Neuro Flashcards
Brown-Sequard Syndrome - pathophysiology and features
Hemi-cord lesion
Features
- Ipsilateralloss of proprioception and vibration
- Ipsilateral UMN weakness
- Contralateral loss of pain
Cerebellar signs
DANISH
Dysdiadokokinesia
Ataxia
Nystagmus (horizontal - ipsilateral hemisphere)
Intention tremor
Speech (slurred, staccato, scanning dysarthria- words are broken up into separate syllables)
Hypotonia
Causes of cerebellar syndrome
PASTRIES
Paraneoplastic (bronchial Ca) Alcohol (B12 and thiamine deficiency) Sclerosis Tumour Rare (Friedrich's, Alaxia Telangiectasia) Iatrogenic (Phenytoin) Endo (hypothyroidism) Stroke (vertebrobasilar)
Lateral Medullary syndrome
Alternate name, pathophysiology and features
Wallenberg’s syndrome
Patho: Occulusion of one vertebral artery
Features (DANVAH):
- Dysphagia
- Ataxia
- Nystagmus
- Vertigo
- Anaesthesia (ipsilateral facial numbness, contralateral pain loss)
- Horner’s syndrome
Beck’s syndrome
Cause, Pathophys, Features
Cause: aortic aneurysm dissection or repair
Pathophys: Infarction of the spinal cord in the distribution of the anterior spinal artery (ventral 2/3rd of the spinal cord)
Features:
- Para or quadriparesis
- Loss of pain and temperature
- Preserved touch and proprioception
Scissoring gait - area affected
Bilateral UMN lesion
Differentials of Parkinsonism
Parkinson’s disease
Multiple system atrophy
Lewy body dementia
Progressive supranuclear palsy
Vertigo causes
IMBALANCE
Infection/injury (labyrinthitis, Ramsay Hunt, trauma to petrous temporal bone) Meniere's disease BPPV Aminoglycosides Lymph Arterial (stroke/TIA, migraine) Nerve (acoustic neuroma/vestibular schwannoma) Central lesions (demyelination, tumour) Epilepsy (complex partial)
Commonest cause of unilateral sensorineural hearing loss
Acoustic neuroma
5 types of tremor
RAPID
Resting (Parkinsonism)
Action/Postural (Absent at rest, worse with outstretched hands or movement)
Intention (Cerebellar)
Dystonic (idiopathic)
Features of temporal arteritis
Unilateral temple/scalp pain and tenderness
Sudden blindness
Thickened, pulseless temporal artery
Associated with polymyalgia rheumatica in 50%
Migraine triggers
Chocolate Cheese OCP Caffeine Alcohol Anxiety Travel Exercise
Migraine treatment
Always give an anti-emetic (metoclopramide) as an adjunct
Mild-moderate:
1st - NSAID or aspirin
2nd - paracetamol
3rd - paracetamol+aspirin+caffeine
Severe:
1st - triptan+anti-emetic+NSAID
2nd - Ergot alkaloid (ergotamine)
3rd - corticosteroids
Causes of subarachnoid haemorrhage
Berry aneurysm rupture (80%) Arteriovenous malformations (15%)
First investigation of SAH
CT Head
If CT negative, do an LP >12 hours after start of headache
Drug given with SAH to reduce risk of vasospasm
Nimodipine (CCB)
Started on admission to reduce risk of poor outcome and secondary ischaemia
Bamford Classification of Strokes
And criteria for each type
TACS - all 3 of:
- Homonymous hemianopia
- Unilateral motor/sensory deficit
- Higher cortical dysfunction (speech/hemispatial neglect)
PACS - 2/3 of:
- Homonymous hemianopia
- Unilateral motor/sensory deficit
- Higher cortical dysfunction (speech/hemispatial neglect)
POCS - one of:
- homonymous hemianopia with macular sparing)
- cerebellar syndrome
LACS:
- Pure motor
- Pure sensory
- Mixed sensorimotor
- Dysarthria/clumsy hand
- Ataxic hemiparesis
Millard-Gubler syndrome
Patho and features
Pontine infarct
6th and 7th nerves affected
- Diplopia
- LMN facial palsy
- Loss of corneal reflex
- Contralateral hemiplegia
Immediate medical management of ischaemic stroke
- tPA if <4.5 hours before onset of symptoms and no contraindications
- Aspirin 300mg PO
Secondary prevention of stroke
Aspirin/clopidogrel 300mg for 2 weeks
Then clopidogrel 75mg after
Warfarin instead of asp/clop if cardioembolic stroke or chronic AF
Main cause of TIA
Atherothromboembolism from carotids
Secondary prevention of TIA
Same as for stroke
Aspirin/clopidogrel 300mg for 2 weeks
Then clopidogrel 75mg after
Warfarin instead of asp/clop if cardioembolic TIA or chronic AF
Indications for carotid endarterectomy following TIA/stroke
> 70% unilateral disease
Surgery should be performed within 2 weeks
Stroke risk calculation following TIA
ABCD2 Score (/7)
Age >60 BP > 140/90 Clinical features - Unilateral weakness (2 points) - Speech disturbance Duration - >1 hour (2 points) - 10 mins - 1 hour (1 point) Diabetes
Subdural haematoma patho and main cause
Bleeding from bridging veins between cortex and sinuses
Often due to old injuries, such as deceleration injuries
Subdural haematoma on MRI head
Crescentic haematoma over one hemisphere
Possible midline shift
Indications and type of surgery for subdural haematoma
Indications for surgery:
- Bleed >10mm size
- Midline shift >5mm
- Expanding bleed
- Neurological symptoms/signs
Surgery - 2 burr hole craniostomy to remove clot and irrigate
Hemicraniectomy if swelling
Extradural haematoma on MRI head
Lemon
Eponymous signs of meningism
These signs are more commonly seen in children
Kernig’s sign - With the patient supine and the thigh flexed to a 90° right angle, attempts to straighten or extend the leg are met with resistance
Brudzinski’s sign - Flexion of the neck causes involuntary flexion of knees and hips
Medical management of bacterial meningitis
Ceftriaxone 2g BD IV
(+ampicillin 2g BD IV if >50 years)
Dexamethasone IV QDS
Rifampicin prophylaxis for housemates and partners
Contraindications of LP
Thrombocytopenia or coagulopathy Delaying antibiotics Raised ICP Unstable (cardio and respiratory symptoms) Infection at LP site Focal neurology symptoms
Encephalitis
Main causes
HSV 1 and 2
EBV
CMV
Encephalitis
Investigations
CT - bilateral temporal involvement suggests HSV
Bloods - cultures, viral PCR
LP - increased protein, lymphocytes, PCR
Encephalitis
Management
Aciclovir 10mg/kg/8h IV infusion 14 days
Causes of seizure
2/3 epilepsy is idiopathic
Congenital (NF, Tuberous Sclerosis, TORCH)
Acquired (CVA, SOL)
Other (Withdrawal alcohol/opiates/benzos, metabolic glucose/Na/Ca/urea, infection meningitis, encephalitis)
5 As of complex partial seizures
Aura
Autonomic (change in skin colour/temperature)
Awareness lost (blank stare)
Automatisms (lap smacking, fumbling, chewing)
Amnesia
Petit mal (absence seizure) Features
Abrupt onset and offset
Glazed, blank stare
Lasts <10 seconds
Normal examination
Atonic/akinetic seizure
Sudden loss of muscle tone
No LOC
Driving rules after diagnosis of epilepsy
Cannot drive for 1 year after seizure
Cannot drive HGV for 10 years
Principles of diagnosing epilepsy
- Provoked vs unprovoked
- Generalised vs focal (MRI and EEG)
- Subcategorise (eg absence, myoclonic, tonic clonic)
Anti-epileptics
Sodium valproate (avoid in pregnancy, also enzyme inhibitor) Lamotrigine Carbamazepine (enzyme inducer) Levetiracetam Phenytoin (enzyme inducer)
GCS
Eyes (/4): 4 spontaneously open 3 open to voice 2 open to pain 1 nothing
Speech (/5): 5 spontaneous 4 confused 3 inappropriate speech 2 vocalisations 1 nothing
Motor (/6): 6 obeys commands 5 localises to pain 4 withdraws from pain 3 flexes to pain 2 extends to pain 1 nothing
Indications for CT head in trauma
NICE ‘Head injury’ guideline 2014
CT head within 1 hour:
- GCS <13 on initial assessment
- GCS <15 at 2 hours after injury
- Suspected open or depressed skull fracture
- Signs of basal skull fracture
- Post-traumatic seizure
- Focal neurological deficit
- More than one episode of vomiting since head injury
CT head within 8 hours: - Warfarin - LOC or amnesia + 1 of the following: - Age >65 - Coagulopathy - Dangerous mechanism of injury
Causes of SOL
Vascular
- aneurysm
- AVM
- chronic subdura haematoma
Infective
- TB
- Cerebral abscess
- Cyst
Neoplasm
- Primary
- Metastasis
Granuloma
- TB
- Sarcoid
Idiopathic intracranial hypertension
Features and management
Features (similar to SOL)
- Papilloedema
- Headache
- 6th nerve palsy
- Visual disturbance
Management
- Weight loss
- Acetazolamide to decrease ICP
- Furosemide
- Lumbar-peritoneal shunt is persistent/worsening symptoms despite medical management
Cushing’s reflex - features
Hypertension
Bradycardia
Irregular breathing