Falsely nonrecordable flash visual evoked cortical potentials in a diabetic eye with severe vitreous hemorrhage.

Abstract

The examination of visual evoked cortical potentials (VECPs) prior to vitrectomy has been proposed for selection of patients with good chances for a favorable outcome following surgery. A missing single flash VECP has been considered a contraindication for further surgical treatment. A 64-year-old woman with proliferative diabetic retinopathy suffered from an intensive vitreous hemorrhage in one eye. Preoperatively, the flash VECP was nonrecordable. Intraoperatively, a dense vitreous hemorrhage and retrohyaloidal blood was found. The retina was attached. Postoperatively, the flash VECP was similar in both eyes with normal latencies. The visual acuity improved from light perception to 0.05. Severe vitreous hemorrhage may interfere with preoperative VECP recordings. A nonrecordable VECP has to be judged cautiously so as to prevent false-negative responses in eyes that could regain vision following vitrectomy and removal of the hemorrhage.