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Strabismus and Amblyopia: What Parents Need to Know

10/30/23 Leila M. Khazaeni, MD, Loma Linda University School of Medicine;

As children grow and develop, some parents may notice that their eyes begin to point in different directions and become misaligned. This condition is known as strabismus, and it’s relatively common. About 3% of children have strabismus.

Early signs of strabismus include crossing or drifting of the eyes. This can occur randomly throughout the day, or it can be more common when a child is tired or distracted. Squinting with one eye in bright sunlight is another warning sign, and it’s also why some people refer to the condition as “squint.” One way to gauge the severity of strabismus in older children is to ask if their friends are noticing it. If they are, that means it’s happening more frequently and isn’t controlled.

Parents should not delay in making sure children displaying signs of strabismus are seen by a doctor. Here are a few things parents and patients should know if they notice a misalignment in their children’s eyes.

1. There are several types of strabismus

Strabismus is the medical term for misalignment of the eyes. There are many different types, and most people know the condition by its more informal names like crossed-eyed or wandering eye. Some types are characterized by inward turning of the eye (esotropia or cross-eye) and some by outward turning of the eye (exotropia or walleye). Other types are characterized by upward turning of the eye (hypertropia) or downward turning of the eye (hypotropia).

Strabismus most commonly develops in early childhood. Causes vary, often depending on age, and include a family history of the condition, genetic disorders or a traumatic injury to the face or head. In some children, excessive farsightedness is often a cause, and systemic diseases such as thyroid conditions are a more common cause in adults.

2. Strabismus can lead to amblyopia, known as lazy eye

There’s often confusion between strabismus and amblyopia. All types of strabismus can lead to amblyopia, also known as lazy eye. Amblyopia is a decrease in vision that occurs because the brain ignores the image received from an eye and can be caused by misalignment of the eye. If left untreated, about 50% of children with strabismus have some vision loss due to amblyopia.

3. Strabismus does not go away on its own

If a child is showing signs of misalignment in their eyes, parents may want to wait and see if the condition goes away on its own. The reality is, people do not grow out of strabismus. It will continue to impact an individual’s vision until it’s treated. Anyone displaying signs of strabismus should be seen by a doctor promptly to determine the right treatment plan and avoid potential vision loss.

4. Strabismus is most often treated with surgery

In most cases, treatment entails outpatient surgery to either weaken or strengthen the eye muscles to align the eyes. In some cases, full-time glasses are recommended. Depending on the severity and progression of the condition, doctors may first work to equalize vision and correct amblyopia that has occurred. This can be achieved through eye patches or drops that strengthen the vision in the weaker eye. These are only treatments for amblyopia (decrease in vision), not strabismus (misalignment).

Amblyopia must be treated in childhood, as a child’s visual system develops. Many people believe strabismus must also be treated in childhood. That’s not true. Many adult patients have surgery later in life with successful outcomes. Yet even with treatment, strabismus is a lifelong condition. Success rates with surgical repair of strabismus can be greater than 80%. About 20% of children need another surgical procedure.

5. Every child should have regular vision screenings

Children should be examined periodically to measure vision and to detect strabismus starting at a few months of age. Traditional screening methods or photo screenings are both effective.

There is a significant social component to strabismus. Research has found that the condition has been shown to impact an individual’s performance in job interviews and social situations. It’s another important reason for parents to watch for signs of strabismus and address any concerns early in addition to regular vision screenings and pediatric care.

For more on strabismus, visit the Manuals page on the topic.