Temporary flattening of visual evoked potentials in response to suction decompression during internal carotid artery aneurysm clipping: A case presentation

Abstract

The patient was a woman in her fifties who underwent aneurysm clipping for an unruptured right internal carotid artery aneurysm with intraoperative monitoring of visual evoked potentials (VEPs). Although the VEP waveform in the stimulated right eye flattened while the blood flow was blocked with a temporary clip in suction decompression, it was promptly restored upon the release of the blocked blood flow. Only the VEP waveform in the stimulated right eye flattened in this case, which likely reflects malnutrition to the optic nerve caused by a decline in blood flow to the ophthalmic artery that branches from the right internal carotid artery due to suction decompression. VEP monitoring is effective for preventing the postoperative disturbance of visual function; therefore, continuous monitoring of VEP is required by temporarily blocking the blood flow with a temporary clip.