What is strabismus?

Strabismus is a condition that occurs when both eyes don't look at the same thing at the same time. One eye may look straight ahead while the other eye looks in another direction. It is sometimes called "cross-eye" or "walleye."

What causes it?

Sometimes adults have strabismus from childhood. Childhood strabismus often has no known cause. But it tends to run in families.

Adults may develop strabismus from eye or blood vessel damage. Other causes include loss of vision, a tumour in the eye or brain, Graves' disease, stroke, and diabetes. Some muscle and nerve disorders can also cause it.

What are the symptoms?

The most common symptoms are blurred or double vision and eyes that are misaligned. Other symptoms include problems seeing out of the sides of your eyes and seeing how far things are away from you. Some people see one thing on top of another. Lazy eye (amblyopia) and squinting are also symptoms.

How is it treated?

The most common treatments are:

• Glasses. They can sometimes correct mild strabismus. Some glasses have prisms in them that may help with some symptoms.
• A temporary eye patch that you wear over the stronger eye. You may wear one all the time. Or you may wear it only during certain times, such as when you are reading. Some patches cover the whole eye. Others are put on your glasses and cover only part of an eye.
• Surgery on the eye muscles to try to align the eyes better. It may take more than one surgery. You may still need to wear glasses.
• A shot of medicine into the eye muscles.
• Eye exercises.

You may need more than one treatment. Some people don't need treatment.