Age-related macular degeneration (AMD) affects the eye’s macula, which allows us to see things clearly. It is not at all painful, usually advances very slowly, and is a leading cause of vision problems in Americans for those over the age of 60. This disease manifests itself in two forms: dry and wet AMD.
The retina, a layer of tissue in the eye, transforms images and light entering the eye into signals that are forwarded to the brain. The macula, which is the small, yellowish portion of the retina, causes our vision to be sharp and detailed. The macula degenerates when the blood vessels and tissue surrounding the macula have been damaged.
Symptoms of AMD
Blurred vision is the most common symptom experienced by those who have dry AMD, and it is confined to their central vision. When this occurs colors may seem faded, and objects may appear to be dim and distorted. Patients often have difficulty in reading or doing other close work, but they usually are able to perform most of their daily activities without difficulty. When the condition grows worse, they may need additional light in order to function, and recognizing faces can become a problem over time.
With wet AMD, straight lines may seem to be distorted and wavy, and a small, dark spot may appear in your central vision that will continue to grow larger. While peripheral vision is not affected, the loss of central vision sometimes happens very quickly, and you should contact your eye doctor immediately if you encounter this problem.
The eye care specialist’s diagnosis will be based on examination of your retina and done according to the symptoms you describe as well. Using eye drops to dilate your pupils, your doctor can evaluate any physical changes taking place in the macula by with an ophthalmoscope, which magnifies the retina. (Eye care professionals also do what is known as a “visual field test” to determine if there are any blank spots in the patient’s central vision.) As a rule, if it appears that you do have AMD, you will be given an Amsler grid, which is a field test of the central vision, to bring home with you.
National Eye Institute, National Institutes of Health
“Facts About Age-related Macular Degeneration”
MedlinePlus: U.S. National Library, National Institutes of Health
Milton S. Hershey Medical Center, Pennsylvania State University