Leber’s hereditary optic neuropathy is maternally transmitted genetic disorder determined by acute or subacute bilateral visual loss the predominantly affects young males, sometimes as young as two years of age.
Leber’s disease is characterized by degeneration of retinal ganglion cells in particular those contributing to the papillomacular bundle, leading to optic atrophy.
Diagnosis is difficult—and somewhat rare—but should be suspected in all patients presenting with a clinical picture of bilateral or painless optic neuritis, irrespective of age. Ophthalmoscopy in acute stage often reveals vascular tortuosity of the central retinal vessels, swelling of the retinal fiber layer and a circumpapillary telangiectatic microangiopathy.
In about twenty percent of Leber’s Hereditary Optic Neuropathy cases, the optic disc looks normal at presentation. Within 6 weeks optic nerve pallor becomes apparent, initially more marked temporally due to early axonal loss within the papillomacular bundle. Electrophysiological characteristics of LHON patients include marked reduction in N95 component of the pattern electroretinogram and markedly abnormal to no detectable P100 component of the pattern visual evoked potentials.
Though treatment is generally ineffective a randomized placebo-controlled study showed that idebenone, an analog of CoQ10, has some statically significant effect of improving visual function in patients with Leber’s Hereditary Optic Neuropathy.