Macular degeneration is an eye disorder that damages the center of the retina, which is called the macula. This makes it difficult to see fine details.
The retina is the layer of tissue at the back of the inner eye. It changes light and images that enter the eye into nerve signals that are sent to the brain. The macula is the part of the retina that makes our vision sharper and more detailed.
Macular degeneration is caused by damage to the area around blood vessels that supply the macula. This change in the blood vessels damages the macula.
Two phases of macular degeneration (AMD) exist:
Scientists arenÃ¢â‚¬â„¢t sure what causes AMD. The disease is most common in people over 60, which is why it is often referred to as age-related macular degeneration.
In addition to heredity, other risk factors are:
At first you may not have symptoms. As the disease progresses, your central vision may be affected.
The most common symptom in dry AMD is blurred vision. This is limited to the center of the field of vision. Often objects in the central vision look distorted and dim, and colors look faded. A patient may have trouble reading print or seeing other details, but can generally see well enough to walk and perform most routine activities.
As the disease becomes worse, you may need more light to read or perform everyday tasks. The blurred spot in the center of vision gradually gets larger and darker. In the later stages, you may not be able to recognize faces until people are close to you.
AMD typically does not affect side (peripheral) vision. This is very important, because it means you will never have complete vision loss from this disease.
The most common early symptom of wet macular degeneration is that straight lines appear distorted and wavy. You may also notice a small dark spot in the center of your vision that gradually gets larger. Central vision loss can occur very quickly. If this occurs, you urgently need evaluation by an ophthalmologist with experience in retina disease.
If you are over age 60 and youÃ¢â‚¬â„¢ve had changes in vision, your eye care provider will do an examination. During the exam, the doctor will use drops to enlarge (dilate) your pupils, and a special lens to view your retina and optic nerve.
The doctor will look for changes in the blood vessels and the membrane that surrounds them. This may show drusen, the yellow deposits that form on this membrane in dry macular degeneration.
You may be asked to cover one eye and look at a pattern of lines called an Amsler grid. If the straight lines appear wavy, it may be a sign of AMD.
Other tests for macular degeneration may include:
No treatment exists for dry macular degeneration. However, a combination of vitamins, antioxidants, and zinc may slow the progression of the disease. This combination of vitamins is often called the "AREDS" formula. Smokers should not use this treatment.
The recommended supplements contain:
Although there is no cure for wet AMD, treatments may include:
Low-vision aids (such as special lenses) and therapy can help you use the vision that you have more effectively, and improve your quality of life.
AMD Alliance International -- (877) AMD-7171 -- www.amdalliance.org.
Most people with mild dry macular degeneration will not have disabling central vision loss. However, there is no way to predict who will progress to a more severe form of the disease.
The wet form of macular degeneration often leads to significant vision loss.
Although macular degeneration can cause people to lose the ability to read, drive a car, and recognize faces that are not very close, it never causes complete blindness. This disorder results in the loss of central vision only -- macular degeneration cannot cause peripheral vision loss.
Nearly everyone with macular degeneration can get around, eat, perform personal hygiene, and do other routine activities without too much difficulty.
Loss of central vision may interfere with many daily activities, such as reading, working on the computer, or driving. You may need extra light or magnification to perform many of your normal activities.
If you have AMD, your health care provider may recommend that you check your vision every day on an Amsler grid. Call your provider immediately if the lines appear wavy, or you notice any other changes in your vision.
Although there is no known way to prevent macular degeneration, lifestyle factors can reduce your risk of developing the condition:
See your eye care professional regularly for dilated eye exams.
Age-related macular degeneration (ARMD); AMD; senile macular degeneration (SMD) is an older name that is no longer in common use.