AGE-RELATED MACULAR DEGENERATION (ARMD)
Age-related macular degeneration, or AMD, seems to be getting a lot of press lately so I hope to clarify some of the facts and issues that relate to this retinal disease. As the name implies, it is a disease that is seen mostly in people over fifty. If you are sixty-five or older your chance of acquiring the disease is roughly 2%. It is found in more women than men and those people of Northern European ancestry show a higher rate of incidence than the normal population. It is a very frustrating disease because very little can be done to fix it. On the other hand, it is not totally blinding because the peripheral vision is unaffected.
Formerly known as Senile Macular Degeneration by the politically incorrect, AMD affects CENTRAL vision. That's because the macula is that part of the retina which receives images in the center of your vision. In other words, if you were to look at an ordinary sized photograph (4 x 6 or 3 ½ x 5) from a normal distance of 15 inches, the size of that photograph would represent that area of your vision seen by your macula. Anything above or below or on either side of the photograph is represented by more peripheral retinal elements and would not be affected in the case of AMD. The macula of the retina is also where you will find all of the CONE cells (remember the rods & cones from anatomy class?). These are very important nerve cells that are responsible for your most acute vision as well as your COLOR vision. When any disease affects the macula, color vision is disrupted as well as sharpness of vision.
There are two distinct types of AMD. The "dry" type is the most common, generating 90% of all cases, while the "wet" type represents the remaining 10%. The "wet" implies a bleeding or fluid leakage in the macula, whereas the "dry" implies… just that…dry. The wet form can cause a rather sudden loss of central vision but in many cases can be treated with a laser. Laser treatment has been shown to, at least, slow down the degeneration of the macula. Unfortunately, the dry form does not respond to the laser, but there have been studies that demonstrate value in anti-oxidant therapy. This implies that taking vitamins A, C, and E may prove beneficial in slowing down the degenerative process in the macula. Most retinal specialists now prescribe anti-oxidant therapy for those patients with the dry form of AMD, JUST IN CASE. They will also suggest this therapy for immediate family members, even before there is any sign of the disease. If you don't believe in vitamin supplements, stock up on those collard greens.
Difficulty reading may be the most common symptom, but macular degeneration will also affect your ability to thread a needle, drive a car, read a street sign, or recognize a face. Distorted printed material and seeing straight lines as wavy or crooked are other features of the disease. In some advanced cases, patients may see a blind spot in their central visual field. Now, before you start to believe you have AMD, remember that many of these symptoms can be related to much more common maladies, such as the BIG 4; nearsightedness, farsightedness, astigmatism, and presbyopia. These are disorders that can be corrected quite easily, so give your eye doctor a chance to ease your mind. Even in cases of AMD, there are various optical devices and low vision aids that can help patients read again, dial a telephone, watch TV, and even drive. Again, it is important to remember that complete blindness NEVER occurs, and that peripheral vision remains normal.