Amblyopia, or as it is commonly called lazy eye, is a condition in children where vision does not usually develop properly in one eye. If left untreated, a child’s vision will not develop properly in the affected eye.

What causes amblyopia?

Amblyopia usually begins when one eye has a much better focus than the other. For example, one eye may have a lot of astigmatism, while the other may not. When a child’s mind is confronted with a blurred and clear image, it begins to ignore the blurred image. If this continues for months or even years in a small child, vision in the blurred eye will deteriorate.

Another cause of amblyopia is strabismus, which means that one eye turns inward or outward. This prevents the eyes from focusing on an image and can cause diplopia. To combat this, the child’s brain chooses to ignore the image from the deviating eye, causing deterioration of vision in that eye. This misalignment of the eyes leads some people to the condition of “lazy eye”.

How is the diagnosis made?

All children should be screened before school age. Your child’s doctor or school vision program will check for three aspects of your child’s eye health:

the eyes allow the light to reach the end
both eyes see equally well
the eyes move normally.

Doctors recommend a test every 6 months, every 3 years, and then every two years during the school years. A family history of amblyopia is a risk factor for the condition. Early diagnosis and treatment are the keys to the best visual result.

How is it treated?

The most common treatment for amblyopia is to force the brain to start using the “evil” eye. This is done by first correcting any major problems in this eye and then placing a patch over the “good” eye. It is very important that your child wears the patch carefully, as this will ultimately improve vision. It may take weeks or months for vision to improve.