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Retina and macula
What does someone with retinitis pigmentosa see?
Retinitis pigmentosa (RP) changes vision slowly, and the pattern is hard to describe in words. This simulator shows an original street scene the way it might look at different stages of RP, in daylight, in dim light and in bright light, so that family members, friends, teachers and employers can understand what someone with RP is dealing with. It is an illustration, not a test, and it cannot show your own vision.
Early RP. Night vision is usually affected first, often in childhood or the teenage years. In daylight, side vision may still seem normal, while patchy gaps partway out from the center show up mostly in dim light. Central vision and reading are usually still good.
Middle RP. Side vision loss becomes noticeable in daylight. The gaps often join into a ring partway out from the center, leaving central vision and sometimes a little far side vision. Bumping into things, missing steps and curbs, light sensitivity and glare are common.
Late RP. Only a small central island of vision, a few degrees across, may remain. Central sharpness can also drop, for example from cataract or swelling at the center of the retina (cystoid macular edema), and both of these can be treated.
The scene is drawn as if it spans about 90 degrees of view, so a remaining field 20 degrees across covers about two-ninths of its width. Middle RP is shown with a central field about 30 degrees across inside a ring-shaped gap, and late RP with a field about 10 degrees across and reduced sharpness. In dim light, the RP field is shown 30% narrower and the scene darker. A visual field of 20 degrees or less across in the better eye meets the U.S. legal blindness definition used by Social Security.
RP can be caused by changes in many different genes, and its course differs from person to person, even within one family. Real field loss is not seen as a dark frame: the brain fills in the gaps, which is one reason people with RP may not notice what they are missing. Only an eye examination with visual field testing, OCT and sometimes an ERG can show your own pattern, so ask your eye doctor what your results mean.
Book an eye exam if you or your child has unusual trouble seeing at night, bumps into things often, or has a family history of RP or Usher syndrome. If you already have RP, tell your eye doctor promptly about new blur, distortion or any sudden change in vision, because some complications, such as cataract and swelling at the center of the retina, can be treated.
For information only. These tools explain numbers and do not replace an eye examination or your eye doctor’s advice. Values you enter stay in your browser.