It is an inward deviation of one or both eyes presenting during the first six months of life in an otherwise neurologically normal child. It is sometimes called congenital esotropia, but the deviation is rarely present at birth. Although many theories exist, the true cause of infantile esotropia remains unknown.
The eye deviation is known to be large and constant and affected children sometimes cross fixate to cope with it. They usually have small amounts of hyperopia and prescribing glasses does not alter the deviation.
Affected children should be seen early by a pediatric ophthalmologist so that a comprehensive eye exam can be done. Glasses for hyperopia may be given but surgery should be done during infancy. Doing surgery between 1-2 years of age was found to be associated with better motor and sensory outcomes. Doing the surgery after age 3 and those with very large deviations are associated with the need for a second surgery.
Bilateral medial rectus recession is preferred over unilateral recess-resect due to better outcomes. However, despite a successful early surgery, these children could still develop other eye deviations, such as inferior oblique overaction or dissociated vertical deviation up to 2 years after surgery.
Botox injection to the eye muscles is an alternative to surgery, and may even be used as an adjunct to it for very large deviations, but it is not considered superior to it.