Pattern of vessel involvement in cerebral atherosclerosis

Attention is drawn to a previous study by the authors in which the severity and extent of cerebral atherosclerosis in the Japanese and Minnesota populations were reported. This study indicated a possible ethnic difference in severity of atherosclerosis in the arterial circle of Willis between the Japanese and Minnesota populations in the direction of greater involvement in the Japanese. 375 Japanese autopsies were added to the series since that report.

The present study shows that there is a difference in the pattern of vessel involvement between the two groups. In the Minnesota cases first lesions are found primarily in the large caliber vessels of the circle of Willis, whereas in the Japanese cases some small caliber vessels show frequencies of single plaques almost equal to those in the large vessels. Moreover, a comparison of the degree of atherosclerosis in individual vessels indicates that it is in the smaller vessels that the Japanese cases present more severe involvement than the Minnesota cases.