Amblyopia

Reduced vision in one (or sometimes both) healthy eye(s) that is often associated with crossed eyes, a large difference in the degree of nearsightedness, farsightedness or astigmatism between the two eyes, childhood cataract, or other conditions that cause one eye to be favored and the other ignored by the brain. The disorder is usually not correctable by eyeglasses or contact lenses, generally develops by the time a child is age six and, if left untreated, will interfere with normal development of the child's vision.