Achromatopsia

What is achromatopsia?

Two kinds of nerves are in the back of the eye. The nerves get the light through the pupil. They send visual messages to the brain. One kind of nerves is called rods. The other is called cones. The cones can send messages about still objects, details and color. The cones let us read and look at pictures. Sometimes the cones do not work. That is called achromatopsia. "A" means "no" in Latin and "choma" means "color." "Opsia" means "eye." This eye problem is also called stationary cone dystrophy and rod monochromatism. Some people who have achromatopsia also have nystagmus. Their eyes move back and forth without them wanting them to. You can read more about nystagmus on this website.

What causes achromatopsia?

Achromatopsia is an inherited eye condition. That means that a baby is born with it. When people have a baby, the baby's body has many things that the parents' bodies have. For example, a mother may have curly hair, and her baby may have curly hair just like hers. The father may have brown eyes, and his child will probably have brown eyes, too. But it is possible that two parents who have curly hair could have a baby with straight hair. Two parents who have brown eyes could have a baby who has blue eyes. They have the gene that makes straight hair and blue eyes hidden in their bodies.

Parents who have children who have achromatopsia may not have known that they have achromatopsia in their bodies. It was hidden. They may not know that achromatopsia is in their body cells until they have a child who has achromatopsia. Or they may remember that someone else in the family had achromatopsia.

What kind of vision do people have who have achromatopsia?

People who have achromatopsia see less clearly than people who are fully sighted. They see best when things are moving or when they are moving themselves. They see best in dim light. They may like to look, then close their eyes and see the image that stays in their eyes after they close them. They cannot tell the difference between some colors. Often they are farsighted. If they are farsighted, glasses may help them. You can read more about being farsighted by looking up hyperopia on this website. Hyperopia is the medical word for farsighted.

What will help you if you have achromatopsia?

  1. Glasses may help you see things that are close to you.
  2. Sunglasses will help you in bright light. Try out some sunglasses with red tint. Many people who have achromatopsia like glasses with a dark red tint. You may like another color better. Try sunglasses that wrap around your face and that have a frame that shades your eyes from above.
  3. Wearing a hat with a dark brim may also help when the sun is bright. It can also help when the lights in class are too bright.
  4. Try to get lights that you can make bright or dim yourself. Sit and stand so that light is behind you or next to you.
  5. Before you turn on the computer or the TV, see if there is light glaring on the dark screen. Move the screen so light does not reflect on it before you turn it on.
  6. You may want to learn braille if it is too hard to read print or if the print you read is too big for most books.
  7. You may want to use a white cane when the sun is very bright. It may help you not bump into things or trip.

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