Natural History of Visual Loss in Lhon and Doa

The past two decades have witnessed remarkable advances in our understanding of the clinical presentation, genetics and even the pathophysiology of the hereditary optic neuropathies, specifically Leber hereditary optic neuropathy (LHON) and dominant optic atrophy (DOA)1-4. We now know that most of the hereditary optic neuropathies, including LHON and DOA, have a pathophysiology reflecting a final common pathway in mitochondrial dysfunction, despite their genetic origin in two different genomes (LHON a result of point mutations in the mitochondrial DNA, and DOA a consequence of mutations in nuclear chromosomes). However, investigations into potential therapies for these and other mitochondrial disorders are still in their nascency. Before reviewing the evidence currently available on the treatment of these disorders, it is important to discuss the natural history of visual loss in these clinical settings, specifically the prognosis for spontaneous visual recovery.