Extracranial surgical procedures in the management of vertebrobasilar insufficiency.

Vertebrobasilar insufficiency is an important syndrome in the spectrum of cerebrovascular disease. Its clinical importance and the frequency of its clinical manifestations are often underestimated. Our experience with a large population of patients having extensive cerebrovascular disease has led us to recognize two classes of vertebrobasilar insufficiency--simple and complex--and, also, to recognize that vertebrobasilar insufficiency is often associated with disease in multiple extracranial vessels. Until recently, direct approaches to the vertebral artery have been underutilized for these patients. In fact, there has been a tendency either to relegate patients with vertebrobasilar disease to medical follow-up or to surgical procedures upon the carotid system. We believe that the resurgence of neurosurgical interest in the vertebrobasilar system is most appropriate. Furthermore, the active interest that neurosurgeons are now taking in developing procedures for managing extracranial vertebral artery problems is in the best interest of patients with cerebrovascular disease. We believe that careful neurosurgical evaluation of patients with simple and complex vertebrobasilar insufficiency will lead to appropriate selection of candidates for vascular reconstruction of the vertebral system. Finally, we believe that vertebral artery to common carotid artery transposition, and its variations, is a procedure that has an important role in the management of cerebrovascular disease.