Bilateral intracranial vertebral artery disease in the New England Medical Center, Posterior Circulation Registry.

Background: Previous studies of patients with bilateral intracranial vertebral artery (ICVA) disease were selective and retrospective.

Methods: We studied risk factors, vascular lesions, symptoms, signs, and outcomes in patients with bilateral ICVA disease among 430 patients in the New England Medical Center Posterior Circulation Registry.

Results: Forty-two patients had bilateral ICVA occlusive disease (18 had bilateral stenosis; 16, unilateral occlusion and contralateral stenosis; and 8, bilateral occlusion).