To assess the role of hypertension in asymptomatic cerebral lacunae, we evaluated cranial computed tomography in 76 untreated hypertensive patients, 173 hypertensive patients treated with antihypertensive drugs, and 69 agematched normotensive control subjects who were more than 60 years of age and without a history of stroke. Cerebral lacunae were diagnosed by computed tomography as a hypodense lesion less than 15 mm in diameter seen on a single 10-mm scan section. The factors contributing to lacunae were determined by stepwise discriminant analysis. Single or multiple cerebral lacunae were revealed in 27.6% (21 of 76) of untreated hypertensive patients, 17.3% (30 of 173) of treated hypertensive patients, and 7.2% (5 of 69) of normotensive control subjects. Incidence of lacunae was significantly higher in hypertensive patients than normotensive control subjects. Stepwise discriminant analysis showed that the most strongly contributing factor for lacunae was the grade of hypertensive retinopathy in untreated hypertensive patients and mean blood pressure in treated hypertensive patients. Asymptomatic cerebral lacunae were frequently detected by computed tomography in elderly patients with essential hypertension. The severity and duration of hypertension correlate positively with this type of vascular complication in hypertension.