Cortical Visual Impairment (CVI)
What is CVI?
People who have CVI often have other disabilities as well. They may have cerebral palsy. That means that their brains have trouble making their body parts move or stop moving when the person wants them to.
What causes cortical visual impairment?
What kind of vision do people have who have CVI?
The vision may change all day long. People who have CVI may see something in the morning that they cannot see later in the day. Sometimes people think they are playing games when they cannot see things. They may say, “You saw that before, why don’t you see it now?”
Some people who have CVI love to look at lights. Other people who have CVI hate to look at lights. Sometimes it is hard for people who have CVI to see when there is too much light. This is called “glare.”
People who have CVI have a hard time looking at more than one thing at the same time. They like to bring things close to their eyes so that they can just see one thing up close. When a plain background is behind the thing they want to look at, it helps them see that thing. It also helps to have things spread out instead of bunched up. When things are bunched up, it is hard for people who have CVI to tell where one thing ends and another begins. Sometimes they just see the outside shape of the whole bunch of things. They do not see the inside shapes.
It can be hard to read for people who have CVI. The letters may look like they are bunched up or crowded. People who have CVI may see only the first letter and the last letter in a word.
Some people who have CVI see better when they are moving, and they see things that are moving better. It is hard for them to read or see pictures when they are sitting still.
People who have CVI need more time to think about what they are doing than people who don’t have CVI. When people who have CVI look at something, they sometimes need to stop looking and think. Then they can move their hands to the thing they saw.
Sometimes it is hard for people who have CVI to use their eyes when they are sitting up. It makes them tired to sit up. They need to rest their heads to use their eyes. Sometimes they like to read or look at pictures when they are lying down. They like to have a good chair to lean on when they read.
People who have CVI may feel tired after using their eyes. They may need to take a break from using their eyes.
Sometimes people who have CVI need to look at things from the side of their eyes. Other people may think they are not looking at the right thing.
Some people who have CVI like to look at colors. They see color best.
Many people who have CVI can see things best if the background is very different from the thing they are looking at. If the background is dark and the letters are white or yellow, they can see them. If the background is light gray and the picture is dark gray, it will be hard to see.
What will help you if you have CVI?