Bypass Revascularization Applied to the Posterior Cerebral Artery

Abstract

The application of bypass procedures to the posterior cerebral artery (PCA) in combination with proximal clipping or trapping is a useful option for the treatment of complex posterior circulation aneurysms, especially those of the PCA. Because of its course around the midbrain through various cisterns, different approaches are required to access the PCA. The presented study analyzes a retrospective case series of bypass procedures to the PCA to investigate the relevant treatment strategies and their outcomes. Seven patients with bypass procedures to the PCA bypass were analyzed. The location of the aneurysms, approaches, site of anastomosis, bypass patency, pre- and postoperative modified Rankin Scale scores, and transient and permanent morbidity were assessed. Analyzed patients were treated for intracranial aneurysm located on the P2 (n= 3) or P3 (n= 2) of the PCA, bilateral vertebral artery dissecting aneurysm (n= 1) or internal carotid artery-posterior communicating artery aneurysm (n= 1). The following approaches were used: anterior temporal approach (n= 2), anterior temporal approach combined with subtemporal approach (n= 2), combined transpetrosal approach (n= 1), posterior interhemispheric approach (n= 1), and posterior interhemispheric approach with subtemporal approach (n= 1). All bypasses were patent. Permanent morbidity occurred in 2 patients via cognitive dysfunction (n= 1) and hemiparesis (n= 1). Bypass revascularization of the PCA territory is effective for the treatment of complex vascular lesions affecting the posterior circulation. To address the various surgical segments of the PCA, different approaches are required. Combined approaches allow access to the PCA proximal and distal from the lesion.