Abnormal visual conditions in children that parents often worry about are mostly related to nearsightedness, farsightedness, or astigmatism. However, in reality, there are other abnormalities that need to be carefully monitored as well, which is “abnormal eye muscle condition”. This condition may be associated with refractive errors and can further worsen the child’s vision. Therefore, understanding the story of abnormal eye muscle conditions is important and should not be overlooked by parents, so they can recognize the symptoms and take their child to see a doctor for timely treatment.
What is abnormal eye muscle in children and why does it occur?
The eye muscle is an important part of the eye responsible for controlling eye movement in all directions. There are 6 muscle groups per eye, totaling 12 muscles for both eyes. Each muscle works together to allow us to move our eyes left, right, up, and down efficiently. Abnormalities in children’s eye muscles occur when the nerves supplying each muscle malfunction, causing muscle weakness. This leads to abnormal eye movement, resulting in “crossed eyes” or “strabismus.” It can also be caused by fibrous tissue pulling the muscles, leading to abnormal eye movement. However, abnormal eye movement or strabismus may also result from brain abnormalities, so a detailed diagnosis is necessary to find the true cause and provide appropriate treatment.
What diseases can abnormal eye muscles in children cause?
Abnormal eye muscle condition in children, or strabismus, can be classified into several types as follows:
- Comitant strabismus: The child can move their eyes well in all directions but the eyes appear crossed in every direction, for example, when looking left or right, the eyes still appear crossed. In some cases, it may be intermittent, with good eye movement most of the time but strabismus appearing at times when control is lost.
- Incomitant strabismus: The eyes move normally in some directions but appear crossed in others. This may be caused by weak eye muscles, known as palsy, or by fibrous tissue restriction, leading to abnormal eye movement in certain directions.
How to observe and be sure that your child has strabismus due to abnormal eye muscles?
Abnormal eye muscle condition or strabismus may occur intermittently. Therefore, careful observation is important. Adults can usually notice it themselves because they may experience double vision as a warning sign. However, for children, if the strabismus is not obvious, it is difficult to detect because they may not be able to tell us, especially if the condition has been present since birth. Therefore, eye health check-ups are the best preventive method. One simple way to preliminarily observe and assess whether a child has abnormal eye muscles or strabismus is by performing the Corneal Light Reflex Test or “taking a photo with flash” using a regular mobile phone camera. This test checks if the light reflection is centered on the pupil. If the light reflection is off-center, it indicates that the eye may have an abnormal eye muscle condition, and the child should be taken to a doctor for a detailed examination.
Why should you take your child to see a doctor immediately if you notice strabismus?
If you notice your child has strabismus, even if only occasionally, parents should be suspicious and not delay taking the child for a medical diagnosis. Strabismus may not only be caused by abnormal eye muscles but can also result from cataracts or retinal tumors. It can also be part of amblyopia in children, which may cause loss of 3D vision and normal sight. Early medical examination is beneficial for effective treatment planning.
Additionally, strabismus may be associated with refractive errors. For example, esotropia (inward turning) is often linked to farsightedness, while exotropia (outward turning) may be related to nearsightedness or astigmatism. Therefore, seeing a doctor helps detect and treat refractive errors early. If the condition is not severe, wearing glasses alone can correct strabismus because clear vision reduces the need to strain the eyes, allowing the eye muscles to return to normal and the strabismus to improve.
How to treat strabismus and abnormal eye muscles in children?
Initially, when parents bring their child to see a doctor after noticing strabismus, the doctor will proceed with examination, diagnosis, and treatment in the following steps:
- Carefully check if the strabismus is real or pseudo-strabismus, which can be caused by wide nasal wings covering the inner eye corner, making the white of the eye less visible and giving a false impression of strabismus.
- If real strabismus is confirmed, measure the angle and degree of eye deviation, whether it is inward or outward, constant or intermittent. The doctor will also take a history to assess risks of vision loss and perform a detailed vision evaluation. If cataracts or tumors are found, they must be treated first.
- After correcting other abnormalities, if the strabismus persists, the doctor will prescribe glasses. If amblyopia is detected, treatment involves patching the normal eye to train the weaker eye.
- If after treating the cause, training the lazy eye, and wearing glasses the strabismus does not improve, surgery may be considered. In children, general anesthesia is required. Risk assessment for safety is done by a pediatrician, including blood tests, red blood cell count, chest X-ray, and COVID-19 screening before surgery. Once all checks are complete, anesthesia and surgery proceed, lasting about 1 hour. The surgery is performed outside the eye. After surgery, the eye is patched for 1 day, then can be opened and used normally the next day. Avoid water exposure for 1-2 weeks. Some redness may occur but is not harmful. Eye drops are used as prescribed for about 2 weeks until inflammation subsides and the redness disappears.
- After surgery, strabismus usually improves or resolves immediately. However, there is a risk of recurrence or need for repeat surgery. Poor eye care, not wearing glasses, or untreated refractive errors can cause strabismus to return. Therefore, as long as vision is used, eye care, behavioral adjustments, and regular eye health checks are necessary to prevent recurrence or other eye abnormalities.
Abnormal eye muscle condition can develop later due to excessive or improper eye use and does not always have to be congenital. Therefore, regular eye health checks for children are important to keep their eyes safe and free from abnormalities. Parents should also watch for suspicious symptoms. If strabismus is noticed, consult a doctor immediately for diagnosis and treatment to avoid serious complications, especially in children under 8 years old who need close eye monitoring. If amblyopia is diagnosed after 8 years old, treatment may be too late, and the child may never regain normal vision. If congenital strabismus is treated after age 4, the child may lose 3D vision for life.
It takes time for a child’s visual development to be complete. If abnormalities occur during growth and the child cannot communicate them, delayed treatment can be more harmful than expected. Therefore, parents must pay attention and carefully observe any abnormal eye symptoms. If strabismus or abnormal eye muscle condition is noticed, even intermittently, do not delay and consult a doctor promptly.
Dr. Natsucha Wangthiramanuy
Pediatric Ophthalmologist
Eye Center, Phyathai 3 Hospital
