Macular degeneration is the leading cause of severe vision loss in people over age 60. It occurs when the small central portion of the retina, known as the macula, deteriorates. The retina is the light-sensing nerve tissue at the back of the eye. Because the disease develops as a person ages, it is often referred to as age-related macular degeneration (AMD). Although macular degeneration is almost never a totally blinding condition, it can be a source of significant visual disability.
There are two main types of age-related macular degeneration:
Dry form: characterized by the presence of yellow deposits, called drusen, in the macula.
Wet form: characterized by the growth of abnormal blood vessels from the choroid underneath the macula.
Most patients with macular degeneration have the dry form of the disease and will not lose central vision. However, the dry form of macular degeneration can lead to the wet form. Although only about 10% of people with macular degeneration develop the wet form, they make up the majority of those who experience serious vision loss from the disease.
It is very important for people with macular degeneration to monitor their eyesight carefully and see their eye doctor on a regular basis.
Source: Web MD