Patient education: Age-related macular degeneration (The Basics)

What is age-related macular degeneration? — Age-related macular degeneration ("AMD") is a disease that causes vision loss. It mostly affects your central vision, so that things in the center look blurry (picture 1). It is most common among people age 65 and older.

There are 2 types of AMD:

●Dry AMD is the most common type. It affects 85 to 90 percent of people with the condition. It causes gradual vision loss.

●Wet AMD is less common. It affects 10 to 15 percent of people with the condition. But vision loss from wet AMD happens more quickly. It can also be more severe and even cause blindness.

Some people start with dry AMD and then develop wet AMD.

What are the symptoms of AMD? — The symptoms are different depending on what type of AMD you have:

●People with dry AMD lose their vision slowly. They might:

•Notice a problem with 1 or both eyes when reading or driving

•Need bright lights or a magnifying glass to see as well as they used to

•Notice spots that seem blurry

●People with wet AMD can have sudden changes in vision. They might:

•Notice problems with 1 eye at first. Later, both eyes usually develop problems.

•See lines that are actually straight as bent or wavy

Should I see a doctor or nurse? — If you notice vision loss or any of the other symptoms listed above, see an eye doctor as soon as possible.

Is there a test for AMD? — Yes. To check for AMD, doctors can use a few different tests:

●Dilated eye exam – For this test, the doctor gives you eye drops to make your pupils open up. Then, they use a special tool to look into the back of your eye, at your retina and the part called the "macula" (figure 1). These are the parts that get damaged by AMD. The doctor also looks for spots called "drusen." These form in the eyes of people who have AMD.

●Fluorescein angiography – This test helps doctors see the blood vessels in the retina. The test is useful because people with wet AMD sometimes develop abnormal blood vessels in the retina.

●Optical coherence tomography ("OCT") – This test creates detailed pictures of the retina. It can show if the retina is damaged.

●Amsler grid – If your doctor thinks that you might have wet AMD, they might have you look at an "Amsler grid" (figure 2). This is a grid made up of straight lines. But to someone with wet AMD, the lines might look wavy or bent.

How is macular degeneration treated? — It depends on the type of AMD.

Both types can be treated with the "AREDS" formula. This is a special combination of vitamins and minerals. For some people, this formula might help to protect the eye from the damage caused by AMD. It is sold without a prescription. But ask your doctor or nurse before you try it. Some vitamins can be harmful if you take them in the wrong amounts. The AREDs formula is the only treatment for dry AMD.

Wet AMD has other treatment options. These work by destroying abnormal blood vessels in the retina, or by preventing new blood vessels from forming there. This helps because much of the damage from wet AMD is caused by these abnormal blood vessels. Treatments include:

●VEGF inhibitors – These are medicines that come in a series of shots that go right into the eye. They help keep new blood vessels from forming. Most people get this treatment.

●Photodynamic therapy – This treatment used to be more common, but now is usually only used for people who did not get better after VEGF inhibitors. For this treatment, you get a shot of a medicine that "sticks to" abnormal blood vessels. This medicine becomes toxic when it is exposed to light. After you get the shot, a doctor or nurse shines a special light into your eye. When the light hits the medicine in the blood vessels in the back of the eye, the medicine destroys the blood vessels.

Can AMD be prevented? — You can lower your chances of getting AMD by not smoking, or by quitting if you already smoke.

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