Age can cause a wide variety of problems in the central part of the retina which is called the macula. Years ago all of these problems were lumped into one term called macular degeneration. This is the leading cause for vision loss after age 65 and typically results in a blind spot in the center of vision. Today, we have sophisticated ways to diagnose and classify these problems with the hopes of treating them.
The delicate nerve cells in the back of the eye are arranged much like a dartboard. The macula is similar to a “bull’s eye,” the very center of the retinal tissue. It is home to our finest eyesight. Because of the immense amount of work done by these cells over the course of our lives, they tend to break down and malfunction. Sometimes this degeneration allows abnormal blood vessels to grow which may suddenly cause some distortions in vision.
Many people, usually after age 65, develop a “wearing out” or degeneration of the macula as part of the aging process. It is unknown why some people acquire these changes and others do not. There appears to be an increased risk of macular degeneration with increasing age, in cigarette smokers, and in those who have other family members affected by this disease. Currently, there are 15 million people in the United States affected by age-related macular degeneration with over 1.6 million having the more severe wet type.
The fine area of central vision is most affected. This is the part of the eye we use to read, drive, or thread a needle. Patients with severe macular degeneration rarely lose peripheral vision.
Dry Macular Degeneration (Dry AMD)
There are two basic types of age-related macular degeneration. The least severe being the dry type. The hallmark clinical finding of dry macular degeneration consists of small aging spots or drusen.
Wet Macular Degeneration (Wet AMD)
New blood vessels (choroidal neovascularization referred to as CNV) grow beneath the macula in the more severe wet form. These vessels cause the overlying macula to swell with fluid and blood which often causes permanent central vision loss.