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Quick Facts


(Squint; Cross-Eye; Wandering Eye)


The Manual's Editorial Staff

Last full review/revision Oct 2019| Content last modified Oct 2019
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What is strabismus?

Strabismus is having one eye that looks in a different direction than the other eye. The eye may look outward (called walleye) or inward (called cross-eyes).

  • Strabismus can start in the first months of life or begin at any time in childhood

  • Strabismus is usually caused by blurry vision in one eye or by an uneven pull in eye muscles

  • Your child may have double vision or a sore neck from twisting the head to see better

  • Strabismus sometimes gets better on its own, but most children need special eyeglasses, contact lenses, or surgery

  • Without treatment, severe strabismus can cause permanent vision loss

What causes strabismus?

Strabismus is caused by:

  • Blurry vision (farsightedness)

  • Uneven pull of the muscles that control the position of the eyes, causing them to point in different directions

  • Paralysis or weakness of a nerve that controls eye movement

  • A birth defect of the eyes

Rarely strabismus is caused by a type of eye cancer that happens mostly to young children (retinoblastoma) or an eye injury.

Children are at higher risk of strabismus if they:

  • Were born too early (premature)

  • Have people in their family with strabismus

  • Have certain inherited disorders such as Down syndrome

  • Their mother used drugs or alcohol while she was pregnant

What are the symptoms of strabismus?

You may notice:

  • Your child squints a lot or covers one eye

  • Your child's eyes look like they don't point the same way

  • Your child complains of eye strain, neck strain, or double vision

Because visual signals from the two eyes don't match, your child's brain starts to ignore signals from the affected eye. This causes a form of vision loss called amblyopia. If your child's strabismus isn't corrected before about 8 years old, the vision loss may be permanent.

How can doctors tell if my child has strabismus?

Children should get regular eye exams to check for vision problems and strabismus, starting at a few months of age. Doctors will check your child's eyesight and see if both eyes look and move in the same direction.

If strabismus is caused by a weak or paralyzed nerve, doctors may do a CT scan or MRI of the brain or spine.

How do doctors treat strabismus?

If your child has strabismus, an eye doctor (ophthalmologist) can decide what treatment might be needed. Strabismus that's mild or comes and goes may not need to be treated. Treatment aims to align the eyes so they're looking in the same direction and see equally well. Depending on the cause and symptoms of your child's strabismus, doctors may:

  • Prescribe eyeglasses or contact lenses

  • Have the child do eye exercises

  • Sometimes, do surgery to loosen or tighten the eye muscles so the eyes can align

It's important to treat strabismus as it can cause amblyopia (lazy eye).

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