MN DeafBlind



Vision problems in Retinitis Pigmentosa (RP)

RP is a progressive disorder which affects first the rods and then the cones of the retina, which is the back layer of the eye. The effects are:

Night vision problems like being afraid of the dark, stumbling when going across campus, bumping into things in dark hallways, being unable to see the teacher signing when she is standing next to (but not in the light of) an overhead projector or film clip.

Blind spots: in the peripheral vision: About midway between the pupil and the shoulder, blind spots occur. At those spots information simply disappears. These start out small and then enlarge, joining the others to form a ring. The blind spots are not noticeable at first. When they are big enough, the students will not notice things on the floor, bump into objects, not realize someone is waving or trying to get their attention, etc. The most important problem, however, is that they begin to have problems following a rapid conversation in a classroom particularly if everyone is signing.

Tunnel vision: Once the blind spots get big enough, they block out all peripheral vision and the students can only see whatever they are looking at directly. At this point (which can be as early as 10 years old in USH1), they no longer like to play ball sports because they cannot find the ball. Bumping into people and things becomes more noticeable. Most importantly, they cannot follow a conversation among 3 or more people without the assistance of an interpreter (USH1) or microphones on each speaker (USH2).

Tunnel vision graphic

Glare: Moving from a dim to light environment is like walking out of a dark theater into bright sunlight. Going from light to dim is like walking into a cave with no light at all. The remarkable thing is that dim is not black as most of us know it. It is like twilight or a hall that does not have light for a stretch of only 10-15 ft. Unless coached to do differently, the students will stop in a door or the middle of the hall and just wait until they can see, which could be 5-10 minutes or even longer. They need to learn to step to the side.

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