Strabismus Strabismus, is a condition in which a person's two eyes are not in a straight alignment with each other and occurs in approximately 4% of the United States population. There are 3 different types of strabismus: esotropia, exotropia, and vertical strabismus. Esotropia, or convergent strabismus, also referred to as crossed eyes, is a condition in which a person's eyes turn inward toward each other. Exotropia, or divergent strabismus, is a condition in which a person's eyes turn outward, away from each other. Vertical strabismus is the condition in which one's eyes are out of alignment vertically. Most commonly, strabismus is thought to be inherited. However, strabismus can also be caused by the need for eyeglasses or because of some muscle abnormality. Strabismus creates an improper binocular or stereoptic vision due to the inability of the eyes to focus together in a straight line of sight and can severely affect a person's depth perception. Treatment Glasses may be prescribed, especially for eyes that are out of focus, as they may also help to straighten the eyes. Surgery on the eye muscles is sometimes required. The goal of treatment is to restore good vision to each eye and improve binocular vision. Strabismus is sometimes seen in young children, around age 2, who were born with straight eyes which have begun to turn. If you feel this is a possibility in your young child, seek professional advice from your eyecare specialist.  Back