Leber's Hereditary Optic Neuropathy is a rare condition which can cause loss of central vision. It usually affects men, most commonly in the late twenties or early thirties, but the symptoms can happen at any age, to men or women.
Usually Leber's affects one eye first, so central vision is lost in that eye over a period of a few weeks. One or two months later, the second eye is affected in the same way. The time when someone is losing their eyesight is often called the 'acute' period. After a few more weeks, the eyesight stops getting worse.
Although that describes the most common pattern for Leber's, it can also affect someone very suddenly, or can affect them more gradually over a period of years.
Leber's is linked to a number of genes, all in the DNA of structures called mitochondria. These provide energy to the cells of the body. We believe that the particlular gene changes linked to Leber's lower the amount of energy available to the cells of the optic nerve and retina. These cells are damaged and can even die because of this lack of energy. The damage to the optic nerve and retina is what causes the symptoms of Leber's.
