What Can I Do About RP? Current Therapy and Ongoing Research for RP
Retinitis pigmentosa (RP) is a group of rare genetic eye disorders that cause progressive degeneration of the retina, the light-sensitive layer of tissue at the back of the eye. The retina contains photoreceptor cells called rods and cones. These cells detect light, process visual information, and help transmit signals through the optic nerve to the brain.
In people with RP, rods and cones gradually deteriorate, resulting in progressive vision loss. Most forms initially affect the rods, which support night vision and peripheral, or side, vision. Cone function may become affected later, leading to reduced central vision, color perception, and the ability to see fine details.
RP may occur by itself or as part of a condition that affects other parts of the body. Related inherited retinal diseases and syndromes include Usher syndrome, Leber congenital amaurosis, Bardet–Biedl syndrome, rod-cone dystrophy, and choroideremia. Usher syndrome, for example, affects both hearing and vision and commonly includes RP.
The age at which symptoms begin varies considerably. Signs may appear in childhood, adolescence, or adulthood, depending on the genetic form of the disease. The rate of progression and the degree of vision loss also differ greatly from one person to another. RP is inherited in several different ways, although a person may have no previously known family history of the condition.
What Are the Symptoms?
Symptoms vary according to which photoreceptor cells are affected first.
In the most common forms of RP, rods deteriorate before cones. Because rods are especially important for seeing in dim light and for peripheral vision, early symptoms commonly include:
- Difficulty seeing at night or in dimly lit environments
- Slow adjustment when moving between bright and dark areas
- Reduced peripheral vision
- Difficulty noticing objects, steps, or people to the side
- Blind spots that may gradually merge and produce “tunnel vision”
Night blindness is often one of the earliest symptoms and may become noticeable during childhood or adolescence.
As the condition progresses and cones become involved, symptoms may include:
- Reduced visual sharpness
- Difficulty distinguishing colors
- Increased sensitivity to bright light
- Loss of central vision
- Difficulty reading, recognizing faces, driving, or performing other detailed tasks
Some less common inherited retinal disorders primarily affect cones before rods. In these conditions, reduced central vision, impaired color vision, and sensitivity to light may occur before night blindness or peripheral vision loss.
Many people with RP retain useful central vision for years or decades, even after substantial peripheral vision loss has occurred. Others experience earlier or more extensive central vision loss. Although many people with RP eventually meet the legal definition of blindness, the age at which this occurs—and the amount of usable vision that remains—varies widely. Legal blindness does not necessarily mean complete loss of sight.