Leber optic atrophy

Leber’s hereditary optic neuropathy (LHON) or Leber optic atrophy is a maternally inherited form of acute or subacute loss of central vision that may lead to degeneration of retinal ganglion cells (RGCs) and their axons; this affects predominantly young adult males. However, LHON is only transmitted through the mother as it is primarily due to mutations in the mitochondrial (not nuclear) genome and only the egg contributes mitochondria to the embryo. LHON is usually due to one of three pathogenic mitochondrial DNA (mtDNA) point mutations. These mutations affect nucleotide positions 11778, 3460 and 14484, respectively in the ND4, ND1 and ND6 subunit genes of complex I of the oxidative phosphorylation chain in mitochondria. more...

Men cannot pass on the disease to their offspring.

Signs & symptoms

Clinically, there is an acute onset of visual loss, first in one eye, and then a few weeks later in the other. This eventually evolves to very severe optic atrophy and permanent decrease of visual acuity. In the acute stage lasting a few weeks, the affected eye demonstrates an edematous appearance of the nerve fiber layer especially in the arcuate bundles and enlarged or telangectatic and tortuous peripapillary vessels (microangiopathy). These main features are seen on fundus examination, just before or subsequent to the onset of visual loss. Examination reveals decreased visual acuity, loss of color vision and a cecocentral scotoma on visual field examination.

Diagnosis & management

The diagnosis is very difficult and usually requires a neuro-ophthalmological evaluation and/or blood testing for DNA assessment (that is available only in a few laboratories). Hence the incidence is probably much greater than appreciated. The prognosis is almost always that of continued very severe visual loss. There is no accepted treatment for this disease.

Leber’s hereditary optic neuropathy is sometimes confused with Leber's congenital amaurosis, which is a different disease also first described by Theodore Leber in the 19th century.

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