Neurology IM Flashcards
Definition of epilepsy?
Chronic neurologic disorder with predisposition to seizures and defined by one of:
1. Two or more unprovoked or reflex seizures separated by over 24 hrs
2. One unprovoked or reflex seizure in individual with high risk of subsequent seizures
3. Diagnosis of an epilepsy syndrome
Causes of central vertigo?
Main concern is Posterior Circulation Stroke.
Causes of peripheral vertigo?
Benign Paroxysmal Positional Vertigo (main)
Vestibular Neuritis (main)
Ramsay-Hunt Syndrome
Drugs (Gentamicin, cisplastin)
Labyrinthine trauma
How to differentiate Central vs Peripheral vertigo with an exam?
HINTS EXAM!!!
Central = all 3 components reassuring
Peripheral = Any 1 component worrying
Head Impulse, Nystagmus and Test of Skew (HINTS)
Central vs Peripheral vertigo clinically?
Vertigo lasts hours in Stroke Central Vertigo, but shorter durations do not rule out TIA.
Central = not a/w head movement.
Peripheral = a/w head movement.
Central = Neurological deficit
Peripheral = No neurological deficit
What is miller fisher syndrome?
Rare variant of GBS.
Triad of ataxia, areflexia, ophthalmoplegia
Causes bilateral eye and muscle weakness + cerebellar gait issues.
Start in legs, slowly spread to arms and face
Presence of Ab to GQ1b in 90%
What is inverted supinator reflex? Associated with?
When supinator reflex elicits finger flexion instead of elbow flexion.
Indicates lesion at C5 or C6
Causes of peripheral neuropathies?
Diabetes
B12 deficiency
Guillaine-Barre
Iatrogenic
Types of mononeuropathies?
Median neuropathy (CTS)
Ulnar nerve palsy
Radial nerve palsy
Common peroneal palsy
Facial palsy
3rd CN palsy
Lateral femoral cutaneous palsy
Lateral femoral cutaneous nerve palsy also known as meralgia paraesthetica
What is Chronic Inflammatory Demyelinating Polyneuropathy?
Progress of symptoms beyond 6 wks or relapsing-remitting in nature
Often has generalized hyporeflexia and symmetrical, proximal and distal pattern of weakness and some distal sensory involvement
Types of Multiple Mononeuropathies?
Vasculitic neuropathies
Multiple entrapments
Amyloid
Sarcoidosis
Lyme disease
Lymphomatous or carcinomatous infiltration
How does vasculitis neuropathy present?
Classical acute/subacute onset of mononeuritis multiplex
Distal sensorimotor axonal peripheral neuropathy
Radicular / plexus pattern
Mononeuritis multiplex happens when there is damage to at least 2 different areas of PNS. Causes tingling, numbnes, pain, paralysis etc.
What is mononeuritis multiplex?
when there is damage to at least 2 different areas of PNS.
Causes tingling, numbnes, pain, paralysis etc.
Clinical features of Myasthenia Gravis?
Flucutating weakness, abnormal fatigue that improves with rest
Weakness can affect extraocular, bulbar or proximal limb muscles
Ocular = asymmetrical ptosis, extraocular eye movement limitation
Bulbar weakness = difficulty swallowing, chewing, speaking
Limb weakness = usu symmetrical and proximal
Can cause neck weakness or head drop
MG crisis = respi muscle weeakness causing ventilatory failure
Deep tendon reflexes usu preserved
4 subtypes of stroke?
Cryptogenic 40%
Large artery atherosclerosis 15-40%
Small vessel occlusion/Lacunae 15-30%
Cardioembolic 15-30%
Why cant u give heparin/warfarin after stroke?
BBB is compromised right after stroke. So blood can enter brain after stroke (haemorrhage), killing them
Research showed LWMH raises risk of ICH
Which spinal tracts can hypothalamic infarct affect?
DCML and corticospinal tract decussates NEAR the thalamus.
Hence can have hemiparesis in some parts.
Management of postural hypotension after excluding all causes (even ANS)?
Give Fluorocortisone + Midodrine. Fluorocortisone is a mineralocorticoid with water-retention effect. Hence watch out for metabolic alkalosis and supine HTN. Midodrine is an alpha-adrenergic agonist, causing vasoconstriction.
For non-pharm mx, give abdominal binder, compression stockings, avoid hot showers, avoid big meals. These are all things that can cause peripheral vasoconstriction.
Does body try to recruit collaterals in stroke?
Body often tries to recruit collaterals in stroke, but when this fails then deficits result.
But thats why after a while the stroke can improve cuz collaterals can be recruited.
How does Atrial Fibrillation form clots?
Chaotic contraction. Not all the blood moves out of L heart, with stagnated blood left. This blood just stays there and stagnant. This blood can form clots in ppl with prediposing factors e.g. DM, age, structural disease. Lack of clearance causes blood stasis and clot formation. Left atrial appendage stores all the clots.
Timing for EVT and TPA?
EVT can be done up to 6.5 - 10 hours.
TPA within 4.5hrs
What is pulse deficit, and what is it a characteristic of?
Difference btw pulse rate measured by cardiac auscultation and peripheral pulse rate obtained by palpation. Can hear heartbeat on auscultation, but cannot feel.
Characteristic of AFib!!!
How can motor homunculus help classify stroke location?
It can help classify cortical stroke areas by affected body parts
Causes of delayed pulse?
Dissection. What else?
How to know the lesion type by onset duration?
Slowly progressive onset = slowly growing expansile lesion
With occlusion, onset is always acute
2 determinants of clot formation in heart that can be seen on TTE?
- size of LA (LA diameter) = atrial cardiopathy
- REgional wall motion abnormality = some form of infarction of cardiac tissue causing that area to not move so well - causing dyskinesia of cardiac muscles, causing blood stasis and hence clots.
Hence all conditions that cause blood stasis in heart predisposes to clot formation.
Valvular defects is a diff issue. Its just either too narrow or too lax. But only L heart valvular issues predispose to clot formation, and especially raises risk of clot leaving the heart.
Investigations for stroke?
CT scan!! = can do perfusion scan to check for penumbra. Can also inject dye to check arteriogram.
MRI!!
What kind of muscles does UMN lesion usually cause?
Usually weakness in antigravity muscles
How long for ICP to rise post-stroke?
2-5 days for bigger strokes.
Within 24hr for small strokes
Stroke mimics?
Seizures, Migraine, fainting
Functional Neurological disorder
Test for BPPV??
Dix-hallpike maneuver to diagnose.
Epley maneuver to treat.
What is VBI?
Transient fall in bloodflow in posterior circulation of brain.
Symptoms include vertigo, syncope, nausea, visual/auditory disturbances, dysphagia, hemiparesis.
Etiologies include atherosclerosis, hypotension, cervical bone compressing vertebral arteries.
Reclining or rotating head can trigger symptoms
What is Meniere disease?
also known as
Disorder of inner ear caused by impaired endolymph resorption.
Meniere triad of peripheral vertigo, fluctuating unilateral sensorineural hearing loss, unilateral tinnitus.
What is vestibular neuritis
Inflammation of vestibular nerve with features of vestibular dysfunction.
E.g. vertigo, N/V, gait instability. Usually no hearing loss.
Idiopathic Parkinson’s usually presents in what manner?
Asymmetrical pattern
UMN + LMN signs point to what kind of diseases?
Points to motor neuron disease e.g. ALS
Amyotrophic lateral sclerosis
What is myasthenia gravis associated with? How to diagnose?
Thymoma.
Anti-Ach receptor Ab OR single-fiber EMG can help diagnose MG.
What drugs for refractory seizures? what about acute seizures?
Keppra or Phenytoin for refractory.
Benzos for acute seizures
Characteristics of atypical Parkinsonism?
Refractory to drugs and has rapid onset.
What is essential tremor?
Neuro condition that causes involuntary and rhythmic shaking.
It is AD inherited.
Improves with alcohol.
What is ataxia?
absence of voluntary muscle and coordination and loss of control of movement, affecting gait stability and movement.
Nerve Conduction Study’s features of demyelination?
Slow conduction with preserved amplitudes of action potentials.
NCS features of axonal degeneration?
Small amplitudes of action potentionals with preserved conduction velocities.
Huntington is a AD-inherited neurodegenerative disorder. What does it cause?
Chorea - involuntary irregular movements of limbs, neck, head, face.
Chorea can also point to ipsilateral cerebral cortex dysfunction.
What is vermis? What does a lesion here cause?
Unpaired medium portion of cerebellum connecting the 2 lobes.
Lesion here causes truncal ataxia - try to sit down but will fall to one side.
How to use NIHSS score?
NIH Stroke Scale
<5 = no stroke
5-15 = mild stroke
16-20 = moderate stroke
21 and above = severe stroke
What classification for stroke location?
Oxford stroke classification.
TACS
PACS
POCS
LACS
Criteria for TACS?
Total anterior circulation stroke
ALL 3 of following:
1. Unilateral weakness and/or sensory deficit of face, arm, leg
2. Homonymous hemianopia
3. Higher cerebral dysfunction
The hemiplegia and/or hemisensory deficit need not affect all 3 of F/A/L (because that would require a large cortical territory to be infarcted…)
Criteria for PACS?
Partial anterior circulation stroke
TWO of following:
1. Unilateral weakness and/or sensory deficit of face, arm, leg
2. Homonymous hemianopia
3. Higher cerebral dysfunction
Criteria for POCS?
Posterior circulation syndrome
ONE of following:
1. Cerebellar or brainstem syndromes
2. Loss of consciousness
3. Isolated homonymous hemianopia
Criteria for LACS?
Lacunar syndrome
ONE of following:
1. Unilateral weakness and/or sensory deficit of face and arm, arm and leg or all 3
2. Pure sensory stroke
3. Ataxic hemiparesis
Commonest cause of LACS?
90% due to small-vessel lipohyalinosis 2’ to chronic HTN
1-% due to microatheroma, embolism
Small-vessel lipohyalinosis is fibrinoid small-vessel degeneration
Presentation of ACA vs MCA infarct in Anterior Circulation Syndrome?
ACA = LL, Bladder, Genitals
MCA = UL, Face
Cortical signs to look out for?
Expressive/Motor aphasia = Broca’s in frontal lobe
Receptive aphasia = Wernicke’s in temporal lobe
Apraxia = Dominant parietal lobe
Hemineglect = Non-dominant parietal lobe
Contraindications to thrombolysis in stroke?
IV rTPA 0.9mg/kg infusion,. within 3-4.5 hours
Acute ICH/ Hx of ICH
Severe uncontrolled HTN
Serious head trauma/stroke in prev 3 months
Thrombocytopenia/Coagulopathy
If pt is currently taking LWMH, Apixaban/Rivaroxaban, Dabigatran/Argatroba
Severe hypoglycemia/hyperglycemia
Early radiographic ischemic changes
What to do within 24 hours if stroke pt has undergone thrombolysis?
Obtain Non-contrasted CT/MRI brain 24 hrs post-thrombolysis to ensure no haemorrhagic conversion, prior to initiating SAPT.
ABCD2 score for TIA?
Risk of stroke in TIA
Age >60
Blood pressure >140/90
Clinical feature (1 if speech disturb wo weakness, 2 if unilateral weakness)
Duration (1 point = 10-59 mins, 2 pts >1hr)
Diabetes
0-3 = Low risk
4-5 = Moderate risk
6-7 = High risk
Cortex vs Subcortical lesion effects??
Cortex causes higher cognitive function loss
Subcortical lesions cause pure motor or sensory syndrome.
Diagnostic for Temporal Arteritis?
Duplex US of temporal artery 1st line.
1. Edema + thickening of vessel wall (halo sign).
2. Compression sign can also be seen.
Temporal artery biopsy is GS.
Treat with Prednisolone
How to use GCS?
> 13 is ok
<9 is bad
<8 is coma
What is Duchenne muscular dystrophy?
X-linked genetic disorder.
Causes progressive muscle degeneration and weakness.
Proximal weakness = watch for heart/respi muscles
Causes of Parkinsonism?
Wilson Disease
Neuroleptic medication
Infective encephalitis
Idiopathic
Symptoms of Guillain-Barre?
Ascending numbness + weakness
Areflexia
No wasting of muscles
Look out for Respi failure, arrhythmias
4 states of impaired consciousness?
- Lethargy
- Obtundation - respond to non-pain
- Stupor - respond to pain
- Coma
What abx for menginitis?
Ceftriaxone empirical for strep pneumo
Ampicillin for Listeria in elderly
What is syringomyelia? What can it cause?
Fluid-filled cyst within the spinal cord. It can damage spinal cord to cause dissociative sensory disturbance.
How to differentiate btw seizure and syncope?
Seizure has post-ictal period of confusion. May have defecated or urinated during seizure.
Seizure has no prodromal symptoms and may not recover spontaneously.
4 signs of chronic ischemic stroke on CT?
hypodensity (cytotoxic edema),
loss of gray-white differentiation,
cortical swelling
loss of sulcation (effacement of brain sulcus from tissue swelling).
Triad of normal pressure hydrocephalus?
Dementia
Gait disturbance
Urinary incontinence
