Understanding Macular Degeneration -- Diagnosis and Treatment
How Do I Know if I Have Macular Degeneration?
Your ophthalmologist or optometrist will inspect the macula, the portion of the retina that is responsible for your central vision, as part of a comprehensive eye exam. If macular degeneration is suspected, a special photographic procedure using dye, called fluorescein angiography, may be performed. The test details the pattern of your eye's blood vessels and can detect a variety of abnormalities.
Age-related macular degeneration (AMD) is the foremost cause of vision loss in the U.S., with millions of Americans showing some sign of the disorder. AMD is uncommon in people younger than 55. If you are over 65, macular degeneration may already affect your central vision -- the vision you need for close work like reading and sewing.
AMD occurs in two forms:
Dry: Most common
Wet: Less common, but requires immediate medical attention to preserve central vision
People who develop significant age-related macular degeneration (AMD) typically compensate with large-print publications and magnifying lenses for everyday activities. In addition, evidence suggests that certain vitamins and antioxidants -- vitamins C and E, beta-carotene, and zinc -- may help reduce or delay the risk of severe vision loss. Ask your eye doctor about using nutritional supplements.
Treatment for Dry Macular Degeneration
Dry macular degeneration, the most common form of AMD, cannot be cured at this time, but patients with the condition should continue to remain under an ophthalmologist's care to monitor both eyes. If the one eye is healthy, screening should still continue.
Treatment for Wet Macular Degeneration
A variety of treatments are available for wet AMD. Successful treatment may not restore normal vision, but it will improve sight and prevent central vision loss from worsening. While laser procedures can destroy the abnormal blood vessels, they also damage neighboring retinal tissue.
Medications, such as Eylea, Lucentis, and Macugen, have become the preferred treatment for acute wet macular degeneration, helping to prevent the growth of leaky blood vessels in your eye. Lucentis is given once every month, although some patients may need treatment only once every three months. Macugen is given every six weeks. Eylea is given once every two months after three once-monthly injections.
Laser photocoagulation destroys leaking blood vessels that have grown under the macula and halts the leakage. Laser therapy is helpful for about 10%-20% of people with wet macular degeneration. Some vision loss may occur, because this treatment creates scar tissue that is perceived as blind spots; however, even more vision would be lost if nothing is done at all. Up to half of patients who elect laser therapy may need repeat treatments.
Photodynamic therapy (PDT) uses a different, non-heat-generating laser to treat abnormal blood vessels. Visudyne is injected into the patient's arm and flows through the vessels in the eye. Upon exposure to the laser, a chemical reaction occurs that seals off the leaky vessels. Since the dye is light sensitive, you must stay out of the sun or bright light for several days until the dye has passed from your system. Laser photocoagulation must be done before the abnormal blood vessels cause irreversible damage to the retina. More blood vessels could grow later on, so people who undergo this treatment also need to continue with regular follow-up appointments.