Misaligned Eyes (strabismus)
With strabismus, the eyes are not aligned. Strabismus is quite common and occurs in about 4% of children. One eye may gaze straight ahead while the other eye turns inward, upward, downward, or outward. When an eye turns inward, the child has “crossed” eyes (esotropia).
Common Causes for Esotropia, or “Crossed Eyes”
There are two common causes for esotropia. Some children are born with crossed eyes (or develop it shortly after birth), and in this situation the muscles are too tight. Treatment for this most commonly involves surgery on the eye muscles, generally performed prior to the age of 2.
The second most common cause for esotropia is excessive farsightedness. This problem can be present at birth, but most commonly occurs between the age of 2 and 6 years. This type of esotropia is corrected with glasses.
When an eye turns outward, the child has exotropia. Exotropia may be present from birth, but most commonly is seen in children 2 to 7 years of age. Generally the eyes turn out on rare occasions at first but with time more frequent outward turning of the eyes is noted. Children with exotropia occasionally squint one eye when exposed to bright sunlight. The treatment for large amounts of exotropia is usually eye muscle surgery.
Children with misaligned eyes will generally discontinue using the “turned eye” so they do not have double vision. Children with strabismus should have a careful examination by an ophthalmologist because untreated strabismus may lead to a lazy eye (amblyopia) or loss of depth perception. Rarely, strabismus may indicate a more serious condition, such as cataract or eye tumor (retinoblastoma).
Falsely Misaligned Eyes (pseudostrabismus)
Sometimes infants appear to have crossed eyes, yet the eyes are truly straight. The cause for pseudostrabismus is presence of a wide nasal bridge or extra folds of skin between the nose and the inside of the eye that make the child have a cross-eyed appearance. Most children outgrow this problem, but you should contact your physician for an examination. Your pediatrician can tell whether a child has misaligned eyes or just pseudostrabismus, but in some instances, a visit to an ophthalmologist is necessary for further tests.