Macular degeneration, << MAK yuh luhr dih jehn uh RAY shuhn, >> often called MD, is a serious disorder of the eye that can result in vision loss. The macula is a circular area at the center of the retina, the tissue lining the inside of the back of the eye. The macula is responsible for sharp central vision. Macular degeneration results when the cells of the macula break down. The chances of developing MD increase with age. Such age-related macular degeneration (ARMD or AMD) is the leading cause of vision loss in people over 60 years of age. Scientists have also identified a specific gene related to the development of MD in some people. However, MD does not cause total blindness, and people retain peripheral (side) vision.
One form of MD called atrophic, or dry, macular degeneration develops slowly. It is characterized by a gradual deterioration of the retina cells and vision loss. Another form, called exudative, or wet, macular degeneration, can progress rapidly. In this form, blood vessels develop and grow beneath the retina. The fragile vessels bleed, leading to the formation of scar tissue. The scar tissue blocks the macula, causing vision loss.
There is no cure for MD, but vitamin therapy can help slow the progression of the disorder. Physicians may use laser surgery to seal leaking blood vessels to delay the progression of wet MD. A drug called ranibizumab can reverse some of the vision loss caused by wet MD. Magnification aids and bright lighting can help people deal with the vision loss caused by MD.
See also Blindness (Diseases) ; Eye (Diseases of the retina) .