March 7, 2002
Macular degeneration: An age-related cause of lost sight
Age-related macular degeneration, or AMD, is a change in the central part of the retina, the thin film coating the back of the eye. While AMD is the leading cause of legally defined blindness in the Western world, Dr. David Saperstein, assistant professor in the UW Department of Ophthalmology, says a person with AMD will never go totally blind. “He or she will always have peripheral vision. It’s very rare that an AMD patient needs a guide dog or a cane,” Saperstein says. “They can usually dress themselves and navigate around their homes and neighborhoods, but they do have trouble with reading, driving, recognizing faces and shopping.” AMD is usually spotted during a routine eye examination, when an ophthalmologist or optometrist sees yellow spots called drusen on the surface of the retina. As time passes, three things can happen. “Either the condition will remain primarily unchanged, the retina can deteriorate over several years in what is called the dry form of the disease, or the patient could develop abnormal blood vessels growing underneath the retina,” Saperstein says. “That’s the wet form of AMD.” Current treatment for AMD includes photodynamic therapy, using a laser beam to destroy some of the abnormal blood vessels threatening the patient’s vision. Saperstein and other UW researchers have been seeking ways of improving this approach that was approved by the U.S. Food and Drug Administration only two years ago. “It is to date the best tool we have for treating AMD, but it’s not perfect,” Saperstein says. “More recently, a large study by the National Eye Institute has been examining vitamin and antioxidant therapy for AMD patients. The results show that patients who were taking antioxidants and who had moderate to severe AMD had a decrease in vision loss and slowing of the disease compared to patients taking only vitamins.” Saperstein points out that the study does not prove that taking vitamins and antioxidants will prevent AMD, but it is hopeful for AMD patients. “If you’re not spending the rent money on supplements and vitamins, and you have no other health problems that the vitamins might interfere with, I’d say go ahead and take them in moderate quantities, as directed on the container,” Saperstein says. AMD has some controllable risk factors. While the disease is more common in older, fair-skinned adults, not smoking and protecting your eyes from sunlight by wearing hats and sunglasses help reduce the odds against you. While the outlook for AMD sufferers is gradually improving, Saperstein says it will be getting even better soon. “There is a big push by the National Eye Institute and many pharmaceutical houses to understand the basis of AMD and develop better treatments for it,” Saperstein says. “There are several drugs and therapies in various stages of development, as well as efforts to make photodynamic therapy better. Beyond that, we’re also working on ways to prevent AMD – that’s the real brass ring.”
