Neurology Flashcards
What is a TIA?
- sudden onset
- brief episode of neurological deficit
Pathophysiology of TIA
- temporary, focal cerebal ischaemia
- lack of O2 and nutrients to brain
- without infarction → no irreversible cell death
Features of a TIA
- symptoms are maximal at onset
- usually lasts 5-15 mins
- classical definition = lasts <24hrs
Risk factors for TIA
- age
- HTN
- smoking
- diabetes
- a fib
- the pill
- males
- black people
Causes of a TIA
atherothromboembolism from carotid artery
cardioembolism
- in a fib
- after an MI
- valve disease/prosthetic valve
hyperviscosity
hypoperfusion
Presentation of a TIA
- amaurosis fugax
- aphasia
- hemiparesis
- hemisensory loss
- hemianopic visual loss
What symptoms do not indicate a TIA on their own?
- syncope
- dizziness
- temporary loss of consciousness
- temporary memory loss
- gradual onset
What scoring tool measures the risk of a stroke after a TIA?
ABCD2 score
- age
- BP
- clinical features
- duration of TIA
- DM
- gives 2 day risk
Investigations for TIA
- diffusion weighted MRI/CT brain
- carotid imaging → doppler US then angiography if stenosis found
- bloods
- ECG
- echo
Management of TIA
- loading dose 300mg aspirin
- control BP/cholesterol
- no driving for 1 month
- antiplatelet therapy = daily 75mg aspirin
- anticoagulation if AF
- carotid endarterectomy
What is a stroke?
- rapid onset neurological deficit
- lasting over 24hrs
- poor blood flow to brain → cell death
What are the 2 types of stroke?
ischaemic 85%
- blood clot in blood vessel to brain
haemorrhagic 15%
- bleed in small blood vessel in/around brain
urgent CT/MRI to determine type → guides treatment
Risk factors for ischaemic stroke
- age
- male
- HTN
- smoking
- diabetes
- recent/past TIA
- IHD/AF
- the pill
- black/asian
- PVD
Causes of ischaemic stroke
- small vessel occlusion by thrombus
- atherothromboembolism
- cardioembolism
- hyperviscosity
- hypoperfusion
- vasculitis
- fat emboli from long bone fracture
- venous sinus thrombosis
Presentation of cerebral infarcts
depends on site
ACA
- contralateral weakness and sensory loss of lower limb
MCA
- contralateral motor weakness/sensory loss
- speech issues
- contralater hemiplegia
- UMN facial weakness
- dysphagia
- homonymous hemianopia
- visuo-spatial deficit
Presentation of brainstem infarcts
depends on site
- quadriplegia
- facial numbness/paralysis
- vision disturbances
- speech impairment
- vertigo → N&V
- locked-in syndrome
What are lacunar infarcts?
- small infarcts
- occlusion of a single perforating artery supplying a subcortical area
occurs in
- internal capsule
- basal ganglia
- thalamus
- pons
Presentation of lacunar infarcts
depends on site → one of:
- sensory loss
- unilateral weakness
- ataxic hemiparesis
- dysarthria
Management of ischaemic strokes
- exclude haemorrhagic stroke
- loading dose 300mg aspirin
- antiplatelet therapy → 300mg aspiring daily for 2 weeks then clopidogrel
- anticoagulation if AF
- thrombolysis → IV alteplase within 4.5hrs
- mechanical thrombectomy
acute stroke unit
- rehabilitation
- swallowing/feeding support
What are the 4 types of haemorrhagic stroke?
- intracerebral haemorrhage
- subarachnoid haemorrhage
- extradural haemorrhage
- subdural haemorrhage
What is an intracerebral haemorrhage?
- sudden bleeding into brain tissue
- rupture of blood vessel in brain
- leads to infarction (O2 deprivation)
- pooling blood increases ICP
Risk factors for intracerebral haemorrhage
- HTN
- age
- alcohol
- smoking
- diabetes
- anticoagulation
- thrombolysis
- secondary to ischaemic stroke
Pathophysiology of increased ICP
- pressure on skull/brain/blood vessels
- CSF obstruction
- midline shift
- tentorial herniation
- coning
Presentation of intracerebral haemorrhage
similar to ischaemic stroke
pointers to haemorrhage
- sudden loss of consciousness
- severe headache
- meningism
- coma