The retina is the delicate innermost layer of tissue that lines the eye. It contains layers of light receiving cells called photoreceptors that are connected to the brain by the optic nerve. If you think of the eye as a camera receiving images, then the retina is the film on which those images are recorded. Beneath the retina is the retinal pigmented epithelium (RPE). The RPE supports the function of photoreceptor cells (cone and rod cells) in the retina.
Both cone and rod cells convert light into electrical impulses which travel through several types of nerve cells to the optic nerve, which then carries the signal to the brain, where “seeing” actually occurs. With retinitis pigmentosa, photoreceptor cells begin to degenerate and eventually stop functioning.
The basic cause of retinitis pigmentosa is thought to be genetic. The disease is programmed into your cells and not caused by injury, infection or any other external agent. Genetic defects, or mutations, give faulty messages to the retinal cells, leading to their progressive degeneration. This in turn, leads to vision loss.
It is important to remember that because RP is an inherited disorder, it commonly affects other members of a family. If someone in your family is diagnosed with a retinal degeneration, it is strongly advised that all members of the family contact an eye care professional.
- Peripheral (or side) vision will be affected
- Night blindness or impairment
- Loss of central vision
- Color perception impairment
- Gradual vision loss
- Macular edema
While researchers are gaining new understandings about the precise genetic causes of RP and the actual mechanisms of the disease, so far research has not found a way to halt the degeneration of the retina or to restore lost vision.