A 44-year-old woman with a 3-month history of bilateral, painless visual loss in the absence of other symptoms.

A 44-year-old woman presented at the Western Eye Hospital, London, with a 3-month history of gradual, painless, bilateral deterioration of her vision. She had no other ocular symptoms and no previous ocular history. Review of systems was unrevealing, and her medical history was unremarkable: she did not complain of headaches or anosmia, nor was she taking any regular medication. She was of normal body habitus. Family history was non-contributory.