Macular Degeneration is a name given to a collection of eye diseases that results in loss of central vision (peripheral vision is not affected). However, it can also cause blindness. Most cases of macular degeneration are isolated, individual occurrences, mostly in people over age 60. These types are called Age Related Macular Degeneration (ARMD).
Much less common are several hereditary forms of macular degeneration, which usually affect children or teen-agers. Collectively, these are called Juvenile Macular Degeneration and include Best's Disease, Stargardt's Disease, Sorsby's Disease and some others. Overall, over 12 million people suffer from this condition.
The Retina
The retina is neurological tissue that contains rods and cones (a photosensitive array of cells). When the retina receives light, it converts the light to electrical signals for transmission to the brain via the optic nerve. The brain then processes and interprets these signals.
The Macula
The most concentrated collection of photosensitive cells in the retina, including those that enable critical color and fine detail vision, are found in the Bulls-Eye center zone in an area called the macula.
Macular degeneration
Macular degeneration causes sight-sensing cells in the macular zone of the retina to malfunction or lose function, resulting in debilitating loss of vital central or detail vision. Because the brain cleverly learns to compensate and fill in the missing part of the picture in early cases with spotty macular cell damage or dysfunction, most people only present to their ophthalmologist when disease is fairly advanced.
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