Bypass and Flow Reduction for Complex Basilar and Vertebrobasilar Junction Aneurysms

Abstract

Giant aneurysms of the vertebral and basilar arteries are formidable lesions to treat. To evaluate the long-term outcomes of patients with vertebrobasilar aneurysms treated with extracranial-intracranial bypass and flow reduction. We retrospectively reviewed a prospective database of aneurysms cases treated between December 1993 and August 2011. Eleven patients (8 male, 3 female) with 12 aneurysms were treated. There were 3 basilar apex aneurysms, 2 aneurysms of the basilar trunk, and 7 vertebrobasilar junction aneurysms. There were 5 saccular and 7 fusiform aneurysms. All patients underwent extracranial-intracranial bypass and vessel occlusion. Flow was reversed or reduced by complete (n = 6) or partial occlusion of the basilar artery (n = 3) or by occlusion of the vertebral arteries distal to the posterior inferior cerebellar artery (n = 3). Postoperatively (mean follow-up, 71.6 months; range, 4-228; median, 49 months), the bypass patency rate was 92.3% (12/13). The perioperative mortality rate for the initial treatment was 18.2% (2/11). In 4 cases, the aneurysms continued to grow and required further treatment; after re-treatment, 3 of these patients died. Of the initial 11 patients, 6 were treated successfully and 5 died. The mean preoperative modified Rankin Scale score was 2.1 (range, 1-3; median, 2). At last follow-up for all patients, the mean modified Rankin Scale score was 3.45 (range, 1-6; median, 3) and 2.5 (range, 1-4; median, 2.5) for the 6 long-term survivors. Vertebrobasilar aneurysms are challenging lesions with limited microsurgical or endovascular options. Despite aggressive surgical treatment, the long-term outcome remains poor for most patients.