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