Stroke Flashcards
Define stroke
The damaging or killing of brain cells starved of oxygen as a result of the blood supply to part of the brain being cut off
Define TIA
A stroke that recovers within 24 hours from the onset of symptoms
Define stroke syndrome
Constellation of signs and symptoms produced due to occlusion or damage of an artery supplying part of the brain
What types of stroke are there?
Ischaemic = 85%
Haemorrhage = 10%
Other (venous thrombosis, arterial dissection) = 5%
Where can the clot come from regarding a stoke?
Brain
Carotid arteries = commonly at bifurcation
Heart = AF (warfarin given), valvular disease
Vertebral/basilar arteries
Aorta
Where foramen do the vertebral arteries go through?
Foramen magnum
What foramen do the internal carotid arteries go through?
Carotid canal
Outline a stroke from the anterior cerebral artery
Supplies = Medial brain, paracentral lobules (micturition), corpus callosum
Motor/sensory = lower limb
Present = contralateral, flaccid paralysis followed by spasticity (UMN signs), loss of all sensory, loss of voluntary control of micturition, split brain syndrome, alien hand syndrome
Outline split brain syndrome
Partial/complete severing of the corpus callosum
Each hemisphere will have its own perception, concepts and impulses
L visual field is sent to the R visual cortex, the R visual cortex communicates across the corpus callosum to the speech control centre on the L = pts cant explain what they’ve seen
Outline alien hand syndrome
Limbs acting seemingly on their own, without control over the actions
Outline a stroke from the middle cerebral artery
Supplies = superior temporal, lateral aspect of frontal/parietal
Result = oedema (raised ICP)
Motor/sensory = face, upper limb
Present = contralateral, flaccid paralysis followed by spasticity (UMN signs), loss of all sensory in upper limb and face
Proximal occlusion = face/arm motor, internal capsule carrying motor fibres of face/arms/legs
Distal occlusion = face arms motor
Visual = proximal: contralateral homonymous hemianopia, distal: contralateral homonymous superior or inferior quadrantanopia
Dominant side (L) = Speech: global aphagia, brocas aphasia, wernickes aphasia
Non dominant (R) = hemispatial neglect, tactile extinction, visual extinction, anosognosia
Outline a stoke from the posterior cerebral artery
Supplies = occipital, inferior temporal, midbrain, thalamus
Present = contralateral homonymous hemianopia with macular sparing
Outline a stoke from the cerebellar artery
Supplies = cerebellum, brainstem
Present = distal: DANISH (Dysdiadochokinesia, ataxia, nystagmus, intention tremor, slurred speech, hypotonia), proximal: brainstem as well, ipsilateral cranial N signs
Outline a stroke from the basilar artery
Supplies = occipital lobe, midbrain, thalamus
Present = distal : bilateral, proximal: locked in syndrome
Outline a stroke from the lenticulostriate artery
Supplies = internal capsule (posterior: limbs, genu: face), basal ganglia
Present = contralateral paralysis of face and limbs, parkinsonian features
PURE MOTOR
(Lacuna infarcts)
Outline a stroke from the thalamoperforator artery
Supplies = thalamus (relay station for sensory before primary sensory cortex)
Present = contralateral sensory loss of face and limbs
PURE SENSORY
What are lacunar stroke syndromes?
Most common type of stroke
Occlusion of small penetrating arteries that supply deep structures
How does a haemorrhagic stroke appear on imaging?
White area
How does an infarct stroke appear on imaging?
Hypodense
Loss of grey/white matter differentiation
Give a differential diagnosis for weakness/dysphagia
HEMI
Hypoglycaemia
Epilepsy
Migraine
Intracranial tumour/infection
What would result from an occluded anterior spinal artery?
Midline vessel = bilateral effect
Loss of spinothalamic tract modalities below the occlusion
UMN signs below the level of the occlusion
What would result from an occluded posterior spinal artery?
Less commonly occluded
Unilateral effects
Ipsilateral loss of dorsal column modalities below the occlusion
