Advanced macular degeneration (AMD) affects more than 1.75 million Americans and is the leading cause of blindness in people older than age 65, All About Vision reports. There are two types of macular degeneration, dry and wet, with dry being the milder and more common form affecting 85 to 90 percent of people with the condition. The U.S. Food and Drug Administration-approved treatments for AMD are designed to prevent the abnormal blood vessels that cause wet AMD from forming in the macula.
Anti-VEGF Intravitreal Injections
Anti-VEGFs, or vascular endothelial growth factors, are medications that block the release of proteins called VEGFs. VEGFs stimulate growth of new blood vessels. FDA approved anti- VEGF medications include Lucentis, manufactured by Genentech and Macugen, manufactured by Eyetech. Both medications are injected intravitreally into the white part of the eye, the sclera, using a very small needle. Vision improves in around one-third of patients receiving anti-VEGF treatment, All About Vision reports. Avastin, an anti-VEGF drug developed for use in colon cancer also manufactured by Genentech, is not FDA-approved for use in the eye but is widely used because it's less expensive than Lucentis.
Photodynamic Therapy
Photodynamic therapy, or PDT, was FDA-approved in 2000 to treat wet AMD. Verteporfin, a drug that is activated by light, is infused into the body, followed by an 83 second laser treatment aimed at the abnormal blood vessels. The light, which is a cold laser rather than a thermal laser which would destroy the part of the macula containing the abnormal vessels, activates the medication in the blood vessels, causing a chemical reaction that seals off the leaking vessels. PDT was the treatment of choice for wet AMD until the anti-VEGF medications were introduced starting in 2006. PDT stabilizes vision in some cases but doesn't restore lost vision, the Illinois Eye and Ear Infirmary reports in the Aging Eye Digest.
Thermal Laser
Thermal, or hot laser, an FDA-approved treatment for use in wet AMD, is rarely used today. Thermal laser is still used occasionally if the abnormal blood vessels don't affect the fovea, the central point of vision on the macula, according to the Merck Manual. Thermal laser has been largely replaced by anti-VEGF treatment or PDT because it causes scarring on the retina, All About Vision explains.
