Simultaneous rupture of two middle cerebral artery aneurysms presented with two aneurysm-associated intracerebral hemorrhages.

Simultaneous rupture of more than one intracranial aneurysm is a rare event and difficult to diagnose. In this case report, we present the case of a patient with a simultaneous rupture of two middle cerebral artery (MCA) aneurysms with two separately localized aneurysm-associated intracerebral hemorrhages (ICH). Initially, the patient presented with headache and neck stiffness as well as progressive decrease of consciousness. Computed tomography (CT) revealed a subarachnoid hemorrhage with a frontal and temporal space-occupying ICH. CT angiography demonstrated two MCA aneurysms located in adjacency to the ICHs, one located at the M1 segment and the other in the bifurcation of the left MCA. Rupture of both aneurysms was confirmed during surgery, and both aneurysms were clipped microsurgically without complications. Although rupture of one aneurysm in patients with multiple aneurysms is the most common event, this case indicates that simultaneous rupture should be kept in mind in patients with multiple aneurysms. In patients with multiple aneurysms, the identification of the ruptured aneurysm(s) is necessary to avoid leaving a ruptured aneurysm untreated.