Amblyopia, more commonly referred to as lazy eye, is a disorder in which the visual acuity in one or both eyes is reduced due to abnormal visual development during infancy and early childhood. In amblyopia, the brain favors the visual signal from the stronger eye and ignores the weaker eye, often causing it to wander inward or outward. If left untreated, permanent vision loss in the lazy eye can result. This loss of vision can range from mild to severe.
Signs and Symptoms
In a baby, the first sign of amblyopia is an eye that turns inward or outward. This may be observed all the time or noticed only when your baby tries to focus on an object. Infants with amblyopia also may exhibit difficulty with depth perception and experience delays in hand-eye coordination. Some babies with lazy eye demonstrate an aversion to having their stronger eye covered because they recognize that they cannot see as well with their amblyopic eye.
Causes
According to Lighthouse International, 2 to 5 percent of children have amblyopia. Many of the causes appear to have a genetic component. The most common reason for amblyopia is strabismus, an imbalance in the eye muscles causing the eyes to cross in or turn out. The child's brain favors the eye that is able to focus straight ahead, and the vision in the weaker eye does not develop properly. Another cause is a large disparity in eyeglass prescriptions between the two eyes. Similar to strabismus, the brain favors the eye that focuses more easily and the other eye becomes lazy. A rarer cause of amblyopia is a structural abnormality of the baby's eye, such as a congenital cataract or droopy eyelid.
Diagnosis
Early detection of lazy eye in a baby is critical for vision development. Your infant's pediatrician screens for eye problems at his or her well-visits during the first few years of life. If you or your child's doctor notice any signs of a lazy eye, an optometrist or ophthalmologist can perform a more thorough examination to rule out other eye conditions and begin treatment if necessary.
Treatment
Treatment of lazy eye often involves wearing prescription glasses or contact lenses. Sometimes corrective eyewear is all that is required to take care of the condition. Other cases are treated by patching the better-seeing eye for part of the day. This strengthens the weaker eye by forcing the baby to use it. Surgery may be required around age 1 if your baby's eye turns inward or outward to a large degree. Surgery also may be necessary for an infant with congenital cataracts or droopy eyelids that prevent vision from developing properly.
