Retinitis Pigmentosa (RP) is a group of genetic disorders that affect the retina’s ability to respond to light. This inherited disease causes a slow loss of vision, beginning with decreased night vision and loss of peripheral (side) vision. Eventually, resulting in blindness. Unfortunately, there is no cure for RP.
The retina consists of a layer of light-sensing cells that line the back of the eye and are responsible for converting light rays into nerve impulses. These impulses are passed on from the optic nerve to the brain, where image recognition happens.
With RP, cells in the retina called rods and cones, die. Rods cells which are found largely in the outer regions of the retina and the ones in charge of ensuring the peripheral and night vision are the first to degenerate in most forms of RP. Central vision and color perception are the first to get affected when the centrally located cones of retina are damaged.
Rods are more affected than cones in the early stages of RP. Night blindness and an advanced loss of the visual field which is the part of the eye that is visible at an instant when the eyes remain steady are experienced by people in RP when the rod cells die. The loss of rods eventually leads to a breakdown and loss of cones. In the late stages of RP, as cones die, people tend to lose more of the visual field, developing tunnel vision. They may have difficulty performing routine tasks such as driving, reading, recognizing faces and objects or walking without any help.
Retinitis Pigmentosa is often hereditary (runs in families). If you or your partner has RP, there may be up to a 50 percent chance that you will pass it along to your children. Ask your ophthalmologist about genetic counseling if you are planning to have children.
The rate of progression and degree of visual loss varies from person to person. Most people with RP are legally blind by age 40, with a central visual field of less than 20 degrees in diameter. Due to genetic trait related to RP in some families, males are more affected than females.
Retinitis Pigmentosa causes slow loss of vision. Symptoms start with decreased night vision and then they progress to peripheral vision loss, resulting in a “tunnel vision” effect. Some people may face difficulty in color identification. The rate of vision change varies in different people depending on the genetic makeup of their disorder.
Due to a decrease in night vision, it becomes difficult to adjust to darkness. You may stumble over objects in the dark, find driving at dusk and night difficult and 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.”
In some cases, central vision may be affected first, making detail work difficult, such as reading or threading a needle. As the central area of the retina, called the macula, is affected, this condition is referred to as macular dystrophy.
If you have poor night vision or a loss of side vision, or if there is a history of RP in your family, consult an ophthalmologist who will perform a comprehensive eye examination to check for RP.
Your ophthalmologist may use an electroretinogram to help diagnose RP. This is where electrodes are painlessly placed on the cornea (the clear front window of the eye) and around the eye to measure how retinal cells respond to flashes of light. Right results are obtained when the cells respond properly.
Another test your ophthalmologist may use in diagnosing RP is a visual field test (see photo). In this procedure, you look at a fixed point and then signal when an object appears in your side vision.
Currently there is no known cure for RP. According to research, vitamin A palmitate may help in slowing the progression of certain forms of RP. Your ophthalmologist can advise you on the risks related to the benefits of vitamin A palmitate and on the safety intake. Too much vitamin A palmitate can result in toxicity. Also, the beneficial effect of vitamin A palmitate on RP progression is not significant.
Wearing sunglasses to protect your retina from harmful ultraviolet (UV) light can also help in slowing vision loss from RP.
Retinitis Pigmentosa research is being conducted in areas such as gene therapy and transplant options. Since RP is a genetically-based disease, gene therapy has become a widely explored area of research, particularly in identifying ways to insert healthy genes into the retina. And as hereditary causes for RP are discovered, researchers hope to develop treatments to prevent its progression.
For people who have RP, it is important to remember that there are many low-vision devices, tips and rehabilitation services designed specifically to help people with low vision maintain an active and independent lifestyle. Ask your ophthalmologist for more information and resources near you.
Retinitis Pigmentosa treatment in India at Sanjeevan involves stimulating the retinal pigment epithelium by increasing the blood flow of the choroid which helps in release of neurotrophic factors, oxygenation and also improves blood supply to the rod photoreceptor cells in the retina.
In more advanced cases, our treatment focuses on improved peripheral vision, reduced photophobia, and prevents the deterioration of cone photoreceptor cells thereby preventing blindness.
The symptoms of night blindness, photophobia, poor colour separation are also treated during the course of the treatment.
Thus, our treatment helps in stopping further degeneration of the eye and helps in vision improvement.