Age-related macular degeneration (AMD) is the leading cause of legal blindness in people over age 55. It affects over 10 million adults in the U.S. alone.
AMD is the physical disturbance of the center of the retina called the macula. Roughly the size of the capital letter "O" in this sentence, the macula is the part of the retina that provides our most acute and detailed vision for reading, driving, and performing other activities that require fine, sharp, straight-ahead vision.
There are two types of macular degeneration:
Dry macular degeneration --Affects about 90% of those with the disease. Small yellow deposits, known as "drusen" accumulate underneath the macula. These drusen may cause the important vision cells to slowly break down. With less of the macula working, you may start to lose central vision in the affected eye as the years go by.
Wet macular degeneration -- While occurring in only 10% of all people with AMD, it actually accounts for 90% of all severe vision loss from the disease. It occurs when new blood vessels start to grow into places in the macula where they should not be. This causes rapid damage to the macula that can lead to the loss of central vision in a short period of time.
What Are The Symptoms?
In the early stages of AMD, the patient may not experience any symptoms. An eye doctor usually notices the first indicator of this disease during a routine visit. A dilated eye exam can detect small yellow deposits, known as "drusen", located in and under the macula, or the presence of abnormal blood vessels. If drusen are found, it is often the first physical sign that macular degeneration may have developed.
As drusen accumulate, the cells that transport nutrients into the retina are lifted further and further away from their blood supply, impairing the transport of vital substances to the macular area of the retina. This can lead to distortion and deterioration of vision. Since macular degeneration is often part of the natural aging process, people experience different symptoms. For many it is hardly noticeable, others may notice:
- Blurred vision
- A dark or empty area in the central area of vision
- Visual distortion of straight lines
How Can It Be Treated?
In its early stages, wet macular degeneration can be treated with laser surgery.
Currently there is no treatment for dry macular degeneration. Since peripheral vision is not affected, people can continue many of their favorite activities using low-vision optical devices such as magnifying glasses.
In a recent important study, people at high risk for advanced AMD lowered their risk by about 25%. They were treated with a high dose combination of vitamin C, vitamin E, beta-carotene, and zinc (ref: AREDS study).
Bausch & Lomb provided the high-potency, antioxidant vitamin and zinc supplement evaluated in the AREDS study. This unique formulation is now being sold as Bausch & Lomb PreserVision® AREDS eye vitamin, the vitamin and mineral supplement used in the National Eye Institute's Age-Related Eye Disease Study (AREDS).
What Is Involved In Surgery?
Surgery for wet macular degeneration is a brief and usually painless outpatient procedure. The doctor uses highly focused laser beams to seal the leaking blood vessels. In most cases, the procedure preserves overall sight, although a small, permanently dark spot is left where the laser makes contact, leaving vision slightly impaired. Bausch & Lomb has a number of precision instruments used for this surgery.
Photo courtesy of National Eye Institute, National Institutes of Health.