Macular degeneration
is a degenerative disease characterized by the breakdown or damage to a portion of the retina (the light sensitive layer of the eye) known as the macula. Age-related macular degeneration (AMD) is the most common type of macular degeneration, affecting approximately 1.7 million older Americans. It is the leading cause of visual impairment for people age 75 and older and the predominant cause of new cases of visual impairment among those over age 65.
Nearly everyone experiences changes in their vision as they grow older. For example, you may need more light to see, or it may become harder to tell the difference between colors. You may also have difficulty focusing on things that are close to you or adjusting to glare or darkness.
AMD, on the other hand, is a retinal eye disease that causes progressive loss of central vision, leaving only peripheral, or side, vision intact. AMD affects the macula, the central part of the retina, which is located in the back of the eye and responsible for sharp central vision. There are two types of macular degeneration:
Dry AMD:
This affects about 90% of those with the disease. Gradually, the light sensitive cells in the macula break down. Dry AMD often occurs in just one eye at first. You may or may not get the disease later in the other eye. Symptoms of dry AMD include:
- Words in books, magazines, and newspapers appear blurry
- Dark or empty spaces block the center of your vision
There are currently no established treatment options for dry AMD.
Wet AMD:
Although only 10% of all people with AMD have this type, it accounts for 90% of all severe vision loss from the disease. It occurs when new blood vessels behind the retina start to grow in the macular region. Onset and progression are rapid. Symptoms of wet AMD include:
- Straight objects in your field of vision, such as telephone poles, the sides of buildings, and streetlight posts appear wavy or otherwise distorted
- Dark or empty spaces block the center of your vision
Treatments for wet AMD include laser photocoagulation, which is a surgical procedure involving a laser to seal and halt or slow the progression of abnormal blood vessels and photodynamic therapy (PDT); or a therapy that uses a nonthermal (cold) laser with an intravenous light-sensitive drug to destroy the abnormal blood vessels.
If you notice changes in your vision, you should contact your eye doctor immediately. The earlier AMD is diagnosed, the better the chances of preventing vision loss.
Although scientists don’t yet know what causes AMD or how to fully prevent it, there are steps you can take to lower your chances of developing AMD and delay its progression:
- Make regular exams a priority. Early detection of AMD through regular eye exams is critical. The American Academy of Ophthalmology recommends that individuals age 40–64 with no AMD symptoms have eye exams every 2-4 years; after age 65, eye exams should occur every 1-2 years (or more frequently if recommended by your eye care specialist). Remember that people with certain eye and medical conditions require eye examinations much more frequently.
-
Control your risk factors. Quit smoking. Manage
high blood cholesterol
and
blood pressure
. Eat a healthful diet low in saturated fat and rich in fruits and vegetables. These contain lutein, which has shown promise in one small clinical trial for fighting macular degeneration and zeaxanthin which is hypothesized to be protective.
Also, the results of one large clinical trial, called the Age-Related Eye Disease Study, indicated that somewhat high dosages of zinc, with or without the antioxidant vitamins
C
and
E
, and
beta-carotene
, might help to significantly reduce the risk of developing advanced stages of AMD for people who already have moderate AMD. But, researchers could not determine whether the effect would last over a long period of time or with different doses of these or other supplements. You can also protect your eyes from damage by UV light by wearing brimmed hats and UV-protected sunglasses.
If you have AMD, you can continue to lead an active and independent life. Even if you have experienced some vision loss, normal use of your eyes (watching TV, reading, etc.) will not cause further damage to your vision.
Low-vision aids (special lenses or electronic systems that make images appear larger) are available to help you make the most of your remaining vision. Your eye care professional can prescribe them or refer you to a low-vision specialist. In addition, groups and agencies that offer information about counseling, training, and other special services are available. You may also want to contact a nearby school of medicine or optometry as well as a local agency devoted to helping the visually impaired.
Lastly, by staying well-informed, you can learn what problems may develop with your vision, how those problems can be detected, and what steps you can take to save your remaining sight.
