Abstract
The authors report a rare case of fenestration of the oculomotor nerve by an unruptured internal carotid–posterior communicating (IC–PC) aneurysm. A 71-year-old woman who presented with vertigo was noted to have an unruptured IC–PC artery aneurysm on MRI and CT scans. At aneurysm clipping surgery, it was observed that the aneurysm split the oculomotor nerve. Neurological examination revealed no deficit of oculomotor nerve function before and after aneurysm surgery. Careful dissection of the nerve and the aneurysm is required to preserve oculomotor function.
