Neuroscience Flashcards
TIA
- investigations
- initial management
- secondary prevention
Investigations: CT scan of head no contrast
Initial management:
give aspirin 300mg
2nd line: clopidogrel 300mg oral
Refer for specialist assessment within 24h
Secondary:
dual antiplatelt therapy
aspirin + clopidogrel for 21 days
or
aspirin + ticagrelor for 30 days
Long-term: clopidogrel 75mg & statin
Stroke
- investigations
- management
Investigations:
CT head without contrast to confirm ischaemic stroke
Management:
Aspirin 300mg immediately
Thrombolysis within 4.5h with alteplase if not contraindicated
dual antiplatelt therapy
aspirin + clopidogrel for 21 days
or
aspirin + ticagrelor for 30 days
If thrombolysis is contra you carry out a mechanical thrombectomy
Subarachnoid haemorrhage
- causes
- symptoms
- investigations
- management
Causes: trauma, berry aneurysm, AVN
Sx: thunderclap headache and meningism
Investigations:
- non-contrast CT head, showing hyperdense blood in the cisterns in a ‘starfish’ appearance
- if CT negative can do a LP 12h after onset to show xanthochromia
Mx:
surgical - endovascular coiling or clipping
medical - nimodipine to prevent vasospasm for 2-3 weeks
Extradural haemorrhage
- place of damage
- Sx
- investigation
- Mx
Damages the middle meningeal artery
Sx - loss of consciousness followed by head trauma (&skull fracture) followed by lucid interval
Investigation - non-contrast CT head
Mx:
ABCDE; oxygen if required
* Urgent neurosurgical opinion
* Manage raised intracranial pressure (ICP)
* Raise head of bed to 30°.
* Analgesia and sedation
* Hypertonic saline or mannitol
* Intubate and hyperventilate
* Definitive management includes craniotomy and haematoma evacuation.
Subdural haemorrhage
- place of damage
- Sx
- investigation
- Mx
Damage to bridging veins
Sx:
acute - similar to EDH
chronic - insidious onset of headache nausea and vomiting
Investigation - non-contrast CT head
Mx:
ABCDE; oxygen if required
* Urgent neurosurgical opinion
* Manage raised intracranial pressure (ICP)
* Raise head of bed to 30°.
* Analgesia and sedation
* Hypertonic saline or mannitol
* Intubate and hyperventilate
* Definitive management includes craniotomy and haematoma evacuation.
Intracranial venous thrombosis
- pathophysiology
- risks
- presentation
- investigation
- Mx
Pathophysiology - clot formation in the cerebral veins or dural venous sinuses and is rare cause of stroke. Cavernus sinus thrombosis is normally due to infection.
Risk - hypercoagulable states
Sx: headache sudden onset, nausea & vomiting, reduced consciousness, papilloedema
Investigation: CT head, CT/MRI venogram, D-dimer, thrombophilia screen
Mx: anticoagulation LMWH followed by long-term warfarin.
Dementia
- types
- presentation
- medical management
- Alzheimer’s disease (AD)
- Vascular dementia (VD)
- Dementia with Lewy bodies (DLB)
- Frontotemporal dementia (FTD)
Presentation
VD - stepwise deterioration
DLB - visual hallucination, REM sleep disorder, Parkinsonism
FTD - personality change and behavioural disturbance
Medical Mx
Alzheimers:
- AChE inhibitors e.g. donepezil, galantamine, and rivastigmine are first line in mild to moderate disease.
- Memantine can be added (NMDA antagonist)
- VD: optimise risk factors
- DLB: same as Alzheimers but antipsychotics and dopamine replacement
- FTD: N/A
Epilepsy
- management
Focal—Lamotrigine or carbamazepine
Tonic-clonic: sodium valproate* or lamotrigine
Absence: ethosuximide or sodium valproate*
Parkinsons
- Sx
- Mx
Symptoms:
- bradykinesia
- resting tremor (4-6hz)
- rigidity (lead pipe or cogwheel)
Mx:
* First-line treatment includes levodopa (combined with carbidopa) for significant functional impairment
* Dopamine agonists (ropinirole)
* MAO-B inhibitors (selegiline)
* COMT inhibitors (entacapone)
Parkinsons + syndromes
Types
Causes
Presentation
Mx
Multiple system atrophy - cerebellar and pyramidal signs
Progressive supra nuclear palsy - vertical gaze palsy and postural instability in the absence of tremor
Corticobasal degeneration
Dementia with Lewy bodies
Sx: fatigue, depression, sleep disturbance, and loss of smell are also common, as well as autonomic dysfunction
Mx: symptomatic
What cranial nerve is damaged in Bells palsy?
Is it UMN or LMN?
CN VII
Unilateral LMN
Myasthenia gravis
Sx
Investigation
Mx
Myasthenic crisis
Sx:
fatiguable muscles through the day
extra ocular muscles affected = diplopia
fatiguable chewing, dysphagia and dysarthria
Investigations
Acetylcholine receptor antibodies (AChR-Ab)
Anti-muscle specific kinase (anti-MuSK) antibodies
CT chest to detect thymic hyperplasia or thymoma
Mx: pyridostigmine
also prednisolone or azathioprine, thymectomy, and monoclonal antibodies such as eculizumab and rituximab
Myasthenic crisis:
* Myasthenic crisis is an acute life-threatening worsening of respiratory muscle weakness that may require ventilatory support.
* It can be triggered by infection, surgery, or certain medications.
* Management consists of intravenous immunoglobulins (IVIGs) or plasmapheresis (plasma exchange).
Guillain-Barré syndrome
Sx
Investigations
Mx
Miller-Fisher syndrome
Sx - progressive weakness affecting lower limbs first, deep tendon reflexes absent, loss of sensation, respiratory muscle involvement
Investigation
LP (raised protein)
Electrophysiology (reduced conduction velocity)
Spirometry
Mx:
IVIG
Thromboprophylaxis (LMWH, stockings)
Intubation and ventilation
Miller–Fisher syndrome is a variant of GBS that presents with a triad of ataxia, areflexia, and ophthalmoplegia. It is associated with anti-GQ1b antibodies.
Neurofibromatosis 1 and 2
Sx of each
Mx
NF1:
* Café-au-lait spots (oval-shaped brown macules)
* Neurofibromas
* Axillary or inguinal freckles
* Optic pathway glioma
* Lisch nodules (iris hamartomas)
* Mild learning difficulties and autism are common
* Seizures
* Skeletal deformities (e.g., sphenoid wing dysplasia, bowing of the tibia and scoliosis)
* Phaeochromocytoma and gastrointestinal tumours
* Renal artery stenosis and hypertension
NF2:
* Early-onset bilateral acoustic neuromas, also called vestibular schwannomas, present with progressive sensorineural hearing loss, tinnitus, and vertigo.
* Other intracranial tumours include meningiomas and ependymomas.
* Cutaneous schwannomas
* Juvenile cataracts
Mx: no curative treatment.
Herpes Simplex Encephalitis
- where does it effect?
- symptoms
- cause
- investigations
- treatment
Temporal lobes
Sx:
fever, headache, psychiatric symptoms, seizures, vomiting
focal features e.g. aphasia
peripheral lesions (e.g. cold sores) have no relation to the presence of HSV encephalitis
Caused by HSV-1 (95%)
Investigations:
CSF: lymphocytosis, elevated protein
PCR for HSV
CT: medial temporal and inferior frontal changes (e.g. petechial haemorrhages) - normal in one-third of patients
MRI is better
EEG pattern: lateralised periodic discharges at 2 Hz
Mx: IV aciclovir
