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What is Strabismus?

Strabismus (ocular misalignment) is a condition where one eye looks straight ahead and the other eye turns inwards or outwards.



Why is it important to treat strabismus?

Normal, good vision requires accurate coordination between the two eyes. When the eyes are not aligned the brain receives two different images. The brain cannot register two different images and, therefore, it ignores the image coming from one of the eyes. This problem does not enable the eyes to work together and, therefore, in a condition where there is no binocular vision, one cannot see three dimensions.  In addition, as a result of the strabismus, a phenomenon of amblyopia ("lazy eye") may be caused.

What are the common types of strabismus?

Convergent Strabismus, where the eye turns inward is termed Esotropia ("crossed-eyes").​

There are several types of esotropia:

Congenital Esotropia – estropia that appears before six months of age.

Sometimes there is a family history of this esotropia, and in most cases, a surgical intervention is necessary.


Accommodative Esotropia – this esotropia usually appears between 7 months and 4 years of age, with an average at 2.5 years old. The esotropia can appear suddenly and can also appear and disappear repeatedly. This type of esotropia occurs mainly in children suffering from farsightedness. It is treated by fitting glasses. Sometimes, it should be mentioned, this is not sufficient, and here, as well, a surgical intervention is required. This esotropia, then, is termed partial accommodative esotropia.

There are also esotropias caused by syndromes, for instance Duane's Syndrome and Congenital Fibrosis Syndrome, which are esotropias that are more difficult to treat, and in certain cases, even necessitate surgery.

Divergent Strabismus, where the eye turns outwards is termed Exotropia ("wall-eyes")

This strabismus usually appears after one year of age. The exotropia can be permanent or impermanent, meaning exotropia that only appears from time to time, especially during fatigue or illness. The exotropia is more pronounced when the child focuses on distant targets. When the child is exposed to sunlight he/she may shut one of the eyes.

There are, obviously, additional types of strabismus that are less common, about which I shall not elaborate within the scope of this website.


Accommodative Esotropia

What is the goal of the treatment?

The goal of treating strabismus is restoring binocular vision that will enable depth perception and three dimensional vision.

How is strabismus treated?

  1. Glasses
  2. Surgery
  3. Patch/drops

By fitting glasses, some of the strabismus types can be corrected, as I have explained, but sometimes this will not suffice.     Sometimes surgical intervention is also necessary.

Sometimes patches and even drops are required for treating amblyopia ('lazy eye'- see explanation "amblyopia").