Stroke Infarction Flashcards
What is the pathology of ischaemic stroke?
Acute occlusion of an intracranial vessel leading to hypoxia and infarction; if blood flow restored w/o significant infarction = TIA.
What is the aetiology of ischaemic stroke?
- DM, HTN, smoking, hypercholesterolemia
- FHx
- AF, valvular lesions, cardiac congenital defects, hypercoaguable states, vasculitis
What are the symptoms of ACA occlusion?
- Contralateral hemiplegia
- Gait apraxia
- Abulia (severe apathy)
- Urinary incontinence
- Lower limb sensory loss
What are the symptoms of MCA occlusion?
-Contralateral hemiplegia
-Homonymous hemianopia
-Contralateral sensory loss
-Dysarthria, dysphasia
Non-dominant symptoms: aphasia, neglect, contructional apraxia.
What are the symptoms of posterior cerebral artery occlusion?
Homonymous hemianopia +/- macular sparing Contralateral hemiplegia Ataxia/hemiballismus Visual agnosia Cortical blindness
What are the symptoms of posterior inferior cerebellar artery occlusion?
Syncope Vertigo Hemiplegia Dysarthria Ipsilateral face numbness Contralateral limb numbness
What are the symptoms of basilar artery occlusion?
Dizziness, vertigo, diplopia, dysarthria, facial numbness, ipsilateral hemiparesis
What Ix in ischaemic stroke?
CT, MRI, MR angiography, carotid dopplers, ECG, echo.
Rx ischaemic stroke?
-Medical: aspirin, clopidogrel, dipyramidole, anticoagulation.
Thrombolysis as indicated.
-Collateral blood flow BP dependent - don’t lower BP unless signs of malignant HTN.
-Surgical: carotid endarterectomy
What is a stroke?
Sudden on set of neurological deficits of a vascular basis with infarction of CNS tissue
What is a TIA?
Sudden onset of neurological deficits of a vascular basis without infarction (i.e. resolution)
Pathophysiology of small vessel / lacunar ischaemic strokes?
Chronic HTN and DM cause vessel wall thickening and decreased luminal diameter
Where do small vessel / lacunar strokes generally occur?
Small penetrating arteries: primarily basal ganglia, internal capsule, thalamus
What are the different mechanisms of ischaemic stroke?
- Arterial thrombosis
- Cardioembolic
- Systemic hypoperfusion
What is the most common mechanisms of hemorrhagic stroke?
Hypertensive: rupture of small micro aneurysms causing intraparenchymal haemorrhage
What are the most common sites of hemorrhagic stroke?
Putamen, thalamus, cerebellum, pons
ACA stroke syndrome?
Contralateral leg paresis and sensory loss
MCA stroke syndrome?
Proximal occlusion involves:
- Contralateral weakness and sensory loss of face and arm
- Cortical sensory loss
- +/- contralateral homonymous hemianopia or quadrantanopia
- L hemisphere: aphasia
- R hemisphere: neglect
- eye deviation towards the side of the lesion and away from the weak side
PCA stroke syndrome?
- Contralateral hemianopia or quadrantanopia
- Midbrain findings (CNIII/IV palsy/pupillary changes, hemiparesis)
- Thalamic findings: sensory loss, amnesia, dec LOC
- If bilateral: cortical blindness or prospagnosia
Basical artery stroke syndrome?
Locked in syndrome:
- Quadriparesis
- Dysarthria
- Impaired eye movements
PICA stroke syndrome?
Lateral medullary / Wallenburg syndrome:
- Ipsilateral ataxia
- ispilateral Horner’s
- ipsilateral facial sensory loss
- contralateral limb impairment of pain & temp
- nystagmus vertigo
- N/V
- Dysphagia
- Dysarthria
Anterior spinal artery stroke syndrome?
Medial medullary infarct:
- contralateral hemiparesis
- contralateral impaired proprioception and vibration
- ipsilateral tongue weakness
Lacunar infarct stroke syndrome to posterior limb of internal capsule?
-Pure motor: posterior limb of internal capsule => contralateral leg, arm, face
Thalamic lacunar infarct stroke syndrome?
Pure sensory loss: hemisensory loss