What is Strabismus?

Strabismus, also known as crossed or turned eye, is the medical term used when the two eyes are not straight. It is a visual defect in which the eyes are misaligned and point in different directions. One eye may look straight ahead, while the other eye turns inward, outward, upward or downward. The eye turn may be constant, or it may come and go. The turned eye may straighten at times, and the straight eye may turn.

What Causes Strabismus?

The exact cause of strabismus is not fully understood. Most commonly, a tendency to have some type of strabismus is inherited. Occasionally, the condition is due to some muscle abnormality. To line up and focus both eyes on a single target, all of the muscles in each eye must be balanced and working together. In order for the eyes to move together, the muscles in both eyes must be coordinated. The brain controls these eye muscles. Very rarely, strabismus may be secondary to a serious abnormality inside the eye, such as a cataract or tumor.

What are the Symptoms of Strabismus?

  • Turned or crossed eye
  • Squinting
  • Head tilting or turning
  • Double vision (in some cases)
Strabismus (turned or crossed eye)

How is Strabismus Detected?

Strabismus can be detected during an eye exam. It is recommended that all children between 3 and 3 1/2 years of age have their vision checked by their pediatrician, family practitioner, or an individual trained in vision assessment of preschool children. If there is a family history of strabismus or amblyopia, or a family history of wearing thick glasses, an ophthalmologist should check vision even earlier than age 3.Notice the asymmetrical light reflection.

Who is Most at Risk?

Strabismus is a common condition among children. Strabismus is especially common among children with disorders that may affect the brain, such as Cerebral Palsy, Down Syndrome, Hydrocephalus, Brain Tumors, and Prematurity.

How is Strabismus Treated?

Treatment usually includes patching the eye that is always straight to bring the vision up to normal in the turned eye. Glasses may be used, particularly for eyes that are out of focus. Glasses and special drops (phospholine iodide) may also help straighten the eyes. The success of treatment may depend on how quickly treatment is begun. If treatment is unduly delayed, vision may not be restored. This type of legal blindness can be completely prevented. Do not delay if your child has strabismus. Seek professional advice from your family doctor.

How can Strabismus Be Prevented?

Any case of poor vision in one eye in a child may lead to strabismus. To detect poor vision in one eye or the other, parents should take children for regular eye examinations. The American Academy of Ophthalmology recommends regular eye exams from birth, then at 6 months, 3 years, and 5 years old. However, if you or your child notices problems with his or her vision, visit the eye doctor or pediatrician immediately.

This document is provided for informational purposes only. Please consult an eye care professional about symptoms that may require medical attention and may or may not be covered by your medical plan and/or routine vision plan.

Sources: American Academy of Ophthalmology (AAO) -