A Ruptured Aneurysm on the Distal Basilar Artery Fenestration : A Case Report

Abstract

We report a 59-year-old woman who suffered from subarachnoid hemorrhage and had a saccular aneurysm on the fenestration in the distal third of the basilar artery. The anteriorly projecting aneurysm arising at the proximal end of the fenestration was clipped via the subtemporal transtentorial approach. We reviewed 64 cases of aneurysms on the basilar artery fenestration including ours. The group consisted of 32 men and 30 women, and 2 unidentified cases. Their ages ranged from 19 to 78 years. There were 10 patients(15.6%)younger than 30 years old, 15(23.4%)between 30-39, 20(31.3%)between 40-49, 10(15.6%)between 50-59, and 7(10.9%)older than 60, respectively. Fifty four patients(84.3%)presented subarachnoid hemorrhage, 6(9.4%)presented a focal neurological deficit, 2(3.2%)had incidental aneurysms, and in the other 2 the symptoms were unknown. Among the 64 cases, there were 55(86.0%)aneurysms located in the proximal third, 4(6.3%)in the middle third, and 5(7.7%)in the distal third of the basilar artery, respectively. Sixty two aneurysms(96.9%)arose at the proximal end of the fenestration, and 2 aneurysms arose distally. The aneurysms projected anteriorly in 40 patients, posteriorly in 12, and anteriorly and posteriorly in 2. In the other 10 patients the direction of the aneurysms could not be identified. The surgical approach for distal third basilar trunk aneurysms has mostly been taken via the subtemporal approach with or without tentorial incision. As an other approach, coil embolization via the intravascular approach has been reported.