What is retinitis pigmentosa?
Retinitis pigmentosa (RP) is one of a group of rare, progressive inherited retinal diseases (IRDs) that can cause severe vision loss and eventual blindness. Individual IRDs are caused by at least one dysfunctional gene. IRDs affect people of all ages, manifests as various types of damage to the retina (a light-sensitive layer of tissue at the back of the eye), and can progress at different rates in different people, even within the same family.
The term RP itself covers several disease variants that cause the breakdown of retinal cells over time. The condition affects about 100,000 people in the U.S.. Symptoms generally start appearing in childhood or adolescence, and most people with RP are considered legally blind before the age of 50.
Symptoms of retinitis pigmentosa
The loss of night vision, and difficulty navigating in dim lighting, is one of the earliest symptoms of RP, along with blind spots in your peripheral (side) vision. Not being able to see objects out of the corners of your eyes may lead you to bump into things or trip over objects that are right in front of you. Over time, your field of vision narrows until you only have a small amount of central, or forward, vision, also referred to as “tunnel vision”.
Other symptoms of RP often include eventual loss of color vision, and severe sensitivity to bright light.
Causes of retinitis pigmentosa
RP is primarily caused by gene mutations that are passed down from parent to child. The expression of the same mutated genes can result in different symptoms in different people, however.
RP can also occur as part of, along with, or as a result of other rare genetic conditions, eye injuries, infections, and medication side effects.
How is RP diagnosed?
Eye doctors diagnose RP using a comprehensive eye exam that involves dilating your pupils, conducting a chart test, taking retinal photographs, and assessing your field of vision. These are all painless and non-invasive.
Other tests that may be performed to determine and confirm an RP diagnosis include:
- Optical coherence tomography (OCT),
- Autofluorescence imaging, and
- Genetic testing.
How is RP treated?
There is currently no cure for RP, but low-vision aids and rehabilitation (training) programs can help you optimize your vision and maintain your quality of life. Most treatments are geared toward slowing the advancement of vision loss, and addressing complications. These can include:
- Neuroprotective medication,
- Gene therapy, and
- Retinal prosthetics.
Some physicians also recommend vitamins and other supplements to help slow vision loss. Overdosing on even natural, over-the-counter substances can have serious adverse health effects, however, so speak with your doctor before beginning any sort of supplement regimen.