Strabismus

Strabismus or misaligned eyes is a common condition in children that can cause decreased vision or amblyopia, poor depth perception, and social difficulties at school or home. If you or your child’s pediatrician are concerned about strabismus in your child, highly skilled pediatric ophthalmologist, Elena Nguyen, MD, at ENvision Eye Care in Foster City, California, offers expert diagnosis and treatment of strabismus.  Call ENvision Eye Care or request an appointment online today for a strabismus evaluation.

What is strabismus?

Strabismus refers to the misalignment of one or both eyes and can be classified by the direction of the misalignment.  Common types of strabismus include esotropia (i.e. inward crossing of one or both eyes), exotropia (i.e. outward drifting of one or both eyes), or hypertropia (upward drifting of one eye compared to the other). Strabismus can also be classified by its causes.

What causes strabismus?

Strabismus can be caused by a weakness or “palsy” of any one of the three cranial nerves (i.e. III, IV, or VI) that are responsible for eye movement.  These types of strabismus can be called a third nerve (III) palsy or superior oblique (IV) palsy, depending on the cranial nerve involved.

Accommodative esotropia is a type of strabismus where a child’s eyes will cross inward and is related to farsightedness.  Infantile/ congenital esotropia or exotropia are types of strabismus where one or both eyes have had a tendency to cross inward or drift outward since birth.  These types of strabismus are usually due to an abnormality of the pathways between the brain and the eye muscles that control eye movement.

Strabismus often occurs in children who are completely healthy and developmentally normal.  However, children with disorders that affect the brain such as cerebral palsy and Down syndrome are more likely to develop strabismus.

Strabismus can also be caused by trauma to the brain, the nerves that control eye movement, or the eye muscles themselves.

How is strabismus related to poor vision?

When one eye is misaligned, the brain receives 2 different visual images from each eye and will often ignore or shut off the eye that is misaligned to avoid double vision.  When this happens, the misaligned eye loses its ability to develop vision.  The reverse can be true as well, in that a poorly seeing eye (e.g. due to a cataract or corneal scar, etc.) can become misaligned due to lack of visual input to that eye.

How is strabismus diagnosed?

Strabismus is diagnosed by a comprehensive eye exam which includes a sensorimotor exam to assess eye alignment and depth perception.  These are performed by an experienced pediatric ophthalmologist such as Dr. Nguyen.  See “Pediatric Eye Exam” for more information.

How is strabismus treated?

Treatment differs depending on the type of strabismus and includes eye glasses, eye exercises, prism therapy, and/ or eye muscle surgery.

If there is concern for strabismus in your child, schedule an eye exam with Dr. Nguyen by calling ENvision Eye Care or booking an appointment online today.