Lacunar stroke
Small subcortical infarct, under 1.5 cm, from occlusion of a single penetrating artery, most often caused by hypertensive lipohyalinosis, producing one of five classic pure motor, pure sensory, ataxic hemiparesis, dysarthria-clumsy hand, or mixed sensorimotor syndromes without cortical signs, diagnosed by MRI and managed with the standard acute stroke pathway plus aggressive antiplatelet, statin, and blood pressure secondary prevention.
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What this article covers
- Overview
Definition: lacunar stroke is a small subcortical infarct, less than 1.5 cm in diameter, caused by occlusion of a single small penetrating artery arising from a larger cerebral artery, most commonly the middle cerebral or basilar artery.
- Epidemiology
Proportion of ischemic stroke: lacunar infarcts account for a substantial minority of all ischemic strokes and are one of the most common recognized stroke subtypes.
- Risk factors
Chronic hypertension: the dominant and most consistently identified risk factor, driving vessel wall damage at the level of the penetrating artery.
- Pathophysiology
Lipohyalinosis: chronic hypertension causes fibrinoid necrosis and hyaline thickening of the wall of small penetrating arteries, narrowing the lumen and predisposing to occlusion.
- Clinical features
Pure motor stroke: contralateral hemiparesis affecting the face, arm, and leg roughly equally, from a lacunar infarct in the posterior limb of the internal capsule or the basis pontis, without sensory, visual, or cognitive involvement.
- Differential diagnosis
Cortical (middle cerebral artery) stroke: presents with aphasia, hemineglect, or a visual field cut, cortical signs that are absent in lacunar stroke, and typically involves face and arm more than leg.
- Diagnosis
Clinical syndrome plus imaging establishes the diagnosis: a classic lacunar syndrome (pure motor, pure sensory, ataxic hemiparesis, dysarthria-clumsy hand, or mixed sensorimotor) without cortical…
- Management
First, follow the standard acute ischemic stroke pathway: assess eligibility for intravenous thrombolysis (alteplase 0.9 mg/kg IV, maximum 90 mg, with 10% given as a bolus over 1 minute and the…
- Complications
Recurrent lacunar or other ischemic stroke: the most direct complication of uncontrolled hypertension, diabetes, or hyperlipidemia after the index event.
- Prognosis
Individual event prognosis is generally favorable: many patients have substantial or complete recovery, better on average than after a comparably sized cortical infarct, because eloquent cortical function is spared.
- Prevention
Blood pressure control below 140/90 mmHg is the single most effective preventive measure for first and recurrent lacunar stroke.
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Related articles
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Basilar artery occlusion is a posterior circulation large-vessel stroke that threatens the brainstem, cerebellum, and thalami, presenting with rapidly progressive quadriparesis, cranial nerve palsies, and impaired consciousness, up to locked-in syndrome or coma. Diagnosis requires urgent CT angiography, and management is emergent reperfusion with IV alteplase followed by mechanical thrombectomy in eligible patients.
- Cerebellar stroke
Cerebellar stroke, ischemic or hemorrhagic infarction of the cerebellum, presents with vertigo, truncal ataxia, dysarthria, and limb incoordination and is diagnosed with brain MRI when CT is falsely reassuring. Its defining danger is delayed swelling that compresses the brainstem and fourth ventricle, which is treated with emergent decompressive suboccipital craniectomy.
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