A pupil-sparing oculomotor palsy from a contralateral giant intracavernous carotid aneurysm.

A patient presenting with a left pupil-sparing oculomotor palsy and periorbital pain was subsequently found to have a giant saccular aneurysm of the right internal carotid artery within the cavernous sinus. The aneurysm was of the contralateral artery compared to the side of all presenting neuro-ophthalmic signs and symptoms. Diagnosis was achieved by bilateral carotid arteriography and surgical treatment with a Crutchfield arterial clamp and bypass graft has returned the patient essentially to normalcy.