Clinical Syndromes Lacunar Stroke Laci

Occlusion of deep penetrating arteries produces subcortical infarction characterised by preservation of cortical function - language, other cognitive and visual functions.

Clinical syndromes are distinctive and normally result from long-standing hypertension. In 80%, infarcts occur in periventricular white matter and basal ganglia, the rest in cerebellum and brain stem. Areas of infarction are 0.5-1.5 cms in diameter and occluded vessels demonstrate lipohyalinosis, microaneurysm and microatheromatous changes. Lacunar or subcortical infarction accounts for 17% of all thromboembolic strokes and knowledge of commoner syndromes is essential.

1. Pure motor hemiplegia

Putamen

Thalamus

Thalamus

Lesion in posterior limb of internal capsule

Clinical: Equal weakness of contralateral face, arm and leg with dysarthria Vessel(s): Lenticulostriate A.

2. Pure sensory stroke

Lesion in VPL nucleus of thalamus

Lesion in VPL nucleus of thalamus

Clinical: Numbness and tingling of contralateral face and limbs. Sensory examination may be normal

Vessel(s): Thalamogeniculate A.

3. Dysarthria/clumsy hand

Lesion in dorsal pons x ^

Clinical: Dysarthria due to weakness of ipsilateral face and tongue associated with clumsy but strong contralateral arm. Vessel(s): Perforating branch of Basilar A.

4. Ataxic hemiparesis

Lesion in ventral pons ^ (interruption of pontocerebellar fibres)

Clinical: Mild hemiparesis with more marked ipsilateral limb ataxia Vessel(s): Perforating branch of Basilar A. (This syndrome can also be produced by anterior capsular lesions)

5. Severe dysarthria with facial weakness

Lesion in anterior limb of internal capsule

Clinical: Dysarthria, dysphagia and even mutism occur with mild facial and no limb weakness or clumsiness.

Vessel(s): Lenticulostriate A.

Sensorimotor syndromes are common although anatomical basis is obscure. A recent Stroke Data Bank survey showed the commonest presentations to be: -

Pure motor hemiplegia 57% Sensorimotor 20% Ataxic hemiparesis 10% Pure sensory 7% Dysarthria/Clumsy hand 6% Investigations MRI is superior to CT in demonstrating lacunae, although either may occasionally misdiagnose a small resolving haematoma. Confirmation of lacunar stroke may save patients from unnecessary investigations for carotid and cardiac embolic source.

Prognosis For all syndromes this is encouraging. Careful control of blood pressure and the use of aspirin usually prevents recurrence. Multiple lacunar infarctions - '├ętat lacunaire' - results in shuffling gait, pseudobulbar palsy and subcortical dementia.

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Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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