The Natural History of Radiographically Defined Vertebrobasilar Nonsaccular Intracranial Aneurysms

Abstract

Vertebrobasilar nonsaccular intracranial aneurysms (VBNIA) are characterized by dilatation, elongation, and tortuosity of the vertebrobasilar system. The medical records and imaging of patients with vertebrobasilar fusiform aneurysms or dolichoectasia between 1989 and 2001 were reviewed. Prospective follow-up was obtained. One hundred and fifty-nine patients were identified (74% male) with 719 patient years of follow-up. Presenting events included: hemorrhage (3%), ischemia (28%), and compression (22%). The remainder were incidental. The 1-, 5-, and 10-year risk of cerebral infarction (CI) due toVBNIA is 2.7, 11.3, and 15.9% respectively. The risk of recurrent CI is 6.7% per patient year. Median survival was 7.8 years and death was most commonly due to ischemia. VBNIA are more common in men and typically present in the 6-7th decade. Recurrent CI is more common than hemorrhage risk.