Abstract
A case in which an arteriovenous malformation (AVM) fed by an azygos anterior cerebral artery (ACA) was associated with multiple intracranial aneurysms is reported. The patients was a 44-year-old woman admitted because of a subarachnoid hemorrhage. A cerebral angiogram revealed an AVM fed by an azygos ACA in the right frontal lobe associated with aneurysms in the ACA and in the cavernous portion of the right carotid artery. Although total extirpation of the AVM was performed, the aneurysms were treated conservatively. A cerebral angiogram taken 7 months postoperatively showed a reduction in the size of the ACA aneurysm, but the aneurysm in the cavernous portion remained unchanged. It was assumed that the azygos ACA and AVM occurred almost simultaneously before 44 days of gestation. However, the developmental cause of these two vascular anomalies is unknown. The ACA aneurysm appeared to be formed by hemodynamic stress because it shrunk in size spontaneously after extirpation of the AVM. This is consistent with the concept that treatment of aneurysms in feeders after extirpation of AVMs is not necessary if a risk of injury to surrounding brain tissue is involved. The intracavernous carotid aneurysm might have been a congenital anomaly since it was situated in an artery not influenced by hemodynamic stress.
