Middle cerebral-anterior cerebral-radial artery interposition graft bypass for proximal anterior cerebral artery aneurysm.

A 74-year-old man underwent pterional craniotomy to treat a left proximal anterior cerebral artery (ACA) aneurysm. The orifice of the aneurysm was located at the origin of the proximal segment of the ACA, and the right A(1) segment of ACA was hypoplastic. After failed attempts at neck plasty with fenestrated clips, trapping and bypass were performed. Superficial temporal to left frontopolar artery bypass was performed to secure minimal blood supply. The radial artery (RA) was then harvested, and middle cerebral artery (MCA) to A(1) segment of the ACA bypass was performed using the RA interposition graft. Trapping of the aneurysm was successfully achieved without ischemic event. Intracranial-intracranial bypass has been employed in the treatment of complex cerebral aneurysm in an increasing number of selected patients. The present case shows that MCA-ACA-RA interposition graft bypass is an effective procedure to provide blood supply to the ACA territory if a proximal A(1) lesion requires trapping with incompetent contralateral A(1).