From birth until about 4 months of age, it is considered normal for the eyes of infants to sometimes wander or cross, according to the American Academy of Pediatrics (AAP). The reason for this is that for the first few months of life, babies’ eyes are unable to focus well, which can cause their eyes to move independently, sometimes crossing or moving inward or outward. If it continues to happen beyond 4 months of age though, you should speak with your baby’s doctor.
The misalignment of one or both eyes in, out, up, or down—a condition called strabismus —affects about 4 percent of all children, according to the National Institutes of Health (NIH). The misalignment can be constant or parents may notice it only occasionally, for instance when their child is tired or looking at an object held close to their face.
Unfortunately, strabismus will not correct itself. In fact, if left untreated it can result in permanent vision loss. Board-certified pediatric neuro-ophthalmologist, Dr. Robert Avery, explains why. “Until the age of about 6–9 years, the connection between children’s eyes and their brains are forming. When eyes are misaligned, one becomes dominant. The acuity or vision strength of the straight eye remains normal because the eye and its connection to the brain are working as they should. The misaligned or weaker eye does not focus properly and its connection to the brain is not formed correctly.”
Children with strabismus may have double vision. Their vision can also be impaired, including the loss of depth perception (stereopsis) or the ability to see in three-dimensions. For younger children who are not yet able to verbalize problems with their vision, parents may notice frequent squinting. Children with strabismus may also turn or tilt their heads in an attempt to see certain objects more clearly.
If strabismus is left untreated, the brain will eventually ignore the image of the weaker eye, causing amblyopia, also known as “lazy eye.” More than the name implies, amblyopia is permanent vision loss that cannot be corrected with glasses or contact lenses. However, if strabismus is detected early on, children can be cured and their vision can be protected through a number of safe and effective treatment options, including:
- Eye patching. Eye patches are worn over the unaffected or straight eye blocking out all light, forcing the use of the misaligned eye. Over time, consistent patching will strengthen the muscles of the weaker eye, ensure that no visual acuity is lost, and hopefully restore proper alignment to the eye. Typically, children must wear the patch 2–3 hours a day during waking hours for several years depending on the severity of the condition. In more extreme cases, patches may be worn up to six hours a day.
- Atropine drops. Just as an eye patch blocks the vision in the unaffected or straight eye, atropine drops temporarily blur out the vision in the straight eye, forcing the misaligned eye to work harder and eventually realign.
- Glasses. In some cases, the use of glasses helps maintain the alignment of the eyes, ensuring that the connection between the eyes and the brain is forming correctly.
- Surgery. In cases where patching, drops, and glasses are not able to realign the eyes, eye muscles may be surgically strengthened (shortened) or weakened (elongated) to restore proper alignment.
The effectiveness of these treatment options depends on the severity of a child’s condition and how quickly it is recognized and addressed. The good news is that if it is treated early, strabismus can be cured and permanent vision loss can be prevented.