What it is
The macula is the light-sensitive tissue at the back of the eye, which is part of the retina. It controls sharp, straight-ahead (central) vision. Age-related macular degeneration (AMD) is an eye disease that blurs central vision (see images below). It happens when aging causes damage to the macula.
AMD does not cause complete blindness, just at the center point of the visual field. Losing central vision, however, can make it harder to see faces, read, drive, or do other close-up tasks like cooking or fixing things around the house.
AMD happens very slowly in some people and faster in others. In early AMD, vision loss may go unnoticed for a long time. This is one reason why your loved one should get regular eye exams.
Normal Vision (without AMD)
Vision with Late Age-Related Macular Degeneration (AMD)
What causes it
The cause of AMD is unknown but there are many risk factors associated with its development.
Older age
Genetics (family history)
Smoking
Diet (high in saturated fat)
High cholesterol
High blood pressure
Race (Non-Hispanic Whites are most affected)
Gender (women live longer than men, so AMD diagnosis is higher in women)
Two types of AMD
WET
Wet AMD, also called advanced neovascular AMD, is a less common type of late AMD that usually causes faster vision loss, and can lead to severe and permanent vision loss. It develops when abnormal blood vessels grow in the back of the eye and damage the macula. These leak blood or fluid that leads to scarring of the macula and rapid loss of central vision. Any stage of dry AMD (see below) can turn into wet AMD, but wet AMD is always late stage. The good news is that there are treatment options available for wet AMD, such as injections and laser treatments.
DRY
Dry AMD, also called atrophic AMD, is the most common type. It is a gradual deterioration (thinning) of the macula as the retinal cells die off and are not renewed. Dry AMD happens in 3 stages: early, intermediate, and late. It usually progresses slowly over several years. There’s no treatment for late dry AMD, though your loved one can make the most of their remaining vision. Also, if they develop late dry AMD in only one eye, steps can be taken to protect the other eye.
Early Stages of AMD
Later Stages of AMD
Symptoms
The symptoms of AMD depend on the type and the stage. AMD is a progressive disease (symptoms get worse over time).
Early dry AMD doesn’t cause any symptoms.
Intermediate dry AMD may still have no symptoms, or subtle symptoms that include mild central vision blurriness or trouble seeing in low lighting.
With late AMD (wet or dry type), straight lines start to look wavy or crooked.* There may also be a blurry area at or near the center of the visual field. Over time, this blurry area may get bigger or become blank spots. Colors may also seem less bright than before, and there may be increased difficulty seeing in low lighting.
*Note that straight lines looking wavy is a warning sign for late AMD. If your loved one has this symptom, take them to an optometrist or ophthalmologist right away.
Is AMD the same as low vision?
AMD is not the same as low vision, and while AMD can cause low vision, the two don't always occur together. Other causes of low vision include glaucoma, cataracts, and diabetes.
Low vision is a vision problem that cannot be corrected with conventional eyeglasses* or contact lenses, or fixed with medical or surgical treatments. Low vision makes it hard to do everyday activities.
*Specialized filter lenses can sometimes help.
What can I do to help?
Encourage your loved one to share their complete family history, including eye complications, with their eye care provider.
Ensure that your loved one is getting annual eye exams, even if they feel they have no problems.
Ensure that your loved one is getting annual wellness check-ups (physicals) with blood work that includes a cholesterol panel.
Help them find assistance to quit smoking. Talk to their provider.
Help them make good food choices (especially increasing green and leafy vegetables).
Help them get moving and get active.
Talk with their provider about how to get a daily intake of Vitamin C, Vitamin E, Beta-carotene, Zinc, and Copper.
Age-related disease studies found that getting combinations of these vitamins and minerals every day may slow the progression of AMD from the early or middle stages to the later stages, and reduce the risk of late AMD by 25%.