Case

An 87-year-old male patient was referred for evaluation of rapidly progressive sequential painless visual loss, occurring 2 months earlier. The right eye was first affected, and at that time the examination performed by the treating ophthalmologist was within normal limits. One month later, rapid progressive visual loss occurred in the remaining eye. In each eye, visual loss occurred over a few days, with no subsequent changes. The patient had a previous history of prostate adenocarcinoma in remission and mild, treated arterial hypertension. He had an otherwise unremarkable personal medical history, and an ophthalmological examination performed 6 months earlier was normal in both eyes. The patient disclosed several members of the family with blindness: his brother with onset at the age of 30, his sister's son (age of onset was unknown) and his sister's daughter with onset at the age of 3.

On examination, visual acuity was hand movements in the right eye and 20/30 in the left eye. There was no relative afferent pupillary defect and no proptosis and ocular motility was normal. Slit-lamp examination was within normal limits and intraocular pressure was 16 mm Hg in both eyes. Funduscopy disclosed mild optic disc palor, with no pathological excavation in both eyes, but the remainder of the examination was normal. Goldmann visual fields disclosed severe impairment in both eyes, with remaining peripheral islands of vision inferiorly and temporally (figure 1). In the left eye, the visual field loss spared the inferior central area, explaining the residual visual acuity. The remainder of the neurological and general examination was normal.