Clinical features of aneurysms of the posterior cerebral artery: a 15-year experience with 21 cases.

Objective: To investigate the characteristic clinical behavior and develop guidelines for the clinical management of posterior cerebral artery aneurysms, we reviewed 21 cases treated during a 15-year period.

Methods: Between 1988 and 2002, we treated 21 patients (10 male, 11 female; mean age, 49.8 yr) with posterior cerebral artery aneurysms at Kumamoto University Hospital and its affiliated hospitals. Data relating to the clinical, radiological, and surgical approaches were analyzed.

Results: There were 20 saccular aneurysms, 6 of which were giant or large aneurysms, and 1 dissecting aneurysm. Of the 21 patients, 15 presented with subarachnoid hemorrhage; in 3 patients, an unruptured saccular aneurysm was found incidentally during an evaluation for other cerebral pathological conditions. Two patients presented with progressive homonymous hemianopsia because of the mass effect of the aneurysm, and 1 patient experienced the sudden onset of homonymous hemianopsia because of thrombosis of the aneurysm and afferent artery. Open or endovascular surgery was performed in 19 patients: 14 made a good recovery, 2 had a moderate disability because of angiospasm or infarction after aneurysm trapping, 1 had a severe disability because of angiospasm and cerebral contusion, and 2 died because of severe angiospasm. Of 2 conservatively treated patients, 1 made a good recovery but the other died as a result of rebleeding.

Conclusion: Posterior cerebral artery aneurysms have specific clinical characteristics compared with aneurysms located elsewhere. The aneurysmal site and size and the surgical technique did not significantly influence treatment outcomes.