Also referred to as crossed-eyes or squint, strabismus1 is a visual disorder that occurs when the muscles controlling each eye do not work properly, resulting in asymmetrical movement of the eyes. Individuals with strabismus may have one eye that looks straight ahead, while the other eye points downwards, upwards, inwards or outwards.
Strabismus often begins in early childhood and requires prompt treatment to prevent permanent vision problems or vision loss. Not only can strabismus affect a child’s vision permanently, but it can also result in feelings of shame and embarrassment for the child. If you detect any abnormal movements or misalignment between your child’s eyes, it is important to seek help immediately.
Around 4% of American children suffer from strabismus, making it one of the most common vision disorders. As such, it is recommended that all children be screened for strabismus during the preschool years.
To diagnose strabismus, our ophthalmologist will examine the patient's eyes and go over any existing symptoms. Common symptoms of strabismus include:
In some instances, the misalignment may be very slight and the child may suffer from the common side effects of strabismus, making detection by a non-medical professional very difficult. For this reason, it is recommended that children between 3 and 3 ½ undergo an eye exam with Dr. Semaan, our optometrist, at our Huntington Beach, Orange County office. In addition, if there is a family history of strabismus or amblyopia, the child's vision should be checked even sooner.
Infantile esotropia2 develops between birth and six months of age. It is the most common type of strabismus among infants and causes one or both eyes to turn inwards. A baby with infantile esotropia typically cross fixates, which means that they use their left eye to look towards the right and vice versa. While researchers have not determined an exact cause of infantile esotropia, they have identified a number of risk factors, which include family history, prematurity, complications during pregnancy and following the birth, and being male.
When excessive inward turning of one or both eyes first occurs around 2 years of age, accommodative esotropia may be diagnosed. This type of strabismus is caused when the accommodative (focusing) system does not integrate properly with the eye alignment system, causing an inward turn of the eyes. Accommodative esotropia3 can be treated with eyeglasses or vision therapy and does not require surgery to correct.
In exotropia4, either eye turns outwards when the child is focusing on distant objects, near objects, or both. This condition can be chronic or may only occur occasionally (for example, when the child is tired or sick). It is also be associated with a squint in one eye when exposed to bright sunlight.
More commonly known as "lazy eye," amblyopia5 occurs when the brain fails to receive a strong signal from the eye via the optic nerve. Nearly half of all children who suffer from strabismus will go on to develop amblyopia. Because the eyes often appear normal, permanent damage can occur while the problem goes undetected. It is estimated that amblyopia affects between 1 and 5 percents of the population, so an early screening in childhood is critical to prevent permanent damage. If left uncorrected, poor vision or blindness may occur in the affected eye, leading to overall impairment in adulthood. Treatment for lazy eye typically involves impairing the strong eye (through a patch or special eyeglasses) to encourage the weaker eye to grow stronger.
In some instances, the eyes of infants only appear to be crossed. If these children are not diagnosed with strabismus, their condition is referred to as pseudostrabismus6. As a child's facial features develop, the appearance of pseudostrabismus will improve and eventually resolve on its own. Strabismus, on the other hand, will not improve without treatment and may continue to worsen.
If strabismus is suspected, our ophthalmologists will first seek to determine whether there is a true visual disorder or if it is pseudostrabismus. One test our doctor will perform is the Corneal Light Reflex test, which allows the doctor to examine how light is reflected in the child's eyes. With pseudostrabismus, the light will be evenly reflected in both pupils. With strabismus, the light will appear in different places for each eye.
It can be difficult for a parent or even a pediatrician to distinguish between pseudostrabismus and true strabismus. For this reason, it is important to have your child examined by one of our experienced ophthalmologists if there is any suspicion of a visual disorder.
The primary goal in treating strabismus is to straighten the eyes and restore binocular (two-eyed) vision. The type of treatment required depends upon the type and severity of the child's strabismus.
In some cases, special eyeglasses can be used to correct misaligned vision. Patients with accommodative esotropia may be prescribed eyeglasses that reduce the focusing effort and eventually straighten the eyes. Bifocals may also be required to assist with focusing on objects in the near range of vision. Glasses can also be used to correct some instances of exotropia, especially when combined with visual exercises, patching or the use of special prisms.
When eyeglasses and other visual therapies fail to straighten the eyes, surgery may be necessary. Surgery to treat strabismus typically involves correcting unbalanced eye muscles or removing a cataract, if this is determined to be the cause of the misalignment.
During surgery, which may be performed on one or both eyes, the eye surgeon will make a tiny incision in the eye to access the eye muscles. The eye muscles will then be carefully detached from and repositioned to the wall of the eye. When performed on children, general anesthesia is required. Recovery time is quick and most children are able to resume normal activities within a few days.
After surgery, the child may or may not be required to continue wearing glasses. While strabismus surgery is generally safe and effective, it cannot be used to treat all forms of strabismus. In many cases, our doctor will try more conservative treatment before recommending surgery.
If your child has been diagnosed with strabismus or you are concerned about crossed-eyes, please contact our office today. Our experienced eye doctors will help you determine the best course of action to restore your child’s vision.
1 What Is Adult Strabismus? Available: https://www.aao.org/eye-health/diseases/what-is-strabismus
2 Strabismus: Infantile Esotropia. Available: https://www.aao.org/disease-review/strabismus-infantile-esotropia
3 WHAT IS ACCOMMODATIVE ESOTROPIA? Available: https://aapos.org/glossary/accommodative-esotropia
4 What Is Exotropia? Available: https://www.healthline.com/health/exotropia
5 Lazy eye (amblyopia). Available: https://www.mayoclinic.org/diseases-conditions/lazy-eye/symptoms-causes/syc-20352391
6 What Is Pseudostrabismus?. Available: https://www.aao.org/eye-health/diseases/what-is-pseudostrabismus
Written by Dr. Shah
I've had laser assisted cataract surgery with clear upgrade performed on both eyes. The rapidly worsening astigmatism and the far-sightedness I've had for so long were corrected and my measured vision in each eye is now 20/20. For the first time in almost 25 years, I am not wearing bifocals. In fact, I'm not wearing corrective lenses at all, even for reading! I'm very happy with the service, communication & surgical results from Dr. Shah and everyone at Beach Eye Medical Group. BTW, all the staff takes time to answer any questions and concerns and as the day progresses, sometimes the wait time extends beyond the scheduled appointment time. Once you're seen by any of the staff, all your questions will be answered. If you or someone in your care is pinched for time, ask for an early appointment.