[A Ruptured Aneurysm at the Origin of a Duplicated Middle Cerebral Artery, Treated by Coil Embolization:A Case Report].

Duplication of the middle cerebral artery(MCA)is an anatomical variant of the MCA, originating from the distal portion of the internal carotid artery(ICA)and supplying blood flow to the tip of the temporal lobe. Cerebral aneurysms rarely develop at the bifurcation of the ICA and the duplicated MCA, but when they do develop, they may result in subarachnoid hemorrhage. We treated a 41-year-old man, who was urgently brought to our hospital because of severe headache. A computed tomography(CT)scan showed subarachnoid hemorrhage due to the rupture of an aneurysm at the origin of the duplicated MCA. The aneurysm was small and projected laterally, and coil embolization was performed employing a balloon catheter. The neck of the aneurysm was not embolized to preserve the origin of the duplicated MCA. The patient had an uneventful postoperative course, and he returned to his usual daily activities. Coil embolization is rapidly developing for treatment of cerebral aneurysms and may be the first-line treatment for duplicated MCA aneurysms. Owing to the relatively small size of such aneurysms, the risk of intraprocedural rupture should be considered, and a carefully performed balloon-assisted procedure is recommended.