Stroke
- Stroke syndromes
5% of patients presenting with a stroke syndrome does not have a cerebrovascular pathology.
Transient ischemic attack
- A neurological deficit that resolves within 24 hours (although >80% resolves within 30 minutes).
- Most commonly associated with thrombotic strokes.
- Associated with 5% risk of stroke per year.
Ischaemic stroke syndromes
Anterior cerebral artery infarct
- Contralateral leg weakness greater than arm weakness
- With mild sensory defects
- Perseveration of speech and motor actions. Responds slowly.
Middle cerebral artery infarct
Most common
- Contralateral weakness
- If dominant hemisphere is involved, aphasia (receptive and/or expressive) may be present
- If non-dominant hemisphere is involved, inattention, neglect, or extinction on double-simultaneous stimulation may be present.
* Constructional apraxia (demonstrated by inability to draw clock and fill in the appropriate numbers).
* Dysarthric but not aphasia
- Homonymous hemianopsia and gaze preference towards the side of the infact.
- (In right-handed patients, and 80% of left-handed patients, the left hemisphere is the dominant sphere)
Posterior cerebral artery infarct
- Minimal motor involvement
- Reduced light-touch and pinprick sensation
- Some visual abnormalities
Vertebrobasilar syndrome
Occurs when posterior circulation which suppliers the brainstem, cerebellum, and visual cortex is disrupted.
- Dizziness
- Vertigo
- Diplopia
- Dysphagia
- Ataxia
- Cranial nerve palsies
- Bilateral limb weakness
- Crossed neurologic deficiency
* ipsilateral cranial nerve deficit
AND
* contralateral motor weakness
Basilar artery occlusion
- Severe quadriplegia
- Coma
- Lock-in syndrome
-> lesions in the pontine tectum causing complete muscle paralysis except for upward gaze
Cerebellar infarct
- Drop attack, with sudden onset of inability to walk or stand
- Central vertigo, headache, nausea, vomiting
- Neck pain
- Some cranial nerve abnormalities
- After a delay of 6-12 hours, 1/3 of patients will develop significant oedema with subsequent increased brainstem pressure, and decreased level of consciousness
- Require surgical decompression, diuretic, and corticosteroid to prevent oedema and relieve pressure
Lacunar infarct
- Pure motor or sensory deficits due to infarcts of small penetrating arteries
- Commonly associated with chronic hypertension
- Lesions are located in the pons and the basal ganglia.
Haemorrhagic stroke syndrome
Intracerebral haemorrhage
May be clinically indistinguishable from cerebral infarction.
Headache, nausea, vomiting often precede the neurological deficit
- Contralateral hemiplegia
- Contralateral hemianesthesia
- Contralateral hemianopsia
- Aphasia (if dominent hemisphere is invovled)
OR
Neglect (if non-dominant hemisphere is involved).
Compared with ischaemic infarct: lethargy and hypertension is more common in haemorrhagic stroke.
Bleeding is usually localised to the putamen, thalamus, pons, or cerebellum in patients with hypertensive ICH.
Cerebellar haemorrhage
- Sudden onset
- Dizziness and vomiting
- Marked truncal ataxia
- Inability to walk
- May be associated with gaze palsies, increasing stupor.
- May rapidly progress to coma and herniation.
Subarachnoid haemorrhage (SAH)
More common in women, but in <40, more in men.
- Sudden onset of severe, constant headache (often occipital or nuchal)
- Vomiting
- Decreased level of consciousness
Hunt and Hess classification of SAH
- Grade I: Asymptomatic or minimal headache and mild nuchal rigidity
- Grade II: Moderate to severe headache, nuchal rigidity, and no neurologic deficit other than cranial nerve palsy
- Grade III: Drowsiness, confusion, mild focal deficit
- Grade IV: Stupor, moderate to severe hemiparesis, possible early decerebrate rigidity, and vegatative disturbance
- Grade V: Deep coma, decerebrate rigidity