Researchers eye earliest triggers of age-related macular degeneration

Age-related macular degeneration is the leading cause of blindness for Americans over 60 years of age. It affects more than 14 million people. But how it attacks the macula, the center of the retina, is a controversial question. The macula is where the cones — the color and light sensing cells of the eye — reside. Macular degeneration involves the decreased functioning of the cones. Some researchers have long thought that the demise of the cones involves the inability of the cones to regenerate a necessary pigment. But a more complicated picture is emerging because of the work of Harvard researchers. Schepens Eye Research Institute’s Ann Elsner, Stephen Burns, and John Weiter have been studying people with early stages of disease and found that the cones’ ability to collect light is impaired even when their ability to regenerate pigment is about normal. The researchers, whose report appears in the January 2002 Journal of the Optical Society of America, suggest that the initial problem lies not in the cones’ ability to recycle their light-processing pigment but in their ability to physically capture light in the first place. The findings could be used to prevent future generations from suffering macular degeneration’s damage.