Acute unilateral visual loss in the elderly due to retrobulbar optic neuropathy.

A 61-year-old man developed fever and a urinary tract infection followed five days later by acute visual loss in the right eye. Funduscopic examination was normal. A retrobulbar optic neuropathy was diagnosed but careful consideration was given to choroidal ischemia as an etiology. A sphenoidal mucocele was found on emergent MRI scan and drained expeditiously, with marked improvement in visual function. The diagnosis of giant cell arteritis should always be entertained when dealing with visual loss in the elderly.