Macular degeneration or AMD (age-related macular degeneration) is a vision loss disease that is the primary cause of vision loss in Americans who are 65 and over. Macular degeneration occurs when a part of the retina called the macula degrades. This is a problem because the macula creates the primary, clear vision needed for everyday tasks like driving and reading. There are two main types of macular degeneration: dry macular degeneration and wet macular degeneration.
Dry, or non-neovascular macular degeneration occurs when aging macular issues begin to thin out, or pigment begins to build up in the macula. One of the first signs of dry macular degeneration is when drusen, yellowish deposits from deteriorating tissue, appears on the eye, accompanied with gradual loss of central vision.
In one out of 10 cases, dry macular degeneration advances to wet macular degeneration. Wet AMD is much more serious, as neovascularization, or the development of new blood vessels, occurs beneath the retina, leaking blood that permanently damages retinal cells. When retinal cells are lost, blind spots in central vision occur.
Neovascularisaztion can be classic choroidal neovascularization, where clearly delineated new blood vessels develop beneath the retina and severe vision loss occurs. Occult choroidal neovascularization occurs when the blood vessel growth and leakage is not as pronounced and less severe vision loss may result.
There is no cure for macular degeneration and surgery is not a viable option for those experiencing macular degeneration. There are no proven successful treatments for dry macular degeneration other than nutritional supplements. However, in the case of wet macular degeneration, there are many drugs approved by the FDA. A drug called Lucentis has showed some promise in improving the vision of macular degeneration sufferers. This drug and others like it work by attacking the protein (VEGF) that contributes to the development of the abnormal blood vessels. Lucentis treatments involve monthly injections directly into the eye.
Another treatment, called photodynamic therapy (PDT), works on wet macular degeneration sufferers by injecting a drug (Visudyne) into the arm. When the drug enters the retinal blood vessels, the doctor shines a laser into the eye, which activates the drug. It then destroys abnormal blood vessels, reducing the incidence of further damage to the retina.