the healing phase, the body’s immune system tries to remove the foreign substances. As the ink particles cannot be metabolized directly by the body due to their size, they are isolated from the surrounding tissue by a connective tissue coating. Rest are removed by the lymphatic system. These rests can be detected in the lymphatic system during all your life.

How Does a Laser Device Function? A laser is a device that generates a defined light color with high precision and focuses an extremely narrow light beam. The effect of each light color is specialized to a specific skin structure so that it is possible to remove unwanted skin changes without damaging the tissue surrounding them. The emitted laser light has a high power but is primarily absorbed by the colorants of the tattoo, the dirt particles or the melanin. Due to the specific absorption, the side effects are low and the healing phase is short.

How Does the Laser Function in such a Treatment? The laser beam penetrates the skin and the ink or dirt particles or the melanin absorb the light energy. The encapsulated ink particles or the melanin are/is promptly pulverized by the mechanical effect of extremely short light pulses. The split particles are removed by the lymphatic system. This process takes time. Therefore, the subsequent sessions are only useful after several weeks.

What Is the Treatment Like? First, your eyes are protected by a laser-protective eye-wear. The spacer of the laser handpiece is positioned onto the skin and after the activation of the laser via the foot switch a light pulse is emitted and you feel a slight prick. Then, the handpiece of the laser is moved over the areas to be treated. Each treated point looks white first, like a blister. This will vanish after several minutes.

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After the treatment reddened skin, a strong feeling of heat and / or urtication can be caused. Dot-shaped bleedings cannot always be avoided. After a few hours, the treated areas can become darker and minor crusts develop and will disappear after several days. The next treatment can be performed after 6 to 8 weeks. The number of sessions depends on the amount of ink particles or melanin contained in the skin and on the specific part of the body. The tattoo cannot always be removed completely. As the light energy is better absorbed by dark colorants, lighter particles show less response to them. In particular for color tattoos (e.g. permanent makeup) changes of the color can also be observed and in rare cases they cannot be removed. Therefore, try to give the doctor a sample so that it is possible to test the properties of the injected colored ink even before the treatment.

What Aspects Must be Considered Before the Treatment? 1. The treatment area should not be tanned. 2. If necessary, apply EMLA ointment on the sensitive areas one hour before starting the treatment.

What Aspects Must be Considered After the Treatment? 1. Cool the area to be treated as long as you have a pleasant feeling. 2. Never manipulate crusts. 3. Do not expose the treated area without protection to the sun or intensive light (solarium) for at least 6 weeks. 4. If you observe skin irritations that have not been mentioned here, please contact the doctor responsible for the treatment.

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PATIENT INFORMATION SHEET (VASCULAR LESIONS) How Does a Laser/Flashlamp Treatment Works? The high-energy light (of the laser/flashlamp) penetrates the skin and is absorbed by the blood pigment hemoglobin. The absorbed energy heats the blood vessel. This leads to the closure of the vessel. The duration of this process depends on the size of the vessel: The larger the vessel the longer the procedure (for deep bluish vessels the treatment can take some months). Laser/flashlamps can emit different wavelengths (colors). As the blood absorbs the green color particularly well, the green light is best suited for small vessels that are normally red and superficial. But the water absorption is very low. As the skin normally contains a lot of water, the surrounding skin is heated only a little bit and not influenced by the light very much. Therefore, the risk of scars on the skin is very low. Larger and deeper vessels (mostly bluish) are to be treated preferably by infrared light that is more effective because it can penetrate the skin deeper.

What is the Treatment Like? This skin is cooled before the treatment. The larger the vessels and the area to be treated, the longer the time required for cooling. Your eyes are protected from the laser light by laser protective eye-wear or covered by light-proof eye patches. The doctor moves the handpiece over the area to be treated. You will feel slight pricks that are a sign of the effectiveness of the therapy. Normally, anesthesia is not necessary. The period of the treatment depends on the size of the relevant area and is normally not longer than a few minutes. Depending on the size of the lesion, reddening and swelling can be observed after the treatment. In some cases, slight crusts can develop and should never be manipulated. Whereas fine red blood vessels of the face can be removed in 1 or 2 sessions, the removal of larger vessels of the leg is more difficult. The latter do not always respond to the treatment. For other indications, it can be necessary to perform more than just one session at intervals of several weeks.

What Aspects Must be Considered Before the Treatment? 1. You are not tanned in the area to be treated (no sun exposure for 4 weeks before the start of the treatment). It is a good idea to initiate therapy in autumn or winters. 2. You do not take drugs that inhibit blood coagulation (e.g. Aspirin). 3. The area to be treated is free of pathological findings (no inflammation, suppuration, etc.).

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Immediately before the treatment: 1. The area to be treated is carefully cleaned, cream and makeup are removed. 2. If necessary, the area to be treated must be shaved carefully.

What Aspects Must be Considered After the Treatment? 1. Cool the area to be treated as long as you have a pleasant feeling. 2. Possibly developed crust must not be manipulated. 3. Do not expose the treated area without protection to the sun for at least 6 weeks. 4. Avoid intensive physical exercises, hot bathes and do not go to the sauna for 5 days after the treatment. 5. Prevent the skin from reddening by alcohol, hot spices or similar substances. 6. If you observe skin irritations that have not been mentioned here, please contact the doctor responsible for the treatment.

What the doctor should know: Are you prone to keloiding?

☐Yes  ☐No

Are you tanned at present?

☐Yes  ☐No

Do you have allergies or hypersensitivity reactions, particularly against light? if yes, which ☐Yes  ☐No Do you take drugs at present? if yes, which

☐Yes  ☐No

Are you prone to skin deseases, e.g. acne, herpes simplex, psoriasis or difficult wound healing? if yes, which ☐Yes  ☐No Do you suffer from chronic or acute diseases? if yes, which

☐Yes  ☐No

For women: Could you be pregnant?

☐Yes  ☐No

Do you smoke? if yes, how much:

☐Yes  ☐No

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PATIENT INFORMATION SHEET (ABLATIVE LASERS/FRACTIONAL) Which Skin Lesions can be Treated by Means of an Ablative/Fractional Laser? As one becomes older, the skin loses its elasticity and the connective tissue shrinks. Wrinkles and also other irregularities of the skin surface develop. Many of these changes can be treated by using ablative lasers, e.g.: 1. Stretching out minor wrinkles (no expression lines) 2. Skin lifting 3. Ablation of protruding scars 4. Stretching out acne scars 5. Ablation of keratinized tissue 6. Removing (benign) birthmarks 7. Removing cholesterol deposits around the eyes 8. Removing warts and other treatments. For fractional lasers though there is a long list of conditions that respond,acne scars, early photodamage and rejuvenation are the common responsive disorders.

How does the Laser Ablation Function? The lasers used for ablation have a wavelength (in the infrared range) that is strongly absorbed by the water contained in the skin. In this way, the skin is ablated pulse by pulse in an almost “cold” manner. Two different methods exist for the ablation: Ablative lasers (CO2/Er:YAG): In case of more intensive skin changes the upper skin layer is ablated completely in the area to be treated. Fractional Lasers: For skin rejuvenation it is also possible to apply a stateof-the-art procedure in which the upper skin is only ablated in a spot-like manner (microspots). This method is called fraction ablation. In the fractional ablation, a large part of the skin between the microspots remains untreated and therefore less side effects are caused.

What is the Treatment Like? Your eyes are protected from the laser light; additionally you should shut your eyes. The handpiece of the laser device is placed on the skin. Ablative lasers (CO2/Er:YAG) The unwanted lesion or the area to be treated is ablated precisely by removing extremely thin layers by several light pulses per second with a spot size of few millimeters. The treatment of minor lesions, such as birthmarks or warts, takes only a few minutes, larger areas require considerably more time. For larger areas

522  Lasers in Dermatological Practice

to be treated, a local anesthesia, seldom anesthesia, is necessary. Often one treatment session is sufficient, but some indications require several sessions.

Fractional Lasers Here only tiny microspots are ablated in the area concerned within the spot having a size of about one square centimeter. As this procedure is normally used for treating larger areas, e.g. the whole face. This treatment can take a period of between a quarter and half an hour, local anesthesia is normally not required. To achieve an optimum result it can be necessary to perform more than one session at intervals of several weeks.

What Aspects Must be Considered Before the Treatment? You are adult. For women: You are not pregnant. 1. You are not tanned in the area to be treated. 2. You do not take drugs that inhibit blood coagulation (e.g. Aspirin). 3. The area to be treated is without pathological findings (no inflammation, suppuration, etc.). 4. If an anesthesia is required, you will be informed separately. Immediately before the treatment: 1. The area to be treated is carefully cleaned, creams and make-up are removed.

What Aspects Must be Considered After the Treatment? 1. UV protection for the treated area for 12 weeks, in case of extensive ablation of larger areas even longer. 2. For minor lesions: The area must heal without manipulation of the crusts. 3. Do not do any works during which the treated area comes into contact with dirt or dust.

Laser Safety/Eye Care  523 What the doctor should know: Do you suffer from chronic or acute diseases? (including metabolic disorders, high blood pressure) if yes, which ☐Yes  ☐No Do you have a cardiac pacemaker, implants or prostheses? if yes, which ☐Yes  ☐No Do you suffer from blood clotting disorders? (intensive bleeding of injuries, hematomas after slight shocks) ☐Yes  ☐No Could you be pregnant?

☐Yes  ☐No

Do you take drugs at present, e.g. anticoagulants such as Marcumar, Aspirin? if yes, which ☐Yes  ☐No Are you prone to keloiding?

☐Yes  ☐No

Do you have allergies, particularly against light? if yes, which

☐Yes  ☐No

Do you have lip blisters (herpes) or acne?

☐Yes  ☐No

Do you often suffer from infections?

☐Yes  ☐No

Do you smoke?

☐Yes  ☐No

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PATIENT INFORMATION SHEET (RADIOFREQUENCY) What Does Skin Ageing Mean? In the course of time, the skin loses its elasticity and strength, wrinkles develop. Apart from the genetic disposition and hormones, this process is also influenced by environmental factors, such as UV radiation or nicotine. The net-like branched collagen fibers of the corium are damaged and partly they lose their reproduction capability. The process of collagen reproduction can be stimulated again by radiofrequency treatments. A firm skin and minor wrinkles are the result. Several sessions are necessary to obtain an optimum effect.

How Does a Radiofrequency Device Function? In the radiofrequency therapy an intensive depth heat is generated. It tightens the treated skin areas without damaging the surrounding tissue. When the skin surface is cooled by the handpiece, the connective tissue is slightly heated by the high-frequency RF current. This causes the contraction and lifting of collagen. Simultaneously, the collagen reproduction is stimulated and has an additional lifting effect after some weeks. Immediately after the treatment you can go in for your normal activities.

How Does the Radiofrequency Treatment Function? Radiofrequency power can generate heat within the skin. The heat intensity depends on the power used and the duration of the RF current influence. Depending on the individual skin resistance and water contents these parameters can vary from one patient to the other. Therefore, a test treatment is performed first to determine the optimum parameters. The skin is soaked to the handpiece by low pressure and RF current is specifically applied in the volume soaked in. In this process, high-frequency waves are emitted between the electrodes. Simultaneously, the handpiece ensures the cooling of the epidermis. This procedure leads to a selective heating of the soaked-in skin and thus the collagen is lifted. The combination of radiofrequency and massage is generated by a pulsating low pressure. Thus, the cell reproduction is stimulated additionally. The described treatment method can be applied both for the face and for the body.

What is the Treatment Like? The handpiece of the RF device is placed onto the skin. A defined proportion of the skin is firmly soaked to the handpiece and radiofrequency is generated at the same time. This process lasts some seconds and is repeated at the next area then until the whole defined area is treated.

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During the RF treatment a slight feeling of heat can be caused. If you feel pain during the treatment, please inform the doctor immediately. Then, the parameters will be reduced. It is not recommended to endure the pain. To obtain an optimum result, several sessions are necessary, mostly 6 to 8. A pause of 2 weeks should be kept between the treatments.

What Aspects Must be Considered Before the Treatment?

1. 2. 3. 4. 5. 6. 7. 8.

You are adult and healthy. You did not undergo an operation during the last 4 weeks. You did not get isotretinoin in an acne therapy during the last 4 weeks. You are not pregnant. You do not take drugs that inhibit blood coagulation (e.g. Aspirin). You are not prone to keloids. You are not prone to difficult wound healing. The area to be treated is free of pathological findings (no inflammation, suppuration, etc.). Immediately before the treatment: ¾¾ Remove makeup and deodorant. ¾¾ Before the treatment, a couple gel is evenly applied on the skin.

What Aspects Must be Considered After the Treatment?

1. 2. 3. 4. 5.

If necessary, cool the treated area as long as you have a pleasant feeling. Do not have a hot shower for one day. Apply moisturizing cream, possibly an anti-inflammatory ointment. Avoid sun exposure and solarium for one week after the treatment. If you do not detect skin reactions apart from a slight reddening, you can use makeup again.

526  Lasers in Dermatological Practice What the doctor should know: Do you suffer from chronic or acute diseases? (incl. metabolic disorders, high blood pressure) If yes, which: ☐Yes  ☐No Did you undergo operations or acne therapies during the last 4 weeks? If yes, which: ☐Yes  ☐No Do you have a cardiac pacemaker, implants or prostheses? If yes, which: ☐Yes  ☐No Are you prone to blood-clotting disorders? (intensive bleeding of injuries, hematomas after slight shocks) ☐Yes ☐No Could you be pregnant?

☐Yes ☐No

Do you take drugs at present, e.g. anticoagulants such as Marcumar or Aspirin, immunosuppressive agents? If yes, which: ☐Yes  ☐No Do you suffer from allergies? If yes, which:

☐Yes  ☐No

Are you prone to keloiding, bad wound healing or atrophy? ☐Yes ☐No Do you suffer from skin inflammations, open wounds or dry skin? ☐Yes ☐No

Laser Safety/Eye Care  527 Diagrammatic representation of areas to be treated

APPENDIX

8

Local Anesthetics

LIDOCAINE Lidocaine, an aminoethylamide, is the prototypical amide local anesthetic.

Mechanism of Action Local anesthetics block conduction in nerves by minimizing or preventing the influx of sodium ions, thereby preventing depolarization. The type C pain and itch fiber nerve conduction are blocked.

Pharmacology Onset of action