ANEURYSM FORMATION AND RUPTURE AT THE SITE OF ANASTOMOSIS FOLLOWING BYPASS-SURGERY

Four years after undergoing a superficial temporal artery-middle cereb ral artery bypass procedure, this patient presented with a ruptured an eurysm at the anastomosis site. The ruptured aneurysm caused subarachn oid and intracerebral hemorrhages and was treated by surgically clippi ng its neck. Characteristics of the aneurysm included: 1) a relatively large size (8 x 6 x 6 mm); 2) a thickened wall; 3) a location apart f rom the suture line; 4) a projection in a direction consistent with he modynamic stress; and 5) a time interval from bypass surgery to ruptur e that lasted 4 years. These features, along with the well-known fact that hemodynamic stress can cause aneurysms, led the authors to believ e that this aneurysm was a true one. The authors present a case of thi s unusual complication following bypass surgery and provide a brief re view of the literature.