Macular Degeneration

Also known as: age-related macular degeneration (ARMD or AMD), age-related maculopathy (ARM), aged macular degeneration, and senile macular degeneration
What is it?
Macular degeneration is a condition in which the part of the eye called the macula becomes damaged. The macula is the central area of the retina. It contains hundreds of nerve endings, packed closely together, and is responsible for the sharpness of the visual image in the center of your field of vision. If the macula is damaged, you no longer have crisp central vision.
Who gets it?
Macular degeneration is a common problem for many people as they get older, both men and women. In fact, it is the most common cause of legal blindness in people over the age of 60. However, this condition is more common in whites than in African Americans, and tends to run in families. People who smoke and eat a diet that is high in saturated fats and low in antioxidants are at greater risk for developing macular degeneration as they age.
What causes it?
Macular degeneration is thought to be caused by hardening and blocking of the arteries (called arteriosclerosis) in the blood vessels that supply the retina. There are two forms of macular degeneration, wet and dry. With wet, also called exudative, macular degeneration, new, fragile blood vessels grow beneath the retina and leak blood and fluid. The leaks form a mound that is often surrounded by small areas of bleeding. This mound eventually shrinks, leaving a scar. The scarring and bleeding can quickly damage the macula. Dry, or atrophic, macular degeneration gradually breaks down the retina's dark-colored cell layer. There is no scarring, blood, or other fluid leakage. Both types of macular degeneration cause a blind spot to form in the center of the person's vision. However, the dry form is more common, and the loss of central vision progresses more slowly and is less severe. Other types of macular degeneration, which are not as common, include cystoid macular degeneration, diabetic macular degeneration, and senile disciform degeneration, also known as Kuhnt-Junius macular degeneration.
What are the symptoms?
The symptoms of macular degeneration may begin with distorted vision in one eye. For example, with the wet form of macular degeneration, straight lines might begin to appear wavy and a central blind spot develops. With the dry form, words may appear blurred or hazy and colors may look dim or gray. The loss of vision can occur slowly or suddenly, but it is always painless. While macular degeneration severely damages the patient's vision, it rarely leads to total blindness. It also has no effect on side (peripheral) vision. Macular degeneration usually affects both eyes, but may affect one eye before the other.
How is it diagnosed?
Macular degeneration is diagnosed according to the types of symptoms described by the patient and an examination of the retina. By putting drops in the eyes to dilate, or widen, the pupils, an eye care specialist (opthamalogist) can see physical changes in the macula sometimes even before symptoms begin. An instrument called an ophthalmoscope magnifies the retina in greater detail. The opthamalogist will also perform a visual field test to check for blank spots in the central vision. Patients who are suspected of having macular degeneration are usually given a central visual field test, called an Amsler grid, to take home with them.
The Amsler grid is printed on a piece of paper and consists of thin lines in a grid formation, with a dot in the center of the page. Patients are told to call the doctor if the lines appear wavy or missing when looking at the dot in the center of the page. The opthamalogist may perform a test called fluorescein angiography to check the retina more closely. With this test, the ophthalmologist injects a special dye into a vein, waits for the dye to reach the retina, then takes photographs of the retina. The photographs show any leaking blood vessels. Patients with macular degeneration are checked frequently for the progression of the disease.
What is the treatment?
There is currently no treatment for the dry form of macular degeneration, but it does progress very slowly. Visual aids, such as large print books, magnifying glasses, and telephones with large print, touch-tone dials are helpful. Wet form macular degeneration can be treated with laser surgery, called laser photocoagulation. Laser photocoagulation is a painless treatment in which a laser beam is aimed through the eye to destroy any new blood vessels and seal off those that are leaking. During the treatment, you may see bright flashes of light. Your vision will remain blurred for a few hours after the procedure and you may feel some discomfort in the eyes. The results of laser photocoagulation may be temporary and will only slow the progression of the disease. Another form of treatment for the wet form of macular degeneration is radiation therapy with either x-rays or a proton beam. Radiation therapy, like laser therapy, damages the abnormally growing blood vessels, but does not harm the nerve cells in the retina. Eating a diet that is rich in the antioxidants beta carotene; vitamins A, C and E; and the minerals selenium and zinc may help prevent or slow the progression of macular degeneration. Good sources of antioxidants include citrus fruits, cauliflower, broccoli, nuts, seeds, orange and yellow vegetables, cherries, blackberries, and blueberries. Other treatments still being studied include drug therapies to slow the growth of blood vessels, subretinal surgery, and photodynamic therapy (PDT). Your doctor can discuss the options with you and recommend the best type of treatment for your condition.
Self-care tips
Because early detection of any disease is extremely important, it's important to have regular eye exams, especially as you get older. You can help lower your risk for developing macular degeneration by not smoking and eating a diet that is rich in green, leafy vegetables and yellow vegetables, and low in saturated fat. Take an antioxidant vitamin supplement, especially vitamin A, to protect your eyes