Dr Kakaza Lectures and Ward Round Notes_0220
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THE NEUROLOGICAL EXAM:
1) get proper history (acute vs slow onset; acute always imply vascular, slow can be mass lesion, demyelination)
2) Do cognitive score, but remember it says nothing about insight and judgement. Ask if someone is forgetful, can they still calculate, do they struggle to read, do they get lost? 3) Ask separately about all the cranial nerves 4) Ask about mood and sleep 5) Ask about power Myasthenia gets worse with exertion – (fatigability) Lower limb: can you get up out of chair? Walk up the stairs? Upper limb: can you brush your hair and your teeth? Open taps or bottles? Do you drop things? On examination the most important thing with motor is to decide UMN or LMN (with UMN no wasting, brisk reflexes, Babinski en Hoffmans, spasticity, no fasciculation, muscles affected in groups, ie flexor group)
6) Ask about sensation: increased or loss of sensation? Increase in sensation includes paresthesias, hyperesthesia, hyperalgesia (Increased or heightened sensitivity to pain) and allodynia (feeling of pain with non-painful stimuli). Only places where dermatomes are of importance are with radiculopathy and myelopathy If sensory doesn’t fit, discard – too subjective
7) Ask about neuro problems with intermittent signs such as headache, epilepsy, TIA, MS, episodic ataxia, episodic paralysis. 8) Ask about autonomic problems such as bowel and bladder – incontinence, frequency, urgency, nocturia Ask about cerebellar – are you ever clumsy, dizzy, suffer from vertigo? VANISH DDT Vertigo (hallucination of movement) Ataxia: broad based gait, reeling, heel-toe walk (tandem) clumsy Nystagmus: horizontal nystagmus, and gaze evoked – will not see in primary position; pt may also have ‘broken saccades’ (non-smooth eyemovements), saccadic intrusion Intention tremor (draw circle on hand, pick up a pen) Speech: staccato and monotone, may have bursts of irregular speech (cerebellar dysarthria) Hypotonia and rebound: push down arms – will jerk up, oscillation, (hypotonia and reflexes with lag) Dysdiadokineses: remember patient must not brace arm – elbow must be away from body Dysmetria: toe to finger, nose to finger will have past-pointing, also ocular dysmetria – eyes overshoot when looking at something (remember to lift shoulders and elbows – pt must not brace his arm)
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Titubation: (vermis pathology) Before you comment on cerebellar signs, think about weakness, spasticity or rigidity – it can all look like cerebellar problems Causes of cerebellar problems: alcohol, drugs, infections such as VZV (gives diffuse inflammation, called cerebellitis), space occupying lesions (hemi-ataxia), paraneoplastic syndromes, stroke in posterior circulation, MS. spino-cerebellar ataxia Cerebellum and CN VIII very sensitive to hypoxic or toxic damage – perinatal hypoxia and childhood infections with meningo-encephalitis often give deafness and cerebellar signs as sequelae Friedrich’s ataxia gives a combination of posterior column fallout due to cord atrophy and well as cerebellar signs due to cerebellar atrophy. GAIT: Aided or not? Look at feet, are they wide-based or not? Do they lift or drag? Arm movement Are the knees bent or straight? Straight line? How does he turn? Waddle – weak girdle muscles – myopathy Scissor (spasticity) UMN Toe walking (S1), on heels (L5) When you present: 1. Cognition – do cognitive score
2. Cranial nerves: if not involved at all the problem is not in the brain. II, V, VII does not have bilateral supply – look especially for defects with them if you have a stroke patient. If checkerboard means brainstem – look especially for logical defects in CN (III alone, VI with VII, IX with X)
3. Motor system: this is combination of power, tone and reflexes, present them as one. a) Start with power in UL and LL, say what patient is able to do: the patient is not able to sit up, to walk; don’t mention power individually – say the power in the UL is overall 2/5 and the LL 3/5 (arm more affected – MCA), or the UL is overall 3/5 and the LL is 1/5 (leg more affected – ACA). Mention whether the power is equal proximally and distally, or worse distally (neuropathy) or worse proximally
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(myopathy) – look for Beevor sign in non-ambulant patient – pt must try to sit up in bed, if the umbilicus goes up the lesion is at T10 – if no Beevor sign the lesion must be above T8) Quick check for power: UL proximal, lift arms above head, distal grip fingers; LL proximal squat, distal walk on heels and toes b) Tone: UL and LL: Low tone usually implies LMN, or UMN in the acute phase before spasticity sets in; with low tone due to LMN you’ll get long history, not acute, recent onset. Increased tone is either spasticity, or rigidity, or paratonia Spasticity implies UMN lesion – a cortico-spinal problem where you get claspknife phenomena with a catch and release sign. This is velocity dependant – won’t elicit it is you move too slowly. Start slowly and increase your speed. It will be more noticeable in the flexors of the UL and extensors of the lower limbs (this is nature’s way of keeping you upright when tone has to compensate for weakness, the arm is flexed and adducted close to body, and the leg is extended with knee locked to be able to stand – increase tone can keep someone walking – don’t decrease tone too much with Baclofen) Test for tone in the biceps, pronator and supinator, flex and extension of wrist (and rotation of wrist for rigidity) Spasticity is a hard UMN sign – if you pick it up in a dementia patient you know there is diffuse degeneration (such as in multi-infarct dementia and multi-system atrophy, not in AD) Rigidity: implies increased tone of extra-pyramidal origin, it is not velocity dependant, and involves the flexors and extensors equally. You get lead-pipe rigidity where there is increased tone throughout the range of movement, and cogwheel rigidity that you’ll feel on wrist rotation – this is a combination of rigidity and a tremor. If you say rigidity you imply parkinson’s with bradikinesia en tremor
If rigidity is the main problem the patient will c/o falling (usually backwards due to axial rigidity) think of PD. With parkinson’s plus you’ll often get minimal tremor and cogwheel rigidity. A patient with cognitive decline whose complaint is falling – think of MSA
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Paratonia: most dementia patients will have this. It feels as if the patient is resisting you’re movement although the patient may appear relaxed and co-operative. There will also be other signs of cognitive decline. Even NPH can get paratonia eventually. In general, SAY something and then discount it, such as ‘this myelopathy could be due to Vit B12 deficiency, but the intact dorsal columns are against this’. Remember, if the face is not involved the lesion cannot be cortical If all four limbs are weak, but NO FACE involvement, the lesion must be not higher than medulla Beevor's sign is the movement of the navel towards the head on flexing the neck. It is caused by weakness of the lower abdominal muscles, and is characteristic of spinal cord injury between T6 and T10 levels. The upper abdominal rectus abdominus muscle are intact at the top of the abdomen but weak at the lower portion. Thus when the patient is asked to do a sit up only the upper muscles contract pulling the umbilicus toward the head. So if Beevor sign is positive localise lesion at T10, if it is negative the lesion can be anything between T8 and T1 – the next place where you can localise is at the hand (C8, T1) Sensation is about 2 things: 1) quality (sharp vs blunt) and 2) intensity (how strong do you feel it) Reflexes: see end of notes – dr Kakaza tutorial; Babinski – under foot; Shadock – next to foot; Oppenheim – stroke down tibia; Bing – tick on nailbed of big toe; (remember triceps and crossed adductors) End off with cerebellar signs and mention if there are EPS. DERMATOMES: This is the area of skin supplied by a single spinal root C2 – post half of skull C3 – poloneck C4 – level of T-shirt C6 thumb, C7 middle finger, C8 pinky T4 – nipples
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T10 – umbilicus T12 – pubic bone L1 – inguinal ligament L3 – to the knee L4 – to the floor L5 – top of foot S 1 – bottom and side of foot S2-4 - perineum MYOTOMES AND REFLEXES Shoulder – deltoid - abduction C5 Latissimus dorsi – adduction C6,7 Elbow - Biceps – flexion C5, 6 (and biceps and brachioradialis reflex therefor also C5, 6) Triceps – extension C6, 7 Pro-and supinations also C 6,7 Wrist – extension – C6, 7 Flexion – C6, 7, 8, T1 Fingers – extension - C6, 7 Fingers flexions, abduction or adduction – C8, T1 Hip: flexion L1, 2, adduction L2, 3 Hip abduction L4, 5, extension L5, 6 Knee extension: L 3, 4 (knee reflex (L3) Knee flexion: L5, S1 (also ankle eversion)
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Ankle – dorsiflexion and inversion– L4, 5 Plantar flexion – S1, 2 Ankle Reflex – S1 NEUROLOGY SYSTEMS: Neurology is a system consisting of muscle, NM junction, nerve, spinal cord, brain stem, brain. First ask yourself which system is involved? 1) Muscle: Myopathy and myasitis (dermatomyositis, polymyasitis, inclusion body myositis) The patient will complain of proximal weakness (difficulty climbing stairs, getting up out of chair, brushing hair) There will be no sensory complaints. Reflexes will be normal until late (if muscle is severely wasted may decrease reflexes) The onset of myopathy is usually subacute (2-3 weeks), it is proximal, symmetrical, with no bladder problems. If it is very severe the patient may have bulbar symptoms (such as difficulty swallowing) Myopathy: conduction studies normal, treat with prednisone 2) Neuromuscular junction (MG and Lambert Eaton) Always put MG on any differential diagnoses, otherwise you’ll miss it. The key-word here is FATIGABILITY. No sensory complaints Visual complaints are common – especially ptosis or diplopia towards end of day At the end of the meal the patient may experience difficulty swallowing or chewing – the start avoiding foods that needs lot of chewing – rather mince than steak. The voice may also change at the end of the day, get a more nasal quality. 3) Peripheral nerve = neuropathy This is the first time that sensory complaints come in. The patient has distal weakness (long axons first to suffer and die (far from protective cell body) Distribution is glove and stocking Distal reflexes will be diminished Skin may be discoloured, thin, hairless
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There are two major types of neuropathy: a) demyelinating (GBS and CIDP) and b) axonal (diabetes, HIV, alcohol, trigliserides, Vit B12 deficiency, drugs (3TC, stavudine, INH – reversed by pyridoxine) Normal EMG exludes many of the neuropathy’s but not all (small fibres not picked up) Causes of diminished ankle reflex (S1) usually peripheral neuropathy or old age 4) Radiculopathy: Will have weakness and absent reflexes in the myotomes, sensory problems will depend on where the root catches
5) Spinal cord – myelopathy – see dr Kakaza’s tutorial at the end Sensory level Bilateral motor weakness Bladder and bowel involvement May have autonomic level (dry skin abnormal, feel with back of hand) Motor and sensory level will hardly ever be the same 6) Brain stem Checkerboard involvement is the key CN will be affected on the one side (side of pathology), body other side 7) Cortical: Hemi, face will be involved, all on one side 8) Basal ganglia: Will give extra-pyramidal symptoms With stroke there will always be spasticity (not initially) Clinical case: patient with subacute progressive weakness and urinary retention: on examination he had signs of 3-in-1 (myelopathy, radiculopathy, peripheral neuropathy) – myeloradiculoneuropathy: Vit B 12 HIV Copper deficiency In the end the patient had CMV myeloradiculopathy with necrosis of the myelin of the cord and roots, with underlying HIV neuropathy – treated with ganciclovir and ARVs (CMV causes encephalitis in patients with HIV with CD4 < 100) CAUDA EQUINA SYNDROME:
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Urinary complaints, severe pain, may be assymetrical Arachnoiditis may also present like this SYRINX: Always LMN signs
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EPILEPSY: A seizure is a paroxysm (an attack) of synchronised electrical discharges (with summation of discharges due to imbalance between excitation and inhibition) from the brain that cannot be predicted. It is usually random and unprovoked. These summated electrical discharges increase the metabolism of the neurons tremendously, and neurons can be permanently damaged by the demand made on them (glutamate cytotoxicity). Pathophysiology: processing of the impulse at the axon is dependent on the ion channels – mutations in the Na channels cause epilepsy, may be mild (febrile convulsions) or severe – that is why people with epilepsy have ‘good and bad spells’ – channels function about 6/12 before new ones are made – the channels won’t always be abnormal, when normal channels are formed the epilepsy reduce for a while Catamenial epilepsy: Increase in seizures in the week before menstruation When patient presents with first onset seizures – do CT brain to exclude tumor, abscess, bleed, TBI, and do base line bloods and LP – this will give answer in about 17% of cases Therapy is not always indicated after first seizure (only 1/3 will have another seizure), but treat if EEG is clearly abnormal (EEG: can predict the risk of recurrence of seizure) Patient should be advised to keep seizure calendar and to stop alcohol intake If you treat – start with single agent, increase dose until seizures are under control or patient has symptoms of toxicity. Most patients control on monotherapy If it does not control start with other drug, and taper first one when second one has reached therapeutic concentrations. Third drug can be tried, either as mono-therapy or in combination. For partial and secondary generalised seizures Tegretol, Epilim and Lamotrigine can be used For primary generalised seizures Epilim and Lamotrigine are drugs of choice Lamotrigine can be given to women in childbearing years, but is less effective than Epilim Tegretol induces the metabolism of oral contraceptives – must increase dose Epilim has no interaction with oral contraceptive but should be avoided during pregnancy. STATUS EPILEPTICUS: Status: Seizures > 30min, or recurrent seizures without waking up – but in reality any convulsion that lasts longer than 2 minutes is considered to be impending status. Management of status:
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Airway: Position patient on his side with a pillow under his head so that vomit or mucus will run out of mouth (risk of aspiration). Give O2 with mask (rebreath) and
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set O2 at 15 liters of flow (need high flow because you want O2 in bag, not CO2). If O2 sats less than 90% - pt in trouble. Any irregular or obstructive breathing needs airway protection or intubation. Look for signs of cyanosis. NEVER put in airway – it paralysis the tongue and prevent patient from swallowing – higher risk of aspiration. •
Breathing
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Circulation (pulse, BP): pulse rate >120bpm – pt probably hypoxic and in need of intubation. Put up drip immediately – but do not give glucose – because the convulsing brain is in anaerobic metabolism and the glucose will be converted to lactic acid, which will make seizures more resistant to treatment. Only give NaCl.
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Drugs:
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A. Stop convulsion: Lorazepam 4mg ivi stat – beware of respiratory depression and hypotension (10mg diazepam has same effect) - If BP drops give fluids. ** you can give valium 10mg ivi over 2 minutes, and also give lorazepam imi but it will take 30min before action – too long for status. Can mix the valium in a 20ml syringe and give slowly. B. Load: You will load anyway, even if patient stops fitting with the lorazepam. Phenytoin 20mg/kg (1.2 gram) in 200ml saline over 30min or even better, put 4 ampoules in a 20ml syringe and get someone to inject it slowly – 1ml per minute – should be in after 20min. (One ampoule of phenytoin has 250mg/ml – 70 kg person will need 5,5 ampoules) Beware of arrythymia – patient should have ECG monitor – if you give phenytoin too quickly can go in to cardiac arrest. The preservative in phenytoin can also lead to drop in BP Phenytoin precipitates in anything, best is to give it in saline. If there is any glucose in the line the phenytoin will form lumps. Phenytoin is a life saver in status, but Epilim is easier – can give faster and has less side effects. Better to load with valproic acid 30mg/kg (2.4 gram ) Acute side effects of epilim: can increase ammonia level dramatically, and makes platelets dysfunctional – they don’t stick, even if the number of platelets is normal.
Can give 2nd dose of lorazepam if still fitting after loading, and another 10mg per kg of Epilim or phenytoin if still fitting after second dose of lorazepam – if pt still fits needs intubation and anathesia (dormicum at high high high doses) Focal status: patient is awake and talking to you – don’t need to act very aggressively. •
Find cause of status as soon as initial emergency management is completed:
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Do FBC, U&E, CRP, s-osmol, LFT, levels, tox screen (paracetamol), CMP, syphilis, HIV if you can (HIV is epileptogenic in itself, as well as secondary illnesses associated with HIV), CT scan may be indicated, CXR later if aspiration pneumonia is suspected, EEG, urine and LP (30% of patients with status have meningitis) SIDE EFFECTS OF ANTI-EPILEPTIC DRUGS: - USUALLY DOSE-DEPENDANT EPANUTIN: Epanutin is enzyme inducing – other drugs, and itself, metabolised faster S/E: gum hypertrophy, coarsening of face EPILIM: Valproate is an enzyme inhibitor, thus it reduces the metabolism of drugs such as Tegretol and lamotrigine – can lead to toxic levels of other drugs Common: GIT (nausea, vomiting, constipation, diarree), sedation. Is considered to be a major teratogen – all females in reproductive years should be on folate. Uncommon: tremor, interference with platelet function, hepatotoxicity, pancreatitis, rash (especially in combination with lamotrigine), hair loss, increase in weight Toxicity: cerebellar symptoms (symptoms of co-ordination) CARBAMAZEPINE: Common: Sedation, ataxia, dizziness, GIT, dry mouth common Uncommon: skin rash (Steven Johnsons), SIADH with low sodium and water retention, bonemarrow suppression with agranulocytosis, thrombocytopenia, aplastic anemia, osteoporosis due to reduced Ca absorption Toxicity: nystagmus, ataxia, confused, blurred vision, speech disturbance, drowsy, hallucinations, abnormal movements Because serum levels of drugs do not correlate with concentration in CSF it is not recommended to do levels for therapeutic reasons. Indications for levels would be 1)suspected non-compliance 2) suspected toxicity 3) to determine baseline level of effective concentration CRANIOPHARYNGIOMA: Slow growing, calcified, cystic tumor Occupies suprasellar region Arises from remnants of the craniopharyngeal duct Has benign histology but malignant behaviour (invades tissue and recur after surgery) Usually in kids and older adults (60y+) Accounts for 1-3% of intracranial tumors
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Excellent survival in young patients, not so good in older patients Symptoms only when tumor is 3cm plus – usually then had tumor for 1-2 years Symptoms: Headache: dull, continuous, positional Endocrine problems: 40% have hypothyroidism with weight gain, fatigue, cold intolerance, constipation 25% have adrenal failure with low BP, low glucose, high potassium, lethargy, vomiting 20% have diabetes insipidus with poliuria and polydipsia 90% have Erectile dysfunction or amenorree depending on gender Visual problems: often; if tumor is pre-chiasmal – optic atrophy with reduced acuity and fields If post chiasmal: hydrocephalus with increased ICP and papil edema with double vision. CNS LYMPHOMA: 3% of all brain tumors Very common in HIV when CD4 drops below 50 Males predominate, usually 50+, but younger in HIV patients CNS lymphoma is an AIDS defining illness and ARV reduces the risk Etiology: Unknown, possibly chronic stimulation of lymphocyte clones by EBV >50% of the tumors have Human Herpes 8 in them - ? significance – HHV8 also associated with Kaposi sarcoma Pathology: Mostly B-cells, arise in, and is confined to the CNS 25-50% of patients will have multiple lesions that may look like mets Tumor often grows around small vessels, and ocular involvement common Clinical: Frontal lobe mostly involved – neurocognitive presentation with dementia and lethargy. Convulsions are not common because it is rather the deep structures that are affected, and not the seizure-prone cerebral cortex Blurred vision common symptoms Focal deposits on cranial and spinal nerve roots may lead to neuropathy and radiculopathy Diagnoses: FBC, HIV, T. gondii serology (looks like toxoplasmosis on MRI with smooth, round dense lesions with ring enhancement) (toxo and lymphoma often co-exist in AIDS) Rx with radio- and chemotherapy, not surgery – has poor prognosis, dead after 3/12 Clinical case: 23 year old on TBRx, c/o pain in feet past 3/7 with weakness in both legs/ Think: •
Peripheral neuropathy
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GBS
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Myelopathy
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ADEM
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Devic (optic neuritis with cervical spine fallout) – is common with TB
Can differentiate GBS from other causes of neuropathy with EMG. If both eyes are affected, think gaze palsy first, not cranial nerves Gaze palsy: if stroke is in the frontal lobe, pt will look toward the lesion Horisontal gaze – FEF and pons; FEF supplied by ACA Vertical gaze – midbrain Motor strip supplied by MCA Tongue has bilateral supply in most people, and will only deviate with brain stem lesions.
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STROKE Stroke: acute onset of neurological deficit with focal signs, presumed to be of vascular origin (infarction, embolus, bleed) Drugs can cause stroke (diet meds, cocaine) also pregnancy and hypertension DW: white is pathology ADC superimposed on this – now pathology is black 85% of strokes occur in the anterior circulation, 15% in posterior circulation Strokes can be classified according to vascular supply (ant vs post) or large vessel, small vessel, embolic stroke and ‘other’, or according to time (hyperacute, acute, subacute and old) If no corneal reflex – hard sign of cranial nerve V lesion – would expect a dense sensory deficit VII palsy: upper bit of face gets bilateral supply – stroke in one part of brain – forehead will still be okay due to bilateral supply from other cortex – UMN only lower half of face affected Brainstem: VII and VI next to one another – in brain stem stroke often VII and ipsilateral VI (lateral gaze affected) 80% of patients with stroke will have an acute hypertensive crisis within 24 hours - it is possibly due to the autonomic system. BP should not be dropped too low – no perfusion of brain, because auto-regulation does not work and the perfusion depends on the MAP. The area around the stroke is called the penumbra – no electrical activity post-stroke in this area, but the cells are still viable – do not drop BP too low, otherwise you’ll lose this area Don’t treat HT unless the systolic is >180 and the diastolic is >110mmgHg. Brain stem stroke often a lot worse on post mortem than on MRI. Bleed vs thrombus: bleed will give more patchy sensory loss, because blood often just push fibres away, do not affect all the fibres adversely, whereas thrombus often leads to occlusion with area of necrosis and more fibres affected. If you want to detect facial sensation in an unconscious stroke patient can do corneal reflex (not completely absent, but reduced), or tickle in the nose with cotton wool. TIA is a neurological deficit that will completely resolve within 24 hours, usually within 20 minutes to one hour TIA score: a patient who presents with TIA is at high risk to develop a stroke, and should be worked out within 2/52. Risk factors that TIA will progress to stroke includes: atrial fibrillation, >60 years of age, hypertension, diabetes
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TIAs give NEGATIVE PHENOMENA (epilepsy gives positive phenomena) such as Blind (instead of lights) Weakness (instead of jerking) Numbness (instead of tingling) Investigations of stroke patient: CXR: aspiration LFT: if deranged can increase risk of bleeding Cholesterol: if too low can increase risk of bleeding (cell wall integrity involved), if too high – atherosclerosis Glucose: to exclude DM FBC: infection, polycythemia, thrombocytosis (any increase in cells will cause increase in viscosity with risk of thrombosis) ESR: inflammation and infection, Ca, auto-immune disease (often cause of young stroke), severe anemia Anti-nuclear antibodies U&E: end organ damage secondary to hypertension, electrolyte disturbance Thyroid functions: hyperthyroidism may give arrhythmia - stroke RPR, TPHA Treatment of stroke: Dispirin is an anti-platelet – prevents clots Simvastatin (Zocor) functions to stabilize the plaque (don’t give if cholesterol is 100 TB, malignancy, temporal arteritis, rheumatoid arthritis and polymyalgia rheumatica SECONDARY HEADACHES: Due to SAH, glaucoma, infective (meningitis or referred pain from sinusitis), post-traumatic gliosis, tumor, drugs (codeine, steroids, ro-accutane, anti-epileptics, anti-hypertensives), low pressure headache after LP. Straining your eyes does NOT give you a headache! Mx of low pressure headache: Lie down for 4-6 hours, take in lots of fluid, strict bedrest, caffeine. The headache may last for days. Can be avoided by the use of thinnest needle, and poke as little as possible Dr Kakaza ward round: Motor Neuron Disease History: progressive difficulty in walking, speaking, swallowing O/E: combination of UMN and LMN, although you also get MND that is predominantly LMN or UMN. About 1% of patients with MND also have cognitive decline. MND is usually a pure motor pathway problem – it starts with the pyramidal cells in the cortex, if the die-back is extensive you’ll get other frontal lobe signs. Look for atrophy and fasciculations (remember snuffbox muscle on hand is called 1 st dorsal interossieus muscle, and on palm the thumb muscle is called thenar muscle.) If you have JUST LMN – think CIDP, syrinx (cranial nerves may also be affected), MND, SMA (different forms – can present in baby or in adult – only affect the anterior motor neuron horn cells) Must exclude hypothyroidism, hypercalcemia, AIDS, Lithium toxicity in any case of LMN weakness – can look exactly like MND. What diseases can give you swallowing problems? •
ADEM
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Myasthenia Gravis
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Strokes
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GBS
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Myopathy (dystrophia)
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MND (progressive bulbar palsy)
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Botulism
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(MG and GBS both respond to IVIG)
Diseases that gives multisystem neuro involvement: •
TB
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Alcohol
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Syphilis
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HIV
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MS
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Vit B12 deficiency
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DR KAKAZA – TUTORIAL NUMBER 1: CRANIAL NERVES Cranial nerve nuclei in the brainstem are regarded as LMN. Remember cortical problems – ALL lesions, including CN, will be on contralateral side CRANIAL NERVE I: OLFACTORY Fibres start in nose, through cribiform plate, through orbito-frontal area, to temporal lobe 1) Anosmia: Common problem, but patient will often rather complain of abnormal taste than of anosmia Usually due to smoking or sinusitis Sometimes whip-lash injury (even a mild injury can cause thin fibres to break as they go through cribiform plate) Anosmia may also be due to neuro-degenerative disease such as Parkinson’s. (The first thing to go in Parkinson’s is the sense of smell – may precede other symptoms by years) – this is because the small, thin fibres degenerate first. Meningioma in orbito-frontal area also causes anosmia 2) Abnormal smell: Patient may complain about an episodic bad smell –usually part of epilepsy DIGRESS TO EPILEPSY: First determine whether it is partial or generalised Classification of epilepsy: Partial seizures: Simple (no loss of consciousness) Complex (consciousness impaired) Evolving to secondary generalised convulsions Generalised seizures: Absence seizure Tonic Tonic-clonic Myoclonic Atonic Epilepsy, migraine and mood disorders often run in families, and may overlap in one patient – this is because the pathogenesis of these diseases is almost the same, namely they are all channelopathies. Because channels are not permanent the symptoms may be episodic. New channels are formed every few months (about 6/12) and they don’t have the same degree of
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abnormality every time (you have each time a chance to make normal channels) – it is because of this reason that patients may report ‘bad spells’ and ‘good spells’ that may lasts for months. Depending on the dysfunction of the channel the patient may have one, 2 or all 3 of the diseases. The channels involved are mainly Na, Cl, and Ca depending on the gene Epilim works on multiple channels (Na, Cl, GABA) Partial seizures (aka focal seizures aka auras) Partial seizure implies that the seizure originates from a focus – partial seizures and focal seizures are interchangeable terms. During a simple partial seizure the patient is totally awake and is able to tell you what is happening Motor SPS: If seizure presents with motor phenomena it means the seizure originates from the motor cortex in the precentral gyrus, frontal lobe. Sensory SPS: Jacksonian march: sensory focal simple partial seizure: pins and needles go up the arm and then down the leg. Special sensory SPS: Simple partial seizures can also be autonomic or special sensory (smell, or hear bells) Simple partial seizures used to be called ‘auras’ – it was incorrectly thought that this happened before the seizure The way a simple partial seizure presents tell you where it originates SPS can repeat, up to 10x per day, and then go into secondary generalised seizure Prodrome to a seizure is not the same as an aura (an aura IS the seizure). The patient may say during the prodrome – I feel funny – when I feel like this I know I’ll get an attack within 2/7 ‘AURA’: An aura is a subjective sensation may be accompanied by changes in mood and behaviour Can find in epilepsy, TIA and migraine (must differentiate from panic attack) How to differentiate: the aura of a migraine takes long to develop, lasts long, up to an hour, and it does not recur; whereas the aura of epilepsy is instantaneous, never lasts longer than a minute but may repeat The aura of migraine and epilepsy both have positive phenomena such as seeing lights and tingling sensation. Visual aura in migraine is common (30%), can see shapes with lines. Not always easy to differentiate aura of epilepsy from panic attack – epilepsy can also give you anxiety and elation Visual symptoms in epilepsy can be just light, or well formed pictures such as seeing a fire COMPLEX PARTIAL SEIZURES:
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Used to be called TLE The patient is awake but is unaware of what he is doing They will look confused (other people will realise something is wrong) They may have automatisms: this is what you can do automatically without thinking, because you do it every day, such as driving a car, packing and unpacking cupboards Automatisms are often used as a defence in court, but you CANNOT PRE-MEDITATE while you are having a seizure. You can reverse over someone while having an automatism if you’re driving every day, but you cannot go to cupboard and get knife and stab someone. There are often visual symptoms as part of CPS The term TLE is not used anymore, because extensive EEGs showed that >50% of ‘TLE’s originates from temporal lobe, the rest originates from the frontal lobe or parietooccipital junction. Most frontal lobe epilepsy will also present as CPS – the patient classically assumes a ‘fencing’ posture. The CPS is often preceded by a SPS (simple partial seizure/aura) where the patient may feel an egigastric sensation, have a bad taste in the mouth, or smell something bad. After this they will have a ‘blackout’ according to them, but they don’t fall and will now have the CPS. Eyewitnesses will say that the patient was awake, but was behaving strangely, and would do or say inappropriate things (i.e. one lady complaint that her husband would get up from dinner table to get the comb, and then sit combing his hair while they have dinner), or patient may go out of the house to undress on front lawn – this may easily be confused with dementia!! If the CPS lasts about a minute, and the patient is post-ictal and confused afterwards, and the patient get several attacks per day, very easy to confuse with dementia. Is called Epilepsy Partialis Continua, and is treated with low dose Tegretol (200mg bd) EEG in CPS will often only show focal slowing in temporal lobe, but no focus. If you do a sleep EEG you may be lucky and see a ‘spike and wave’ pattern. When they come to from the CPS, they are in a post-ictal state of confusion and wkll have amnesia for the event. You must be able to differentiate an absence seizure from a CPS: Absence seizures are very rare in adults (kids uruadly outgrow them) Absence seizure is very shOrt – never longer than 30 seconds whereas SPS will lcst at least a minute or longer. If a patient has an absence seizure whilst valkéng he will stop in the middle$of the sentence, look blank for 20(seconds and then resume!the senTence EXACTLY where he left off. Th%re will be no confusion. In CPS the pati%nt will be confused afterwards. Complex partial status is very difficult to diagnose, and can easily be"confused with$psychosis – but what the patient does (the automatism) will be cyclical – they’ll
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repeat what they’re doing, maybe with short lukid periods in between, wiereas psychotic behqwiour is usually more disorganised. Ôhe activity will also not involve you, they won’t fight unless you bother them. *j any rePeated strange behaviïur – think epilepsy Absence seizures can be!treated with ethosuximide, a finicky drug that ONLY works for partial seizures, whereas Epilim works for all forms of epilepsy (partial and generalised) Tegretol is the drug of choice for partial seizures (whether SPS or CPS) and is considered the gold standard for partial seizures, even though epilim is often used due to the sideeffects of Tegretol (more sedation and dizziness) In adult patients generalised epilepsy is more common that partial seizures, and CPS is more common than SPS (GE>CPS>SPS) (SPS is only aura, CPS aura and automatism) In elderly patients (>60 years) CPS are the most common form of epilepsy (more common than generalised epilepsy) – often misdiagnosed as dementia – must really always do EEG before you diagnose dementia with strange presentation If you give a confused elderly patient lorazepam and he becomes alert – diagnoses of epilepsy made Causes of epilepsy: 18-30 years – usually idiopathic 45-60y – usually due to stroke, sometimes tumors >60y – usually due to neurodegeneration HIV has higher incidence of epilepsy than the general population
GENERALISED SEIZURES: Definition: Either loss of consciousness (will fall down), OR EEG shows generalised firing in the hemispheres. A patient with CPS will NOT fall down, unless they have secondary generalised seizure. Generalised seizure implies that the hemispheres are equally involved from the onset of the seizure. Types of generalised seizures: 1. Absence seizures 2. Generalised tonic clonic seizures (grand mal) 3. Tonic seizures (stiff and fall down) 4. Clonic seizure (immediately jerking with no initial stiffness 5. Atonic seizures – just loses tone and fall. Myoclonic seizures: arms may lift once as if the patient had a fright, they do NOT lose consciousness. It usually occurs as part of a seizure syndrome (together with generalised tonic-clonic). Treatment is important – myoclonic seizures do not respond to Tegretol or phenytoin, and the generalised tonic clonic seizures may actually worsen – if myoclonic
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seizures are present you should treat with Epilim. ** a sudden jerk just before falling asleep is called physiological myoclonus. Surgery for epilepsy: It has the side-effect of severe depression in all patients that may last up to two years – patient needs psychiatrist before and after surgery Patient who had surgery won’t ever be off meds – just possible to taper down to one drug Surgery is not a permanent solution: seizures come back after 5 years DR KAKAZA – TUTORIAL 2 (18/1/2011) CRANIAL NERVE II: Look for visual fields, visual acuity, light reflex and retina The patient’s main complaint is usually ‘I can’t see’ The first question you must ask is: is this in the eye, or behind the eye? The pupil reflex answers this question If the pupil is dilated the cause of blindness is in the eye, if the pupil is reactive the cause of blindness must be in the brain Direct light reflex: afferent is from CN II – sends info to the EWN in the midbrain, from where info goes out bilaterally to both eyes to give the consensual light respons. If CNII is disrupted there will be an afferent pupillary defect – the pupil will be big and won’t contract. If the lesion is in occipital lobe (lesion behind the reflex) – the direct and consensual reflexes will be intact. You need a bilateral lesion to be blind from occipital pathology (lesion in basilar artery). If there is swelling of the occipital lobes, such as you find in eclampsia and hypertensive encephalopathy with a sudden increase in BP, there may be sudden onset of blindness. Unilateral blindness – the problem is not in the occipital lobe, must be in the retina or optic nerve (the pupil will be dilated) MARCUS GUNN PUPIL: Afferent pupillary defect – shine light in normal eye – both eyes will constrict (consensual light reflex from EWN) – then move light over to the abnormal side – both pupils will dilate (is dilating because light is moving away from normal eye, normal eye assumes the primary position (as does the abnormal eye due to consensual reflexes) and abnormal eye does not pick up the light shining into). This is due to an optic nerve defect in one eye, with reduced entry of light into the nerve. If the pupil goes a bit smaller, then bit bigger again – normal phenomena, much like hippus.
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Fundoscopy: look at retina for swelling or atrophy of disc – with swelling the margins will be blurred and vessels engorged.
If the disc is swollen, you must differentiate between
papiledema and optic neuritis: Papiledema has NORMAL visual acuity – loses vision only at late stage when they have optic atrophy. Optic neuritis: patient will have reduced vision, may be blind (sometimes central scotoma, which is blind spot in the middle of the visual field). Optic neuritis is not an uncommon condition with acute onset of vision loss and pain in the eye on movement. It will start in one eye, and often move to the other eye. The commonest cause is demyelinating lesion, such as focal ADEM (called sight restricted ADEM) which is usually bilateral, or MS, where the neuritis will occur in the one eye, then in the other, but NEVER in both eyes at the same time Sight restricted ADEM: •
Acute demyelinating
•
Monophasic
•
Post – infectious
•
Can involve whole brain, or just brainstem or just optic nerve
•
Rx with steroids
Optic atrophy: the patient will have 1) gradual visual loss, a 2) dilated pupil and a 3) pale disk and 4) less than 7 small vessels entering disc, With primary optic atrophy the margins are crisp but with secondary optic atrophy due to papiledema the margins will be blurred. Sometimes you’ll see a pale disk with normal visual acuity – this may be normal variant of disk. Visual fields: test all the quadrants Commonest problem is bitemporal hemi-anopia (due to pituitary lesion pressing on the optic chiasm) Homoanymous hemi-anopia – lesion in optic radiation Quadrantanopia (only ¼ of visual fields involved) – occurs with lesions in the T, P or O lobe – usually Occipital lobe Can also do confrontation test in patient in ICU, blind patient Sensory extinction: with double simultaneous stimulation: patient not aware of the stimlulus on one side. Stimulus may be touch; sound; visual input. If you have a stroke with hemi-anopia – means BIG lesion – involves parietal lobe DIGRESS TO MULTIPLE SCLEROSIS:
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Multiple sclerosis (MS) is an immune-mediated (both cellular and humoral components), inflammatory and demyelinating disease of the CNS neurodegenerative disease of the CNS responsible for a significant amount of disability worldwide. Types: relapsing – remitting course – most common Secondary progressive (start off as relapsing remitting) Primary progressive – bad, poor prognosis History very important if you suspect MS – patient must have had diverse neurological complaints over a period of time (lesions disseminated in time and space). For instance may have had an episode of visual problems that had improved, then episode of hemiparesis that had improved. (If ALL the episodes involved the same site, i.e. all episodes R hemiparesis – rather think vascular (TIA). The different episodes in ‘time and space’ had to be at least 6/12 apart to differentiate it from ADEM which may also relapse for a while. On Examination: MS is an UMN condition, often accompanied by clumsiness and eye signs. Look for subtle signs Eye signs: Optic neuritis Diplopia INO (internuclear ophtalmoplegia) – MLF lesion Trigeminal neuralgia Often don’t see disc swelling in MS – the demyelination is retrobulbar and fundoscopy normal INO: If you look to the Right, the Right eye will go out with nystagmus, but the left eye does not go in. The pathology is in the MLF (medial longitudinal fasciculus) (Vertical gaze controlled by dorsal midbrain: in PSP there is destruction of the dorsal midbrain, and the patient will be unable to look up or down (with normal aging the upward look is also impaired, but can always look down) Horisontal gaze is controlled by the FEF (frontal eye fields, ACA) that will send impulse to PPRF (pontine reticular formation on the contralateral side. The FEF pushes the eyes to the opposite direction (Left FEF pushes eye to the right horizontal direction) From the PPRF the connection goes to the VI on that same side, and with the MLF to the III on the side of the FEF (MLF is between VI and III). Plague of MS loves the MLF for some unknown reason. You don’t get full III fall out – only the little bit that goes to the medial rectus is involved (MLF only involves the medial rectus)
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Why does the eye that is looking outwards have nystagmus? This is an attempt of the brain to avoid diplopia INO can be unilateral or bilateral Horisontal gaze palsy – if lesion is in frontal lobe the eyes will look towards the lesion (function of the FEF is to PUSH the eyes AWAY), if lesion is in the pons, the eyes will look away from the lesion. Horizontal gaze palsy can be due to lesion in frontal lobe, or due to lesions in the pons such as Ca or tuberculoma of central pons, and central pontine myelinolysis. Initially MS will recover after an episode, but over time residual symptoms will develop. The pathogenesis is that the myelin sheath (made by the oligodendrocytes) is attacked, but not the oligodendrocytes. Initially there is remyelination of the axons, but over time there is a dying back of the oligodendrocytes, and no more remyelination occurs. In the primary progressive type of MS there is death of the oligodendrocytes from the start. Devic syndrome: Black patient, bilateral optic neuritis, signs of myelopathy DIAGNOSES: 1) Primary diagnostic test is MRI, the criteria is called Mc Donald criteria (you need periventricular plagues, also at least one infra-tentorial (cerebellum, brain stem or spinal cord) T1: (CSF dark on this one and can see the anatomy well) old plagues will look like black holes. T2, T2 flair and gadolinium: active plagues MRI often done with galidinium - active lesions will light up. With MRI not really necessary for the clinical criteria of ‘disseminated in time and space’ because you’ll pick up old, previously asymptomatic lesions (was in silent area of the brain) even with first symptomatic presentation and can start with treatment early.
2) LP: will have increased protein (more than 1 gram) and no cells – called cytoalbumino dissociation. Do oligoclonal bands and IgG index (send blood with the CSF sot that the ratio between the IgG in the blood and CSF can be determined. (It should be the same 1:1, but intra-thecal synthesis of antibodies occur in MS, with production of IgG in the CSF. This is not specific for MS – it will also be found in meningitis and in auto-immune diseases. 3) Evoked potentials – visual, auditory and somatosensory – will pick up subclinical deficits due to previous attacks that the patient was unaware of. There will be slow movement of the impulses – will prove dissemination in time and space. TREATMENT OF MS:
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1) First episode (or any acute attack) is treated with steroids Solumedrol 500mg ivi daily x 5/7 (doesn’t need Ca and Slow K with short courses, but always give ulsanic to prevent gastritis, patient may also need short term bzp for insomnia caused by steroids. Remember never to treat optic neuritis with oral steroids – always ivi – was shown that people on oral steroids actually did worse than people who did not receive any medicine. patient TCB 3/12, repeat MRI with gadolinium – why? Because active plague remains active for 3 abnormal), pe-pe-pe soft CN IX, X: weak soft palate but brisk gag CN XII: spastic tongue, no atrophy, no fast alternating movements, la-la-la is monotonous with merging syllables. Look for UMN in limbs as well as LABILE EMOTIONS Nasal voice due to weak soft palate CAUSES OF PSEUDOBULBAR PALSY: (MAM) Multi-infarct dementia (multiple, bilateral strokes) MND (ALS) MS Butterfly glioma INVESTIGATIONS FOR PSEUDOBULBAR PALSY: MRI BULBAR WEAKNESS: this is LMN involving cranial nuclei in the medulla and pons. Corticospinal tracts often also involved (UMN). Cranial nerves V, VII, IX, X, XII involved. Therefore if face is LMN, and limbs are UMN – think brainstem! If LMN: BULBAR palsy – the tongue is atrophic early on, with fasciculations ( the patient must keep the tongue in the mouth when you look for this – shine your light inside the mouth and look at resting tongue) (Fasciculations – main cause is disruption of anterior horn cell – multiple fasciculations in polio. Bilateral CN V: weak, no jaw jerk Bilateral CN VII: weak, no snout Bilateral IX, X: weak soft palate, no gag Bilateral XII: atrophy and fasciculations CAUSES OF BULBAR PALSY: MND or brainstem tumour, such as pontine glioma, also TB granuloma most common causes, also ADEM and listeria ** If you talk about bulbar palsy you just say the soft palate is weak – the cause can be anything – does not have to involve the brainstem bulb.
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** careful with forehead in CN VII: cannot use if there is bilateral involvement of VII. With bilateral VII can only differentiate between UMN and LMN with the snout and glabellar taps. ** A mute patient may have severe dysarthria (even seen in Parkinson’s) , or severe aphasia (global or Broca’s) or hysteria. CN X mainly supplies the vocal cords DYSARTHRIA: 1) Dysarthria due to Cerebellar causes: Voice is monotone (aprosody – no melodic intonation) and staccato, pt says pe….te….ke… instead of peteke 2) Dysarthria due to Bulbar palsy: The patient will have slurring speech, with words merging into one. Speech will also have nasal quality (air escapes through the nose due to weak soft palate) – is called Donald Duck speech. 3) Dysarthria due to Parkinson’s disease: Soft, monotone voice called dysphonia 4) Dysarthria due to Pseudobulbar palsy: Weak palate with slow la-la-la Spastic tongue – talks as if hot potato in the mouth •
If you ever make diagnoses of multi-infarct dementia – look for subtle signs of UMN lesions and stepwise deterioration
•
If you have a patient with cognitive decline and UMN signs – think multi-infarct dementia or MSA.
CRANIAL VII: Nucleus of VII in medial pons. Motor division supplies all muscles of facial expression Sensory : small patch behind ear Special sensory: anterior 2/3 of tongue for taste (V is sensation of anterior tongue) Stroke in brainstem – will have LMN VII and contralateral corticospinal involvement Cortical stroke: Will have UMN VII and ipsilateral corticospinal involvement of body DR KAKAZA 25/01/2011 VII CONTINUES: VII can be affected in the brain stem, then in ear. Bell’s palsy is inflammation of the nerve as it goes through the bony canal – no space for swelling and nerve is compressed. Bell’s Palsy implies the cause of the paralysis is idiopathic. If it is secondary to sarcoidosis, HIV, TB or herpes you’ll say ‘CNVII fallout due to x’.
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Must look in the ear and soft palate for vesicles – give acyclovir in addition to steroids only if vesicles are present (Ramsy Hunt syndrome) Rx of Bell’s: Steroids – must give in first week. Prednisone 60mg daily, taper by 5mg daily Bells’ palsy – patient has problem with eye closure due to weakness of orbicularis oculi – give Tearsnaturel and eyepatch to protect against ulceration. When the patient closes eye a bit of white may be visible – Bell’s sign. If it is a UMN VII the eye may be partially affected Bell’s recover in 6/52- 3/12 EMG only indicated if patient not better after 3/12 Because Bell’s palsy is probably from viral origin VII is not the only nerve affected - may affect V and palate, but symptoms and signs more obvious with VII due to compression of nerve. UMN VII Forehead spared (may be a bit weak, but can at least close eyes and frommel voorkop, even IF NOT AS good as other side. Can’t smile on command, but can smile at joke (smile muscles also innervated from limbic system) LMN VII: Taste is affected (taste fibres join nerve late) Can’t smile at all Hyperaccusis – branch to Stapedius muscle affected whole face involved, Bell’s sign BILATERAL FACIAL WEAKNESS: As yourself BULBAR or PSEUDOBULBAR (LMN or UMN) Will decide this with snout reflex – it is a frontal release sign And glabellar (both positive in UMN lesion) Will probably find brisk Jaw jerk as well CRANIAL NERVE IX and X Supply the soft palate Both have motor and sensory components But IX more sensory than motor and X more motor than sensory If problems with IX or X the patient will complain of a soft voice, nasal voice and dysphagia that is worse for liquids than for solids. Fluid will come out of nose. When you look into mouth, look at the pillars and uvula to see if it is in the centre (assymetrical uvula usually due to past tonsillectomy). Ask the patient to say AHHH
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Soft palate must contract and lift up, but the uvula must remain central - if is pulls to the side, knows it is pulling towards strong normal side. Unilateral weakness of the palate is usually LMN (may be problem in brainstem), because if it is due to stroke – bilateral supply will take over – weakness not noticeable BILATERAL WEAKNESS OF PALATE: May be bulbar or pseudobulbar. With AHHH it will go up nothing or very little – only way to differentiate between UMN and LMN is with gagreflex – it will jump up with UMN, and not move with LMN.
(dus, in pseudobulbar, will find all the UMN reflexes, namely snout,
glabellar, gag, jaw) LATERAL MEDULLARY STROKE: (WALLENBURG syndrome) This patient is not weak – the main problem is vertigo This is the MOST COMMON BRAIN STEM STROKE V: sensory - ipsilateral numbness Spinothalamic – contralateral numbness of arm and leg Sympathetic fibres: Horner’s ipsilateral IX, X: dysphagia and dysphonia – ipsilateral soft palate weak Cerebellar peduncles – off balance – will fall towards lesion Diplopia due to skew deviation VIII – nausea and vomiting Vertigo is the sensation of movement, patient will say ‘i’m dizzy’ True dizziness is for the cardiologist Vertigo is for the ENT or neurologist
Glossopharyngeal neuralgia IX, X involvement Excruciating pain on swallowing – also due to vascular loop, Rx with Tegretol, triptilline, lyrica, MRI may help with diagnoses (may visualise loop) Marchiafava Bignami – necrosis of CC DR KAKAZA – TUTORIAL 4/2/2011 Summary of patient with a stroke in the cerebral hemispheres: In the history ask about onset, function, localisation and high risk factors
1) ONSET: The history will be that of acute onset – the patient may develop the deficit out of the blue, or wake up with the deficit.
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Acute onset – always think vascular cause, although a stroke may also have a STUTTERING course, in which case the patient was having emboli, or had progressive thrombosis, but the deficit will still usually occur over 24 hour period. If the history is that of progressive weakness, rather think tumor or granuloma (of which toxoplasmosis and TB are the most common causes)
2) MAXIMUM WEAKNESS: Ask the patient about the period of maximum weakness – what could he not do then? Is it staying the same or getting better now? (function)
3) DISTRIBUTION OF WEAKNESS: get the distribution of weakness from the patient (drooling saliva, numbness, couldn’t move) – you can make diagnosis of stroke, as well as localise it, on history alone.
4) HIGH RISK FACTORS TO ASK ABOUT: Hypertension Diabetes mellitus Smoking and alcohol (vessel hardening and atherosclerosis) HIV and ARVs – HIV causes stroke by means of a) vasculitis b) endocarditis c) hypercoagubility, d) cardiomyopathy e) thrombocytopenia with bleeding. ARVs cause accelerated atherosclerosis Heart disease: young black patient from rural area – think rheumatic fever; older people think atrial fibrillation – which is often intermitted and can therefore be missed on clinical exam History of previous stroke, especially if they’re young Familial vasculopathy (relatives with heart problems, strokes) The young stroke = stroke in patient less than 45 years:
1) Could be due to contraceptives: estrogen may cause idiosyncratic reaction during the first 3/12 of use where it lowers prot C and S and therefore causes hypercoagubility
2) Pregnancy is a hypercoaguble state with increased risk of thrombo-embolism (Remember in pregnancy as well the lower albumin accelerates drug clearance – often need higher doses in pregnancy)
3) Coagulopathy: the most common one is anti-phospholipid syndrome (clotting disorder, auto-immune based)– this can be an inherited trait that occurs in isolation, or it may be associated with other diseases such as SLE. This is the only syndrome proven to cause BOTH arterial and venous occlusion, therefore you’ll often get history of previous DVT (remember a DVT will cause PE, not stroke, unless person has a right to left shunt). There may also be a history of abortions (the venous blood in the placenta clots)
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If you don’t find the cause for a stroke in a young patient it is actually good news – they have less chance of having another stroke, whereas if you do find a cause in a young patient – has a high risk of having another stroke in future. Coagulation profile: prot C and S, anti-phospholipid Ab, homocysteine, factor V Leyden, beta-2 glycoprotein – these are specialised tests, not first line 4) low Hb may indirectly lead to stroke – body will try to keep viscosity normal in severe anemia – easiest bloodcell to make is platelet – that’s why anemic patient sometimes has thrombocytosis, which is risk factor for stroke (any increase in viscosity is risk factor, also polycythemia vera, leucocytosis)
5) hyperthyroidism – may lead to intermittend atrial fibrillation (not necessarily detectable on physical exam) ON EXAMINATION OF THE STROKE PATIENT: 1) ALWAYS do a cognitive score. A strategically placed stroke can cause dementia with one stroke, i.e. if medial temporal lobe is affected (MCA) Bilateral frontal strokes happen in patients who have only one stem of the ACA – if thrombus lodges in this stem – bilateral supply cut off – this may cause Kluver Bucy syndrome (hypersexuality, hyperorality and placidity – can have conversation with the person, seems okay, then they turn around and eat something from the floor) Pontine stroke, even small one, may cause auditory hallucinations (peduncular hallucinosis) Make sure the patient is not delirious, does not have APHASIA, and went to school before you comment on the cognitive score. 2) Bloods to do in stroke patient: FBC: for increase decrease in cells U&E: kidney failure due to HT, or as cause of dysfunctional platelets with bleed Thyroidfunction: s-glucose: DM risk for stroke RPR and TPHA: endarteritis obliterans and vasculitis Auto-immune screen: ANA, ESR, anti-DNS Ab second line test Lipogram: risk for atherosclerosis APHASIA: Due to lesion in the left hemisphere – Broca’s dictums says ‘even if someone is lefthanded, the speech area is still probably in the left hemisphere’. When you hear first: Ear (hears sounds, not words) – sounds to association area for primary interpretation – Wernicke’s (further interpretation) – arcuate fasciculus – Broca – motor area for speech. (From Broca fibres also go to lexicon to get words if
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you want to respond, if you just listen and do not respond it stays in Wernicke, if you just write it goes to parieto-occipital lobe) When you speak first: it starts in Broca, not in Wernickes’ – this you evaluate with spontaneous speech (pt tells you the history) If it is non fluent: why? If the patient struggles to find a word – the problem is Broca’s conduit to lexicon is broken 1. Broca’s /Expressive /Motor aphasia: Pure Broca is very rare – most strokes will involve both Broca and the arcuate fasciculus, often with Wernicke’s involved as well. With a Broca’s aphasia the patient is often very depressed, because he is aware of the deficit – he is trying to make himself understood but cannot express himself. The reason for this is that the retrieval of words from the internal lexicon in the parietal lobe is affected (Broca is the conduit between the lexicon (dictionary) and the motor speech area) The patient will speak in a non-fluent way with short sentences, often just verb and noun, often has to describe something rather than naming it (thing u write – instead of pen), he may use neologisms, paraphasing (substituting a sound or a letter within a word – you’ll still recognize the word, although it is not exactly correct)) and circumlocutions. Despite the problem the patient has to find a word you’ll understand what they’re trying to say. The difficulty the patient has expressing himself will also manifest in his writing. A patient with a stroke in Broca will have a right hemiparesis – don’t diagnose aphasia without this. Broca also difficulty repeating. 2. Wernicke’s /receptive aphasia: The patient CANNOT COMPREHEND and cannot PRODUCE MEANINGFUL language. The patient is initially not depressed – it takes him a while to realise that no one understands him, and that he does not understand other people. Spontaneous speech will be fluent but will not make any sense, will be unrelated to the topic. The patient will keep to common courtesy of dialogue – will make eye contact, wait for you to finish speaking before he starts again. The patient cannot read or write or tell you what the matter is – make very sure the patient is not confused due to delirium before you diagnose this. Will have difficulty with repeating because he doesn’t understand 3. Global (combination) aphasia:
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They are marked by a severe impairment of both understanding and expression of language. The symptoms of global aphasia are those of severe Broca's aphasia and Wernicke's aphasia combined. It is usually associated with a large lesion in the perisylvian area. It involves a "left side blowout" which includes Broca's area, Wernicke's area and the Arcuate fasciculus. There is an almost total reduction of all aspects of spoken and written language, in expression as well as comprehension. Improvement may occur in one or both areas (expressive and receptive) over time with rehabilitation. When injury initially occurs to all of these areas, the progression starts out with Global aphasia in the first 1–2 days due to brain swelling (cerebral edema). From there, it evolves into Brocas or Wernicke's aphasia for 1–3 months (usually Broca's), then it resolves into a residual anomic aphasia. Studies show that spontaneous improvement, if it happens, occurs within six months, but complete recovery is rare. Persons with global aphasia are usually mute or use repetitive vocalization. The person frequently uses simple words such as expletives. 4. Disconnection syndrome: This is due to a small lacunar infarct in the arcuate fasciculus – the main problem with the disconnection syndrome is repetition. This syndrome is very rare! 5. Transcortical aphasia: Opposite to disconnection syndrome, this patient can ONLY repeat what you say. Has difficulty expressing himself either verbally or in writing. This is due to an infarct in the watershed area (usually due to sudden hypotension) between Broca and the association area. It is usually more sensory or more motor (more towards Wernicke or more towards Broca) The transcortical sensory won’t understand what you’re trying to say, but will be able to repeat words, whereas transcortical motor can understand bit. 6. Aphumia: The patient cannot talk, but CAN write – this can easily be confused with hysteria – this is when there is a small lacunar infarct just beyond Broca’s (between Broca and speech area) – the writing area not affected – dus can get words, but cannot get them out – but can write them.
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Must differentiate between aphasia (speech problems of central origin) and dysarthria (difficulty in pronunciation due to local problems) EVALUATION OF APHASIA:
1. Listen to spontaneous speech (Broca’s non-fluent, circumlocution, short sentences, neologisms, paraphrasing, Wernicke fluent but nonsense content)
2. Check comprehension – start with 1 step command, increase up to 4 stepcommand, such as close your eyes, close eyes and lift left hand, close eyes, lift left hand and touch nose, close eyes, lift left hand, touch nose, lift right hand. The more complex, and the more peripheral the more difficult to do. Broca will be able to do 3 step command (comprehension intact) Wernickes cannot do at all Global aphasia – can do one step
3. Naming objects to confirm diagnosis: what is this? What do we use it for? main problem with Broca is to find the word – they don’t know what you call a pen or a cup, but they know what you use it for – they may make a new word, or paraphrase, or describe, or just demonstrate Wernicke will not understand the instruction to name the object
4. Repeat a sentence: this test the arcuate fasciculus Must be relatively difficult long sentence i.e. the fat cat catches the thin mouse – if the arcuate fasciculus is involved the sentence will be short such as ‘cat catches mouse’ (still a bit right) – in Wernicke’s won’t be able to repeat at all. Broca will also have difficulty repeating, because the arcuate is usually involved – very seldom pure Broca.
5. Reading and writing: will be affected in the same way that spontaneous speech is affected – in Broca’s there will be neologisms and short sentences, wrong spelling, with Wernicke’s it will be meaningless. How to differentiate Wernicke’s from wordsalad due to psychotic process – the patient with Wernicke’s aphasia keeps to etiquette – he’ll wait for you to finish, then he’ll speak, then wait for you again. DR KAKAZA – TUTORIAL ABOUT HEMISPHERES 8/2/2011 Functions of lobes: 3) Parietal lobe If affected on any side, will get problems with 2-point discrimination and stereognosis, and depending on the side you’ll either have speech problems and Gerstman syndrome (Left hemisphere) or agnosia and apraxia (right hemisphere) Two-point discrimination is the ability to feel two stimuli at the same time. Patients with parietal lobe lesions can only feel one stimuli at a time, i.e. if they have L hemiparesis, and you touch them one the left hand side, they may be able to detect one stimulus on that
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side, but not two. If you then touch right hand side simultaneously as Left, they will not be able to feel the left hand sided stimulus anymore. Stereognosis is the ability to identify something by touch, without visual help. Lesion in either parietal lobe will give astereognosis. THE LEFT HEMISPHERE Parietal lobe Think SPEECH problems, GERSTMAN syndrome and DEPRESSION When the Left hemisphere is affected the patients get VERY DEPRESSED The left hemisphere does all the language, calculations and finger naming (reading, writing, rythmatic) If left parietal lobe is affected, you get Gertsman syndrome Gertsman syndrome:
1. Finger agnosia: the patient is disconnected from his fingers – he can’t name them when he folds hands together (church without steeple hands) – won’t be able to tell where his pinky is, or any of the other fingers. Remember the
typist who got to work and realised she couldn’t type
anymore without actually looking at her fingers – when she didn’t look, her fingers were not ‘there’.
2. Aculculia: inability to makes sense of numbers, loses even very simple maths – remember the accountant who had MVA and sustained swelling of the left hemisphere – he could not even do 1+1
3. Left/Right disorientation: cannot do evun simphe L/R comoands, e6en when they thin{ about it (touch your R ear with your L hand) If txey have all 3 Together (can’t recognise fingers, nqmbers or left/right) it is called Gertsman syndrome. It means Left Parietal Lobe dxsfunction, and it implkes a big46lesion. The patient wi|l also have visual field defect (R hemi-anopia9 (telporal vision of right eye and medial vision of left eye affectEd). RIGHT HEMISRHERE: The vight hemisphere is for a2t and emotion. The hemisphere of the psychiatrisp(– apraxia anä agnosma is consequelce of p2oblems here – neurologists don’t really worry about apraxia and agnosia. AprAxia is the inability to perform an action that they knew how To perform before, not attRibutable to any motor `roblem such as weakness – can do individual tasks, but cannot put them together. Dressing apraxia is easily picked up – give them a shiru – they won’t know how to put it on, they may try and faml completely, or just havg difficulty buttoning the shirt. One of the
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main reasons for the severe disability of dementia patients is due to apraxia – need total care. Agnosia: this is when you neglect something, when you cannot recognise something – from very abstract such as inability to recognise humor, to concrete, such as inability to recognise familiar objects. Anosagnosia is the common type – when the patient has hemi-neglect A patient with a infarct in Right hemisphere will neglect his left side. This will be noticeable in that if you stand on his left hand side he will seemingly be ignoring you, When you walk to the right hand side he’ll respond. The patient may even look away from the left side, as if it is ‘not there’. Because of agnosia they tend NOT to be depressed, because they don’t recognise that there is a problem The patient will always have a hemi-anopia – always check visual fields. (can’t see the left temporal field – also ‘agnosia’ to the left) 2. Prosopagnosia: another common type of agnosia This is the inability to recognise familiar faces, can only recognise a person by voice and other characteristics, but not by face. FRONTAL LOBE: Personality and executive function is in the frontal lobe: Orbito-frontal syndrome – disinhibition, environmental dependency, poor short term memory, inability to sustain attention, inappropriate social behaviour, including sexual disinhibition, easily distractible, mood lability, no insight) Dorso-lateral dysfunction – especially executive dysfunction, the patient cannot plan, organise, execute substeps with final goal in mind. Anterior cingulate – patient is typically apathetic – has motor apathy, emotional apathy and cognitive apathy These syndromes are only found when there is bilateral dysfunction - such as with degenerative processes or multi-infarct dementia – seldom with one stroke, unless the patient only had one stem of the ACA and the stroke/thrombus is in the stem. Gait apraxia due to frontal lobe problems – also when there is extensive damage. The pt will walk tentatively, with small steps, as if ‘on ice’, as if the feet is stuck to the floor – later complete inability to move, but when you put him in bed, can make walking movements on request. When you see gait apraxia in an elderly patient, think of NPH, parafalx meningioma or butterfly glioma, parkinsonsism due to drugs, or end stage PD. Cranial nerve fall-out in a cortical stroke – II, V, VII do not have bilateral supply – look for fall-out with them.
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Patient will have hemi-anopia (II), reduced sensation of face (V), weak lower half of face (UMN VII) – this will all be on the same side as the weak side, and contralateral side to lesion. A small percentage of patients also have unilateral supply for IX, X – may have soft palate weakness. If you get stroke too early may especially have more CN deficits (such as IX, X, XII) because bilateral supply takes some time to take over) DR KAKAZA TUTORIAL: 15/2/20100 CONTINUE WITH STROKE PATIENT: Reflexes: deep tendon reflexes are graded from 0-4, remember to augment (actually only distracts the patient..) 0:
this is a hard LMN sign, can find it in a GBS that is still walking
1:
flicker felt or seen in muscle (remember to expose muscle)
2:
muscle contracts and some movement around joint is seen
3:
muscle contracts, brisk joint movement that spreads to other joints (biceps reflex
and fingers flex, or knee reflex and adductor of other leg contracts 4:
hard UMN sign that implies clonus. This is never normal. Must get at least 5 jerks
(not 3). We only elicit it in the foot and patella Almost all normal people have a 2, but 1 and 3 can also be normal depending on the setting (someone with NO neuro sx, weakness or other UMN signs with a 3 is considered to be normal, whereas is MND, where there is severe atrophy a 2 is considered to be UNN. Asymmetry also important – if 1 on one side and 2 on other think previous stroke) Babinski is a hard UMN sign (primitive reflex) – the mildest form may just be flaring of the toes, the worst form is withdrawal flexor respons. Also do Oppenheim and Shadock to confirm. A mute response usually means the patient is in shock. Hoffman and finger flexion test: not a strong UMN sign but is suggestive. Patients with a ‘normal’ 3 may have a Hoffman, but it becomes significant when it is associated with weakness, if it is asymmetrical or if there are other UMN signs. Crossed adductor reflex: seen in UMN lesions. Hit on adductor of knee medial and look at other leg – often see it in paraplegic patient Abdominal reflex: these are the only reflexes absent in UMN disease. Not relevant if someone was previously pregnant, previous surgery or obesity. SENSATION: Spinothalamic (ST): pain, temperature and crude touch (fine fibres) Dorsal columns (DC): position, vibration and fine touch (thick fibres) Parietal lobe sensation: 2 point discrimination and stereognosia.
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You must check all sensory tracts, because ST runs anterior in cord and crosses immediately whereas the DC runs posterior and cross in the medulla. Always look for a pattern in sensory loss: Neuropathy: glove and stocking Myelopathy: level Brain stem: checkerboard Cerebral hemispheres: hemi Dermatome loss with radiculopathy Vit B 12 deficiency and HIV both gives you myelopathy with UMN, but also neuropathy with glove and stocking. Cerebellum: Dont’ forget the gait! If they can do tandem walking – co-ordination normal Toe heel walking – strong distally Squat and stand up – strong proximally Lift up arms above head – strong proximally Hold your fingers – strong distally MARSDEN TEST: Tap index finger quickly on proximal joint of thumb. If the tapping is clumsy or slow, think: 1. Weak 2. Spastic 3. Rigid 4. Apraxia (always give leeway for non-dominant hand) Barre test: hold both arms out, patient closes eyes and counts backwards – weak arm will drop, pinky will extend and arm will pronate. THE OFF-BALANCE PATIENT: 1) EPISODIC OR CONTINUOUS? If EPISODIC think EAR: The ear consists of the hearing part (cochlear) and balance part (vestibular). The vestibular part consist of semi-circular canals with endolymph, hairy cells and otoliths.
a) Acute viral vestibulitis: a few days of acute vertigo Page 49 of 61
b) Episodic positional vertigo: suddenly he becomes dizzy, but if he keeps the head then still, the dizziness will go away – this is because one of the otoliths move from its normal position and disturb the haircells. When you stand still the endolymph stops moving, and therefor the otolith and haircell stops moving – vertigo goes away. Make diagnoses with the Hall Pike manoeuvre: lower the patient down over the bed so that head is lower than the bed, turn the head to the side and see nystagmus. This can also be the treatment (move head several times from side to side whilst head is low) or give symptomatic treatment (cinnarizine; (Stugeron) or beta-histine; (Serc))
c) Meniere’s disease: this is a degenerative and disabling condition. The patient has constant vertigo, progressive hearing loss and a constant ringing in the ears. Treatment is to hasten the destruction of the nerve by injecting gentamicin. COCHLEAR COMPONENT OF VIII: Its job is to hear sounds. The sound goes via the nerve to Hershl’s gyri (receptive area for hearing). If one ear is deaf – must be local problem If both ears are deaf – probably still local problem This is because if one of the Hershl’s areas (superior temporal gyrus) is disturbed, it will not amount to hearing loss. If the problem is bilateral (strategic strokes or rarely syphilis) the patient will still hear sound, although can’t differentiate words (can still hear animal sounds, something being dropped, telephone, sometimes music) because these sounds are interpreted somewhere else. Hershl decodes the sound into words, so some sounds can still be heard, but patient has an agnosia for words. This is often associated with aphasia because Hershl’s gyri is close to the language/speech centres. NON-EPISODIC ‘OFF-BALANCE’ (ALWAYS FALLING) This is either sensory ataxia or cerebellar ataxia or brainstem pathology that catches the cerebellar pathway. SENSORY ATAXIA: This is usually in the setting of a peripheral neuropathy, when the dorsal columns for propioception are destroyed. The propioceptors tell us where our feet are, and make us look down when the ground becomes uneven. This patient may also complain of distal weakness, pain, and the feeling of ‘having a tight shoe on’, or that the ‘feet are wrapped in cotton wool’. The patient won’t be able to walk at night, because they rely on their eyes not to fall.
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Sensory ataxia has a broad based gait, with the patient looking down to see where they are walking. The most common causes include B12 deficiency (postero-lateral cord syndrome), HIV and GBS. If the sensory ataxia is very severe the patient may be totally unable to walk, although he has near normal power, and can make walking movements in bed (this is called abulia, and is also seen in the gait apraxia of dementia.) Central vertigo can also be due to MS plague, brainstem problem or cerebellar problem. If in the cerebellum, expect only cerebellar signs, if in the brain stem will have CN fallout and longtract signs. Dws, if ATAXIA PLUS something else - not pure cerebellar problem. Alcohol attacks the vermis and flocculonodular lobe of the cerebellum with gait and truncal ataxia – this is due to nutritional causes as well as direct toxic effects of the OH.
DR KAKAZA TUTORIAL 18/2/2011: SPINAL CORD: Symptoms suggestive of spinal cord pathology includes
1) Weakness – either both lower limbs, or all 4 limbs (paraparesis or quadriparesis) 2) Sensory level – patient may complain of tightness, a ‘tight belt 3) Urinary symptoms – may be presenting symptom, in which case it will be urinary retention (bladder distends and sphincter remains closed), or, if it is a chronic, slow onset lesion the problem may be frequency and urgency – more noticeable at night. This is because of bladder spasticity, and reduced capacity – does not expand anymore. If the lesion is in the cauda equine it is bad news – the urine dribbles the whole time, and patient will need a catheter the whole time (not intermittend catheterization as in the others) Anal sphincter symptoms will present with constipation and distended abdomen.
4) Back pain may also be complaint: if the pathology is due to vertebral collapse the patient will feel exquisite, and very localised pain (they’ll ask you to turn around and point to your back). If the vertebral collapse also involve a root it will cause a radicular pain (neuralgic). The back ache may also be a pure mechanical pain due to their struggling to walk.
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With a chronic lesion the patient may complain that their leg often ‘kicks’ or flex on its own – points to UMN pathology Thus, when you hear the pattern of weakness, sensory fallout and bladder problems, think MYELOPATHY ON EXAMINATION: Confirm the motor weakness, usually UMN with spasticity, Babinski and crossed adductors. Get level and remember Beevor sign. But sometimes you’ll find LMN signs – this could be due to: 1) Shock phase in hyper acute lesion
2) Arachnoiditis (inflammation of the roots will mask UMN signs) 3) MND: truly mixed UMN and LMN, for instance wasted leg with increased reflexes. 4) Cord lesions involving ONLY the anterior horn cells (polio)
5) ADEM: extensive lesions catching the anterior horn cells (ant horn cells serves same purpose as the CN nuclei – LMN) 6) Syrinx 7) Myelopathy with superimposed radiculopathy (CMV) 8) Myelopathy plus neuropathy (HIV, B12 deficiency, HTLV-1) 9) Cervical spondilosis The patient may also have BOTH UMN and LMN signs: LMN at the level of the lesion UMN: below the level of the lesion If you find the LMN signs you can localise the lesion to that level, for instance if biceps reflex is gone, you know level is C5, 6 or if you see atrophy of the interossei, you know level is C8, T1. Sensory examination: The patient will have a level in a myelopathy, or sometimes a suspended sensory level (can feel above and below level) – that is due to central cord lesion. You MUST turn over the patient to check the sacrum and perineum – check for sacral sparing which you’ll get with central cord lesion (sacral fibres at the very outside). You can also have sensation loss ONLY over the perineum (saddle anaesthesia) which you get with cauda equine and conus medullaris lesions. Remember to check the anal sphincter tone in the exam – can help you localise lesion –(S2-4)
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Remember to inspect and palpate the back, run hand down back to find gibbus, and hit lightly for any areas of tenderness. Must examine spinothalamic and dorsal columns separately. Spinothalamic: pain, temp and crude touch (finger) Dorsal columns: vibration, propioception, fine touch (cotton wool) The lesion is usually 2 segments higher than the sensory level (T10 level – lesion on T8), whereas the motor level will have the same lesion level; but lesions in the cord usually not uniform, and motor and sensory lesions often don’t tally – take the highest level for localisation. Co-ordination difficult to test due to weakness, but if a patient can walk it will be spastic gait with scissoring (as opposed to the broad based gait you get with cerebellar and sensory ataxia) AFTER YOU’VE DIAGNOSED MYELOPATHY:
1) DO MRI: this will differentiate between compressive and non-compressive lesions. A compressive lesion needs immediate surgery (could be cold abscess due to TB, or pyogenic abscess due to strep, or metastatis or primary tumor). Anyone who still has sphincter function of a deficit with history of less than 48 hours – needs immediate surgery (bladder will not recover if left longer than this) 2) If it is not a compressive lesion the causes are considered to be medical, such as
A. Infections: TB number one (gives both compressive and non-compressive) Bilharzia, think especially of this if the lower lumbar area is affected HIV Toxoplasmosis, cysticercosis, syphilis, HSV, VSV Transverse myelitis: viral or post-viral cause, dx on MRI – the whole cord will light up, but ALSO be swollen (no swelling in MS) B. Demyelinating lesions: MS gives localised demyelination Neuromyelitis optica and ADEM longer lesions Dx on MRI C. Vitamin B12 deficiency D. Vasculitis or occlusion of a vessel d/t emboli
E. Neoplasmas: if it is inside the cord they are non-compressive, can be primary or secondary
F. Paraneoplastic syndrome: an antibody mediated condition where Ab against the Ca cross reacts with protein in the cord – death within few days.
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MYELOPATHIES can also be discussed according to ANATOMICAL LOCATIONS (CORD SYNDROMES:
1. Transverse myelitis: the whole cord is affected on horizontal level, but still patchy (motor and sensory may not be the same) Motor: all below lesion will be affected, at the level of the lesion there will be LMN signs, and UMN below lesion Sensory: ST and DC will be affected 2. Anterior spinal artery occlusion: The anterior artery supplies more than half of the cord, and both hemispheres. Occlusion has a sudden onset, ST level, motor level, but DC intact. Atherosclerosis of the aorta is the most common cause, or AI disease in young people (SLE) 3. Syrinx: This is usually at C5. An early lesion may just disrupt DC crossing with a suspended level or neuralgic pain in shoulder. When the lesion expands it catches the anterior horn cells, and there will be atrophy at the level of the lesion (C8, T1) with pain and atrophy in the hand. The progression of a syrinx usually stops here. If the lesion still expands it will start catching tracts, and a proper sensory level will develop, but a strange level, this is because sensory fibres are laminated, with sacral fibres being on the very outside, and cervical on the very inside (med to lateral: Cx, T, L, Sacral) On the differential would be a syrinx, tumor, granuloma and plague. 4. Hemisection of the cord (Brown Sequard) Ipsilateral to the lesion weakness and DC fallout, contra-lateral to lesion will be ST fallout. Causes: anything lateral – could be tumor, trauma (gang-knife violence!), VSV that tracts back into cord from the usually radiculopathy. 5. Posterolateral column syndromes: This is usually due to a destructive process, where the DC are affected and the patient has spasticity (CS affected) but no ST level. The patient can usually still walk despite extensive weakness because the spasticity keeps them upright. Vit B12 and HIV the common culprits 6. Lateral cord syndromes:
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Mainly destruction of CS with spasticity as main complaint, caused by HTLV-1, or sometimes hereditary spastic paraparesis or Cassava toxicity. HTLV-1 treated with solumedrol THE PATIENT WITH MYELOPATHY AND COGNITIVE DECLINE:
1. Vit B12 deficiency: patient with cognitive decline, paraparesis, spasticity AND neuropathy and rarely optic neuritis. Check the psych manifestations of Vit B12 deficiency (usually paranoid)
2. HIV: usually late stage, with CD4 less than 200, often less than 50. The patient will have a paraparesis caused by vacuoles in the postero-lateral columns (called vacuolar myelopathy). At this stage the patient will also have a superimposed, painful neuropathy, due to the virus itself. 3. Leucodystrophia: (Adrenomyeloneuropathy) This is an inherited disease with a sudden loss of the ability to myelinate, PLUS involvement of the peripheral nerves and adrenals (overweight white boy with hypogonadism and myelopathy, cognitive decline and neuropathy.
4. Syphilis: mainly the dorsal columns affected with sensory ataxia and high steppage gait and cognitive decline. Remember: Cortical stroke: DC, ST affected same side as motor Brainstem stroke: if lateral stroke will have sensory fallout with motor spared, if medial stroke will have motor fallout but no sensory (bleed in brainstem may be much wider) Spinal cord stroke: will get dissociation between ST and DC DR KAKAZA: 21/2/20100 RADIOLOGY Compare
the
4th
to
the
lateral
ventricles
to
decide
between
communicating or obstructive hydrocephalus. The prepontine cistern should also be open
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BITS AND PIECES: Viral causes of meningitis: Any childhood viral illness, such as MMR, enterovirus, ricketsia and enterovirus Immunosuppressed patient HSV, VSV, CMV, PML Contra-indications to LP: Localising signs (may see false localising signs with raised ICP, or cranial nerve palsy due to exudates, or with infarction or thrombosis Seizures (sign of focal pathology) Local sepsis Bleeding tendencies (platelets 30 y, unilateral First symptoms is VIII compression (deaf and tinnitus), then V and VII sensory fallout. VII motor fallout happens last because the motor fibres are more resilient than the sensory fibres. If the hearing loss is neurological (as in this case) the Weber test will localise to the unaffected side Radiology: MRI – T1 – anatomy, fluid dark T2 – fluid bright Diffusion weighted MRI – diffusion is ‘random molecular motion’, designed to detect random movement of H2O. White matter pathology on MRI: White matter hyperdensities divided into 2 groups, namely 1) demyelinating (myelin destroyed) or 2) dysmyelinating (does not form) Hyperintensities can be diffuse, focal or geographic Focal problems – must differentiate MS from deep white matter ischemia and normal aging (leukoariosis) PML – can make diagnoses on MRI – the peripheral white matter is involved. Trauma: shearing occurs at the gray/white matter junction HIV encephalitis: gives diffuse white matter changes Central pontine myelinolysis: geographic white matter lesions, may look like upside down bat on MRI. Wernickes’: mammilary bodies affected – can see on MRI
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HSV: affects the limbic system (internal temporal lobe, hippocampus and cingulated gyrus) bilaterally. Acute hydrocephalus: will get capping of the ventricals. Anti-psychotics give beta-waves NPH presents with gait apraxia, urinary incontinence, and dementia – clinical diagnosis, may have mildly dilated ventricles on scan, but if you do an LP the pressure is normal – patient clinically improved after LP. IDIOPATHIC INTRA-CRANIAL HYPERTENSION: Diagnosis by exclusion. Blurry vision due to CN VI palsy (when a patient looks to the side you must not be able to see the lateral sclera) Headache, early morning, worse when coughing, patient may vomit (intracranial pressure is highest at about 2am) Pappil edema with disk swelling but normal visual acuity Causes of papiledema with normal scan: Chronic meningitis Demyelinating illness (usually unilateral edema) Papillitis (also usually unilateral) Venous sinus thrombosis Differentiation between papillitis and papiledema: With papillitis the patient is blind, whereas with papiledema vision is initially intact Papillitis is painful, whereas papil edema is asymptomatic. Parasomnias: Patients have bizarre behaviour during sleep, what they would not normally do. It often precedes neurodegenerative illness. Guillian Barre syndrome: Why increased protein in the CSF? Because the spinal roots may also be demyelinated, protein leaks from the axons in to the CSF Neuropathic
pain:
Tegretol
not
recommended
treatment,
rather
amytriptiline
or
gabapentin
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Thalamus: a 3x1.5 cm structure between the lateral wall of the 3rd ventricle and the internal capsule. It is not a uniform cellular complex – rather a collection of >100 nuclei. You should not see vessels in a pre-contrast CT, but with old age and atherosclerosis you may see it due to calcification How do we test for pituitary function? Prolactin, growth hormone, TSH, LH, FSH, testosterone The most important consequence of pituitary hypofunction is Addison’s syndrome Syndrome of inappropriate ADH (SIADH) caused by Meningitis Stroke Convulsions Tegretol and Lithium Absent ankle reflex: may be just old age (>60y) or due to peripheral neuropathy such as DM, alcohol, drugs, HIV Synkinesia: a simultaneous movement that should not be there, such as the mouth lifting when the eye blinks. It is usually due to aberrant innervation, usually after a Bell’s palsy. Abnormal
movements:
dystonias,
choreo-athetosis,
hemi-ballismus,
tremors,
myoclonus, tics, mannerisms, focal dystonia, tardive dyskinesia and more! Tics are more somewhat suppressible and will reduce when patient is distracted, whereas TD will worsen on distraction. The movement of the tic reduces tension of the premonitory urge. Nerve conduction: it tests the electrical impulse between 2 points. It ONLY picks up peripheral nerve damage, and not even all of that (will miss small fibre neuropathy) Types of tremors: postural, intentional, and resting Neurocutaneous syndromes: 1. Neurofibromatosis 2. Sturge Weber syndrome 3. Tuberous sclerosis They all have mental retardation, brain tumors and skin manifestations. Paraneoplastic syndromes: this is non-metastatic manifestation of malignancy, immune mediated. MG (thymoma) and dermatomyositis (breast and gyne Ca) Episodic neurological disorder:
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Headache and epilepsy the most common, also paroxysmal movement disorders, hallucinations, sleep disorders, anxiety attacks, motor tics Stress and fatigue may precipitate, and diet and drugs may affect it Usually develops in infancy, worsens over the years, and starts to get better in mid-late adult life. Voltage dependant channels (K, Na, Ca) play a role Episodic disorders with abnormal movements: Primary episodic ataxia (6 types) Attacks of imbalance and in-coordination due to gene mutations leading to disruption of K and Ca channels. The cerebellum and motor neurons have highest concentration of these channels, therefore the specific symptoms. Diagnose with EMG Triggered by stress Paroxysmal dyskinesia: Brief attacks of unilateral dystonia and choreo-athetosis without disturbance of consciousness. It may be idiopathic, familial, or due to trauma or MS. Malignant hyperthermia also voltage gated channelopathy Periodic paralysis: usually in association with K, sometimes too much, sometimes too little – can present just like conversion disorder!
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