Stroke, Lacunar

Small lesions (usually < 1.5 cm in diameter) occur in the distribution of

• Short, penetrating arteries in the basal ganglia

• Pons

• Cerebellum

• Internal capsule

• Thalamus

• Deep cerebral white matter (less common) (Table 24–3)

Risk factors include poorly controlled hypertension and diabetes mellitus

Generally has a good prognosis, with partial or complete resolution often occurring over 4–6 weeks

There are several clinical syndromes

• Contralateral pure motor hemiparesis or pure hemisensory deficit

• Ipsilateral ataxia with crural paresis

• Dysarthria with clumsiness of the hand

Deficits may progress over 24–36 hours before stabilizing

Sometimes visible on CT scans as small, punched-out, hypodense areas, but in other patients no abnormality is seen

In some instances, patients with a clinical syndrome suggestive of lacunar infarction are found to have a severe hemispheric infarct on CT scanning

Diffusion-weighted MRI is sensitive to acute lesions, which later evolve into areas of T2 hyperintensity and eventually into small, punched-out, cerebrospinal fluid–filled spaces

Treatment is similar to transient ischemic attack and cerebral infarction

Control hypertension or diabetes mellitus

Avoid tobacco use

Anticoagulation is not indicated

Aspirin, 325 mg once daily orally, is of uncertain benefit