Controversy remains regarding the effectiveness of EC/IC bypass for the prevention of stroke and the authors believe that some studies suggest that a subcategory of patients disabled by transient flow-related symptoms may benefit from surgery. The authors present a 7 1/2 year follow-up analysis of a patient who had undergone an EC/IC bypass from the proximal extracranial carotid to the middle cerebral artery using a 4 mm Gore-Tex prosthesis. Following his death from pulmonary sepsis, the graft was retrieved. Pathological and electron microscopic findings are reviewed.