Age-Related Macular Degeneration (AMD) affects visual abilities. It causes a blank spot (scotoma) in the center of a person’s field of view. That center area is normally the area where vision is the sharpest, so even when a very small blank spot occurs in the center, the vision becomes less clear, even when a person wears eyeglasses that focus vision as well as possible. The larger the center blank spot is, the less clear the vision will be. When the blank spot is only in one eye, the person uses the other eye to see as clearly as possible. When the blank spot is in both eyes, the brain usually uses only the eye with the smallest blank spot when it is trying to see something as sharply as possible.
When AMD affects both eyes, nothing can make a person’s vision clearer. However, if an object or print is too difficult to see, sometimes it helps if the object can be changed so that it appears larger, bolder and stands out from its background.
AMD particularly affects reading ability. Even with a small central blank spot in the better eye, people will usually have difficulty with long reading tasks like reading a newspaper or magazine article, or a chapter in a book. They are reading much more slowly than they were before AMD, and their eyes get tired much more quickly even when the print is enlarged to the best reading size. This occurs even after people learn to use their vision as well as possible either on their own or using lessons provided by a low vision rehabilitation specialist. If the blank spot gets larger, the print will need to be larger for the person to see it. If the print size needs to be larger, reading speed is slower and people’s eyes get tired faster.
Usually, a person with moderate to severe macular degeneration can still see very large, bold print. However they may use their vision to read only when the task is very important and very short, such as a phone number, an address or a price tag. Even tasks like these are read with great effort. Some people who are able to read large print, still prefer to have someone read their mail to them, because it is much easier and faster. They use audio sources, like recorded books or personal assistance, for longer reading tasks.