ARMD

Age-Related Macular Degeneration

What is ARMD?

Age-Related Macular Degeneration is the leading cause of severe vision loss in people over age 55. Macula, is the small central portion of the retina, responsible for central vision. The retina is the light-sensing tissue at the back of the eye. It is called age-related macular degeneration (AMD) because the disease is more likely to develop as a person ages. Even though macular degeneration is almost never a totally blinding condition, it can be a source of significant visual disability.

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There are two main types of age-related macular degeneration:

Dry form. The "dry" form of macular degeneration is a more common form, characterized by the presence of yellow deposits, called drusen, in the macula. While a few small drusen may not cause changes in vision, they may grow in size and increase in number, leading to decrease or distortion of vision. In more advanced stages of dry form of macular degeneration, there is also a thinning of the macula leading to atrophy, or tissue death. During any of these stages patients may have blind spots in the center of their vision. In the advanced stages, patients may lose central vision.

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Wet form. The "wet" form of macular degeneration is less common, but can be more devastating to the vision. It is characterized by the growth of new abnormal blood vessels from the layer underneath macula, called choroid. This is called choroidal neovascularization. These blood vessels can leak blood and fluid into the retina. These abnormal blood vessels eventually scar, leading to permanent loss of central vision.

Most patients with macular degeneration have the dry form of the disease. However, the dry form of macular degeneration can lead to the wet form. That is why it is very important for people with macular degeneration to monitor their eyesight carefully at home and have regular dilated eye exams

Symptoms of Age-Related Macular Degeneration

In its early stages, macular degeneration may not have symptoms. The first sign is usually distortion of straight lines. This may progress to a gradual loss of central vision. Symptoms of macular degeneration include:

  • Straight lines start to appear distorted
  • Dark, blurry areas or white out appears in the center of vision
  • Diminished or changed color perception
  • Difficulty with dark adaptation after light exposure
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Diagnosis of Age-Related Macular Degeneration

Age-related macular degeneration can be detected in a routine dilated eye exam. Early detection of age-related macular degeneration is very important because there are treatments that can delay or reduce the severity of the disease. If you are diagnosed with age-related macular degeneration, you may need to have different tests to assess the degree of the involvement. One of the tests is the procedure called angiography. In this procedure, a dye, such as fluorescein or indocyanine green, is injected into a vein in the arm. Photographs are taken as the dye reaches the eye and flows through the blood vessels of the retina. If there are new vessels or vessels leaking fluid or blood in the macula, the photographs will show their exact location and type.

There is current research to develop a test that can help with deciding if a person has increased risk of progression of age-related macular degeneration.

Risk Factors for Age-Related Macular Degeneration

As the name suggests, the risk of age-related macular degeneration increases with age. In fact, it is the leading cause of severe vision loss in adults over age 55.

There may be hereditary predisposition, meaning it can be passed on from parents to children. If someone in your family has or had the condition you may be at higher risk for developing it.

Smoking, high blood pressure, high cholesterol, obesity, and being Caucasian are also risk factors for macular degeneration.

Treatments for Age-Related Macular Degeneration

There is currently no cure for macular degeneration. There are treatments that may prevent severe vision loss or slow the progression of the disease considerably. Several options are available, including:

  • Vitamins. A large study performed by the National Eye Institute of the National Institutes of Health, called AREDS (Age-Related Eye Disease Study), showed that for certain level of the disease, specific concentrations of vitamins C, E, beta carotene, zinc and copper can decrease the risk of vision loss. Ask your eye doctor if these vitamin supplements will benefit you before taking them.
  • Anti-angiogenesis drugs. These medications are used for wet form of the age-related macular degeneration. They block the development of new blood vessels and stop leakage from the abnormal vessels already present. This treatment revolutionized the approach to treatment of this usually severe form of the disease.

In addition, there are other medications and laser therapies that can be helpful in certain types of the disease. Having a thorough examination and discussion with your doctor will help in deciding on the best course of action.

There are many treatments that are still in the research and experimental phases. The new developments are coming out all the time. Look under NEWS on our website or ask your doctor about it.

Prognosis and Outlook for People Age-Related Macular Degeneration

People rarely lose all of their vision from age-related macular degeneration. They may develop poor central vision, but most are still able to perform many normal daily activities and live full lives.

The dry form of age-related macular degeneration is much more common and tends to progress more slowly. However, most of the current therapies are for the wet form of age-related macular degeneration.

Unfortunately, even with proper treatment, age-related macular degeneration can recur in the same or other eye. Because of this, regular home testing and regular dilated eye exams, as recommended by your doctor are necessary.

Do not be discouraged. New therapies are coming out all the time. There is hope on the horizon!

For more information, click on following links:

http://www.nei.nih.gov/health/maculardegen/armd_facts.asp

http://www.asrs.org/patients/retinal-diseases/2

http://www.allaboutvision.com/conditions/amd.htm