Age-related macular degeneration (AMD) is one of the most common causes of poor vision after age 60. AMD is a deterioration or breakdown of the macula. The macula is a small area at the center of the retina in the back of the eye that allows us to see fine details clearly and perform activities such as reading and driving.
The visual symptoms of AMD involve loss of central vision. While peripheral (side) vision is unaffected, with AMD, one loses the sharp, straight-ahead vision necessary for driving, reading, recognizing faces, and looking at detail.
Although the specific cause is unknown, AMD seems to be part of aging. While age is the most significant risk factor for developing AMD, heredity, blue eyes, high blood pressure, cardiovascular disease, and smoking have also been identified as risk factors. AMD accounts for 90% of new cases of legal blindness in the United States.
Nine out of 10 people who have AMD have atrophic or " dry" AMD, which results in thinning of the macula. Dry AMD takes many years to develop. A specific vitamin regimen has been shown to slow progression of dry AMD.
Exudative or " wet" AMD is less common (occurring in one out of 10 people with AMD) but is more serious. In the wet form of AMD, abnormal blood vessels may grow in a layer beneath the retina, leaking fluid and blood and creating distortion or a large blind spot in the center of your vision.
Researchers have found that a chemical called vascular endothelial growth factor, or VEGF, is critical in causing abnormal blood vessels to grow under the retina. Scientists have developed several new drugs that can block the trouble-causing VEGF. These are referred to as "anti-VEGF" drugs, and they help block abnormal blood vessels, slow their leakage, and help reduce vision loss.
Treatment with the anti-VEGF drug is usually performed by injecting the medicine with a very fine needle into the back of your eye. Your ophthalmologist (Eye M.D.) will clean your eye to prevent infection and will administer an anesthetic into your eye to reduce pain. Usually, patients receive multiple anti-VEGF injections over the course of many months. There is a small risk of complications with anti-VEGF treatment, usually resulting from the injection itself. However, for most people, the benefits of this treatment outweigh the small risk of complications.
Anti-VEGF medications are a step forward in the treatment of wet AMD because they target the underlying cause of abnormal blood vessel growth. This treatment offers new hope to those affected with wet AMD. Although not every patient benefits from anti-VEGF treatment, a large majority of patients achieve stabilized vision, and a significant percentage can improve to some degree.
Promising AMD research is being done on many fronts. In the meantime, high-intensity reading lamps, magnifiers, and other low vision aids help people with AMD make the most of their remaining vision.