Major Causes of Vision Loss
by Dr. Arghavan Almony and Dr. Anna Fakadej
Vision is one of our most important senses, providing an estimated 80 percent of the information we take in from the outside world. If possible, we want to preserve our vision throughout our lives. The three major causes of vision loss as we age are cataracts, macular degeneration, and glaucoma.
Cataracts develop when the lens of our eye loses the ability to transmit images from the outside world to our retinas. Our lenses are made of proteins, and as these proteins change over time, their ability to allow light through decreases. Sunlight, especially the ultraviolet (UV) portion, contributes to these lens changes. Vision loss from cataracts is usually slow. Images are not as clear, colors are not as bright, and seeing at night is more difficult. The good news about cataracts is that they are a readily treatable form of decreased vision. With new surgical techniques and the latest intraocular implants, skilled surgeons often return vision to the way it was years earlier.
Age-related macular degeneration (AMD) affects the central vision and can impair daily activities such as reading and driving. Vision loss may be mild, moderate, or severe, and typically occurs slowly in the “dry” form of AMD. This form may also cause small blank spots in our central vision. A small chart, called an Amsler grid, can be used to monitor potential changes in vision, and a special vitamin formulation can slow the progression of “dry” AMD. When new blood vessels grow under areas of “dry” AMD, blood and serum can leak out, resulting in the “wet” form of AMD. If left untreated, “wet” AMD can cause significant vision loss. In the United States, as many as 11 million people are affected by macular degeneration, and of those, more than 1 million people have the “wet” form of macular degeneration.
Glaucoma is actually a group of diseases that cause damage to the optic nerve, the nerve which carries visual information from the eye to the brain. This damage initially results in loss of peripheral vision, and ultimately blindness, if untreated. Intraocular pressure (IOP), otherwise known as pressure inside the eye, is usually increased in glaucoma, and is a major risk factor. Other risk factors include ethnicity, age, family history, previous eye injury, and long-term corticosteroid use. Modern treatment for glaucoma is very effective, including eye drops, laser treatments, and eye surgery.
To look for these and other potential eye diseases, have your eyes examined yearly by your eye doctor.