Strabismus in Children
Childhood strabismus is a visual defect that consists of the loss of parallelism of the eyes, so that each eye looks in one direction. As a consequence, an abnormal deviation of one or both eyes occurs in one of the gaze positions.
There are different types of strabismus, depending on whether the deviation occurs inwards (receives the name of "esotropia" or "crossed eyes"), outwards (receives the name of "exotropia"), upwards (hypertropia) or downwards ( hypotropia).
When the eyes are not aligned, the aligned eye or the more aligned eye becomes the dominant eye. The visual acuity of that eye is preserved because the eye and its connection to the brain function properly. Conversely, the misaligned or weaker eye doesn't focus as it should, and its connection to the brain doesn't form correctly.
What are the causes of strabismus in children?
Different causes can influence the appearance of a childhood strabismus. The most frequent are:
- An inadequate functioning of the eye muscles by the brain.
- The association with a refractive defect, which, mainly, is usually farsightedness (lack of sharpness or blurred vision of nearby objects).
- Caused by brain problems (cerebral palsy, hydrocephalus, or prematurity).
- Down's syndrome.
- Any injury to the eye that affects vision.
However, squints can also arise at any age when there is a strong stress picture where our central nervous system is overloaded and there is a misalignment of the position of the eyes.
How is it corrected?
Mainly, it should be a pediatric ophthalmologist who assesses the degree of deviation, ocular motility, refraction and fundus in order to choose the best treatment for the child.
If there is a refractive defect to begin with, it is usually treated by optical correction with glasses or contact lenses. Generally, optical correction cures strabismus on its own. If a amblyopia (one eye does not communicate well with the brain), vision in that eye will need to be restored, which is usually achieved by covering the healthy eye with a patch.
Another way to correct strabismus can be by performing a series of muscle exercises that help align the eyes correctly to focus on objects, especially close ones. The objective of these exercises is to get both eyes to see at the same time and to correct the ocular deviation.
If, once the optical defects and amblyopia have been corrected, the ocular deviation persists, surgical operation is necessary. In surgery, the extraocular muscles responsible for eye mobility are acted upon to weaken or strengthen their action, achieving proper eye alignment. The ocular plastic surgery unit is usually responsible for taking care of this type of intervention.
Botulinum toxin injection may be an alternative to surgery in some cases.
When does strabismus contract?
Most children with strabismus are diagnosed when they are between 1 and 4 years old. In rare exceptions, a child may develop strabismus after the age of 6. When this happens, it is important to see a doctor with your child as soon as possible to rule out other diseases.
Can strabismus be prevented?
Strabismus cannot be prevented, but if an early diagnosis is made it can be properly corrected and permanent vision loss can be avoided.
How is strabismus detected?
The best way to detect strabismus are regular eye exams. Early diagnosis and treatment improve a child's chances of aligning their eyes and developing good vision and depth perception.