What is age-related macular degeneration?

Monday, October 4, 2010; 5:56 PM

Age-related macular degeneration is the leading cause of vision loss in adults older than 50.

AMD destroys the light-sensitive cells in the macula, the part of the retina that provides sharp vision of things directly in front of the face. People with AMD may see a blurred spot in the center of their field of vision, and they may eventually not be able to recognize faces, drive a car or do close activities such as reading.

AMD almost always begins in what is called a dry form. The deterioration of the macula progresses slowly, often with no symptoms in the early stages; only a comprehensive dilated eye exam can detect dry AMD.

Once dry AMD reaches the advanced stage, nothing can prevent vision loss. Taking a high-dose formulation of antioxidants and zinc has been shown to delay and possibly prevent intermediate AMD from progressing to the advanced stage.

About 10 percent of dry AMD sufferers develop the wet form, which is considered more severe. New blood vessels beneath the macula leak blood and fluid, damaging the macula quickly.

As people age, their risk for AMD increases, and health experts recommend people have an annual dilated eye exam. Other risk factors include: smoking, race and family history. Research has found Caucasians have a particularly high risk for AMD.

Health experts suggest that certain lifestyle choices may help reduce an individual's risk of developing AMD; they recommend that people exercise, avoid smoking, maintain normal blood pressure and cholesterol levels, and eat a diet rich in fish and vegetables.

For more about AMD, contact the Washington National Eye Center, the Wilmer Eye Institute at Johns Hopkins, the Foundation Fighting Blindness in Columbia and the American Health Assistance Foundation in Clarksburg.

- National Eye Institute

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