Strabismus is a problem with the alignment of the eyes. One or both of the eyes are turned in, out, up, or down. Strabismus is most common in children but may occur in adults. It can lead to permanent vision loss if it is not detected and treated in a timely manner.

Appearance of Strabismus
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There are two types:

  • Constant strabismus—the eye turns all the time
  • Intermittent strabismus—the eye turns only some of the time, like in times of stress, illness, concentration, or when tired

Strabismus is caused by a lack of coordination between the muscles in the eyes. This can happen due to:

  • Problems, imbalances, or injuries of the muscles that move the eyes
  • Nervous system disorders that affect vision, such as:
    • Problems or injury of the nerves that control the eye muscles
    • Tumor in or near the eye or brain
    • Strokes or bleeding in the brain
    • Increased pressure in the brain
    • Myasthenia gravis