Age-related Macular Degeneration (AMD)May 17, 2017
Macular Degeneration is the leading cause of vision loss, affecting more than 10 million Americans – more than cataracts and glaucoma combined. Our Eye Center is proud to have Dr. Edward Fitzpatrick, a retina specialist, who provides a range of treatment options for individuals with AMD.
Degeneration is caused by the deterioration of the central portion of the retina, the inside back layer of the eye that records the images we see and sends them via the optic nerve from the eye to the brain. The retina’s central portion, the macula, is responsible for focusing central vision in the eye.
Types of Age-related Macular Degeneration
This form is quite common. About 8 out of 10 people who have AMD have the dry form. Dry AMD is when parts of the macula get thinner with age and tiny clumps of protein grow. There is slow loss of central vision. Although there is currently no way to treat dry AMD, age-related eye disease studies have shown that a vitamin supplement can slow the progression.
This form is less common but much more serious. Wet AMD is when new, abnormal blood vessels grow under the retina. These vessels may leak blood or other fluids, causing scarring of the macula. Vision loss is faster with wet AMD than with dry AMD. There are treatment options for wet AMD, primarily the injection of medication into the eye to stabilize the disease. Injections, although not a cure, need to be done at intervals and have been successful at reducing vision loss. Occasionally, laser treatment can also be beneficial.
Dry and wet eye are not mutually exclusive. Patients with dry changes can progress to wet AMD which is why it is so important for patients to monitor vision changes at home and to schedule periodic exams.
- The most significant risk factor for AMD is age, with risk increasing as one grows older.
- Genetics play a big role and 3-4 genes have been isolated as contributing factors in the development of AMD.
- AMD is more common in individuals with fair complexion than in pigmented races.
- Smoking is a significant risk factor and doubles the risk of AMD.
The Importance of Screening
Many people don’t realize they have AMD until their vision is very blurry. This is why it is important to have regular visits to an ophthalmologist who can look for early signs of AMD before vision problems become apparent.
- During a visit, your visual acuity will be checked to assess sharpness of vision. Both front and back parts of the eye will be checked. The back part of the retina will be examined through a dilated pupil.
- Often fundus photography and/or OCT tomography will be used to detect any subtle fluid in the retina.
- Your doctor can provide you with an Amsler Grid for use at home. Cover one eye and focus on the dot in the center. While looking at the dot, you should be aware of the lines of the grid. If you notice any blurred, wavy, or missing lines, you should contact our office as soon as possible. You can periodically test yourself at home to monitor any changes in your vision. To print a grid or for more instructions, visit: http://www.amd.org/the-amsler-grid/
There is currently no known cure for macular degeneration, but there are ways to reduce risk and possibly slow the progression after diagnosis.
Antiangiogenic drugs. These medications are injected into the eye to stop new blood vessels from forming and block the leaking from the abnormal vessels that cause wet AMD. Some people who take these drugs have been able to regain vision that was previously lost. Injections need to be repeated at intervals.
Laser therapy. High-energy laser light can sometimes destroy actively growing abnormal blood vessels from AMD.
Photodynamic laser therapy. A two-step treatment that uses a light-sensitive drug to damage abnormal blood vessels. Medication is injected into the bloodstream, which gets absorbed by the abnormal blood vessels. A laser is then shined into the eye to activate the drug, which damages the abnormal blood vessels.
Vitamins. A study by the National Eye Institute found that it can be beneficial to take a supplement formula that has vitamins C and E, beta-carotene, zinc, and copper. According to the research, the risk for vision loss goes down for some people with intermediate to advanced dry AMD.
Low vision aids. Devices are available that have special lenses or electronic systems that enlarge images of nearby objects.
Lifestyle changes. Dieting, exercise, avoiding smoking, and eye protection can be beneficial in reducing risk.
Researchers are continuously studying new possible treatments for AMD.
Annual visits, especially after age 50, are critical to watch for warning signs of AMD and prevent rapid deterioration. Early intervention can have positive results in halting, reversing, or slowing the progression of macular degeneration and the vision changes that accompany it.
Please make an appointment with one of our general ophthalmologists for an initial screening. Our retina specialist, Dr. Edward Fitzpatrick, is available for consultation and treatment to slow disease progression.
Sources: American Macular Degeneration Foundation; American Academy of Ophthalmology; WebMD, AMD.org