A case of porencephaly associated with aneurysm.

A case of aneurysm of the middle cerebral artery with congenital porencephaly in the same region is reported. The cyst was opened and the aneurysm was wrapped with a muscle strip. The resected specimen of the cyst wall contained a parenchymal layer with hemosiderinladen macrophages. It is speculated that bleeding from the aneurysm during the perinatal period caused the porencephaly.