Leber's hereditary optic neuropathy (LHON) or Leber optic atrophy
Is a mitochondrially inherited (transmitted from mother to offspring) degeneration of retinal ganglion cells (RGCs) and their axons that leads to an acute or subacute loss of central vision; this affects predominantly young adult males.
Clinically, there is an acute onset of visual loss, first in one eye, and then a few weeks to months later in the other. This typically evolves to very severe optic atrophy and a permanent decrease of visual acuity. Both eyes become affected either simultaneously or sequentially with a median inter-eye delay of 8 weeks. Rarely only one eye may be affected.