How Does AMD Affect Vision?

Lylas G. Mogk, MD, a renowned expert on age-related macular degeneration (AMD), founding director of the Visual Rehabilitation and Research Center of Michigan, part of the Henry Ford Health System Eye Care Services, and co-author of Macular Degeneration: The Complete Guide to Saving and Maximizing Your Sight [1], explains:

"Since the macula is the only part of the retina that gives us crystal clear, detailed vision, when it is damaged, details — such as the words on this page or a facial expression — become obscured. Your relative or friend with AMD may not be able to see your eyes, but still makes eye contact because they can see at least the outline of your face and knows where your eyes are. Their eyes also look fine, just like they always did, and their peripheral vision is preserved, so they can walk around with little or no difficulty and may even spot a small dark button dropped on a light rug. This ability to see a lot but not to see the very thing one is looking at is confusing to others, in part because of our habit of thinking of vision as a choice between the two alternatives of sight and blindness. Individuals with AMD are in between; they may not have full sight, but they are certainly not blind and never will be. They have low vision [2], or an even better description is that they are 'hard of seeing,' a term coined by Dr. Lorraine Marchi, director of the National Association for Visually Handicapped [3]. Like the familiar term 'hard of hearing,' it sounds more manageable and it is more accurate.

In addition, about 20% of individuals with vision loss, from any cause, from time to time see life-like images that they know are not really there. This phenomenon is named Charles Bonnet Syndrome [4] (CBS) after the Swiss philosopher who first described it in 1789. The phantom images of CBS are common, pleasant, every day things like flowers or animals or people and the experience is somewhat like looking at a picture or watching a silent movie in color. The images are life-like, in full color and they may move but there is no sound, smell, or contact. It's important to know that CBS is related to vision loss, not to loss of mental capacity."