Neurology Flashcards
Cause of unilateral spatial neglect and dressing apraxia
Non-dominant inferior parietal lesion
- MCA infarct
DWI-FLAIR mismatch
Acute ischaemic lesion detect with DWI but not FLAIR - > within time window for thrombolysis
Lamotrigine toxicity
Sodium valproate
- Lamotrigine is extensively metabolised by N-glucoronidation
Sodum valproate inhibit its glucoronidation
Major concern of increased use of keppra
- Mood disorders e.g. suicidality
- Psychiatric disorder: aggression, abnormal behavior, suicide
Triad of meniere disease
- Episodic vertigo, sensisorineural hearing loss and tinnitus
- Dx only if episodic vertigo + sensorineural hearing loss
- Aural fullness + nausea might be seen
HINTS exam
Head impulse: 20 degree sudden rotation of head with eyes fixed on distance
- Normal: eye will rotate in the opposite direction
- Peripheral: abnormal - unable to maintain fixation
- Central - eye will rotate in opposite direction
Nystagmus (central: bidirectional; peripheral: unidirectional)
Skew deviation - cover and uncover eyes alternatively
- Peripheral: no deviation
- Central: vertical skew deviation (uncovered eye quickly shift from central to abnormal skew position)
Deep brain stimulation for PD
- Specific sites targeting
- Symptoms most likely improve on
Two specific sites target: subthalamic nucleus and internal segment of globus pallidus
Helps to improve
- Levodopa responsive symptoms, tremor, on-off fluctuations and dyskinesia
Stroke mimic > stroke
- Known cognitive impairment
- LOC or seizure at onset
- Migration of symptoms
- Positive symptoms: paraesthesia, jerks
Stroke > stroke mimic
- Exact time of onset
- Patient could recall exactly what they were doing at sx onset
- Well in the week
- Focal symptoms or signs
Management timing for acute stroke
Thrombolysis within 4.5h after onset
Thrombectomy: within 24h
Fridrich’s ataxia presentation
- limb ataxia
- Early loss of position and vibration (posterior column spinal cord dysfunction)
- Dorsal root and peripheral, primarily sensory, axonal neuropathy
- Affect autonomic -> bladder dysfunction
Rubrospinal tract
Red nucleus in midbrain -> decussate near point of origin and descend contralaterally in lateral funiculus of the cord
Rubrospinal tract
Red nucleus in midbrain -> decussate near point of origin and descend contralaterally in lateral funiculus of the cord
Transverse myelitis presentation
- Sensory, motor or autonomic dysfunction attributable to the spinal cord
- Bilateral
- Clearly defined sensory level
- No evidence of compressive cord lesion
- Inflammation defined by CSF pleocytosis or elevated IgG or gadolinium enhancement
- Progression to nadir 4h - 21 days
Ddx of optic neuritis
- MS
- Neuromyelitis optica
- Drugs ethambutol, alcohol
- Vit B12 def
- Ischaemic secondary to DM, temporal arteritis
- Familial e.g. Leber’s disease
- Infective: EBV
Features suggestive for MS
Suggestive
- Relapse and remissions
- Onset between 15-50
- Optic neuritis
- Lhermitte sign
- Internuclear ophthalmoplegia
- Fatigue
- Heat sensitivity (Uhthoff phenomenon)
Use for ocrelizumab
- Deplete CD20 expressing B cell
- For primary progressive MS
Complications of levodopa
- Motor fluctuations
- Involuntary movements (dyskinesia)
- Abnormal cramps
- Dystonia
- NOT Gait disturbances
Diagnosis criteria of essential tremor
- Bilateral action tremor of the hands and forearms (but not resting)
- Absence of other neuro signs, wth exception of cogwheel phenomenon
- Isolated head tremor with no signs of dystonia
Steroid use in bell’s palsy
Who has poor prognosis
- Severe complete paralysis
- Age > 60
- EMG: axonal degeneration
- Hyperacusis
- Altered taste
Association of PRES
- HTN (53%)
- Kidney disease (45%)
- Malignancy (32%)
- Dialysis dependency (21%)
- Transplantation (24%)
- AI disorders (11%)
- Eclampsia (11%)
Clinical presentation of PRES
- Seizure (85%)
- Headache (50%)
- Amaurosis/hemianopsia (blindness in nearly 50%)
- Altered mental status/coma (40%)
- N+V (30%)
- Transient motor defect (10%)
Triad of normal pressure hydrocephalus
- Gait impairment (specifically gait apraxia)
- Dementia
- Urinary incontinence
Treatment - Potentially reversible
- CSF drainage (VP shunt)
Wallenberg syndrome (Lateral medullary syndrome)
Occlusion of PICA
- Ipsilateral loss of facial pain and temp (trigeminal spinal nucleus and tract involvement)
- Contralateral loss of pain and temp (spinothalamic tract)
- Ipsilateral palatal, pharyngeal, vocal cord paralysis with dysphagia and dysarthria (nucleus ambigus)
- Ipsilateral horner syndrome (descending sympathetic fibres)
- Ipsilateral cerebellar syndrome
- Vertigo, N+V (vestibular nuclei)
- Hiccups (middle medulla)
- Diplopia (lower pons)
Foster Kennedy syndrome
Inferior frontal lobe tumor
- Optic atrophy in one eye
- Papilloedema of others
Gerstamann syndrome
- Agraphia, acalculia, finger agnosia, L right disorientation
Cluster vs migraine
- Cluster a/w unilateral phonophobia and photophobia
- Cluster: move around
- Migraine: motionless
CT head before LP
- Presence of papilledema
- History of recent head trauma
- Known or suspected intracranial lesion
- Focal neuro signs
- Depressed LOC
Features of EMG of MND
- Chronic partial denervation with preserved motor conduction velocity
Kennedy syndrome
- X-linked disorder
- Gynaecomastia and infertility
- LMN signs - progressive weakness in limb and bulbar muscle
- Male, mid-adult life
Treatment that prolong survival for MND
- NIV
- Riluzole only slow progression
- PEG only improves QoL
MOA of riluzole
- Na channel blocker that inhibits glutamate release
Conditions of purely UMN signs and purely LMN signs
Purely UMN - primary lateral sclerosis
Purely LMN - primary muscular atrophy
Drugs change level of carbamezapine
Increase
- Macrolides
- Isoniazid
- Chloramphenicol
- Ca blockers
Reduce
- Phenobarbitone
- Phenytoin
- Primidone
- St john wart
S/E of phenytoin
- Osteoporosis
- Ataxia, nystagmus
- Gingival hyperplasia
- Coarsening of facial features
- Loss of libido
- Hormone dysfunction
- BM hypoplasia
S/E of vigabatrin
- Drowsiness (most common)
- Neuropsychiatric symptoms
- Weight gain
- Visual field changes
AED that can weight gain
- Vigabatrin
- Pregablin
- Valproate
Features of posterior communicating aneurysm
- Painful 3rd nerve palsy
MOA of COMT inhibitors
- Tolcapone and entacapone
- Prolong and potentiate levodopa effect when given with levodopa
- Reduce the peripheral (entacapaone) and central (tolcapone) methylataion of levodopa and dopamine
Feature of 3rd nerve palsy
- Eye is deviate down and out
- Ptosis
- Pupil may be dilated
Weber syndrome - midbrain infarct
- Ipsilateral 3rd nerve palsy with contralateral hemiplegia
AED that affect OCP
- Enzyme inducer e.g. carbamazepine, phenytoin, phenobarbital
- SODIUM valproate does not affect
AED that most likely cause SJS
- Lamotrigine
AED to avoid in juvenile myoclonic epilepsy
- Carbamazepine
Important to uncover any hx of jerking, esp in the morning, before starting drugs
AED increase half life of lamotrigine
- Na valproate
Treatment of Essential tremor
- Propranolol
- Primidone
- Alprazolam
- Alcohol
Most common immediate symptoms of excess levodopa
- N+V
MOA of amantadine
- Enhance dopamine release
- Peripheral s/e: livedo reticularis, ankle oedema
- Other S/E: confusion, hallucination, nightmares
S/E of COMT Inhibitors
- Tolcapone: dyskinesia, hallucination, confusion, nausea, orthostatic hypotension
- Diarrhea, orange discoloration of urine, rarely hepatoxicity
- Lower the dose of levodopa either before or after addition of tolcapone
- Entacapone: not been a/w hepatoxicity
Pathologic gambling with PD
- Cuased by Pramipexole
- Dysregulation of dopaminergic tone
Clinical presentation of progressive supranuclear palsy
- Disturbance of gait -> fall
- Ophthalmoparesis or ophthalmoplegia (hallmark)
- Dysarthria, dysphagia, rigidity, frontal cognitive abnormalities, sleep disturbances
Poor response to levodopa
Upper trunk branchial plexopathy (C5, C6)
- Loss of shoulder movement and elbow flexion
- Sensory loss over lateral aspect of arm and forearm
Lower trunk brachial plexopathy (C8, T1)
- Claw hand
- Horner syndrome
- Sensory loss over (ulnar) side hand and forearm
Complete brachial plexopathy
- Horner
- LMN signs
- Sensory loss over whole limb
Foot drop
- Common peroneal nerve, L5, sciatic nerve
- If reflex intact -> common peroneal nerve or L5
Complete brachial plexopathy
- Horner
- LMN signs
- Sensory loss over whole limb
Femoral nerve
- usually seen in haemophilia patient with haematoma in iliacus muscle
- Weak knee extension (quadriceps), absent knee jerk, loss of sensory inner aspect of thigh and leg
Antibiotics reduce therapeutic effect of sodium valproate
- Carbapenum (meropenum, entapenum, imipenum)
S1 lesions
Sensory loss of posterolateral leg and lateral foot
Weakness in plantar flexion
Reduced ankle reflex
Positive sciatic nerve stretch test
L3 nerve root
Sensory loss over anterior high
Weak knee extension
Reduced patellar reflex
L4 nerve root
Sensory loss over the knee
Weak ankle dorsiflexion
Reduced patellar reflex
