Age-related macular degeneration (ARMD) is a progressive disease that causes loss of central vision. The dry form causes blurriness that may be mild or severe. During the wet form of ARED abnormal blood vessels grow that can leak--resulting in severe vision loss. Treatments include holistic approaches, laser surgery, photodynamic therapy, eye injections, home modifications such as special lighting, adaptive devices such as magnifiers and training in eccentric viewing techniques.
Holistic Treatments
Studies have suggested that a diet rich in green leafy vegetables may not only lower the risk of developing ARMD, but also slow its progression. Herbs that are thought to slow vision loss during the early stage of ARMD include bilberry extract and ginkgo biloba extract. Antioxidants are nutrients such as vitamins, minerals and enzymes that counteract the damage of the oxidation process in animal tissue. Blueberries are one source of antioxidants as well as other berries. Doctors may recommend that patients take a special high-dose formula of antioxidants, zinc and copper during the intermediate stage of ARMD to reduce the risk of developing advanced stage ARMD. The National Eye Institute's Age-Related Eye Disease Study (AREDS) found that this formula slows down the progression of the disease. Interestingly, the formula was not shown to be effective during the early stage of the disease. The AREDS antioxidant formula includes vitamin C, E, A, and zinc and copper.
Medical Interventions
Patients may be treated with laser surgery or photodynamic therapy to prevent or slow the rate of vision loss. However, neither treatment will restore lost vision. Laser surgery destroys leaky blood vessels that interfere with vision. However, there are risks that new blood vessels will develop after the surgery or that treatment will destroy healthy tissue.
Photodynamic therapy involves using light to activate a drug that destroys the new blood vessels. The results from this therapy may be temporary, requiring it to be repeated. A more recent medical intervention for the wet form of ARMD involves injecting a drug into the eye that blocks the effects of growth factors that promote new abnormal blood vessels. This treatment often helps to slow vision loss and may even improve vision in some cases.
Home Modifications and Adaptive Devices
Low vision occupational therapists work with patients to adapt the home to increase function and independence. Home modifications may include improved lighting such as special low vision lamps or setting up a lamp to shine on the reading material creating color contrast. Other modifications include decreasing glare with curtains or using tactile bumps to feel oven and stove settings. Special adaptive devices such as a needle threading machine, talking clock, large print playing cards, strong magnifiers or electronic devices that enlarge reading materials can enable the person with advanced ARMD to read and perform daily living activities.
Eccentric Viewing Techniques
Although patients with ARMD lose their central vision, their peripheral vision remains in tact. They can make best use of the remaining vision by learning how to view from the side using "eccentric viewing." This involves looking above, below, left or right of a visual target such as someone's face-rather than looking directly at the person. Occupational therapists train patients to first use eccentric vision to find objects in the environment. Next a patient can learn how to use eccentric viewing to read by looking either above, below or to the side of the target word. Therapy to improve reading skills also includes providing proper lighting, possible use of a magnifier and a book stand to stabilize reading material.
References
- "Prescription for Natural Cures"; James F. Balch, M.D.; 2004
- "Low Vision Rehabilitation"; Mitchell Scheiman; 2007
- "Age-Related Macular Degeneration; What You Should Know"; National Eye Institute; 2003
- "Foundations of Low Vision: Clinical and Functional Perspectives"; Anne L. Corn and Alan J. Koenig; 2004
- "Coping with Vision Loss"; Bill Chapman; 2001
