Leber Hereditary Optic Neuropathy (LHON)

Leber hereditary optic neuropathy (LHON) is an inherited optic nerve disease that leads to sudden, painless vision loss during young adult life, most commonly affecting men. It is caused by mutations in the genetic code of the mitochondria, which are small subunits that reside within the cell.

The symptoms of Leber’s Hereditary Optic Neuropathy (LHON) typically present when a person is in their teens or twenties, although in some rarer instances, LHON has been diagnosed in young children and in older adults. 

Affected individuals do not usually present any symptoms until they develop visual blurring or clouding affecting their central vision. These vision problems may begin in one eye or both simultaneously. If one eye is affected, then similar symptoms appear in the other eye on average eight weeks later. 

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