Noninvasive Detection of a Ruptured Aneurysm at a Basilar Artery Fenestration with Submillimeter Multisection CT Angiography

Summary: The criterion standard for the detection of in-tracranial aneurysms is digital subtraction angiography. MR imaging and CT provide good accuracy in the evalua-tion of brain arteries and aneurysms. We herein report a case of a ruptured aneurysm at a basilar artery fenestra-tion. The diagnosis was assessed with 16-row multisection CT angiography and was confirmed by using digital sub-traction angiography. The patient was successfully treated with coil placement. A fenestration or a segmental duplication of the basilar artery, previously reported exclusively as an anatomic variation, owes its clinical interest to the possible association with aneurysms localized at the junctions of the fenestrated segments (1). The fenes-tration is frequently located in the proximal basila