If you notice that your child's eyes seem crossed or misaligned, the problem could be strabismus (misaligned eyes) or amblyopia (lazy eye). Talk to his doctor, who will probably refer you to an ophthalmologist. Fortunately, these conditions can be successfully treated if detected early.

What is strabismus?

If your toddler's eyes seem to look in different directions or not focus on the same object, he may have strabismus — a lack of coordination between the eyes. They may appear to be crossed or one may seem to drift inward, outward, or upward. The deviation may be constant or it may come and go. In young children strabismus may vary not only from day-to-day, but during the course of a day.

What causes it?

Sometimes strabismus is present at birth. The condition seems to run in families, but can also show up in children with no family history — and when that's the case, it sometimes indicates a more significant vision problem. Those who are farsighted also seem to be at higher risk.

What can be done to treat strabismus?

There is a common misconception that a child with strabismus will outgrow the condition. However, this is not true. In fact, strabismus may get worse without treatment. Any child older than four months whose eyes do not appear to be straight all the time should be examined. If your child has strabismus and it isn't treated, the brain, overtime, will learn to ignore the image from the turned eye. If the eye turning becomes constant and is not treated, it can lead to permanent reduction of vision in one eye, a condition called amblyopia or lazy eye.

The types of treatments may be used alone or in combination, depending on the type of strabismus and its cause. Strabismus that's a result of farsightedness can usually be corrected with glasses, especially if caught early. Strabismus that persists even when a child wears glasses may require surgical correction. Medication in the form of eye drops or ointment may be used, with or without glasses. Eye exercise may be recommended either before or after surgery.

What is amblyopia and what causes it?

Amblyopia, also known as lazy eye, is a vision development disorder in which an eye fails to achieve normal visual acuity, even with prescription eyeglasses or contact lenses. Amblyopia develops when the brain shuts off or suppresses vision in one eye. This can happen if your toddler's eyes are misaligned or if he can't see as well with one eye because of nearsightedness, farsightedness, astigmatism, or something that's blocking clear vision in that eye, like a cataract or a drooping eyelid. If ignored, though, amblyopia can result in permanent vision loss.

How to recognize amblyopia

Amblyopia may have no obvious signs. When only one eye is affected, a young child will not usually exhibit any unusual visual behavior. Your child's doctor should routinely test for amblyopia (as well as strabismus) by checking the eyes independently and together. It's also a good idea for you to occasionally test the vision in your child's eyes at home.

Testing for amblyopia at home
Here's a simple way to get an idea of whether your toddler's eyes are both pulling their weight:

Attract your toddler's attention by rolling a ball or dancing a stuffed animal in front of him. Cover one of his eyes and see if he follows the object with his uncovered eye. Then cover the other eye and see if he follows the object as well — and as far.

If your toddler seems to see better with one eye than the other, schedule an appointment with either your child's doctor for a vision screening test or an ophthalmologist, who can diagnose and treat the problem.

Is amblyopia treatable?

Treatment is most successful before age 5 or 6, although recent research shows that even older children may recover their vision. Treatment for lazy eye may include a combination of prescription lenses, prisms, vision therapy and eye patching. Vision therapy teaches the two eyes how to work together, which helps prevent lazy eye from reoccurring.