Lebers Hereditary Optic Neuropathy (LHON) symptoms usually begin as sudden, painless loss of central vision. The classic pattern is for one eye to suddenly lose central vision, then within weeks to months the other eye also loses central vision. Each eye quickly gets worse than 20/200 (the threshold for legal blindness) as the central scotoma (blurry blind spot) rapidly expands over about 6-8 months. Severe vision loss in both eyes is the usual outcome. In rare cases the interval between eyes can be years, and in some cases both eyes onset at the same time. Reading standard-sized text, driving, and recognizing faces become impossible.
The affected person usually retains some amount of peripheral vision, varying significantly by individual. This allows the person to walk around independently, though in many cases a white cane or guide dog is required for safe mobility. Since the LHON affected individual often does not “look blind,” those around them struggle to understand their situation and don’t realize how profound their vision loss is. Color vision usually becomes impaired also, usually with red lost first, and bright royal blue the most visible.
The first video below was filmed at the 2015 LHON Conference and addresses the most commonly-asked medical questions about LHON with three of the world’s LHON leaders [Dr. Patrick Yu-Wai-Man (UK), Dr. Valerio Carelli (Italy), Dr. Alfredo Sadun (USA)]. Next is an LHON overview at the 2017 LHON Conference with Dr. Nancy Newman, another global LHON expert.