What is Amblyopia?

Amblyopia is poor vision in an eye that did not develop normal sight during early childhood. It is sometimes called "lazy eye." When one eye develops good vision while the other does not, the eye with poorer vision is called amblyopic. Usually, only one eye is affected by amblyopia, but it is possible for both eyes to be amblyopic.


What Causes Amblyopia?

Amblyopia, has many causes. Most often it results from either a misalignment of a child's eyes, such as crossed eyes, or a difference in image quality between the two eyes (one eye focusing better than the other). In both cases, one eye becomes stronger, suppressing the image of the other eye. If this condition persists, the weaker eye may become useless.

What are the Symptoms of Amblyopia?

Unless an obvious abnormality is present (e.g. crossing of the eyes, a droopy eyelid, or a dense cataract), amblyopia may have no obvious signs. When only one eye is affected, a young child will not usually complain of blurred vision.

How is Amblyopia Detected?

Amblyopia is detected by finding a difference in vision between the two eyes or poor vision in both eyes. Since it is difficult to measure vision in young children, your ophthalmologist often estimates visual acuity by watching how well a baby follows objects with one eye when the other eye is covered.

Who is Most at Risk?

Children under nine years of age whose vision is still developing are at highest risk for amblyopia. Generally, the younger the child, the greater the success of treatment. An older child may not achieve normal vision with treatment.

How is Amblyopia Treated?

To correct amblyopia, a child must be made to use the weak eye. This is usually done by patching or covering the strong eye, often for weeks or months. Even after vision has been restored in the weak eye, part-time patching may be required over a period of years to maintain the improvement. Glasses may be prescribed to correct errors in focusing. If glasses alone do not improve vision, then patching is necessary.

How can Amblyopia Be Prevented?

Amblyopia can be prevented through early diagnosis and treatment. Without treatment, an amblyopic eye may never develop properly and even become blind. The American Academy of Ophthalmology recommends regular eye exams from birth, then at 6 months, 3 years, and 5 years old. However, if you or your child notices problems with his or her vision, visit the eye doctor or pediatrician immediately.

This document is provided for informational purposes only. Please consult an eye care professional about symptoms that may require medical attention and may or may not be covered by your medical plan and/or routine vision plan.

Sources: American Academy of Ophthalmology (AAO) -