INCIDENCE OF SILENT LACUNAR LESION IN NORMAL ADULTS AND ITS RELATION TO CEREBRAL BLOOD-FLOW AND RISK-FACTORS

Background and Purpose: There are few reports comparing incidence of silent lacunar lesions detected by magnetic resonance imaging and cerebral blood flow in neurologically normal adults. Methods: We studied the incidence of such lesions and its relation to cerebral blood flow and risk factors in 246 neurologically normal adults (145 men, mean age 62 years; 101 women, mean age 60 years) who received health screening examinations of the brain. Results: Thirty-two subjects (13%) had possible silent lacunar lesions (66% of these were recognized by both T1- and T2-weighted image). The regional cerebral blood flow measured by the xenon-133 inhalation method was significantly lower in subjects with silent lacunes than in those without (p < 0.02). Cerebral blood flow was mildly but significantly decreased in those with silent lacunes (p < 0.05). Periventricular hyperintensity was closely related to silent lacune (p < 0.01). However, there was no significant difference in cerebral blood flow between subjects with and without apparent periventricular hyperintensity. Conclusions: Silent lacunar lesion was closely related to decrease of cerebral circulation and may be an important risk factor for symptomatic cerebrovascular disease.