[Two cases of cerebral aneurysm detected after recanalization of the middle cerebral artery].

Two cases of aneurysm incidentally detected after recanalization of middle cerebral artery (MCA) occlusion are reported. Patient 1 was a 62-year-old male with sudden onset of left hemiparesis. We performed emergent intravascular surgery. The initial cerebral angiography revealed occlusion at the M1 portion of the right MCA. After partial recanalization with a microcatheter, carotid angiography revealed a right M1-M2 junction aneurysm. Due to the risk of aneurysmal rupture, the thrombolytic procedure was stopped. Follow up angiography after 1 month revealed complete recanalization of the right MCA and a persistent aneurysm. Patient 2 was a 65-year-old male with left hemiparesis. The initial cerebral angiography revealed occlusion at the M1 portion of the right MCA. After 1 month follow-up cerebral angiography revealed spontaneous recanalization of the right MCA and an incidental aneurysm at the M1-M2 junction. Neck clipping of the aneurysm was performed. When using a microcatheter or microballoon catheter to treat arterial occlusion, surgeons should consider the possibility of a rupture of a hidden aneurysm.