Macular degeneration is an age-related condition of the macula, an area of the retina at the back of the eye that is responsible for seeing fine detail when reading or looking straight ahead. In order to see 20/20 the macula must be functioning perfected. Macular degeneration is the leading cause of decreased vision in people over 65 years of age. The vast majority of cases of macular degeneration are the dry type, in which there is thinning or deterioration of the tissues of the macula or the formation of abnormal yellow deposits called drusen. Progression of dry macular degeneration usually occurs very slowly and does not always affect both eyes equally. Wet macular degeneration occurs when abnormal or leaking blood vessels grow underneath the retina in the area of the macula. These changes can lead to distorted or blurred vision and, in some cases, a rapid and severe loss of straight ahead vision.
Macular degeneration is usually diagnosed by direct observation. Usually these changes can be seen through the use of several instruments. A chart known as an Amsler Grid can be sued in the office and a home to pick up subtle changes in your vision. Photographs and fluorescein angiography are also commonly used. Angiography provides an image of the circulation in the eye as the dye flows thru the blood vessels. Optical Coherence Tomography or OCT uses light waves to create a contour map of the retina and can show areas of thickening or fluid accumulation. In the early stages of macular degeneration, regular eye check-ups, attention to diet and nutritional supplements as well a home monitoring of vision with an Amsler grid is recommended. There has been active research on the use of vitamins and antioxidants in an attempt to prevent or slow macular degeneration.
Antioxidants are thought to protect against the damaging effects of oxygen charged molecules called free radicals. An important group of antioxidants are called carotenoids. These are pigments which give fruits and vegetable their color. Two such carotenoids are lutein and zeaxanthin. Some research studies suggest that people who have diets high in lutein and zeaxanhthin may have a lower risk of developing macular degeneration. Kale, raw spinach, and collard greens are notably high in lutein and zeaxanthin. There are many nutritional supplements that are high in lutein and other antioxidants that are based on those vitamins used in the research studies. Treatment for macular degeneration, essentially the wet form, had traditionally relied on laser therapy. Abnormal blood vessels were destroyed in an attempt to improve the surrounding retinal tissues. Today while laser is still used it has been supplanted by injectable medications called anti-angiogenesis agents or anti-VEGF agents that help to stop the formation of new blood vessels and dry up those that are present. Avastin and Lucentis were the original medications used but newer and longer acting compounds are being developed and studied. Many patients require repeated injections usually every 4-6 weeks and the cost of these medications can be quite high. Going forward it is hoped that we will find a longer acting agent that is also cost effective. Nonetheless the results from these anti-angiogenesis agents have been remarkable compared to the old days of laser and freezing therapy.
In terms of vision unfortunately once vision is lost due to macular degeneration we are unable to substantially recover it. Low vision aids- strong magnifiers and special glasses can be utilized to help improve function from the loss of vision. Having lots of good light and using e-books which allow magnification of reading material in a snap are two easy ways to improve function. The exact cause of macular degeneration is not known. Age is the most significant risk factor. Women may be at slightly greater risk and the risk seems to be higher in Caucasians than in African Americans. Smoking has been shown to be a major risk factor. High blood pressure, long term sun exposure and high cholesterol may also be factors.