Ophthalmology => Strabismus
Strabismus, abnormal condition, sometimes called cross-eye, in which the muscles of the eye prevent normal binocular vision. The cause of the defect may be paralysis or weakness of one or more of the six muscles that control eye movements, or faulty coordination of the brain and eye, or infection of nerves connecting the eye muscles. Some forms of strabismus may be corrected by the use of glasses. Surgery is sometimes employed to shorten part of the affected muscles and to reposition the eye for an improved appearance.