A disorder that decreases vision over time, due to loss of function in the retina of the eye. Side and night visions get worse over time and, if the disease advances, central vision often gets worse as well.
Symptoms
Each individual who has retinitis pigmentosa will experience it in a different way. How fast the disorder progresses will also differ from one person to another. A vision problem in low light or darkness is often the first symptom, and the loss of peripheral vision is usually the next to go. Many will have a hard time clearly making out details such as letters, numbers, or certain images.
Over time the disease often advances, which results in tunnel vision and often the deterioration of central vision. Retinitis pigmentosa does not usually lead to the complete loss of vision, although in a few people it does lead to blindness.
Causes
The majority of cases of retinitis pigmentosa have a genetic-linked cause. This may include an X chromosome genetic mutation, or an inherited recessive or dominant gene. Retinitis pigmentosa can also be a result of other genetic syndromes such as Refsum disease, Bassen-Kornzweig disease, Alport syndrome, or Waardenburg syndrome. Not all genetic causes are inherited. In rare cases, the abnormal development of the embryo can lead to the disease.
Managing the Condition
No known treatment is currently available for those with retinitis pigmentosa, but there are a number of ways to help ease certain symptoms.
- Vitamin A- High doses of this vitamin has been shown to possibly decrease the speed of progression. Recommended doses are at around 1½ to 2 times the normal amount. This can lead to toxicity in certain individuals, so patients should speak with their healthcare provider first.
- Filtered Glasses- Because many individuals are bothered by bright lights, an amber filter that has been mounted to eyeglasses may help.
Gene Therapy- This experimental therapy is being researched to see how mutated genes can be deactivated or replaced.
