DEAR DOCTOR K:
My ophthalmologist has told me I have “dry” AMD. What is this? What can I expect going forward?
Age-related macular degeneration (AMD) affects the macula, the small part of the retina responsible for sharp, central vision. The retina is the back part of the eye. As light enters your eye, the lens of your eye focuses the light on the retina. The retina then sends signals to the back of your brain. It’s there that your brain translates those signals into vision — the image of the things you are looking at.
People with AMD often develop blurred or distorted vision. They cannot clearly see objects directly in front of them. Eventually they may develop a blind spot in the middle of their field of vision.
In the earliest stages of AMD there often are no warning symptoms. (That’s one reason regular eye exams are important.) If the condition progresses to intermediate AMD, you may begin to notice blurring in the center of your vision. At the advanced stage, the blurred area increases, making it hard to read or even recognize people.
AMD rarely occurs before the age of 55. It then becomes more likely as you get older. One study found it in more than 10 percent of people older than 84.
AMD occurs in two main forms: dry and wet. You mentioned you have the dry form — as do the vast majority of people with AMD. Some cases of dry AMD progress to the more serious wet form of the disease. Wet AMD can cause sudden vision loss.
The less-common AMD is called “wet” because the blood vessels in or underneath the retina start to leak fluid, which causes further damage to the retina.
Currently, the only treatment for dry AMD is vitamin supplementation combined with a well-balanced diet that includes dark green leafy vegetables and several servings of fish per week. Research shows that high doses of antioxidant vitamins and minerals can slow (and sometimes prevent) progression from intermediate to advanced AMD.
You should also monitor your condition by regularly testing yourself at home with an Amsler grid test. You focus your eyes on a central dot on a grid. (The lines near the dot may appear wavy or be missing because of your AMD.) Routinely test each eye and contact your doctor if you notice any changes. Here is an illustration of the Amsler grid test:
The Amsler Grid Test:
Quitting smoking and wearing hats and sunglasses to block the sun’s blue wavelengths — which may promote AMD — may help reduce the severity of the disease.
If you have already lost some vision to AMD, low-vision aids can help. Examples include magnifying glasses, text-to-speech conversion software for your computer, audiobooks, and “talking” watches or alarm clocks.
A patient of mine who was an avid reader developed AMD in her early 70s. Unfortunately, reading became very difficult. For her, audiobooks and text-to-speech conversion of newspaper articles she accessed from electronic Internet subscriptions made a huge difference in her life.