We report a case of a ruptured aneurysm at the site of the left middle cerebral artery (MCA) fenestration. The patient, 54-year-old female, suffered from subarachnoid hemorrhage on July 19, 1995. She was transfered and admitted to our department on the day of onset. On admission she was neurologically intact except for neck stiffness. Cerebral angiography revealed an aneurysm at the right MCA bifurcation and one at the left M1 segment. However, the fenestration at the left M1 segment was not recognized angiographically. The ruptured aneurysm at the proximal end of the fenestration and the right MCA unruptured aneurysm were successfully clipped through the right frontotemporal craniotomy on the day of onset.
Including our case, 29 cases of MCA fenestration with or without cerebral aneurysm had been reported. We discuss the clinical significance of the fenestration of the MCA and the operation through a contralateral approach to the aneurysm at the site of MCA fenestration.
