Retinitis pigmentosa is a group of genetic disorders that affect the retina’s ability to respond to light. The retina is the layer of light-sensing cells lining the back of your eye that converts light rays into impulses. The impulses are sent through the optic nerve to your brain, where they are recognized as images.
What are the symptoms of retinitis pigmentosa?
Retinitis pigmentosa causes slow loss of vision. Symptoms begin with decreased night vision and later progress to loss of peripheral (side) vision. Some people may also have difficulty identifying colors. The rate of vision change varies in different people depending on the genetic makeup of their disorder.
As night vision decreases, the ability to adjust to darkness becomes slower and slower. You may:
- stumble over objects in the dark;
- find driving at dusk and night difficult;
- see poorly in dimly lit rooms, such as a movie theater.
While your vision during the day may be completely normal, your inability to see in dark conditions is considered “night blindness.” Loss of side vision also makes moving around more difficult, causing noticeable clumsiness from not being able to see objects below and around you. As the outer areas of vision slowly disappear, the condition commonly referred to as “tunnel vision” occurs. Many people retain a wide enough scope of useful vision for a long period of time. In some cases, central vision may be affected first, making detail work difficult, such as reading or threading a needle. This is referred to as macular dystrophy, because the central area of the retina, called the macula, is affected.
What causes retinitis pigmentosa?
Retinitis pigmentosa is thought to be caused by defects of certain genes in the body. The defects cause cells in the retina to malfunction and begin to break down. Retinitis pigmentosa is often hereditary (runs in families).
If you or your partner have retinitis pigmentosa, there may be up to a 50 percent chance that you will pass it along to your children. Ask Dr. Jovkar about genetic counseling if you are planning to have children.
Is there any treatment for retinitis pigmentosa?
Research has shown that Vitamin A can slow the progression of retinitis pigmentosa. Your ophthalmologist can advise you about the risks and benefits of Vitamin A and how much you can take safely. Research is currently directed toward finding the hereditary cause of many types of retinitis pigmentosa. As hereditary defects are discovered, it may be possible to develop treatments to prevent the progression of retinitis pigmentosa. Special low-vision aids and services can help people with poor vision continue doing many daily-life activities. Ask your ophthalmologist or contact the following organizations for more information and resources near you:
American Foundation for the Blind
11 Penn Plaza, Suite 300
New York, NY 10001
800.232.5463
www.afb.org
National Association for Visually Handicapped
NAVH New York City
22 West 21st Street, 6th Floor
New York, NY 10010
212.889.3141
www.navh.org
NAVH San Francisco
507 Polk Street, Suite 420
San Francisco, CA 94102
415.775.6284
www.navh.org