Is Leber's hereditary optic neuropathy a retinal disorder?

We present the case of a 42-year-old man with Leber's hereditary optic neuropathy (LHON) and the 11778 mutation. He had no initial fundal changes, and the pupillary light response was normal at most examinations. The visual acuity declined to less than 0.1 in both eyes. He was unaware of any relatives with poor vision, but his: maternal pedigree was identified and showed five distant relatives with LHON. He enjoyed a very good visual recovery in both eyes over about four years. On the basis of the classical fundal changes and some results of animal studies, previous investigators supposed the retinal nerve fiber layer to be the primary site of neuronal involvement. We suggest that the relatively preserved pupils and possibly also the peculiar delayed recovery support this hypothesis. Prognostic parameters are discussed.