Wednesday, 19 February 2014 12:42

Strabismus and Amblyopia

What is strabismus?

Strabismus is a very common childhood disorder that affects 4% of the general population and is an eye condition in which the visual axes of the eyes are not aligned. In this case, one eye looks straight while the other diverts towards inside or outside. Based on the direction of the eye, there is esotropia when the eye is turned towards the inside, exotropia when it is turned towards the outside, anotropia, when it looks up etc. Strabismus can appear in the first months of the infant's life, especially esotropia, or after 18-24 months, when the child starts focusing on close objects.


When a child presents strabismus, and this is more easily observed by his mother, then he will need to be examined to diagnose if it is true strabismus or pseudostrabismus, especially in the ages of 3 and 4, when ocular muscles and the child's vision are not yet stabilized. A very common cause of pseudostrabismus is epicanthus (eye fold) and a wide nose. Pseudostrabismus corrects itself and needs no treatment, while real strabismus must be corrected as soon as possible, because apart from a cosmetic problem (parents consider it a major problem), there is also the danger of amblyopia. The eye that squints in a child may gradually become “lazy”, which means that it stops seeing clearly even with the help of glasses. This is practically irreversible after the first decade of a child's life and the “lazy” eye will stay “lazy” for life. Immediate diagnosis and proper treatment help in order to avert such a possibility.

How is strabismus treated?

When a child shows signs of strabismus, he needs to be examined by an ophthalmologist to diagnose the type and cause of strabismus. Vision and refraction should also be checked using dilating drops to see what the precise dilating strength of the glasses is. At the same time, the fundus is checked for possible abnormalities.

There are cases of strabismus corrected only with glasses, which the child must wear constantly and must be checked every 6-12 months. In esotropia, hyperopia is also found, which increases until the age of 6, stabilizes by the age of 8 and gradually decreases by the age of 14. With the gradual decrease in glasses strength, the degree of strabismus is also decreased. Strabismus that cannot be corrected with glasses will need surgery. With surgery we can strengthen or weaken the muscles in order to align the eyes. In case strabismus is high or complex, e.g. horizontal and vertical, a second surgery might be needed.

It is very important to point out the importance of eye exams before the school age, even if parents cannot observe any problems in their child.

What is amblyopia?

Amblyopia, or “lazy” eye, is not only caused by strabismus. Big differences in the refractive ability of the two eyes, e.g. one-sided high congenital myopia (anisometropic amblyopia), conditions that don't allow light to reach the posterior segment of the eye, e.g. ptosis, congenital cataract (amblyopia ex anopsia), high ametropias, usually hyperopia (ametropic amblyopia), from non-corrected astigmatism (meridional amblyopia) and other disorders, e.g. congenital nystagmus, are all possible to cause amblyopia to a child. Diagnosis and etiological treatment is the basis of proper medical care of this not at all rare disorder, since about 7% of people have some degree of amblyopia acquired during their childhood.

How is amblyopia treated?

The first and most serious issue is proper diagnosis and prevention of amblyopia and this can happen only with a full ophthalmological examination. Treating the basic cause, e.g. strabismus, cataract removal, or prescribing the proper glasses is not enough to correct amblyopia. Besides all that, the good eye needs to be covered so the child will need to use the amblyopic eye to see and thus acquire good vision.

The younger the child is when amblyopia is diagnosed, the better his vision will be after treatment. We need to point out how necessary it is to do an eye exam before school age, because if the diagnosis is made at that age, the child can have perfect vision, while if it is diagnosed at the age of 7 or 8, amblyopia will be permanent for the rest of the child's life except for exceptional cases.

A very important role in the success of this technique is the positive opinion of the parents and their insistence on the treatment, because no child wants to have his eye bandaged. It is better to be pressured early by the parents than have a lazy eye for the rest of his life that might be an obstacle in his personal career, for example, he will not be able to acquire a driver's license or be accepted in a military academy.

Covering the eye is needed for a few hours every day and for as long as it is necessary, months or even years, since it depends on the degree of amblyopia and the regular application of the cover. In small children, improvement is rapid, but the child will have to be monitored closely until the age of 8 to avoid any possible relapse.

 Remember: Your ophthalmologist is the best source for responsible answers on issues related to your eyes and their health. Under no circumstances is information taken from our website intended to replace him. Seek your doctor for complete information.

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