Alternative Names

Crossed eyes; Esotropia; Exotropia; Hypotropia; Hypertropia; Squint; Walleye; Misalignment of the eyes; Comitant strabismus; Noncomitant strabismus

Definition of Strabismus

Strabismus is a disorder in which the two eyes do not line up in the same direction, and therefore do not look at the same object at the same time. The condition is more commonly known as “crossed eyes.”

Causes, incidence, and risk factors

Six different muscles surround the eyes and work “as a team” so that both eyes can focus on the same object.


Symptoms of strabismus may be present all the time, or only when you are tired or sick.

Signs and tests

A physical examination will include a detailed examination of the eyes. Tests will be done to determine how much the eyes are out of alignment.


The first step in treating strabismus is to prescribe glasses, if needed.

Expectations (prognosis)

After surgery, the eyes may look straight but vision problems can remain.


David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Franklin W. Lusby, MD, Ophthalmologist, Lusby Vision Institute, La Jolla, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A. – 7/28/2010

Crossed eyes

ADAM Medical Encyclopedia

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