[Aneurysm of peripheral cerebral arteries with developmental anomaly of the anterior cerebral artery].
We report a 71-year-old woman who was initially admitted because of a ruptured internal carotid aneurysm, and found to have an aneurysm of the terminal portion (A5 portion) of pericallosal artery. Both of the aneurysms were surgically treated at one stage operation. A saccular aneurysm of the pericallosal artery was verified at operation. Right internal carotid angiography disclosed that medial part of the right anterior cerebral hemisphere was supplied by the right callosomarginal artery, and that unpaired pericallosal artery made a trifurcation at A5 portion, where the saccular aneurysm arose. According to Baptista's classification, anomaly of the anterior cerebral artery (ACA) in this patient was bihemispheric ACA type. Distal ACA aneurysms almost always locate at or near the genu of corpus callosum, either in pericallosal-callosomarginal or in pericallosal-frontopolar junction. In reviewing the literature, we were able to find 14 cases, including ours, of aneurysms located beyond either pericallosal-callosomarginal junction or the genu of corpus callosum. Also the possible role of hemodynamic stress caused by vascular anomaly for aneurysm formation are discussed.
D000368:Aged; D002533:Cerebral Angiography; D002536:Cerebral Arteries / Q000002:abnormalities*; D003399:Craniotomy / Q000379:methods; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery