The right eye of a 66-year-old man was operated with vitrectomy and peeling of an epiretinal membrane. Perioperatively, the eye was filled with 20% SF6 gas to tamponade retinal breaks. Five days later the patient underwent prostatectomy under general anesthesia using nitrous oxide. Postoperatively the eye had no light perception as a result of ischemic retinopathy. The movement of nitrous oxide into gas-containing spaces in the body has been known for a long time. The use of nitrous oxide in patients with intravitreal gas will elevate the intraocular pressure with risk for closure of the central retinal artery. The present case report highlights the problems that can occur when preoperative assessment is carried out a long time before surgery.