A 56-year-old man was referred to the Department of Ophthalmology, General Hospital of Kavala, for evaluation of vision loss in his right eye. He had undergone surgical removal of a gastric tumor 15 days previously. Two days before surgery, he complained of slightly blurred vision and mild bulbar pain exacerbated by ocular movement. Immediately after surgery he reported considerable visual impairment. His past ocular history was otherwise unremarkable. Except for the recently diagnosed and treated gastric tumor, he had no other known chronic medical conditions; he did not use scheduled medications and had no known allergies. His family history was remarkable for diabetes mellitus. He worked as a civil servant and did not smoke, drink, or use drugs.