Neurology Flashcards
Stroke
acute neurological condition resulting from a disruption in cerebral perfusion either due to ischaemia (ischaemic stroke) or haemorrhage (haemorrhage stroke)
characterised by acute onset focal neurological deficits the pattern being dictated by the affected vessel and last >24h
4th most common single cause of death in UK
Transient ischaemic attack (TIA)
acute onset focal neurological deficits which resolve within 24h
Middle cerebral artery (MCA) stroke symptoms
Most commonly affected vessel
-contralateral weakness/hemiparesis and sensory loss
(more marked in upper limbs & lower half of face than in lower limbs)
-contralateral homonymous hemianopia
-gaze deviation (if superior MCA division)
-Aphasia
Broca’s/expressive (if superior MCA branch)
Wernicke’s/receptive (if inferior MCA branch)
conductive aphasia (if inferior MCA branch)
-Hemineglect, usually contralateral (if non dominant hemisphere)
Anterior cerebral artery (ACA) stroke symptoms
-contralateral hemiparesis/weakness & sensory loss (more pronounced in lower limbs than upper limbs)
-dysarthria
-limb apraxia (inability to perform precise, voluntary movements)
-frontal release sign
urinary incontinence
Posterior cerebral artery (PCA) stroke symptoms
- contralateral homonymous hemianopia with macular sparing
- contralateral sensory loss especially light touch/pinprick/proprioception
- memory deficits
- if dominant (left hemisphere): visual agnosia, expressive aphasia
- if non dominant (right hemisphere): prosopagnosia (inability to recognise faces)
Posterior inferior cerebellar artery (PICA) stroke symptoms
lateral medullary syndrome (Wallenberg syndorme)
ipsilateral nystagmus, vertigo, limb ataxia, Horner syndrome, ↓pain & temp sensation to face, bulbar palsy (dysphagia/dysphonia)
Anterior inferior cerebellar artery (AICA) stroke symptoms
lateral pontine syndrome
contralateral loss of pain & temp sensation
ipsilateral limb & gait ataxia, loss of facial pain & temp sensation, facial muscle weakness, ↓lacrimation, vertigo, nystagmus, hearing loss, Horner syndrome
Basilar artery stroke
locked in syndrome
Weber’s syndrome
stroke in branches of PCA supplying midbrain
Ipsilateral CNIII palsy
contralateral weakness of upper & lower extremities
Lenticulostriate arteries (Deep MCA branches) stroke symptoms
No cortical signs (e.g. neglect/visual loss/aphasia)
presents as isolated hemiparesis, hemisensory loss, limb ataxia
Oxford stroke classification (Bamford classification)
asses the following features:
- unilateral hemiparesis and/or hemisensory loss of face, arm, leg
- homonymous hemianopia
- higher cognitive dysfunction e.g. aphasia
Total anterior circulation infarct (Bamford classification)
~15% of strokes
involves MCA & ACA
Presents with
- unilateral hemiparesis and/or hemisensory loss of face, arm, leg
- homonymous hemianopia
- higher cognitive dysfunction e.g. aphasia
Partial anterior circulation infarct (Bamford classification)
~25% of strokes
involves smaller arteries of anterior circulation
presents with 2 of
- unilateral hemiparesis and/or hemisensory loss of face, arm, leg
- homonymous hemianopia
- higher cognitive dysfunction e.g. aphasia
Lacunar infarcts (Bamford classification)
~25% of strokes
involves perforating arteries around basal ganglia/thalamus/internal capsule
Presents with 1 of
- unilateral weakness and/or sensory deficit of face/arms/legs
- pure sensory stroke
- ataxic hemiparesis
Posterior circulation infarcts (Bamford classification)
~25%
involves vertebrobasilar arteries
Presents with 1 of
- cerebellar/brainstem syndromes
- LOC
- isolated homonymous hemianopia
Assessment & investigations of stroke
FAST assessment
ROSIER score
non-contrast CT head (GOLD standard)*
serum glucose* (to exclude hypoglycaemia)
FBCs/U&Es/LFTs/Coag
ECG (check for AF)
Consider MRI & carotid artery doppler
Differential diagnosis for stroke
Hypoglycaemia (must be excluded) Seizure disorders complicated migraines subdural haematoma hypertensive encephalopathy brain tumour
Ischaemic stroke
A stroke due to vascular occlusion/stenosis causing ischaemia, leading to cerebral infarction due to insufficient cerebral blood flow
~85% of all strokes
Subtypes of ischaemic strokes
Thrombotic e..g thrombus in large vessel such as the carotids
Embolic e.g. embolus from heart in AF
global cerebral ischaemia e.g. in cardiac arrest
Risk factors for ischaemic stroke
AF ↑ age FH of stroke previous ischaemic stroke HTN smoking hyperlipidaemia previous TIA peripheral arterial disease carotid artery stenosis diabetes
Presentation of ischaemic stroke
sudden onset of focal neurological deficits depending on which vessel is involved
impaired consciousness (but LOC is uncommon in stroke)
nausea
vomiting
headache
Ischaemic stroke on CT
hyperdense occluded vessel
hypo attenuated brain parenchyma (dark)
Management of ischaemic stroke
Reperfusion therapy:
IV thromobolysis e.g. alteplase/tenecteplase
give within ≤4.5h of symptom onset
NB a hemorrhagic stroke must be excluded
–
Thrombectomy
offer in addition to IV thrombolysis if within 6h
offer within 24h if confirmed anterior circulation stroke
BP control
Aspirin 300mg
rehab PT/OT/SALT
Long term secondary prophylaxis in ischaemic stroke
1st line: 75mg clopidogrel
2nd line: 75mg aspirin + MR dipyridamole