Primary Eye Care Manual

Interprofessional Fostering of Ophthalmic Care for Underserved Sectors

a non-profit organization promoting “eye care for all"

Primary Eye Care and Training Manual

reaching out to people and programs near and far to promote healthy eyes and clear vision for all

Interprofessional Fostering of Ophthalmic Care for Underserved Sectors

a non-profit organization promoting “eye care for all"

Named “Outstanding Project 1998” by the American Public Health Association Vision Care Section Member of World Health Organization Partnership Committee of Non-governmental Organizations dedicated to the Prevention of Blindness

Dr. Ian Berger President

InFOCUS 19728 Saums Rd., PMB #136 Houston, Texas 77084 Ph: 281 398 7525 Fax: 281 398 7428 Email: [email protected] Website: www.infocusonline.org

ACKNOWLEDGEMENTS Ms. Diane Baker Dr. Ian B. Berger Ms. Mary Dipboye Ms. Del Garcia Dr. Simon Gould Ms. Diana Grigsby Dr. Jean-Paul Heldt Ms. Jillian Hopewell Dr. Ravi Kankaria Ms. Barbara Kazdan Dr. Christoph Lengwiler Dr. Valerian Lyimo Dr. Patrick McColloster Dr. Kavita Mistry Ms. Vasu Mistry Dr. Nghiem Pham Ms. Jan Rueb Ms. Victoria Sheffield Dr. Larry Spitzberg Dr. Scott Swann Dr. Jerry Vincent And the students of the University of Houston College of Optometry

Overall objective of this training seminar is to:

Promote a high standard of practice for all engaged in primary eye care, especially for non-eye care professionals and volunteers working with medically underserved and economically disadvantaged populations

“Primary Eye Care Training and Reference Manual” Contents Introduction ..............................................................................................1

Module 1

Eye Anatomy, Functions & Common Sight Problems ................................................................................................5 Anatomy of the Eye ....................................................................................6 How the Eye Works....................................................................................8 Common Sight Problems............................................................................9 • Visual Acuity • Refractive Errors • Other Problems Professional Eye Exams...........................................................................11 • Recommended Schedule and Benefits

Module 2

Vision Assessment ...........................................................................13 Protocol for Primary Eye Care Examination .............................................13 Patient Record Form ................................................................................14 Visual Acuity Charts .................................................................................15 • Measuring Distance Vision..................................................................16 • Measuring Near Vision........................................................................17 • Pinhole Occluder.................................................................................19 Screening for Binocular Dysfunction.........................................................20 Screening for Coordinated Eye Movement ...............................................21 Screening for Limitations of Visual Field...................................................22 Screening Color Vision .............................................................................23 Screening for Acanthosis Nigricans..........................................................24 Measuring Refractive Errors using FOCOMETER® .................................25 • FOCOMETER® Fact Sheet ................................................................25 • How to Read FOCOMETER® .............................................................26 • Using FOCOMETER® for Refractive Error .........................................28 • Using FOCOMETER® for Astigmatism Error......................................30 • Clock Target........................................................................................33 • Care and Maintenance........................................................................34

Module 3

Eye Health and Safety ......................................................................35 Preventive Practices.................................................................................35 Basic Primary Eye Care Techniques........................................................36

Module 4

Eye Injuries & Disease .....................................................................39 Assessing Eye Conditions ........................................................................39 Common Eye Diseases ............................................................................42

Module 5

Referrals ............................................................................................... 47 Criteria for Referring Patients to Eye Care and Medical Care Professionals ................................................................ 47 Referral Procedure................................................................................... 47

Module 6

Dispensing Eyeglasses ................................................................... 49 Eyeglass Frames & Lenses...................................................................... 49 Customized vs. Recycled Glasses ........................................................... 50 Protocol for Dispensing Customized Glasses .......................................... 51 Recycled Eyeglasses – Sorting & Inventory............................................. 52 Protocol for Dispensing Recycled Glasses............................................... 53 Protocol for Dispensing Reading Glasses................................................ 54 Using FOCOMETER® to Neutralize the Corrective Power of Lenses....... 55 Using Spherical Equivalent to Correct for Astigmatism ............................ 57 Sources of Inexpensive Eyeglasses ........................................................ 59 Procedure for orienting cylinder axis when assembling Instant Eyeglasses™ ......................................................................... 60 Measuring Pupillary Distance (PD) ......................................................... 61 How to Read a Prescription...................................................................... 62

Module 7

Record Keeping ................................................................................. 63 Maintaining Clinical and Fiscal Records................................................... 63

Appendix Glossary ................................................................................................... 65 Eye Care Websites .................................................................................. 69 Equipment / Materials List for Primary Eye Care...................................... 73

Introduction Introducing InFOCUS InFOCUS (Interprofessional Fostering of Ophthalmic Care for Underserved Sectors) began in 1987 as an outreach project of the University of Houston College Optometry. The project produced the FOCOMETER®, an affordable refracting device appropriate to areas without access to professional personnel, electricity or costly equipment. This device became the centerpiece of a unique program designed to help medically underserved communities achieve self-reliance for basic vision care. In 1995 InFOCUS was chartered as a non-profit 501c3 organization with a mission to provide eye care to all populations, beginning with those most in need and hardest to serve due to poverty or geographic remoteness. Its strategy is to train local service providers to provide primary eye care. Its goals are to improve vision, prevent blindness and promote health. Why is InFOCUS Needed? As many as 900 million children and adults in the world today are visually impaired due to refractive errors that could be corrected by prescription eyeglasses. The World Health Organization estimates that 75% of the world’s blindness could be prevented or treated. Toward that goal, InFOCUS helps large, medically isolated populations acquire basic vision services and the capacity to link patients to professional care. What Does InFOCUS Do? Working with health care providers and other agencies serving low-income communities InFOCUS • Fosters sustainable, community-based eye care services • Promotes eye health through education • Helps disadvantaged people gain access to basic vision services and preventive health education In the United States, InFOCUS trains health and social service providers and community volunteers to promote preventive practices, assess vision, and refer patients to qualified practitioners for eye exams and eyeglass prescriptions. InFOCUS helps its program partners set up “vision stations” offering lowcost, quality eyeglasses to individuals who could otherwise not afford them. InFOCUS also trains and equips clinicians and volunteers to offer eye care on short-term mission trips. In other countries, InFOCUS provides the technology, training, and an initial supply of low-cost lenses and frames to help communities set up vision stations. Community eye care providers measure refractive errors, dispense glasses, and use the proceeds of spectacle sales to defray operating costs. InFOCUS works with program partners to • Establish and sustain a vision station • Provide an appropriate standard of care • Provide health education to promote the prevention of eye and other diseases • Refer patients with serious eye conditions to appropriate medical resources The InFOCUS Center for Primary Eye Care Development Based in Houston, Texas, the InFOCUS Center for Primary Eye Care serves as the hub of global efforts to expand access to vision care. Working with universities, professionals and health organizations, the Center • Provides training, information resources and technical assistance to service providers • Promotes awareness of primary eye care needs and program strategies • Fosters research on clinical methods and technologies • Initiates and participated in collaborative projects; and • Develops and implements programs to respond to critically unmet needs. InFOCUS reaches out to people and programs near and far to promote healthy eyes and clear vision for all. 1

Primary Eye Care and FOCOMETRY Primary eye care is considered the “first encounter” with eye care. Often, the only eye care offered to many people in poor and rural communities is a vision screen. About one billion people need an eye exam but do not have access to an eye care provider. The Need for Eyeglasses One of the most widespread eye problems is simply the need for eyeglasses. At least 900 million people in the world today need a correction for visual refractive errors (i.e., need eyeglasses). However, many are unable to obtain a prescription because of geographic or financial barriers. Despite abundant good will on the part of eye care professionals and medical institutions to reach out beyond their usual service areas to individuals and populations in need, only a tiny fraction of the need is being met. FOCOMETER® Key to Removing Barriers The FOCOMETER® is helping people to gain access to basic vision care. Because the FOCOMETER® is an accurate, affordable, and easy-to-use tool for measuring refractive errors, it is being used in 40 countries with medically underserved populations, including communities in remote locations. InFOCUS is training and equipping health workers and non-medical volunteers to measure refractive errors and dispense appropriate eyeglasses. As a result, the burden of poor vision has been lifted from many people around the world. The FOCOMETER® requires no electricity and has been found to be as accurate as the auto refractor in field trials that have been published in scientific journals. The FOCOMETER® enables the measurement of refractive errors of patients who need eyeglasses, and can also be used to determine the corrective power of prescription eyeglasses (neutralization).

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Uses for This Manual Primary Eye Care Assessment: 1. Measuring visual acuity, screening for binocular dysfunction and color vision problems; 2. Determining which patients have refractive errors and need eyeglasses; 3. Recognizing symptoms of eye diseases; 4. Determining prescriptions for eyeglasses using Focometry; 5. Promoting eye health; and 6. Making appropriate referrals. Eyeglass Dispensing: 1. Managing and dispensing recycled eyeglasses; 2. Dispensing customized glasses; 3. Using a spherical equivalent for dispensing glasses to patients with astigmatic error; and 4. Maintaining clinical and fiscal records.

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Module 1 – Eye Anatomy, Functions & Common Sight Problems Introduction to Anatomy of the Eye The human eye is truly one of the most remarkable organs in the body. The sense of vision requires a light receptor (the eye), a pathway by which nerve impulses are conveyed (the optic nerve), and an area in the brain (the visual cortex) that transforms the nerve impulses into images of color and form.

External Structure The human eyeball is surrounded by the cone shaped bony eye sockets and padded by layers of fatty cushions. Moveable eyelids, eyelashes and tears secreted by the lacrimal gland, which protects the eye against external debris or potential abrasions. Tears continue to flow at all times, washing away foreign particles, lubricating the eyelids, and keeping the transparent cornea moist. Excess tears drain into the nasal cavity through the nasolacrimal duct. (Fig. 1)

Fig. 1 Front view showing the lacrimal gland and nasolacrimal duct through which tears drain into the nasal cavity

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Anatomy of the Eye

Fig. 2 Horizontal cross section through the right eye showing interior structures

The Eyeball The eyeball has three covering layers. The outermost layer is a tough, fibrous, white membrane and is called the sclera. In the center of the sclera and projecting slightly is the cornea, a transparent membrane that acts as the window of the eye. The choroids, the layer beneath the sclera, is composed of dense pigment and blood vessels that bring oxygen and nourishment to the cells of this structure and to the other coats as well. The choroids prevent reflection of the light inside the eye. Near the center of the visible part of the eye, the choroids form the ciliary body, the muscles of which change the shape of the lens. The ciliary body merges with the iris, a muscular diaphragm that regulates the size of the pupil, the round opening through which the light enters the eye. The iris, where it is not covered by the sclera, reveals the choroid’s pigmentation, usually brown, blue, gray or green giving the eye its color. Within the iris, there are two sets of smooth muscles. The inner set is circular and serves to constrict the inner edge of the iris, the pupil. The other set is perpendicular to the circular muscles and serves to dilate the pupil. Behind the iris is the lens, a transparent, elastic, but solid ellipsoid body that bends light rays, focusing them on the retina, the third tissue layer. The retina is a network of nerve cells, notable the rods and cones, that send impulses along the optic nerve to the brain. The rods provide vision in dim light, while the cones respond best to bright light and provide color vision. The shape of the eye is maintained by the anterior chamber filled with semi-liquid aqueous humor, which is produced by the ciliary body, the posterior segment of the eye filled with transparent jelly (Fig. 2)

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Eye Muscles The movement of the eyes are controlled by the six extra ocular muscles. These muscles originate on the bones of the orbit and insert on the eyeball itself. Three pairs of striated extra ocular muscles are responsible for each movement. Four of the muscles are attached to the superior, inferior, medial, and lateral surfaces of the eyeball and are named accordingly: superior rectus, inferior rectus, medial rectus and lateral rectus. They cause the eyeball to turn up, down, inward, outward, respectively. The two remaining muscles are called superior and inferior obliques and they act alone to rotate the eyeball. (Fig. 3)

Fig. 3 Extraocular muscles of the eye

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How the Eye Works Your eyes and brain work together to make it possible for you to see. Light is reflected from objects onto the front surface of your eye, the cornea. The cornea bends the light, which then passes through fluid called the aqueous humor, through the pupil, and to the lens. The lens, which can change its shape, helps to focus light onto the retina at the back of the eye. On the retina, light forms an upside-down image on the cones and rods, the light sensitive receptors in the eye. The cones and rods send images to the brain via the optic nerve. Shortly after leaving the eye, the optic nerves from each eye cross and separate, sending their fibers to receiving and analytical stations in the brain. In effect, the brain receives messages from both eyes. Besides interpreting the visual input, if movement of both eyes is coordinated, the brain fuses images from each eye together to form one three-dimensional image.

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Common Sight Problems Visual Acuity Normal (Emmetropia)

Sight - Objects appear clear from a distance of 20’ (or 6 meters) and at reading distance. Cause - Lenses of the eye can change shape, for the purpose of converging light rays on the retina at the back of the eyeball, also called ‘accommodation’. This capability enables clear vision at close range.

Refractive Errors

Farsightedness (Hypermetropia)

Nearsightedness (Myopia)

Astigmatism

Sight - Difficulty seeing up close. In some cases, difficulty seeing at a distance. Cause - Eyeball is either shorter or smaller than average. Not a disease. Light rays do not converge at retina but rather at an angle that converges in back of retina. Corrective lenses – If only farsighted correction is needed, then spherical lenses will correct the refractive error. If patient is farsighted plus astigmatic, then compound lenses are needed. Compound lenses combine both spherical and cylindrical correction.* Sight - Difficulty seeing at a distance. Cause - The eyeball is longer or larger than average. Not a disease. Light rays converge in front of the retina, rather than on the retina. Corrective lenses – If only nearsighted, then a spherical lens will correct. If patient is nearsighted plus astigmatic, then compound lenses containing both spherical and cylindrical corrections are needed. * Sight - Difficulty seeing some objects while other objects are seen clearly. Difficulty seeing objects near and far. Cause –Non-round cornea results in uneven refraction of light. Corrective Lens –Cylinder. When patient is either near or farsighted then compound lenses will be used that combine cylindrical and spherical correction. *

Other Problems

Presbyopia

Binocular Misalignment (Strabismus) Color Vision Deficiency

Sight – Difficulty seeing objects placed near the eye Cause – Loss of elasticity of the focusing lens inside the eye (loss of accommodation), commonly begins when patients reach their 40’s. Corrective Lens –If correction needed for reading or close work only, then magnification will be added to a spherical lens. When patients have blurred distance vision in addition to presbyopia and want to wear glasses for both near and distance vision, then bifocals will be prescribed. Sight –Double vision or suppressed vision in one eye. Cause – Poor coordination of muscles that move the eyes or inability to fuse images from two eyes. Corrective Techniques –Vision training, glasses with prism components, surgery. Treatment before age six is important. Sight – Inability to see some colors, most commonly red and green. Cause – Usually genetic in origin. Affects 1 out of 8 males and 1 or 30 females. Corrective Techniques – none unless due to either pathology or medication.

*When compound lenses are not available, then spherical lenses may be substituted which contain an additional correction beyond the amount required to correct the patient’s nearsightedness. See “Using Spherical Equivalent” in Module 6. 9

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Professional Eye Exams Recommended Schedule Children

Adults

• • • • • •

Infants - Shortly after birth and again at six months Starting at age 4 or 5 – every year Also, when parent suspects eye related problems Adults with good general health - every two or three years Patients over 50 - every year Patients with risk factors for diabetes, glaucoma, cataracts –every year

Benefits Address health problems • •

•

Early detection of eye conditions which are treatable if addressed in time. Ex. Amblyopia, also called lazy eye, can be treated up to the age of six. Early detection of other health conditions of which the patient may not be aware. Ex. Diabetes and Glaucoma. Although there are no cures for these conditions at present, the patient can take steps to prevent blindness by adopting a regimen of medication and other strategies in partnership with medical personnel. For chronic conditions involving either the eye or general health, the exam provides patient with feedback, support, and treatment, if applicable, for managing the condition.

Provide clear vision using corrective lenses • •

Refractive errors –Exams are used to measure the patient’s refractive errors and, if needed, to prescribe the lenses required to correct blurred vision. Refractive errors are not due to disease but rather the shape and size of the eyeball. Presbyopia –Exams are used to detect if the patient’s ability to see objects up close is decreasing. Presbyopia is common starting around age 40. When corrective lenses for Presbyopia are combined with corrective lenses for farsightedness, the glasses are called bifocals.

Learn how to ensure eye health and safety •

Learn strategies that protect the eyes such as good nutrition, good hygiene, protection from UV rays, and injury prevention.

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Module 2 – Vision Assessment Protocol for Primary Eye Care Examination* When to Use:

1

Review Patient History

• • • • • •

Record patient history on Patient Record form. Determine time of last professional eye exam. Ask patient if he/she is taking any medications Ask patient if he/she has concerns or questions.

•

• •

Check distance vision and near vision. See procedures on pages 16-17. Record results on Patient Record form. If both distance AND near vision are clear (20/30 or better for distance vision), then skip step 4 with adult patients. In the case of children, include step 4 in all exams. Children have a strong ability to focus their eyes and yet may have refractive errors that could be corrected with lenses. If either distance OR near vision is blurred (worse than 20/30 for distance vision), then conduct pinhole test on page 19 and record. If vision improves during pinhole test, be sure to include step 4 If vision does not improve, skip step 4.

• 2

Examiner is assessing vision in a Vision Station, at a health center or in the field. Examiner may be trained to perform basic first aid.

Assess Visual Acuity •

3

Screen for Binocular Dysfunction

• •

Cover Test and Versions Test. See pages 20 and 21 Record results on form.

4

Measure Refractive Errors

•

® Use FOCOMETER to determine eyeglass prescription needed, if any. For correcting refractive errors, including astigmatism, see pages 30 and 31. Record results on form.

•

Check all eye and surrounding structures for evidence of disease or trauma. See Module 4, “Eye Injuries and Diseases”. Screen for color vision defects. Procedure on page 23. Examine nape of neck for Acanthosis Nigricans (Type II Diabetes). Procedure on page 24. If problem(s) is identified, then record on form and refer.

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Check eye for disease or injury

• • •

6

Give eye health and safety information

7

Make referral as needed

•

Provide information on hygiene, nutrition, UV protection, and injury prevention. See Module 3, “Eye Health and Safety.”

•

Review “Criteria for Referring Patients to Eye Care Professional” and make a referral if any of the criteria is met. See Module 5, “Referrals”.

. •

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Wrap-up Interview

• •

Review findings of exam with patient. If giving a referral, give patient the reason. Discuss the patient’s concerns and questions. Schedule next appointment with patient. Encourage patient’s family and friends to make appointments. (See schedule recommendation on page 11.) Complete “Patient Record” form and retain in patient files.

*In the United States, prescriptions for corrective lenses can only be filled if written by either an optometrist or ophthalmologist. InFOCUS advises anyone providing vision services to respect all regulations applicable to the area in which services are provided. 13

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Visual Acuity Charts •

Use standardized charts to measure visual acuity. Two charts commonly used to measure distance vision are the Snellen chart and the Tumbling E chart shown below. Both are available through InFOCUS.

•

Visual acuity is measured in terms of the “Snellen Fraction” named for the physiologist who invented it. The fraction “20/20” denotes normal or average vision. • The number above the dividing line represents the testing distance of 20 feet (equivalent to 6 meters). • The number below the dividing line indicates the number of feet at which a line of letters can be seen by persons with normal vision.

Example: Individual has 20/40 visual acuity. Individual was tested at 20 feet from chart however the smallest line of letters he/she could read was the line marked 40. Persons with normal vision could read that same line at 40 feet. Tumbling ‘E’

Snellen

Includes red and green lines that give clues regarding patient’s color perception.

Useful with patients who do not recognize the letters of the alphabet Actual size: 21½” x 11½”

Actual size: 21 ½” x 11 ½”

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Procedure: Measuring Distance Vision Purpose: Illumination: Target: Distance: Lenses: Equipment: Form: Instructions to Patient:

Steps:

1. 2. 3. 4. 5. 6.

To determine the smallest line of letters the patient is able to read at a specified distance with each eye. Children, starting at age 4, can take this test as well as adults. Make sure the eye chart is well lit and no reflection is coming off the chart. Snellen Chart (Ex. Letters, Tumbling E, numbers, pictures, Landolt C). See examples on page 15. 20’ or 6 meters from chart to patient Patient first reads chart without corrective lenses. Test is repeated with patient wearing corrective lenses as needed. Opaque Occluder Patient Record form and pencil to record results If patient is wearing prescription glasses, then ask him/her to take them off. Explain to patient that you will indicate the letters (numbers, Tumbling E’s, etc.) on different lines of the chart one at a time. He/she should tell you what they see. In the case of Tumbling E charts, it is helpful to give the patient a large cut out letter “E” and ask them to respond by turning the letter to match the direction of the letter they see on the chart. (This method works well when the examiner and patient do not speak the same language.)

Test right eye first. Cover left eye with occluder. Be sure that patient is using only the right eye. Test vision by starting with the largest letters first. Proceed down the chart to the smallest letters the patient can see. It is advisable to skip lines so as to identify the smallest line that the patient can read. Record the smallest line in which the patient can see at least half of the letters. See Record section below. Repeat the test with the left eye. Repeat the test with patient wearing his/her corrective lenses. If patient cannot see largest letters, then follow the procedure in Notes section.

Interpretation of Test Results:

• Normal Vision: 20/30 or better* • Blindness: 20/400 or less

• Subnormal Vision: worse than 20/30

*Patient may benefit from glasses, if available. 20/30 or better is an “acceptable” level of visual acuity but with the proper resources vision may still be improved. Notes: If the patient cannot read the largest letters, then use the following test sequence. Failure at one level of the test requires testing at the next level. 1. Ask the patient to walk toward the chart and report when the largest letter is legible. The distance from the chart would be the number of the acuity fraction, i.e. 3/400. 2. The patient is seated and asked to count the examiner’s hand. Record as “finger counting at 3 feet.” 3. Ask the patient to tell whether the examiner’s hand is moving or still. Record as “hand movement at 3 feet.” 4. The patient is asked to indicate whether a light source is on or off. If the patient is accurate, it is recorded as “light perception”; if not, “no light perception.” Record: The patient’s visual acuity is measured for the right eye, left eye and both eyes. Visual acuity is recorded in one of the following ways: 1. Smallest line patient can read at least half of the letters along with number of letters missed on that line. Ex. 20/40 –2 --or-2. Smallest line patient can read completely, along with the number read correctly on that next line. Ex. 20/20 + 2 i.e. patient can read all the letters on the 20/20 line and can also read 2 letters on the 20/15 line. So credit is given for the 2 letters read on the line below the 20/20 line.

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Procedure: Measuring Near Vision Purpose:

To assess visual acuity using objects at a reading distance. This procedure is used with adults and children, starting at age 4. Make sure the eye chart is adequately lit and that no reflection is coming off the chart. Near Point Card (Reduced Snellen chart) or usual reading material. Young children may require a card with symbols (drawings of animals etc.) without letters. 14” - 16” or normal distance for patient to use when he/she reads or works at close range First test without corrective lenses and then with corrective lenses. Opaque Occluder Patient Record form and pencil to record results. If patient is wearing corrective lenses, then ask him/her to take them off. Ask patient to read the Near Point Card (Reduced Snellen chart) or reading material at 14” – 16” with one eye at a time, then with both eyes. Repeat wearing glasses. (Hyperopes, persons with blurred near vision, cannot see close without them.)

Illumination: Target: Distance: Lenses: Equipment: Form: Instructions to Patient:

Steps: Using Near Point Card 1. Test right eye first. Cover left eye with occluder. Be sure that patient is using only the right eye. 2. Test vision by starting with the largest letters first. Proceed down the chart to the smallest letters the patient can see. It is advisable to skip lines so as to identify the smallest line that the patient can read. 3. Record the smallest line in which the patient can see at least half of the letters. 4. Repeat the test with the left eye. 5. If patient wears corrective lenses, have patient wear glasses and repeat steps 1 – 4. 6. Record results on Patient Record form. Using Other Targets 1. Same as above 2. Test vision by asking patient to hold target at range in which material is clear. 3. If patient reports that he/she cannot clearly see target at any range when holding the target, then record on the form that patient needs magnification lenses to see at near. 4. If patient reports that he/she can see target clearly, ask patient to demonstrate the distance(s). Record on the form the smallest line seen clearly on the Near Point card Interpretation of Test Results:

When using the near point cardNormal Vision = 20/20 Subnormal Vision: Less than 20/20 depending on age

When using reading material normal = able to see familiar reading material without magnification When using non reading material normal = able to see target at reading distance (approx. 14”-16)

Notes: Nearsighted patients will generally see better at near without glasses. Farsighted patients have difficulty seeing up close or cannot see at all up close without their glasses. Therefore, patients should be tested both with and without their glasses. Presbyopes who are also myopic may be able to see clearly at near while not wearing their prescription for distance. 17

Near Vision Assessment The smallest type (4.5 pt. type) on a near point card should be seen clearly through the individual’s prescription glasses, or without glasses for those with 20/20 vision, when the card is viewed at 14 inches in moderate lighting conditions. In order to see the small type clearly, older adults may need to increase the distance between the eyes and the card, or use magnification (plus power lenses). Plus lenses may be an “add” applied to the distance prescription with bifocal eyeglasses, or reading glasses may be indicated for those not needing a distance prescription. To find the appropriate power of lenses to dispense to adult patients, refer to the section ‘Protocol for Dispensing Reading Glasses’ in this manual. For children, dispense the lowest power of lenses that offer the best clarity when the card is viewed at 14 inches. This near assessment is especially important for children who are suspected to have difficulty reading or seeing up close (hyperopes). A children’s near vision card with symbols is used for those who cannot read letters or words, (Fig. A). The smallest line is equivalent to 20/30 near vision at 14 inches, which should be sufficient for good reading performance in school. Note that children with astigmatism may also have difficulty reading small print, unless the astigmatism is corrected with cylindrical lenses.

Figure A (Example of children’s near point card. This example lacks clarity due to the photocopying process. Not intended to use with patients.)

Not actual size Figure B Example of Near point card (side A)

Figure C Example of Near point card (side B)

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Procedure: Pinhole Occluder Test Purpose:

To determine if patient’s visual acuity would be improved using corrective lenses. Improved sight when viewing through the occluder indicates patient would benefit from corrective lenses.

Illumination:

Make sure the eye chart is well lit and that no reflection is coming off the chart.

Target:

Standard acuity chart such as Snellen, Tumbling ‘E’, etc.

Distance:

20’ or 6 meters

Lenses:

Read without corrective lenses. Repeat wearing corrective lenses.

Equipment:

Pinhole occluder

Form:

Patient Record form and pencil to record results

Instructions to Patient:

If patient is wearing prescription glasses, then ask him/her to take them off.

Steps: 1. Test right eye first. Cover left eye with cardboard or cup. Ask patient to read a line on visual acuity chart such as Snellen or Tumbling ‘E’. Ask patient if his/her sight is the same through the occluder. •

If improved, then patient could probably benefit from corrective lenses.

•

If not improved, then patient would not benefit from corrective lenses.

2. Test left eye. 3. Repeat steps 1 and 2 wearing corrective lenses. 4. Record results on Patient Record form.

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Procedure: Screening for Binocular Dysfunction (Cover / Uncover Test)

Purpose:

To observe how well the eyes work together. Early detection and treatment of problems with binocular coordination can prevent amblyopia (reduced visual perception). The test for binocular vision is called the Cover/Uncover Test. This test should be performed after the visual acuity test.

Illumination:

Ordinary room light

Target:

Standard acuity chart such as Snellen, Tumbling ‘E’, etc.

Distance:

20’ (or six meters) from patient to acuity chart

Lenses:

Patient wears corrective lenses, if applicable

Equipment:

Acuity chart such as Snellen or Tumbling ‘E’

Instructions to Patient:

When asked, fixate on target, don’t move head and don’t look away.

Steps: Cover/Uncover Test 1. Test right eye first. The patient is asked to look at the target, the large “E” on top line of the acuity chart at 20’ and maintain fixation with both eyes. 2. The left eye is then covered while telling the patient not to lose fixation with the uncovered (right) eye. The right eye is observed for movement. 3. Note if any movement is detected, and if possible, indicate whether the movement is consistently towards the nose, or towards the ear. 4. Test the left eye. Repeat steps 1 –3 with the right eye covered and look at possible movement in the left eye. 5. Then repeat for each eye using the near target (examiner’s nose at a distance of 3’ to 5’). 6. Any movement of either uncovered eye should be recorded on form and a referral should be made to an eye doctor for full assessment of binocular function. 7. The examiner records “pass” or “fail” on Patient’s Record form, and those who fail are referred for a complete eye exam.

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Procedure: Screening for Coordinated Eye Movement (Versions Test)

Purpose:

To observe how well the eyes work together. Early detection and treatment of problems with binocular coordination can prevent amblyopia (reduced visual perception). The test for coordinated eye movement is called the Versions Test. This test should be performed after the visual acuity test.

Illumination:

Ordinary room light

Target:

Standard acuity chart such as Snellen, Tumbling ‘E’, etc.

Distance:

Versions – 3’ to 5’ from patient

Lenses:

Patient wears corrective lenses, if applicable

Equipment:

Acuity chart such as Snellen or Tumbling ‘E’

Instructions to Patient:

When asked, fixate on target, don’t move head and don’t look away

Steps: Versions Test 1. The patient is asked to look at the examiner’s finger and follow the finger with both eyes without moving the head as a wide rectangle is traced through the air. For children, use a puppet. 2. The examiner watches the patient’s eyes, to ascertain that both eyes follow the finger and work together throughout the sideways and up and down movements. 3. Refer to appropriate eye professional if eyes don’t follow together. 4. The examiner records either “unrestricted” or “restricted” on Patient’s Record form.

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Procedure: Screening for Limitations of Visual Field Purpose:

To assess whether limitations are present in the field of vision

Illumination:

Ordinary room light

Target:

Standard acuity chart such as Snellen, Tumbling ‘E”, etc.

Distance:

1 to 2 feet from patient’s head

Lenses:

Patient does not wear corrective lenses

Equipment:

Not applicable

Instructions to Patient:

Ask patient to report when fingers are seen and how many fingers are visible

Steps: 1. Test right eye first. Tell patient to close or cover left eye. Patient stares straight ahead to the large letter at the top of the acuity chart. 2. Examiner places one of his/her hands behind the patient’s head. With either one or two fingers showing, the examiner brings his/her hand around the side of the patient’s head to the front. 3. Patient reports when the number of fingers is visible and the number seen. 4. Examiner repeats the same movement on the other side of patient’s head. The movement is repeated two more times •

over patient’s head

•

under patient’s head

In this way, each quadrant of the patient’s potential field of vision is tested, one quadrant at a time. 5. Repeat with left eye. 6. Record any difficulties with visual field on Patient Record form. If found, refer to an eye doctor for a full assessment.

22

Procedure: Screening Color Vision Purpose:

To determine whether a complete color vision assessment is necessary.

Illumination:

Ordinary room light

Target:

Color Vision test plates

Distance:

Near, about 14” to 16”

Lenses:

Patient wears corrective lenses, if applicable

Equipment:

Color vision test plates

Instructions to Patient:

Read numbers or letters on test plates and tell examiner

Steps: 1. Patient is instructed to inspect various standardized color vision plates and respond to examiner’s questions. 2. Examiner asks the patient to say the number or letter seen. 3. If patient makes one or more errors in reading plates or any complaint about color vision, then refer to eye doctor for complete examination. 4. Examiner records either “pass” or “refer” on Patient’s Record. Notes: Color Vision Plates Color vision plates may be ordered from any ophthalmic supply firm. Request pseudoisochromatic plates for testing color perception. Care should be taken when handling the plates so that they are not smudged with fingerprints. If Color Vision Plates are not available, test whether the patient correctly identifies the red and green lines on the Eye Chart. Red-green color deficiency is the most common type of color blindness. Causes of Color Blindness Color blindness is usually caused by a genetic defect in the cone cells in the retina. If color blindness is detected in only one eye, then cause may be pathology instead of genetics. If color blindness develops, the cause may be medication the patient is taking.

23

Procedure: Screening for Acanthosis Nigricans Purpose:

To detect early symptom of Type II Diabetes Mellitus, a major cause of blindness

Illumination:

Moderate

Instructions to Patient:

Explain to patient that the back of the neck will be examined.

Steps: 1. Look at the nape (back) of the patient’s neck for a darkened band. 2. Distinguish between birthmarks and Acanthosis Nigricans, which has a raised velvety texture. 3. If Acanthosis is present, alert the patient that this mark is often an early sign of Type II Diabetes. Encourage patient to see a doctor to learn how to manage the disease and prevent blindness. Patient should also have their eyes examined regularly by an eye professional. 4. Examiner records either “pass” or “refer” on patient’s record. Note:

See Diabetic Retinopathy in the Module 4, “Eye Injuries & Diseases”. This darkened band is often mistaken for a birthmark or dirt.

24

Measuring Refractive Errors using the FOCOMETER® Fact Sheet The FOCOMETER® was developed by Drs. Ian Berger and Larry Spitzberg at the University of Houston College of Optometry in Houston, Texas to provide a subjective refraction without the need for electricity or complicated protocol. The portable, hand-held instrument is highly appropriate for use in poor and remote areas. Based on Badal optics, the FOCOMETER® allows the patient to view a real unmagnified target and bring it into focus, with a direct reading of spherical correction on a linear diopter scale. Measurement of cylinder for stigmatism is easily accomplished, utilizing a ‘clock’ target supplied with the instrument. ‘Add’ power requirements for presbyopes can also be measured, simply by first obtaining the distance correction and then adding plus power in small increments until a target at the desired ‘near’ distance is clear. In extensive field-testing, the FOCOMETER® was found to be as accurate as other methods of subjective refraction and retinoscopy. Field test data were published in Optometry and Vision Science (April 1993). The FOCOMETER® is patented and is registered with the F.D.A 510(k)

Utilized in over 40 countries, the FOCOMETER® is manufactured by InFOCUS, a non-profit organization based in Houston, Texas. The design eliminates the need for many pieces, which could be lost or broken and difficult to replace. Many clinicians in the USA and other developed countries find the FOCOMETER® useful for over-refraction of contact lens wearers and for patients ordinarily difficult to refract, such as patients with keratoconus. Contact InFOCUS to order a FOCOMETER®, to learn about donating FOCOMETER® to a colleague in a developing country, or with any questions that you may have about the FOCOMETER® or primary eye care.

25

How to Read the FOCOMETER® The FOCOMETER® provides a readout of spectacle prescription. • •

•

Prescriptions are measured in units called diopters. See Glossary in Appendix for a description. A diopter scale is found on the threaded barrel of the FOCOMETER®. The scale is calibrated and linear. The range of the scale is +10 to –10. Note only even numbers are printed on the barrel. • A reading of 0.00 indicates that the person has no refractive error. • The plus (+) or minus (-) sign in front of the numbers represent the power of the plus lens or minus lens needed to correct the refractive error of the patient. • Plus correction improves farsightedness or Hyperopia. • Minus correction improves nearsightedness or Myopia. The rotating collar of the FOCOMETER® contains four equally spaced lines with three dots between each line. The lines represent whole diopters and the dots represent quarter and half diopters. Note: Some models do not have dots on the scale, only straight lines indicating whole and half diopters.

To take a reading…. • •

•

Threaded barrel

Stationary collar

Look Through This end

Lens (front)

Calibrated Linear scale

Flexible eye piece

Rotating collar

Side view

The reading should be measured to the nearest quarter on the diopter scale. To take a reading, look straight down on the diopter scale. The reading is taken on the diopter scale where the collar crosses the diopter scale. Patients are instructed to stop rotating the collar as soon as the clock target is clearly seen through the FOCOMETER®. • When a straight line on the collar is found directly above the diopter scale on the barrel, then the diopter reading is a whole number. ex. –2.00, 0.00, or +1.00 • When a dot on the collar is found directly above the diopter scale, then the diopter reading will include a quarterly fraction of a diopter. ex. –2.25, -2.50, or -2.75

See examples on next page.

26

Examples of FOCOMETER® Readings Where barrel and collar meet… Ex.

Collar covers scale

Collar at the scale shows

Then reading is…

1

At –2 mark

Line (indicates a whole number)

-2.00

2

Slightly past –2, between –2 and -3

Dot next to line (indicates a quarter diopter)

-2.25

3

Between 0.00 and – 1.00, at slightly less than -0.50 diopters

Middle dot between lines (indicates half a diopter)

-0.50 (rounded to closest quarter based on collar)

27

Procedure: Using FOCOMETER® for Refractive Error (sphere) Purpose:

To determine the patient’s refractive error, if any, and thus identify the prescription needed to correct the refractive error.

Illumination:

Make sure the eye chart is well lit and no reflection is coming off the chart.

Target:

Standard Clock Chart

Distance:

20’ or 6 meters from chart to patient

Lenses:

Read chart without corrective lenses. Repeat the test wearing the patient’s new prescription glasses.

Equipment:

FOCOMETER®, tripod (optional), Opaque Occluder

Form:

Patient Record form and pencil to record results

Instructions to Patient:

If patient is wearing prescription glasses, then ask him/her to take them off. Explain to patient that the FOCOMETER® is used to test one eye at a time. The eye being tested looks through the FOCOMETER® at the target while the other eye is covered. Demonstrate how to hold the FOCOMETER® up to the eye, point at the clock chart and rotate collar. Emphasize that patient should STOP rotating as soon as target is clearly seen.

Steps: 1. Test Right Eye First - Adjust FOCOMETER® to full plus position, i.e., fully extended. The patient views the clock target through the FOCOMETER® using right eye, left eye covered with cardboard or cup, and rotates the collar to the patient’s right. As soon as either all or one of the radials on target is clear, the patient stops turning the collar. The examiner asks what the patient has seen. •

If all radials on the clock target enter focus at the same time, the patient does not have astigmatism in that eye. Mark “no” astigmatism on the patient record form. The patient requires only a spherical lens. Read the diopter scale on the FOCOMETER®. Record the diopter reading for the right eye on the patient record form. Then proceed to step 2.

•

If one or two radials enter focus before the others, then the patient has astigmatism and requires a lens with axis and cylinder. Stop this procedure. Mark “yes” for astigmatism on the patient record form.

2. Test Left Eye Second – Repeat Step 1. 3. Test Right Eye Again – Repeat Step 1. If results differ from first time, repeat again. Example:

Record the exact diopter reading for each eye on the patient record form. See example below. Example: Hyperopia (far sighted) R.E.

28

+2.00D

L.E.

+2.25D

Interpretation of Test Results:

0.00 diopters - Normal vision, no need for corrective lenses Plus diopters - Far vision correction available with prescription lenses Minus diopters - Near vision correction available with prescription lenses All radials appear at same time - only spherical lenses needed, no astigmatism present One or two radials appear first - astigmatism present

29

Procedure: Using FOCOMETER® for Astigmatic Error Purpose:

To determine the patient’s astigmatic error, if any, and thus identify the prescription needed to correct the astigmatic error.

Illumination:

Make sure the eye chart is well lit and no reflection is coming off the chart.

Target:

Standard Clock Chart

Distance:

20’ or 6 meters from chart to patient

Lenses:

Read chart without corrective lenses. Repeat the test wearing the patient’s new prescription glasses when they become available.

Equipment:

FOCOMETER® tripod (optional), Opaque Occluder

Form:

Patient Record form and pencil to record results

Instructions to Patient:

Tell patient to look through FOCOMETER® at the clock chart while the other eye is covered. Instruct patient to turn FOCOMETER® collar to the right and then STOP as soon as the first radial comes into view. Once the reading is taken, the patient should resume viewing through the FOCOMETER® and continue rotating the collar UNTIL the second radial, perpendicular to the first, comes into view. For example, If the first radial seen clearly is 11 - 5 line on the clock target, tell the patient to continue rotating the collar until the 8 - 2 line on the clock target is seen clearly. Make a note of the reading on the FOCOMETER®.

Steps: 1. Complete Steps 1 and 2 of “Using FOCOMETER® for Refractive Error”. If patient reports that one or two radials become clear before the rest of the radials, then proceed with this procedure. 2. Test Right Eye First - Adjust FOCOMETER® to full plus position, i.e., fully extended. The patient views the clock target through the FOCOMETER® using right eye, left eye covered with occluder, cardboard or cup, and rotates the collar to the patient’s right. •

As soon as one of the radials on target is clear*, the patient stops turning the collar. The examiner asks the patient which radial(s)* were seen first. The examiner records the number of degrees (30 to 180 degrees) associated with the radial. In addition, the examiner records the number and sign of diopters on the barrel of the FOCOMETER®. This first radial is called the Spherical correction. Ex. First Radial (Spherical) +3.00 D @ 150 degrees

30

•

The examiner tells the patient to stop as soon as the second radial* comes into focus. Then the patient looks through the FOCOMETER® again, and continues to rotate the collar to the right until the second radial, perpendicular to first radial, comes into focus. This second radial is always 90 degrees away from the first and always has a diopter reading that is in the more minus direction on the scale than the first radial. The examiner records degrees and diopters again. Ex. Second Radial +2.50 (diopters) @ 60 (degrees)

3. Calculate the Cylinder required to correct astigmatism by finding the difference in diopters between the first and second perpendicular radials Ex. (First Radial) +3.00 minus (Second Radial) +2.50 = 0.50 (recorded as -0.50D) 4. Prescription for this eye is written as: +3.00 - 0.50 (sphere)

x

060

(cylinder) (axis) (degrees)

+3.00 is 3.00 diopters of Sphere from first radial reading -0.50 diopters is the cylinder power from the difference between the powers of the two radials 60 degrees is the axis of the perpendicular (second) radial 5. Test Left Eye Second – Repeat Steps 2 – 4. More examples: Ex. #2 1st Radial is -2.00 @ 90 (12 o’clock) 2nd Radial is -4.00 @ 180 (3-9 o’clock) -2.00 minus -4.00 = -2.00 Then the cylinder is -2.00 Rx is written as -2.00 - -2.00 x 180 (sphere)

-

(cylinder) (axis) (degrees)

Ex. #3 1st Radial is +1.00 @ 120 (1 o’clock) 2nd Radial is -3.00 @ 30 (10 o’clock) +1.00 minus -3.00 = -4.00 Then the cylinder is -4.00 Rx is written as +1.00 - -4.00 x (sphere)

-

Ex. #4 1st Radial is 0.00 at 180 (3-9 o’clock) 2nd Radial is -2.00 @ 90 0.00 minus -2.00 = -2.00 Then the cylinder is -2.00 Rx is written as plano - -2.00 x (sphere)

030

(cylinder) (axis) (degrees)

090

- (cylinder) (axis) (degrees)

31

Remember the Scale – You always turn the Focometer sleeve to get the cylinder power in the more minus direction Sphere power is always the most plus direction

+10 +9 +8

+7

+6

+5 +4

+3

+2

+1

0

-1

-2

-3

-4

-5

-6

-7

-8

-9

-10

Cylinder power is always the more minus direction

Prescriptions are always written in the minus form so we can only go in one direction from most plus to minus. In the examples above:

Ex. 1 Ex. 2 Ex. 3 Ex. 4

Sphere reading on Focometer +3.00 D -2.00 D +1.00 D 0.00 (pl)

Cylinder reading on Focometer +2.50 D -4.00 D -3.00 D -2.00 D

Cylinder Power -0.50 D -2.00 D -4.00 D -2.00 D

Plug these numbers on the scale above and see how we derived the cylinder power. The above scale is the same as on the Focometer except that this scale is flat on a piece of paper instead of a tube. *If two radials become clear at the same time, then it is okay to estimate the radial between them. Eg. If both the 10 o’clock line and 11 o’clock line look equally clear then the axis will be between 30° (10 o’clock radial) and 60° (11 o’clock radial) which is 45° Interpretation of Test Results: All radials appear at same time. Normal vision, no need for astigmatic correction One or two of the radials appear at the same time - Astigmatic vision Record:

Record readings for each eye on Patient Record form. Sphere in diopters with plus or minus sign Cylinder in minus diopters and axis of cylinder in degrees Ex. R.E. +2.75 -2.00 x 120 L.E. +3.00 -2.25 x 150

32

Clock Target •

A standard chart used to assess refractive error. The clock target is available through InFOCUS.

•

The chart consists of six radials representing the degrees of a circle.

•

For purposes of identifying radials, only the radials marked 0 through 180 degrees are used.

•

0 and 180 is the same radial and may be recorded using either number.

•

Patients view the clock target through the FOCOMETER® at a distance of 20 feet.

•

•

If all of the radials come into view at the same time, then the patient has no astigmatic error.

•

If one or two of the radials come into view first, then the patient has astigmatic error.

Actual size is 11” x “17

33

FOCOMETER® Care and Maintenance

Cleaning

Lenses can be cleaned with a moistened soft cotton cloth and then wiped dry. The rubber eyepiece is purposely removable. It can be washed with soap and water, even between patient use. This is recommended if a patient has an eye infection.

Storage

Store FOCOMETER® in a closed container. Keep as dry as possible in humid weather. Condensation inside the unit, however, will clear up rapidly if the FOCOMETER® is place near a dry heat source (e.g., an electric light bulb.)

Maintenance

Other than keeping the instrument clean, no maintenance is necessary.

Repairs

It is possible to open the FOCOMETER® by first removing the three Philip’s screws found on the rubber eyepiece end of the unit. EXTREME CARE IS NECESSARY WHEN OPENING THE FOCOMETER® TO AVOID TOUCHING ANY LENS OR PRISM WITH BARE FINGERS, as fingerprints will become visible through the optical system. Wear clean, soft cotton gloves. Other screws for fastening prism mounting brackets and an annulus will be visible so that access if possible to all optical components for cleaning. Be careful not to damage the mirrored surface on the large prism.

Lubricating Collar

Lubricating the rotating collar screw mechanism is generally not necessary, but if the FOCOMETER® becomes stiff, a drop of petroleum jelly or very light oil can be gently rubbed along the grooves, taking care not to touch or smear the lenses.

34

Module 3 – Eye Health & Safety Preventive Practices Many of the problems that affect the eyes are preventable by practicing appropriate hygiene, good nutrition and basic preventative steps. Prevention is directly related to people’s behavior and the choices they make in how they live their lives. Good health education can lead to making healthier behavior choices.

Hygiene

Risk – Eye infections and maternal gonorrhea. Note: Maternal gonorrhea is a venereal disease; blindness in the newborn is prevented with antiseptic or antibiotic therapy. Preventive Steps – Do not share: towels, handkerchiefs, bandannas, bed pillowcases and linens, or cosmetics Wash hands: prior to and after touching the eye or playing with children Do not wipe sweat from eye using work shirts or other work clothing to prevent exposure to dust, pesticides and contaminants. Face Washing: frequent washing of face will discourage face-seeking flies which carry trachoma in many parts of the world. Household: Proper disposal of rubbish and feces and moving livestock away from houses will reduce the number of flies. Entire family needs to cooperate regarding household hygiene.

UV Protection

Risk - Excessive and unprotected exposure to ultraviolet (UV) radiation may contribute to or worsen Pterygium, cataracts and macular degeneration. Preventive Steps – Wear sunglasses or safety glasses with 100% UV blockage and wide brim hat

Injury Prevention

Nutrition

Risk – Burns that damage cornea are caused by household cleaners, pesticides, fungicides and fertilizers. Also debris in the eye, traumas to the head and infections resulting from traumas. Preventive Steps – Use safety equipment properly: • Wear ANSI-approved, impact-resistant safety glasses or work goggles • Use 100% Ultraviolet blockage sunglasses or goggles • Use well fitting cap with a strong brim • Stay alert and do not using audio equipment that hinders hearing Risk – Vitamin A deficiency leads to night blindness, dry eyes, and pain in the eyes. Vitamin A deficiency is the leading cause of non-infectious blindness in children worldwide. Deficient diets also impair healing and recovery from injuries and infections. Preventive Steps - Eat foods rich in Vitamin A such as red, yellow, and green vegetables, fruits and diary products. Eat a well balanced diet overall, including an adequate daily intake of protein. Diabetics should eat foods recommended to manage their disease.

35

Basic Primary Eye Care Techniques How to make and apply an eye bandage (patch) It is often necessary to cover a person’s eye before sending him or her to a hospital or to a physician. Other times it is necessary to change the bandage for a person who has had an operation. What should you do? 1. Do not touch the eye with your hands 2. Wash your hands very well with soap and water 3. To cover the eye, use sterile gauze or a very clean cloth cut in a 2 ½ inch (6 centimeter) square 4. Place 2 or 3 small squares over the eye, and tape them as illustrated in the drawing 5. Before applying the dressing, ask the patient to close both eyes, so he or she does not move the gauze or tape.

How to make an eye shield

36

How to evert (turn out) the upper eyelid

1. Look for the foreign body on the eyeball without lifting the upper eyelid 2. If you cannot find it, take the upper eye lid between the thumb and forefinger 3. Lift the eye lid so it stays on the match stick and with the entire conjunctiva in view, look for the foreign body 4. When you have found it, carefully remove with a clean cotton swab or the tip of a clean cloth

How to apply drops and / or ointment to the eye

Portions of this chapter, including illustrations, are adapted from ‘Primary Eye Care manual’, World Health Organization, Scientific

Publication No. 490 1985

37

38

Module 4 – Eye Injuries & Diseases Assessing Eye Conditions Eye injuries are common and a leading cause of preventable unilateral blindness worldwide. The causes vary, but drawing upon experience from The Gambia and Senegal, trauma is more common during the farming season and among small-scale metal workers working without eye protection. Stick injury is common in children and farmers, sometimes causing a penetrating injury that can result in the affected eye quickly becoming infected. Blunt trauma is common among children, who can be injured with a catapult or stone. The dusty environment is a common cause of corneal, conjunctival and sub-tarsal foreign bodies injuries. Injuries are often preventable which makes education at the community level important. Village health workers and community-based volunteers (such as ‘Nyateros‘ or ‘Friends of the Eye’ in The Gambia) are important promoters of good eye health practices. A network of community ophthalmic nurses can provide appropriate first aid and refer from village level to secondary or tertiary care. This can significantly reduce visual impairment and blindness resulting from injuries. Health facilities should be ready to deal with eye injuries by: • • •

ensuring that staff know how to assess eye injuries and perform basic first aid procedures appropriate to their level of training ensuring a supply of equipment, drugs and consumables required to assess and provide first aid for eye injury having a plan of how to refer patients, including nearest referral facilities, and options for transporting patients in an emergency.

The chart below provides an easy reference for community level workers faced with an eye injury in their clinic or community.

39

First aid management of eye injuries

Cause of injury Burns

Foreign body (FB)

Penetrating injury

Blunt injury

Lid laceration

Conjunctival, corneal or subChemical, thermal tarsal (under the or radiation upper eyelid)

Blood in anterior chamber (Hyphaema)

Laceration of lid Corneal or scleral margin or perforation canaliculus

Pain

Severe

Mild/moderate

Mild/moderate

Severe

Moderate

Vision

Reduced

Vision affected if central cornea involved

Reduced

Reduced

Normal

Light examination

FB seen on Red eye and hazy conjunctiva, cornea cornea or under lid

Variations

Cornea hazy and pupil may be Blood seen in distorted with anterior chamber. uveal prolapse. Pupil may be dilated Shallow anterior chamber

Laceration visible

Management First Aid

Foreign body (FB) Remove

Assess

Penetrating injury Urgent

Refer

or Refer

Refer

Refer

Immediately irrigate thoroughly with clean water with special attention to particles that may be trapped under the eyelid. Apply antibiotic eye ointment and refer to eye unit immediately

Remove with edge of clean cloth. If on cornea, gently use matchstick covered with cotton wool. Refer if embedded

Rest; refer if hyphaema is severe or no improvement with bed rest by day three. Analgesics must not contain aspirin

Refer immediately to an eye unit. Tetanus toxiod 0.5ml immediately

Burns

Blunt injury

Lid laceration Refer

Refer to an eye unit to ensure proper alignment of the lid margin. Tetanus toxoid 0.5ml immediately

Copyright & Disclaimer Accessibility © International Centre for Eye Health, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK 40

41

Most Common Eye Diseases Some eye problems are minor and fleeting. But some lead to a permanent loss of vision. Common eye problems include: • • • •

Cataracts - clouded lenses Glaucoma - damage to the optic nerve from too much pressure in the eye Retinal disorders - problems with the nerve layer at the back of the eye Conjunctivitis - an infection also known as pink eye

Your best defense is to have regular checkups, because eye diseases do not always have symptoms. Early detection and treatment could prevent vision loss. See an eye care professional right away if you have a sudden change in vision or everything looks dim or if you see flashes of light. Other symptoms that need quick attention are pain, double vision, fluid coming from the eye and inflammation.

Cataract A cataract is a clouding of the lens in your eye. It affects your vision. Cataracts are very common in older people. By age 80, more than half of all people in the United States either have a cataract or have had cataract surgery. Common symptoms are: • • • • • •

Blurry vision Colors that seem faded Glare Not being able to see well at night Double vision Frequent prescription changes in your eye wear

Cataracts usually develop slowly. New glasses, brighter lighting, anti-glare sunglasses or magnifying lenses can help at first. Surgery is also an option. It involves removing the cloudy lens and replacing it with an artificial lens. Wearing sunglasses and a hat with a brim to block ultraviolet sunlight may help to delay cataracts.

42

Glaucoma Glaucoma damages the eye's optic nerve. It is a leading cause of blindness in the United States. It usually happens when the fluid pressure inside the eyes slowly rises, damaging the optic nerve. Often there are no symptoms at first, but a comprehensive eye exam can detect it. People at risk should get eye exams at least every two years. They include • • •

African Americans over age 40 People over age 60, especially Mexican Americans People with a family history of glaucoma

Early treatment can help protect your eyes against vision loss. Treatments usually include prescription eye drops and/or surgery.

Diabetic Retinopathy Diabetes is a disease that occurs when the pancreas does not secrete enough insulin or the body is unable to process it properly. Insulin is the hormone that regulates the level of sugar (glucose) in the blood. Diabetes can affect children and adults. How does diabetes affect the retina? Patients with diabetes are more likely to develop eye problems such as cataracts and glaucoma, but the disease’s affect on the retina is the main threat to vision. Most patients develop diabetic changes in the retina after approximately 20 years. The effect of diabetes on the eye is called diabetic retinopathy. Over time, diabetes affects the circulatory system of the retina. The earliest phase of the disease is known as background diabetic retinopathy. In this phase, the arteries in the retina become weakened and leak, forming small, dot-like hemorrhages. These leaking vessels often lead to swelling or edema in the retina and decreased vision. The next stage is known as proliferative diabetic retinopathy. In this stage, circulation problems cause areas of the retina to become oxygen-deprived or ischemic. New, fragile, vessels develop as the circulatory system attempts to maintain adequate oxygen levels within the retina. This is called neovascularization. Unfortunately, these delicate vessels hemorrhage easily. Blood may leak into the retina and vitreous, causing spots or floaters, along with decreased vision. In the later phases of the disease, continued abnormal vessel growth and scar tissue may cause serious problems such as retinal detachment and glaucoma. 43

Retinal Disorders The retina is a layer of tissue in the back of your eye that senses light and sends images to your brain. In the center of this nerve tissue is the macula. It provides the sharp, central vision needed for reading, driving and seeing fine detail. Retinal disorders affect this vital tissue. They can affect your vision, and some can be serious enough to cause blindness. Examples are • • • •

Retinal detachment - a medical emergency, when the retina is pulled away from the back of the eye Macular pucker - scar tissue on the macula Macular hole - a small break in the macula that usually happens to people over 60 Floaters - cobwebs or specks in your field of vision

Eye Infections Your eyes can get infections from bacteria, fungi or viruses. Eye infections can occur in different parts of the eye and can affect just one eye or both. Two common eye infections are Conjunctivitis - also known as pink eye. Conjunctivitis is often due to an infection. Children frequently get it, and it is very contagious.

Stye - a bump on the eyelid that happens when bacteria from your skin get into the hair follicle of an eyelash. Symptoms of eye infections may include redness, itching, swelling, discharge, pain, or problems with vision. Treatment depends on the cause of the infection and may include compresses, eye drops, creams or antibiotics.

44

Pterygium is a wedge-shaped, raised outgrowth of the conjunctiva. It is a fibrous, vascularized, and opaque tissue that forms at the junction between episclera and the clear cornea. Pterygium is typically seen in the 20-30-year age group and is predominately in males. Living in a tropical climate as well as exposure to ultraviolet light, dust, wind, and noxious chemicals contribute to the spontaneous Pterygium (early) triangular outgrowth. With time, some pterygia will spontaneously become inactive, whereas in other cases the growth affects vision by invading the central cornea. This condition requires surgical excision. Possible Signs and Symptoms • Irritation/Redness • Sensitivity to light • Tearing • Foreign body sensation • Diplopia (double vision) • Increased astigmatism (cylindrical distortion) What can be done to prevent pterygia and invasion of the cornea? Protecting eyes from sun, dust and wind is essential. Artificial tears may be helpful to reduce irritation, and topical steroids may be used to diminish inflammation.

Subconjunctival hemorrhage occurs when a small blood vessel under the conjunctiva breaks and bleeds. It may occur spontaneously or from coughing, heavy lifting, or vomiting. In some cases, it may develop following eye surgery or trauma. Subconjunctival hemorrhage tends to be more common among those with diabetes and hypertension. While it may look frightening, a subconjunctival hemorrhage is essentially harmless. The blood becomes trapped underneath the clear conjunctival tissue, much like a bruise. The blood is visible because it shows through the thin, clear conjunctiva. The blood naturally absorbs within one to three weeks and no treatment is required. Signs and Symptoms • Red, bloody patch on the white of the eye • Painless • No change in vision Treatment Although it may look like an emergency, a subconjunctival hemorrhage does not affect the vision and no treatment is required. 45

Age-related macular degeneration (ARMD) is a degenerative condition of the macula (the central retina). It is the most common cause of vision loss in the United States in those 50 or older, and its prevalence increases with age. AMD is caused by hardening of the arteries that nourish the retina. This deprives the sensitive retinal tissue of oxygen and nutrients that it needs to function and thrive. As a result, the central vision deteriorates. Macular degeneration varies widely in severity. In the worst cases, it causes a complete loss of central vision, making reading or driving impossible. For others, it may only cause slight distortion. Fortunately, macular degeneration does not cause total blindness since it does not affect the peripheral vision.

This example demonstrates what a patient with advanced macular degeneration sees.

What is the difference between wet and dry macular degeneration? AMD is classified as either wet (neovascular) or dry (nonneovascular). About 10% of patients who suffer from macular degeneration have wet AMD. This type occurs when new vessels form to improve the blood supply to oxygen-deprived retinal tissue. However, the new vessels are very delicate and break easily, causing bleeding and damage to surrounding tissue.

What causes macular degeneration? Macular degeneration may be caused by variety of factors. Genetics, age, nutrition, smoking, and sunlight exposure may all play a role. Signs and Symptoms • • •

Loss of central vision. This may be gradual for those with the dry type. Patients with the wet type may experience a sudden decrease of the central vision. Difficulty reading or performing tasks that require the ability to see detail Distorted vision (Straight lines such as a doorway or the edge of a window may appear wavy or bent.)

46

Module 5 – Referrals If patient meets any of the following criteria, then a vision exam is necessary. If the examiner is unable to resolve the problem, or is unsure of the results, a referral to appropriate eye care professional is strongly recommended.

Criteria Recommended Schedule - Patient is due or overdue for a professional eye exam. See Recommended Schedule Guidelines on page 11. History – History or signs of glaucoma, diabetes and hypertension in patient or patient’s family Visual Acuity • Distance – 20/30 or worse in either eye. • Near - 20/40 or worse in either eye or inability to see clearly at a comfortable reading distance. Vision is blurred and patient is under 40. • Child – passed distance vision with 20/30 or lower but strained, squinted, or tilted head, etc. May indicate astigmatism. • Astigmatism – evident. Patient reports some areas of the clock target are blurred and others are clear. Note that astigmatism can be confirmed with the FOCOMETER®. Refractive Error – Patient’s refractive error indicates a need for eyeglasses. Diopter readings were more than plus or minus 0.50 diopters. Color Vision – Patient showed difficulty in recognizing colors Binocular Coordination – Patient’s failed Versions Test and/or Cover/Uncover Test. Eye Condition - Patient’s eyes do not appear as follows and examiner is not trained to treat. • Cornea is clear • Pupil is black • White part (conjunctiva) white • Eyelids open and close properly Other (specify) any complaint or concern, especially regarding pain, expressed by patient or the parent of young patient.

Referral Procedure Referral Sources

Patient Involvement Provide Written Referral

Document Referral

Types - May be a general referral in which the patient chooses the eye care professional or a specific referral chosen by the examiner and/or the examiner’s organization. Barriers - The patient’s lack of financial assets may act as a barrier to either seeing an eye care professional or to obtaining glasses. Prior to making a referral, investigate how this barrier might be overcome. Tell patient the reason for the referral and why it is important to follow-up on the referral. Ask patient if he/she has any concerns or questions. Some organizations may use referral forms. Ideally, the patient should be provided with a name, address and phone number of an eye care professional that is willing to accept the referral on a timely basis. Record on patient’s form and retain in patient’s file: • Referred to • Referred on date • Reason for referral 47

48

Module 6 – Dispensing Eyeglasses Eyeglass Frames Purpose:

Frames hold corrective lenses in their proper place before the eyes.

Types:

1. 2. 3. 4.

Materials:

1. Plastics 2. Metals 3. High Tech

Plastic Metal Combination plastic and metal Rimless

Eyeglass Lenses Purpose:

Correct blurred vision by bending light rays entering the pupil so that the rays converge at the back of the eyeball

Materials:

1. CR-39 2. Polycarbonate or “poly” – safest high impact lenses on the market, require anti-scratch coating because poly is soft

1. Spherical, round like a basketball, two types • Convex – corrects hyperopia or farsightedness • Concave – corrects myopia or nearsightedness Lens Surfaces: 2. Cylindrical, round like a football or an egg, two types • Cylindrical only – corrects astigmatism • Compound, i.e., cylindrical & spherical -- corrects astigmatism and either hyperopia or myopia Prism:

Used to correct faulty eye-muscle imbalances in which eyes do not act as a team. Unless present in strong amounts, prisms will not be conspicuous.

Number of Corrections:

1. Single vision – same focal power throughout the entire lens. 2. Bifocals – upper part has correction for distance vision and lower part has correction for close vision tasks 3. Trifocals – three segments; upper part corrects distance vision; intermediate segment corrects arms-length vision and lower part corrects close work 4. Reading glasses – lower part corrects for close vision and upper part has no correction 49

Customized Glasses vs. Recycled Glasses Access to Effective and Affordable Eyeglasses •

InFOCUS is striving to help others build sustainable eye care systems in which poor, medically underserved communities have access to affordable eye care and eyeglasses on an ongoing basis.

•

Eyeglasses which are customized to correct the refractive errors and other vision problems of individual patients provide the best results for the patients. Several barriers exist to providing poor patients with customized glasses: • Lacks of awareness that affordable customized glasses are available. • Perception that recycled glasses are “free” and “better than no glasses.”

Affordable Glasses Available At present, there are several sources of inexpensive frames and lens that can be ordered from optical supply houses. See “Sources for Inexpensive Eyeglasses” page 59. One supplier offers an inventory of lens for sale that can be secured into frames with a minimum of trimming. This approach enables examiners to provide patients with affordable, customized glasses quickly. Furthermore, the inventory includes lens with correction for astigmatism. Contact InFOCUS Program Manager, Diane Baker, at (281) 398-7525 for more information. People with little income in both developing and developed countries have shown that they are willing to pay for eyeglasses. This willingness, combined with the availability of low cost customized eyeglasses, are the ingredients of a viable market. Low income customers willing to pay for eyeglasses

+

Affordable, customized eyeglasses

=

Sustainable market that benefits suppliers and customers alike

Recycled Glasses Recycled eyeglasses are perceived to be “free” yet money and time is required to collect, store, recondition, measure corrective power of lens, label, and ship the glasses. Ultimately, only a few of the collected glasses will be suitable for dispensing because many glasses are in poor condition or the correction in the lenses makes matching to new owners difficult. Some of the difficulties in matching patients with recycled glasses include: • Each eye often has different correction needs. • A majority of glasses contain corrections for astigmatism. Astigmatic lenses are extremely difficult to match to new wearers because of two variables—axis and strength of the correction. • Lenses often contain corrections for astigmatism and either farsightedness or nearsightedness. • The corrective portion of the lens may not align with the patient’s line of sight. • Prisms in the lens, which are designed to correct faulty eye-muscle imbalances, may cause eyestrain in the new wearer. • Even if lens can be matched to patient’s needs, the frames may be too large or too small or feel uncomfortable. In addition, examiners who dispense recycled glasses should take precautions not to give prescriptions which are too strong for their patients when an exact match in not available. A better solution would be to dispense lens with weaker, rather than stronger, corrective power than needed. 50

Protocol for Dispensing Customized Eyeglasses When to Use

•

Patient’s prescription for corrective lenses has been determined and affordable, customized eyeglasses are available to the patient.

1

Stock and Display Frames

• •

Provide samples of the frames available. Have a mirror available. Stock an eyeglass repair kit.

2

Interview Patient

• • •

Determine the activities of the patient, i.e., sedentary or active. Examine patient’s prescription. Start a Patient’s Record form.

•

3

Locate Best Available Lens and Frames for Patient

Based on patient’s activities, prescription and preferences, help the patient to identify possible matches with the lenses and frames available. Check the fit of frame on patient. Adjust if needed. If comfortable fit cannot be achieved, it is unlikely that patient will wear the glasses.

•

4

Order and • Receive Frames • and Lenses from Optical Supply • House

5

Measure Patient’s Visual Acuity while Wearing Glasses

• • •

•

6

Give eye health and safety information

7

Complete paperwork.

• • •

Place order. Retain copy of order. Receive order. Check eyeglasses against order. Return if eyeglasses do not comply with order. Call patient to return when eyeglasses are ready. Check distance vision and near vision while patient is wearing glasses. If both distance and near vision are clear, then go to step 6. If blurred for either distance or near vision, then record the difficulty on Patient Record form. Determine the source of the problem— prescription or eyeglasses. Return eyeglasses to optical supply house and reorder. Check frames for comfort and fit. Adjust if needed. Provide patient with information on hygiene, nutrition, UV protection, and injury prevention. Provide patient with instructions for wearing and caring for the eyeglasses. Complete Patient Record form re: prescription dispensed and instructions given patient for wearing glasses. Maintain forms in Patient Record files.

51

Recycled Eyeglasses - Criteria for Sorting Discard frame and glasses if…

Keep good frames but discard unsatisfactory lenses…

Keep reading glasses

Keep satisfactory frames and lenses

•

Lenses are scratched and frames are damaged or moldy

Unsatisfactory lenses include • Lenses for astigmatism (images appear wavy through lenses)* • Lenses with a significant difference in correction • Lenses with very strong correction • Lenses with trifocal correction • Lenses with large amount of prism • •

Retain reading only glasses if frames are in good condition Bifocals, which combine a correction for distance on the top and reading on the bottom, should also be retained if prescription can be determined.

• •

Frames and lenses are in good condition. Lenses either have no correction for astigmatism or have astigmatic correction on the horizontal axis (0 to 189 degrees). Lenses with weak to moderate correction

•

Recycled Eyeglasses - Recommended Inventory** • •

Include lenses with low to moderately high amounts of correction For patients with astigmatism, use additional spherical equivalent if correction needed in 2 diopters or less (see “Using Spherical Equivalent to Correct for Astigmatism” on page 57)

Adult and Children’s size frames/lenses

•

Take a variety of sizes and styles

Sunglasses

• •

No prescription Must screen 100% of UV rays

Reading Glasses

•

Stock should include reading only and bifocals with moderate to low correction for distance

Cataract Glasses

•

A few very thick, “Coke bottle” lenses

Safety Goggles

•

No prescription, designed to be placed over glasses

Spherical Correction Only

*Exception: keep glasses with cylinder axis on the horizontal axis (0 to 180 degrees). **When assembling a stock of recycled eyeglasses, contact eye examiners familiar with the area regarding the types of frames and lenses needed by local residents.

52

Protocol for Dispensing Recycled Eyeglasses When to Use - Patient’s prescription for corrective lenses has been determined and affordable, customized eyeglasses are not available to the patient

1.

Sort Recycled Eyeglasses • •

2.

Examine stock of recycled eyeglasses to identify eyeglasses suitable for dispensing. Sort according to “Recycled Glasses- Criteria for Sorting”. Dispose of unsuitable eyeglasses as appropriate. Identify Corrective Power of Lens

• • 3.

On eyeglasses identified as suitable for dispensing, verify the prescription by performing the procedure “Measuring the Corrective Power of Eyeglass Lenses” on page 55. If corrective power of the eyeglasses still meets “suitability criteria”, then add to eyeglasses stock. If not, dispose of eyeglasses as appropriate. Locate Best Available Lens and Frames for Patient

• • • 4.

Examine patient’s prescription* and identify possible matches between patient’s prescription and eyeglasses in stock. For patients with astigmatism, use “spherical equivalent” calculation on page 58 to identify suitable eyeglasses. Check fit of frame on patient. Adjust if possible. If comfortable fit cannot be achieved, it is unlikely that patient will wear glasses. Measure Patient’s Visual Acuity while Wearing Recycled Glasses

• • • • 5.

Check distance vision and near vision using procedures on pages 16 and 17. If both distance and near vision are clear, then go to step 5. If blurred for either distance or near vision, then try other pairs of eyeglasses with corrective powers appropriate for patient. Check frames for comfort and fit. Give eye health and safety information

• • 6.

Provide information on hygiene, nutrition, UV protection, & injury prevention. Provide patient with instructions for wearing and caring for the eyeglasses. Complete paperwork.

•

Complete “Patient Record” form re: prescription dispensed and instructions given to patient for wearing glasses. Maintain forms in patient record files.

**See “How to Read a Prescription” page 62.

53

Protocol for Dispensing Reading Glasses • When to Use

1

Stock and Display Frames

2

Interview Patient

3

Check Distance Vision

•

•

Retain a stock of reading glasses. Include with magnification power rated at +1.00, +1.25, +1.50, +1.75, +2.00, +2.50. • If dispensing recycled glasses, then include in inventory some glasses with correction for reading only and other glasses with two corrections, i.e., for reading and distance vision problems. • • •

Determine the patient’s age. Ask the patient if he/she has other sight difficulties. Start a Patient’s Record Form.

•

Check the patient’s distance vision using Snellen or other standardized chart. Record results. If patient has blurred distance and near vision, then he/she has two options. He/she can use either bifocals or two pairs of eyeglasses: one for distance vision and another for reading. Do not proceed with this procedure. Rather go to the applicable Dispensing Protocol (Customized or Recycled Eyeglasses) in this Module. If patient has clear distance vision and blurred near vision, then go to next step.

• •

• • 4

Select Reading Glasses based on Age

5

Advice Patient on wearing instructions

6

Give eye health and safety information

7

Complete paperwork.

Patient, age 40 or older, experiencing difficulty seeing objects that are near, such as newspaper, or at low illumination. This condition is called Presbyopia. It is caused by a reduction in elasticity of the focusing lens inside the eye.

Try out lenses based on age and adjust as needed. 40 years 45 50 60 65 (and above)

• • • • •

+1.00 +1.25 +1.50 +2.00 +2.50 (or as needed)

Tell patient that reading glasses are designed for close reading and work. The magnification portion of the reading glasses should not be used to see distant objects. Provide patient with information on hygiene, nutrition, UV protection, and injury prevention. Provide patient with instructions for wearing and caring for the eyeglasses. Complete Patient Record form re: prescription dispensed and instructions given to patient for wearing glasses. Maintain forms in Patient Record files. 54

Procedure: Using FOCOMETER® to Neutralize the Corrective Power of Lenses Purpose:

Illumination: Target: Distance: Lenses: Equipment: Instructions to Patient: Steps:

To verify the actual corrective power of spectacles. This procedure is called lensometry Note: Persons with astigmatism should not perform this procedure because the calculations involved are very cumbersome. Moderate Clock Target 20’ or 6 meters from examiner to target Corrective lenses that are being neutralized. Corrective lenses of the examiner if applicable FOCOMETER® Not applicable

Examine Glasses – Identify and discard glasses with correction for astigmatism. Exception: Retain glasses with astigmatic correction on the horizontal axis because this is the most common type of astigmatic correction needed. Look through each lens while rotating it about center of the lens and look for distortion. Corrective lenses without stigmatic correction will show a constant blur but no distortion. Examiner’s Prescription – Measure and record the refractive error, if any, of the person who is performing this procedure. See procedure “Using FOCOMETER® for Refractive Error” in Module 2. Examiner Wears Glasses – Lenses are worn in the following manner. • If the person performing the procedure has zero refractive errors, then he/she puts on the glasses being measured • If person has other than zero refractive error, then the person puts on his/her own lenses and then places the lenses to be measured on top. Test Right Eye First – FOCOMETER® is adjusted to full plus position, i.e., fully extended. The examiner views the clock target through the FOCOMETER® using right eye, left eye covered, and rotates the collar to the right. Readings on FOCOMETER® will be progressively negative. As soon as target is clear, the person stops turning the collar and notes the FOCOMETER® reading. •

If person doing the procedure has zero refractive error, then the number obtained is the power in diopters of the eyeglass prescription. However, the sign (plus or minus) of the eyeglass prescription is the opposite of the sign obtained with the FOCOMETER®. FOCOMETER® READING = Ex. Ex.

CORRECTIVE POWER of LENS (Opposite of FOCOMETER® Reading) -3.50 +1.75

+3.50 –1.75

55

•

.

If the person doing the procedure has other than zero refractive error, then his/her refractive error must be subtracted from the FOCOMETER® reading to calculate the power of the eye glasses. FOCOMETER® READING 0

Minus EXAMINER’S PRESCRIPTION -- 1.00

Equals CORRECTIVE POWER of LENS -- 1.00

.

–3.00

-- 1.00

-- 2.00

.

+2.50

-- 1.75

.75

Test Left Eye Second - Repeat step 4 using left eye and covering right eye. Test Right Eye Again - Repeat step 4 using right eye again. If results are different, repeat again. Label glasses with corrective power of each lens if glasses are to be recycled. Notes:

In situations where new glasses are difficult to obtain and the individual has up to two diopters of cylinder, then lenses with no correction for astigmatism (spherical lenses) can be used. See “Using Spherical Equivalent to Correct for Astigmatism” on the next page. Only spherical lenses should be dispensed in a program using only recycled glasses. Exception: lenses with astigmatic correction on the horizontal axis should be included in inventories of recycled glasses as this is the most common type of astigmatic correction needed.

56

Procedure: Using Spherical Equivalent to Correct for Astigmatism

Purpose:

To correct for astigmatism by using additional spherical power instead of cylinder. This procedure is used when lenses with astigmatic correction are not available and patient’s cylinder in his/her prescription is no more than two diopters. Over 90% of patients will have a major improvement in visual acuity when spherical power is increased using spherical equivalent

Formula:

Spherical measurement + half of the cylinder measurement = spherical equivalent

Steps:

1. Identify patient’s astigmatic error. If not already known, measure astigmatic error using the FOCOMETER® as described in Module 2 – Using FOCOMETER® for Astigmatic Error. 2. Right Eye First – Review patient’s data on radials. •

First radial (called SPHERE) – Ex. -2.00 diopters at AXIS of 30 degrees

•

Second, Perpendicular radial – Ex. -3.50 at AXIS of 120 degrees (always 900 from first radial)

3. Calculate CYLINDER by finding the difference in diopters between the two radials •

Ex. ((-3.50) – (-2.00)) = ((-3.50) + 2.00) = -1.50 diopters

4. Prescription for this eye then requires the following lens: •

Ex. SPHERE –2.00 CYLINDER –1.50 diopters AXIS 120 degrees

5. Calculate SPHERICAL EQUIVALENT Spherical measurement + half of the cylinder measurement •

Ex. -2.00 + -.75 = -2.75 diopters

Correct notation is: • Ex. R: -2.75 S 6. Left Eye – Repeat steps 2 - 5. See another example on next page.

57

Using Spherical Equivalent to Correct for Astigmatism Example: Clock Target Calculating Cylinder

• • •

First radial (spherical correction). Second radial perpendicular to first radial. CYLINDER calculated by subtracting FOCOMETER® reading at second radial minus FOCOMETER® reading at first radial.

Diopters

+1.00

- 1.00

Axis

120 degrees

30 degrees

-1.00 – (+1.00)= -1.00 - +1.00= -2.00 30 degrees

Prescription (Rx) written as follows: Sphere (SPH)

Cylinder (CYL)

Axis

+1.00

-2.00*

30 degrees

Spherical Equivalent for same prescription recorded as: +2.00S. Calculation follows: Sphere (SPH) +1.00

plus ½ of Cylinder

equals Spherical Equivalent

-1.00

0.00 plano

*Patients with cylinder of up to 2.00 diopters can be helped using spherical equivalent

1st radial (sphere) 2nd radial

Difference between 2nd radial minus 1st radial = Cylinder

58

Sources of Inexpensive Eyeglasses New Eyeglasses InFOCUS can offer Eye Deal Eyewear’s Instant Eyeglasses™ at special low prices. Instant Eyeglasses™ are a unique design that allows assembly of frames and lenses so that individual’s prescription can be dispensed in only a few minutes following the eye exam. These eyeglasses are optically accurate and correct for myopia, hyperopia, presbyopia, and astigmatic conditions. Lenses are single vision, including correction for astigmatism. Instant Eyeglasses™ are ideal to use in rural and remote areas with little or no access to an optical lab, or when patients are seen on a one-time basis. Frame styles are designed to accommodate a broad range of interpupillary distances. Pre-molded round lenses fit into frames that come in sizes to fit almost any face. The sizes available are large (46mm) and small (42mm) in gold metal frames. For more information contact Eye Deal Eyewear, Inc. 2620 Manatee Ave W., Ste A Bradenton, FL 34205-4944; Phone 866-221-6790.

Example of Instant Eyeglass™ available from InFOCUS

Recycled (used) Glasses The SBC Pioneers Eyeglass Bank, 1714 Ashland Avenue, Room 23, Houston, Texas 77008; Contact: Wanda Schoellkopf; Ph: 713 865 5713 Lions Clubs Eyeglass Recycling Centers, Visit www.lionsclubs.org to locate a recycling center near you or contact Multi-district Coordinator Denisa Marston, at Texas Lions Eyeglass Recycling Center, Midland, Texas Ph: 915 683 3611; Email: [email protected]

59

Procedure for orienting cylinder axis when assembling Instant Eyeglasses™ Remove demo lenses, if installed, from the frames to be used 1. Place right eyewire of the frame on the clock target below 2. Be sure that the frame bridge and other eyewire is placed parallel to the 3-9 o’clock or 180 degree axis, or parallel to the bottom of the page 3. Mark the prescription axis on the frame rim with a dot or line 4. Align the lens axis mark with the frame mark 5. Install the right eye prescription in the right lens frame 6. Repeat procedure for the left lens frame front

hinges

nose pad

temples

Bridge Front of frame

60

eyewire

Procedure: Measuring Pupillary Distance (PD) Purpose:

To determine the distance between the pupils when fixated on a distance object (Distance PD) and on a near object (Near PD). When eyeglasses match the PD of the patient, the patient sees through the optical center of the lenses without straining.

Illumination:

Moderate

Target:

Penlight

Distance:

14”

Lenses:

None

Other materials:

Millimeter ruler, pen, and patient record

Instructions:

Tell patient to fixate at the penlight with both eyes open and to stay still.

To measure Near Pupillary Distance (P.D.) 1. Examiner holds penlight close to his/her left eye 14” in front of the patient. Examiner closes his/her right eye. 2. Examiner tells patient to look at the penlight with both eyes open. 3. Examiner holds a centimeter ruler in front of the patient and aligns the zero on the ruler with the outer edge of the patient’s right iris. 4. Examiner finds the Near P.D. by noting the distance between • the outer edge of the patient’s right iris and • the inner edge of the patient’s left iris. See diagram below. 5. Record the Near P.D. Examiner and Patient: Be careful not to move ruler or head between measuring Near P.D. and Distance P.D. To measure Distance Pupillary Distance (P.D.) 1. Examiner moves penlight to just below his/her right eye. Examiner closes his/her left eye. 2. Examiner tells patient to keep looking at the penlight with both eyes open. 3. Examiner finds the Distance P.D. by noting the distance between • the outer edge of the patient’s right iris where the ‘zero’ on the ruler is placed as shown in the diagram below. • the inner edge of the patient’s left iris. This is the ‘Distance P.D.’ Without moving the ruler now the patient is asked to look at the penlight just below the examiner left eye. 4. Examiner records the Distance P.D. (Same two points as in step 3) Notes: Record:

P.D. is usually within a range of 55 to 75 centimeters. Near P.D. is always less than Distance P.D. and the difference is typically approximately 3 centimeters. Near P.D.

Distance P.D.

61

How to Read a Prescription Layout of a Prescription (Rx) Example: R.E. L.E.

Sph -3.25 -2.00

Cyl --0.50

Axis -165

Prism 1.5 IN 1.5 IN

Add + 1.75 + 1.75

Near PD Dist. PD Seg Ht.

61 64 19

Most prescriptions are set up in a specific layout as seen above. The prescription (aka “Rx”) includes the right and left sphere, cylinder, axis, prism, and add readings.

Interpreting Prescription Abbreviations R.E.

Right eye

L.E.

Left eye

Sph

Spherical power, corrects for either hypermetropia/farsightedness (plus sign) or myopia/nearsightedness (minus sign)

Cyl

Cylinder power, corrects for astigmatism

Axis

Axis of lens rotation, applicable to cylinder power

Prism

Corrects distance vision displacement

Add

Power of correction to be added to sphere needed for reading

PD

Pupillary distance, distance between the pupils in centimeters during distance vision

Near PD

Pupillary distance during reading vision

Segment Height

Position of the “add”, or bifocal, included for near vision

Transposition Some doctors write their prescriptions in plus cylinder, some in minus cylinder. There is a standard formula to convert from one to the other. This formula is called transposition. There are three basic steps.

Steps

Example of Transposition (Plus to Minus)

1. Algebraically add the sphere to the cylinder. This becomes your new sphere value. 2. Change the sign on the cylinder, keeping the numeric value the same. 3. Add or subtract 90 to the axis, keeping it between 1 and 180. Prescription in plus cylinder is: -2.50 S +1.00 C 140 axis 1. –2.50 added to +1.00 = new sphere value of –1.50 2. Change sign of the +1.00 cyl = new cyl value of –1.00 3. Add or subtract 90 to the axis of 140 = new axis value of 50 Same prescription in minus cylinder is: -1.50 S -1.00 C 50 axis 62

Module 7 – Record Keeping Maintaining Clinical and Fiscal Records Record keeping is key to: • •

Providing good service to patients Monitoring the use and cost/benefit of services and products provided

Clinical Records • • • • •

Use a Patient Record form designed to capture information about the patient’s history, vision check, health check, etc. Require that Patient Record form be used with every patient and signed by the person performing the exam. Require that the Patient Record form is filed in an accessible and secure place and that either a person or position is designated to maintain the files. Periodically, check to ensure that Patient Record forms are being completed and retained for each patient. At least once a year, compile statistics from the Patient Record forms to determine patterns and to identify possible areas of improvement.

Referral Forms • •

When referring the patient to a specific provider, provide them with a written referral form on which the provider’s name, location, and phone number is listed. Record referral information on Patient’s Record.

Inventory Forms • •

Document orders placed and shipments received for frames and lenses Review periodically to identify trends and areas for improvement

Fiscal Records • • • •

Identify the costs and revenues associated with the eye-related activities. Identify how each cost and revenue will be tracked. Document in writing. Implement tracking system and create monthly reports of cost vs. revenue. At least once a year, review tracking system to identify areas for improvement.

63

64

Appendix Glossary Add - The add power is the amount of correction to be added to the sphere for a reading or near power. The add power assists the weakened eye muscles to view closer objects. It is usually a value between +1.00 and +3.00. We commonly use a bifocal for this. A bifocal is a lens that has the distance correction in the normal viewing area and a smaller segment for reading lower in the lens. We commonly use a Flat top 28 (FT – 28). A FT –28 is a half circle segment add with a 28mm diameter Astigmatism – a condition caused by an irregularity in the shape of the cornea which prevents light from focusing correctly on the retina thereby causing blurred vision. Symptoms may include headaches, fatigue, eye strain, or blurred vision at certain or all distances. Axis – the location of the cylinder component in the compound lens. Written as a degree of rotation from 0-180 degrees. Bifocal - a lens that is designed with two different prescription areas to correct for both near and distance vision. Bridge - the part of a spectacle frame that extends across the nose. Compound lens – a lens which combines both spherical and cylinder lenses. Cylinder - The amount of correction needed beyond the sphere to correct for astigmatism. This could be written in two forms, either plus or minus cylinder. It is identified by a “+” or “-“ in front of the value. There is a formula that allows you to convert from plus to minus or minus to plus. It is called transposition. See below for the formula. Minus cylinder is most commonly used and is the conversion preferred by optometrists. Plus cylinder is often used by ophthalmologists. Cylinder lens – a lens with a surface shaped like a rod (cylinder). Used in combination with spherical lenses for patients with astigmatism and spherical error. Diopter (D) - Unit to designate the refractive power of a lens. Hyperopia - farsightedness; vision of nearby objects is impaired, while distance objects remain in relative focus. Light is focused on a point that lies behind the retina. Iris - Pigmented tissue lying behind the cornea that gives color to the eye (e.g., blue eyes) and controls amount of light entering the eye by varying the size of the pupillary opening. Lens - transparent structure within the eye that focuses light rays upon the retina.

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Myopia - nearsightedness; close objects are in relative focus while distant objects are blurred. Light is focused on a point that lies in front of the retina. Ophthalmologist - a doctor of medicine (M.D.) or doctor of osteopathy (D.O.) who specializes in both the medical treatment and surgical care of the eyes and the visual system. Ophthalmologists must complete four or more years of medical school, one year of internship, and three or more years of specialized training and experience. Optician - state licensed professionals who interpret and fill a prescription from an optometrist or ophthalmologist for corrective eyewear. An optician is trained in the selection and fitting of eyeglasses and contacts (with special license). Qualifications for licensure include successful completion of a 2 year college program in optical science or a 2 year apprenticeship under a licensed optician or optometrist, followed by a state license examination. Opticians must also attend continuing education classes each year to maintain their license. Optometrist - doctors of optometry (O.D.) who specialize in the examination of the eyes and the visual system as well as the diagnosis and treatment of certain ocular diseases, injuries, and other health problems. An optometrist can prescribe many ophthalmic medications, but cannot perform surgery. They may, however, participate in pre-operative and post-operative care relating to eye surgery. Optometrists must complete four years of post-graduate optometry school. PD - The PD is the distance between the pupils in centimeters. Near PD is measured when the eyes are fixated on a close object. Because the eyes must turn in to view nearby objects, Near PD is always smaller than Distance PD. The normal difference between Near PD and Distance PD is approximately 3 centimeters. See Appendix for procedure on how to measure PD. Plus and minus notation for lenses that correct astigmatism - compound lenses are manufactured by combining a spherical lens with a cylinder lens. The cylindrical compound lens may be considered either a negative or positive diopter lens. The convention that is used must be indicated by a plus (+) or negative (-) sign before the power of cylinder correction. Prism – a wedge shaped component of an optical lens is used in prescription glasses for correcting near vision and or for correcting a patient with strabismus. Presbyopia – an inability to see items clearly at reading distance. The natural lens in the eye is unable to focus due to structural changes as a result of aging. Pupil - the adjustable opening at the center of the iris that allows variable amounts of light into the eye. The pupil will expand or dilate in response to low light conditions in an attempt to bring more light into the eye and will reduce in size when intense light is present. Refraction - test to determine an eye's refractive error and the best corrective lenses to be prescribed. Series of lenses in graded powers are presented to determine which provide sharpest, clearest vision. 66

Refractive error - optical defect in an unaccommodating eye; parallel light rays are not brought to a sharp focus precisely on the retina, producing a blurred retinal image. Can be corrected by eyeglasses, contact lenses, or refractive surgery. Retina - a thin layer of light sensitive nerve tissue lining the interior of the eye that translates light waves into nerve impulses that are sent to the brain. Retinal detachment - occurs when the retina separates from the rear wall of the eye. Vision loss occurs at these detached areas. Sclera - the outer layer of the eye that forms the visible white area of the eye and extends from the cornea in the front of the eye to the back of the eye where it meets and surrounds the optic nerve. Sphere - The amount of correction needed to correct for near (myopia) or far sightedness (hypermetropia). There is no limit to what the correction could be. The normal range is +6.00 to –6.00. Spherical lens – either concave (minus or negative power) or convex (plus or positive power) in shape used to correct visual refractive errors. Concave lenses correct myopia (nearsightedness) by causing light to diverge. Convex lenses correct hyperopia (farsightedness) by causing light to converge. 20/20 - Normal visual acuity. Upper number is the standard distance (20 feet) between an eye being tested and the eye chart; lower number indicates that a tested eye can see the same small standard-sized letters or symbols as a normal eye at 20 feet. Visual acuity – how clearly a person can see either at distance or near. Visual acuity measurements are assessed with visual targets at standard distances of 20 feet or 6 meters at distance and 14 inches at near.

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Eye Care Links The following resources will help you make informed decisions, but they are not a substitute for medical care. Discuss information provided in these links with your health care provider. If you are experiencing problems with your vision or eyes, visit an eye care professional immediately. I. How Vision Systems Work 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21.

American College of Chiropractic Rehabilitation Science ..................www.accrs.org Anchorage Health Online .................................................www.anchoragehealth.org American Psychological Association.................................................... www.apa.org CenterWatch Clinical Trials Listing Service............................www.centerwatch.com University of Texas Dept of Computer Sciences ........................ www.cs.utexas.edu Jacob L. Driesen. Ph.D. Neuropsychology & Medical Resources . www.driesen.com Galaxy Search Engine.....................................................................www.galaxy.com How Stuff Works ................................................................ www.howstuffworks.com The Hybrid Vigor Institute.......................................................... www.hybridvigor.net International Society of Refractive Surgery ...........................................www.isrs.org The Vision Correction Website.....................................................www.lasersite.com Worldwide Directory of Eye Care [email protected] Macular Degeneration Support ................................................. www.mdsupport.org New York Online Access to Health ......................................... www.noah-health.org Sola Eyeglass Lenses for the Way you Live ...................................... www.sola.com St. Luke’s Cataract & Laser Institute ........................................ www.stlukeseye.com University of Rochester Medical Center ................................ www.stronghealth.com SUNY State College of Optometry ................................................ www.sunyopt.edu Think Quest...............................................................................www.thinkquest.com Vision Channel ......................................................................www.visionchannel.net York University .................................................................................... www.yorku.ca

II. General Eye Care 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17.

Meredith W. Morgan University Eye Center .............................. www.caleyecare.org Caring for Kids ..................................................................www.caringforkids.cps.ca Centers for Disease Control and Prevention ........................................ www.cdc.gov Center Watch Clinical Trails Listing Service...........................www.centerwatch.com Eye Care Office of Ofner & Fleming................................. www.eugeneeyecare.com NJSOP Society of Optometric Physicians......................................www.eyecare.org Eye care India .......................................................................www.eyecareindia.com EyeMDLink..............................................................................www.eyemedlink.com The Stanford Health Library ..................................... www.healthlibrary.stanford.edu Health on the Net Foundation ................................................................www.hon.ch The Eye Site A Real Site for Sore Eyes .............................................www.i-care.net Laser Eye Surgery Doc Shop............................ www.lasereyesurgerydocshop.com Physician-Patient Communications Network................................. www.medem.com Methodist Health Care System.........................................www.methodisthealth.com My Healthy Eyes ............................................................... www.myhealthyeyes.com National Eye Institute ...................................................................... www.nei.nih.gov Internet Ophthalmology.....................................................................www.opthal.org 69

18. 19. 20. 21. 22. 23. 24.

Optometrists Association Australia ....................................www.optometrists.asn.au ORBIS Saving Sight Worldwide .....................................................www.orbis.org-hk Royal National Institute of the Blind .................................................www.mib-org.uk St. Luke’s Cataract & Laser Institute....................................... www.stlukes-eye.com Sports Vision Institute .......................................................... www.vision4sports.com The Cornea and Laser Eye Institute .................................. www.vision-institute.com Vision Therapy ....................................................................www.vision-therapy.com

III. Common Vision Problems 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32.

Adult Strabismus................................................................www.adultstrabismus.org Alan Optics ............................................................................www.alanoptics.per.sg All About Vision................................................................... www.allaboutvision.com Bausch & Lomb..............................................................................www.bausch.com Canadian Pediatric Society............................................... www.caringforkids.cps.ca Cascade Eye Center................................................................ www.cascadeye.com The Low Vision Centers of Indiana .................................... www.eyeassociates.com EyeMAC Development, LLC .........................................................www.eyemac.com Eyesite Canadian Ophthalmological Society ....................................www.eyesite.ca American Academy of Family Physicians ............................... www.familydoctor.org Discovery Health Channel .............................................. www.health.discovery.com Eye & Vision Care Health Ctr..... www.health.yahoo.com/health/centers/eye_vision/ Health On the Net Foundation ............................................................... www.hon.ch University of Michigan Kellogg Eye Center .......................... www.kellogg.umich.edu Very Best Kids! .......................www.wywy.essortment.com/kidsinformatio_rsdh.htm Mayo Clinic .............................................................................. www.mayoclinic.com American Academy of Ophthalmology.......................................... www.medem.com Methodist Health Care System ........................................www.methodisthealth.com Myopia Manual by Dr. Klaus Schmid .................................. www.myopia-manual.de British Columbia Association of Optometrists ......................www.optometrists.bc.ca Patanol.......................................................................................... www.patanol.com Parents Active for Vision Education ........................................... www.pave-eye.com Prevent Blindness America..............................................www.preventblindness.org Sola International ................................................................................www.sola.com St. Luke’s Cataract & Laser Institute....................................... www.stlukes-eye.com The Med Guide – Eye Care .................................... www.themeguide.com/docs/eye University Health Services .....................................................www.uhs.berkeley.edu Colorado Optometric Association................................................www.visioncare.org The Vision Help Network .......................................................... www.visionhelp.com Vision Therapy ....................................................................www.vision-therapy.com Vision World Wide........................................................................ www.visionww.org Vision, Reading and Computer Users.........................................www.webword.com

IV. Refractive Surgery 1. 2. 3. 4. 5.

Laser Eye Center of Silicon Valley.........................................www.2020eyesite.com Alcon.......................................................................................... www.alconlabs.com All About Vision................................................................... www.allaboutvision.com American Society of Cataract & Refractive Surgery........................... www.ascrs.org Ask Lasik Doctors .................................................................www.asklasikdocs.com 70

6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22.

The Harman Eye Clinic ...................................................www.cascaderegional.com The Cleveland Clinic ........................................................... www.clevelandclinic.org Clinica Reinoso ................................................................... www.clinicareinoso.com Hayden & Kovach Eye Center................................. www.eyelaser-chicagoland.com Eye Search The Ultimate Eye & vision Portal .......................... www.eyesearch.com International Society of Refractive Surgery ...........................................www.isrs.org The Vision Correction Website.................................................... www.lasersite.com Laser Surgery for Eyes.............................................. www.lasersurgeryforeyes.com LASIK Institute ........................................................................www.lasikinstitute.org U.S. National Library of Medicine................................................... www.nlm.nih.gov Pacific Cataract and Laser Institute..................................................... www.pcli.com Park and Lasik Today ..........................................................................www.prk.com Refractec..................................................................................... www.refractec.com Refractive Source............................................................ www.refractivesource.com Review of Refractive Surgery............................ www.reviewofrefractivesurgery.com Slack Inc. Healthcare Specialty.................................................... www.slackinc.com Council for Refractive Surgery Quality Assurance ........................ www.usaeyes.org

V. Eyewear 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29.

All About Vision ................................................................... www.allaboutvision.com Andersen Eye Associates .................................................... www.anderseneye.com Bausch & Lomb ............................................................................. www.bausch.com CIBA Vision ............................................................................... www.cibavision.com Contact Lens Manufacturers Association............................................ www.clma.net UK Internet Shopping......................................................www.come-shopping.co.uk Contact Lens Council .................................................... www.contactlenscouncil.org Guide from Contact Lens Manufacturers Association .......... www.contactlenses.org University of Tennessee Dept of Ophthalmology ..................... www.eye.utmem.edu Eyewear Concepts ........................................................ www.eyewearconcepts.com Paul Adler Optometrist UK ........................................................ www.eyezone.co.uk Frames Direct........................................................................ www.framesdirect.com InFOCUS Interprofessional Fostering of Ophthalmic Care for Underserved Sectors .............................................................................................. www.infocusonline.org Knighton Optical................................................................ www.knightonoptical.com LensCrafters........................................................................... www.lenscrafters.com Lens Express .........................................................................www.lensexpress.com My Eye Net................................................................................ www.myeyenet.com Novelty Contact Lenses ........................................ www.novelty-contact-lenses.com Optima.................................................................................. www.optima-hyper.com Outpost Optical ...................................................................www.outpostoptical.com Renton Vision Source ............................................................www.rentonvision.com Prescription Dive Mask............................................................www.rxdivemask.com The Eye Center .....................................................................www.sandiegoeye.com Virginia Beach Eye Surgery ............................................................ www.vbeye.com Vision 1 to 1 ..............................................................................www.vision1to1.com Vision Colored Contact Lenses ...................... www.visioncoloredcontactlenses.com Vision RX ......................................................................................www.visionrx.com Vision Web ................................................................................ www.visionweb.com WPS Optometrists UK................................................... www.wpsoptometrists.co.uk 71

30. Contact Lenses and Lens Wear Information Portal....................www.wwwcops.com VI. Eye Diseases 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45.

American Academy of Ophthalmology..................................................www.aao.org American Health Assistance Foundation ............................................www.ahaf.org All About Vision................................................................... www.allaboutvision.com American Optometric Association ....................................................www.aoanet.org The American Society of Cataract & Refractive Surgery ................... www.ascrs.org American Society of Ophthalmic Plastic & Reconstructive Surgery. www.asoprs.org Home Foundation Fighting Blindness ......................................... www.blindness.org The Harman Eye Clinic ................................................... www.cascaderegional.com Dr. Angela Howell, Optometrist......................................... www.drangelahowell.com eMedicine Clinical Knowledge Base .........................................www.emedicine.com Eye Atlas of Ophthalmology.........................................................www.eyeatlas.com Eye Cancer Network .................................................................www.eyecancer.com Eye Disease Online: Your Eye Disease Information Center .. www.eye-disease.com Eye MD Link.............................................................................. www.eyemdlink.com Glaucoma Research Foundation ................................................ www.glaucoma.org Glaucoma Foundation............................................... www.glaucomafoundation.com Health Library at Stanford ........................................ www.healthlibrary.stanford.edu Center for Keratoconus...................................................................www.kcenter.org Lighthouse International............................................................. www.lighthouse.org The Low Vision Gateway ............................................................. www.lowvision.org Understanding & Coping with Macular Diseases ............................ www.macula.org American Macular Degeneration Foundation............................... www.macular.com Macular Degeneration Network................................www.macular-degeneration.org Macular Degeneration Support ..................................................www.mdsupport.org Medem Inc. ................................................................................... www.medem.com Free Medical Dictionary ..........................................................www.medfriendly.com The Merck Manual of Medical Information ...................................... www.merck.com Karolinska Institute.......................................http://www.mic.ki.se/Diseases/c11.html My Eye World......................................................................... www.myeyeworld.com National Association for Visually Handicapped...................................www.navh.org New England Eye Center.................................................................. www.neec.com National Eye Institute ...................................................................... www.nei.nih.gov New York Institute for Special Education ........................................... www.nyise.org Prevent Blindness America..............................................www.preventblindness.org Red Atlas – Recognizing Eye Disease......................................... www.redatlas.com All About Retinitis-Pigmentosa................................... www.retinitis-pigmentosa.com American College of Rheumatology...................................... www.rheumatology.org International Surgical Eye Expeditions............................................. www.seeintl.org St Luke’s Cataract & Laser Institute......................................... www.stlukeseye.com Retina Information Source ................................................www.theretinasource.com Helen Keller International Trachoma Program........................ www.trachomahki.org Vision Channel...................................................................... www.visionchannel.net Vision Works, Inc. .............................................................www.visionworksusa.com Vitreous-Retina-Macula Consultants............................................... www.vrmny.com Washington Academy of Eye Physicians & Surgeons ............... www.wa-eyemd.org 72

Equipment/Materials List for Primary Eye Care Activity

Equipment & Materials

Record Keeping

• • • •

Patient Record forms Referral forms Inventory –order forms, packing lists Fiscal – invoices, bills issued

Measuring Distance Vision

• • • • •

Standard eye chart – Snellen*, Tumbling ‘E’*, Lamboldt C are most common Tape, nails or other means to hang chart String 20 feet (or 6 meters long) or other measuring device Opaque Occluder to cover eye Cut out of letter ‘E’ for use with Tumbling ‘E’ chart

Measuring Near Vision

• •

Near Point Card*–or-usual reading material for patient Simple puzzle or puppet for children

Pinhole Occluder

•

Pinhole Occluder

Binocular Dysfunction Color Blindness

•

Same charts as used for measuring distance vision

•

Color Vision Plates

Measuring Refractive Error

• • • •

FOCOMETER® * Tripod for FOCOMETER® (optional) Clock Target chart* String 20’ long or other measuring device

Promoting Eye Health & Safety

• • •

Table top flipchart – “Eye Health for Everyone”* Booklet—“I Can See”* for children Tabletop flipchart – “Onchocerciasis River Blindness”*

Treating Injuries & Disease

•

Eye patches made of: • sterile gauze or very clean cloth to cushion the eye • a stiff cone made of material such as X-ray film, heavy paper or cardboard. Also, scissors to cut the material • tape

*Items “Available from InFOCUS” see our website www.infocusonline.org

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Equipment/Materials List for Primary Eye Care Activity

Treating Injuries & Disease

Dispensing Eyeglasses

Handling Money

Equipment & Materials • • • • • • • • •

Everting lid – match, clean cotton swab or clean cloth Eye dropper Compress Antibiotic eye ointment 1% Tetracycline ointment Bandages Vitamin A capsules Aspirin and equivalents Clean sterile water or means to sterilize water

• • • • • • • • •

Customized Eyeglasses Samples and displays of frames Order form for glasses and frames Recycled Eyeglasses Inventory of suitable eyeglasses, sunglasses and safety goggles Labels to affix to glasses re: prescription Mirror Drawer or box to store eyeglasses Eyeglass holders to be dispensed with glasses

•

Money box with combination lock

Other items

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Interprofessional Fostering of Ophthalmic Care for Underserved Sectors

a non-profit organization promoting “eye care for all"

19728 Saums Rd., PMB #136 Houston, Texas 77084 Ph: (281) 398-7525 Fax: (281) 398-7428 Email: [email protected] Website: www.infocusonline.org