Retinitis pigmentosa, or RP, is the name given to one of a group of diseases which affect the retina of the eye. It is estimated that 400,000 Americans are affected by RP and other RP like inherited retinal degenerations.
Some of the most common symptoms of RP include night blindness and loss of peripheral (side) vision.
Symptoms of RP often appear for the first time during the childhood or adolescent years. Stumbling over objects which seem to be in plain sight and "clumsiness" may be the first indications of a problem. The symptoms of RP generally worsen over a period of years. Although some RP patients with advancing age may become blind, most will retain at least some vision, and are classified as "legally blind". Each individual case differs.
Retinitis pigmentosa develops inside the pigmented layer of the retina. The retina is a delicate layer of cells that acts like the film in a camera. It picks up a picture and transmits it to the brain – where "seeing" actually occurs. Two types of cells in the retina that participate in sending visual messages to the brain are the rod and cones. The rod-shaped cells are mostly used to help you see "out of the corners of your eyes" (peripheral vision) and to see at night. The cone-shaped cells enable you to distinguish colors, see during the day and help you see with your central vision.
When RP begins, the rod-shaped cells begin to lose their ability to function. As a result, people with this condition frequently have trouble seeing at night or in areas of dim light. It should be noted that poor and decreased night vision alone is not necessarily an indicator of retinitis pigmentosa.
"Tunnel vision" is also a symptom of RP. The field of vision gradually narrows and to the RP patient, the effect is as though the person is constantly looking through a tunnel.
As RP progresses to an advanced stage, you may also have difficulty reading, distinguishing colors and seeing distant objects clearly. This is due to the deterioration of the cone-shaped cells.
Your optometrist may be able to help you in maximizing your remaining vision by prescribing special low vision aids. Some of the optical aids available include telescopic lenses for distance vision, microscopic lenses, magnifying glasses, electronic magnifiers, night vision scopes, special filers and field enhancers.
Unfortunately, although extensive research is being conducted, no treatment is available at this time to reverse the course of this condition. However, early counseling by your optometrist can help you in successfully adjusting your lifestyle and career goals to this visual impairment. Potential problems can also be identified and forestalled by determining appropriate aids, training and other job modifications in your chosen career field. When RP is diagnosed early, you can often take full advantage of educational and career guidance.