Revascularization and aneurysm surgery: current status.

Unclippable intracranial aneurysms are most effectively treated by hunterian ligation; however, the attendant risk of cerebral ischemia is significant. Many techniques have been used in an attempt to predict the safety of proximal vessel occlusion. Unfortunately, there is none that is risk-free and highly successful. A combination of stump pressure and cerebral blood flow measurements has been shown to be the most accurate in the acute assessment. In addition, recent studies have demonstrated that the long term risk of carotid ligation is significant. Extracranial-intracranial bypass grafting (EC-IC) has been shown to improve the safety of parent vessel ligation and is a low risk procedure. Whenever hunterian ligation is planned for the treatment of an intracranial aneurysm, EC-IC should be strongly considered.