What Is Esotropia?

A muscle disorder that causes crossed eyes

Table of Contents
View All
Table of Contents

Esotropia is a type of strabismus, a disorder in which the eyes aren't fully aligned and the affected eye(s) turn inward. It typically occurs in babies and children, but it can affect adults too. Esotropia is also associated with certain health conditions, including premature birth.

An infant’s crossed-eye appearance isn't always cause for concern. That said, when esotropia appears in children after 4 months of age, it rarely resolves on its own. At that point, they should be seen by a pediatric eye specialist. Surgery to correct esotropia may be needed.

This article explains esotropia, its possible causes, and how it is diagnosed and treated. It also lists some of the health conditions that may increase the risk of esotropia in both children and adults.

A young girl with a lazy eye
Pholdar nine / Getty Images

Causes in Children

In babies less than four or five months of age, intermittent crossing is usually normal and is just a sign of learning how to use the eyes together as a system. Beyond that, esotropia is usually a sign of an abnormal development of the binocular system that develops in the brain. However, there are other causes.

Some babies and ethnic groups may have pseudo-strabismus, which usually goes away as the infant develops and the eyes begin to appear normal. With this condition, kids have epicanthal folds that make the eye look like it turns in slightly because the bridge of the nose is not fully developed.

How your child's esotropia will progress, and what kind of treatment they need, will depend on the type of esotropia and its cause.

Congenital Esotropia

Infants aren't necessarily born with congenital esotropia, despite the name. But it does emerge within the first six months of life in an otherwise neurologically healthy child. Its exact cause is unknown, but may be due to a nerve condition, or atypical brain development that affects motor function.

The size of the deviation, or eye turn, tends to be significant and noticeable by four months of age. Infants with congenital esotropia don't usually have a large amount of farsightedness or nearsightedness. The dysfunction is in the development of their binocular system, or the ways that eyes work together, and affects depth perception (stereopsis).

Congenital esotropia is typically corrected with surgery. Because esotropia may be linked to a motor dysfunction, some experts believe it should be done as early as possible in infancy.

One study of 216 children who had congenital esotropia found it to be a risk factor, leading to additional surgery later, if kids had their first corrective surgery after the age of 2.

Surgery also may be used to improve the child's appearance.

Accommodative Esotropia

Accommodative esotropia accounts for more than half of all esotropias in childhood. There are three different types, with symptoms occurring as late as age 7, but the average is about 2 1/2 years. Many cases are believed to be genetic, though some are linked with trauma or an illness.

A basic problem lies with the two systems that control our eye muscles and the amount our eyes focus. The accommodative, or focusing, system allows our eyes to change power and focus so that objects remain clear no matter the distance.

The binocular alignment system controls how our eyes work together. When we look far away, our eyes are straight. When we look at something very close, our eyes turn in and increase their focus.

When a child has significant uncorrected farsightedness, they have to focus a great deal to compensate. When they focus this much, the binocular and focusing systems begin to get mixed signals. Usually, one eye will turn in as a result.

Many cases of accommodative esotropia are treated with special eyeglasses, although surgery may be needed.

Does Eye Strain Cause Esotropia?

Eye strain may be a feature of some types, including accommodative esotropia. Another type, called acute acquired comitant esotropia (AACE), can occur more suddenly in children and adults. One small study found some cases of AACE emerged during the COVID-19 pandemic, as students did "near work" on smartphones and laptops during social distancing lockdowns.

Causes in Adults

Esotropia in adults is most often caused by a "lazy eye" that was never treated when they were younger. This condition follows from strabismus and, left untreated, may lead to a loss of vision.

However, esotropia also may emerge suddenly in adulthood because of other health conditions, some of which can be serious.

Some of the medical conditions that may lead to esotropia in adults include:

Depending on the cause, esotropia in adults can be corrected with special glasses or through esotropia surgery. However, surgery cannot correct depth perception because this function of the eye doesn't develop beyond childhood.

Complications

Some conditions are complications of esotropia and their symptoms may overlap. They include:

  • Amblyopia, a condition that occurs when one or both eyes never see a clear image. If the image is never seen clearly for a long enough period of time, permanent vision loss may develop. After age 14, the brain and nervous system become hard-wired and it is difficult to improve vision back to normal. Therefore, early treatment is critical.
  • Lack of true depth perception, which relies on distance between the eyes. When one eye is turned in or being suppressed, the person with esotropia only sees with one eye. People with esotropia have a difficult time with 3-dimensional viewing, which may affect sports or job opportunities.  

Frequently Asked Questions

  • Is it normal for a baby's eyes to cross?

    Yes, up until ages 4 to 5 months, babies cross their eyes from time to time as their binocular vision develops. But if your baby’s eyes always appear crossed, talk to the pediatrician. It could be esotropia, a sign of vision problems. 

  • Is esotropia the same as lazy eye?

    Sometimes. Esotropia occurs when one or both eyes turn inward toward the nose. When amblyopia or lazy eye turns inward, it is esotropia. When it turns outward, it’s known as exotropia. 

  • Can esotropia be corrected?

    Yes, esotropia or cross-eyes can usually be corrected. Glasses with bifocal or prism lenses may be used to correct vision. When esotropia is caused by a lazy eye, an eye patch is often used on the stronger eye to strengthen the weaker eye. Surgery is also sometimes needed, especially in children with infantile esotropia. 

  • What is the difference between esotropia and esophoria?

    Both esotropia and esophoria involve a "cross-eyed" misalignment of the eye gaze. With esophoria, however, a person can more easily refocus the eye and control their vision when an eye drifts.

12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Bhate M, Flaherty M, Martin FJ. Timing of surgery in essential infantile esotropia - What more do we know since the turn of the century? Indian J Ophthalmol. 2022 Feb;70(2):386-395. doi:10.4103/ijo.IJO_1129_21.

  2. American Association for Pediatric Ophthalmology and Strabismus. Esotropia.

  3. American Association for Pediatric Ophthalmology & Strabismus.Pseudostrabismus.

  4. American Academy of Ophthalmology. Infantile Esotropia.

  5. Rajavi Z, Sabbaghi H, Torkian P, Behradfar N, Yaseri M, Feizi M, et al. The relationship between abduction deficit and reoperation among patients with infantile esotropia. Int J Ophthalmol. 2018 Mar 18;11(3):478-483. doi:10.18240/ijo.2018.03.19.

  6. American Academy of Ophthalmology. Strabismus: Accommodative Esotropia.

  7. Neena R, Remya S, Anantharaman G. Acute acquired comitant esotropia precipitated by excessive near work during the COVID-19-induced home confinement. Indian J Ophthalmol. 2022 Apr;70(4):1359-1364. doi:10.4103/ijo.IJO_2813_21. 

  8. American Association for Pediatric Ophthalmology & Strabismus. Amblyopia.

  9. Erkan turan K, Kansu T. Acute Acquired Comitant Esotropia in Adults: Is It Neurologic or Not?. J Ophthalmol. 2016;2856128. doi:10.1155/2016/2856128

  10. Kim DH, Noh HJ. Surgical outcomes of acute acquired comitant esotropia of adulthood. BMC Ophthalmol. 2021 Jan 18;21(1):45. doi:10.1186/s12886-020-01793-3.

  11. University of Michigan Kellogg Eye Center. Esotropia in Adults.

  12. Michigan Medicine. Kellogg Eye Center. Esotropia.

Additional Reading
  • Clinical management of binocular vision. Third edition. Shieman, M., Wick, B. Lippincott Williams & Wilkins, ISBN-13 978-07817-7784-1

By Troy Bedinghaus, OD
Troy L. Bedinghaus, OD, board-certified optometric physician, owns Lakewood Family Eye Care in Florida. He is an active member of the American Optometric Association.