Strabismus

Strabismus, or crossed eyes, is a misalignment of the eyes. The eyes are not lined up with each other and are unable to point at the same object together. The condition occurs in about 4% of children, and many adults suffer from it as well.

Sometimes incorrectly referred to as a lazy eye, strabismus is also known as:

Crossed eyes
Wandering eyes
Wall-eyed

Types of Strabismus

Strabismus is classified according to the direction the eye is turned. The most common types of strabismus are:

Inward turning, or esotropia
Outward turning, or exotropia
Upward turning, or hyperopia
Downward turning, or hypotropia

Causes of Strabismus

Strabismus may be caused by the following:

Congenital (present from birth)
Eye injury
Diabetes
Tumor
Retinal damage
Farsightedness
Stroke
Cranial nerve palsy
Other medical conditions

Symptoms of Strabismus

Strabismus may occur all the time or appear intermittently, usually when the person is tired, ill or concentrating on near vision objects. Symptoms of strabismus include:

Loss of depth perception
Double vision
Loss of vision

Diagnosis of Strabismus

After a thorough medical examination of the eye, the doctor will test for strabismus using the Hirschberg test to examine the reflection of light in each eye. If the eye is not properly aligned, the reflection will not be seen in the same place in each eye. Other diagnostic tests that may be performed include:

Retinal exam
Visual acuity exam
Cover test

Treatment of Strabismus

The goal, in the treatment of strabismus, is to preserve vision. For children, early treatment is best, preferably before the age of six. Older patients can be helped as well; it's never too late to seek treatment.

Advanced cases of strabismus are treated with a combination of therapy, including:

Prescription eyeglasses
Vision therapy
Surgery
Prism therapy
BOTOX® injections

Strabismus may manifest at first as double vision. Without treatment, strabismus can lead to:

Visual impairment
Loss of binocular vision
Blindness in the weaker eye