What is Age-related Macular Degeneration?

A Normal Macula

Age-related macular degeneration (AMD) is the leading cause of blindness in people over 65 years of age. There is deterioration of the central part of the retina, the macula, which is the area that allows us to see color and detail. This is essential for activities such as driving, reading, and threading a needle.

The peripheral retina surrounds the macula. It is responsible for side and night vision, and it is not affected in AMD. For example, you might see the outline of a clock, but would not be able to tell what time it is.

ABOUT MACULAR DEGENERATION

Wet Macular Degeneration

In AMD, there is a breakdown and deterioration of the macular tissue. When the macula is not functioning properly, we experience blurriness or darkness in the center of our vision. Both distance and near vision are affected.

Symptoms begin as blurred or distorted central vision and can progress to total loss of central vision. Total blindness does not occur. Therefore, people continue to have some useful vision and are able to take care of themselves

WHAT CAUSES MACULAR DEGENERATION?

Dry Macular Degeneration

AMD is most commonly a result of the body’s natural aging process. There are two types of AMD. One is the dry or atrophic type and the other is the wet or exudative type.

Most people have the dry type of macular degeneration. In this type, the tissues break down and become thin with aging causing gradual loss of vision.

Wet macular degeneration accounts for about 10% of all cases. It results when aging of the retina is compounded by growth of abnormal blood vessels underneath the macula. These vessels leak fluid and/or blood that blur central vision. Visual loss may be rapid and severe with significant distortion as a result of dense scar tissue formation.

Another Example of Wet Macular Degeneration

WHAT ARE THE SYMPTOMS?

Symptoms are variable. The condition may not be noticeable in its early stages. Sometimes there is loss of vision in only one eye while vision remains good in the other eye for many years.

When both eyes are affected, the loss of central vision is usually noticed earlier. Some common ways visual loss is detected include:

• Words in the center of a page appear blurred
• A dark or blind spot appears in the center of vision
• Straight lines appear wavy or distorted

HOW IS MACULAR DEGENERATION DIAGNOSED?

Many people do not realize that they have a macular problem until blurred vision becomes obvious. Your ophthalmologist can detect early stages of the disease during an eye examination by:

• Viewing the macula with a lighted instrument called an ophthalmoscope
• Performing a simple test in which you look at a grid resembling graph paper
• Taking special photographs after a dye is injected in the arm to locate abnormal blood vessels. This procedure is called fluorescein angiography

HOW IS MACULAR DEGENERATION TREATED?

Despite ongoing research, there is no cure yet for dry AMD. Some doctors believe that nutritional supplements may slow the degenerative process. Treatment focuses on helping the patient find ways to cope with visual impairment.

In its early stages, wet macular degeneration can be treated with laser surgery, a brief and usually painless outpatient procedure. Laser surgery uses a highly focused beam of light to seal the leaking blood vessels that damage the macula. Although a "blind spot" is left at the point of laser contact, the procedure can preserve more sight overall.

Despite advanced medical treatment, people with AMD still experience some visual loss. A wide range of low-vision devices, support services, and rehabilitation programs are also available to help patients maintain a satisfying lifestyle.

For more information about AMD, please visit the Macular Degeneration Foundation website by clicking here