When does infantile esotropia present?  What are its clinical features?

As the name implies, this condition occurs during infancy.  It may present at birth but most cases present within the first six months of life.

Characteristically, this type of deviation shows a large angle of deviation, so large that either eye may appear unable to move sideways and may even use the head to look at objects in the peripheral field of vision.  The child usually shows a strong preference of fixation with one eye indicating the presence of amblyopia.  This occurs in about half of cases.  When amblyopia sets in, the child has poor prognosis for high-grade stereopsis.

How common is infantile or congenital esotropia?  Does it resolve on its own?

A small transient exodeviation is common children at birth but esodeviation is rare in newborns.  Any persistent esotropia beyond 2 months of age usually will not resolve spontaneously.

What is the cause of this condition?

The cause is probably multifactorial.

Does it run in families?

There is no consistent pattern of inheritance for this condition.  Although there is no family history in some cases, there is a tendency for it to occur in families.

Are there other associated problems?

Other abnormalities of muscle functions can occur with infantile esotropia. These include dissociated vertical deviations, inferior oblique overactions, and nystagmus.  The first two tend to occur much later than the initial eye deviation.  This is one reason why some children had to undergo a second surgery.

Infantile esotropia is not uncommon in children with cerebral palsy and Down’s syndrome.

What is the best treatment for this condition?  When is the optimum time to intervene?

The deviation is best treated with surgery.  The standard procedure is to do this between 6 months and 2 years of age to in order to achieve peripheral fusion (1).  However, some authors found that doing surgical intervention earlier than 6 months of age may result to good alignment and high-grade stereopsis (2).  Early surgery is indicated when the amount of deviation is very large (40 prism diopters or larger), and when the deviation is found to be becoming constant or increasing in amount documented in two consecutive visits several weeks apart.  Of course, the child has to be healthy enough to undergo the surgery under general anesthesia.  Spontaneous resolution is a possibility in small deviations; however, it is highly unlikely to happen in large deviations.

Can this be cured with one surgery?

A single procedure may align the eyes if the amount of deviation is not very large.  More than 2 muscles may be involved in very large deviations.  Half of the cases need multiple surgeries to achieve perfect alignment.

References:

1. Ing MR.  Early surgical alignment for congenital esotropia.  Ophthalmology. 1983; 90: 132-135.
2. Wright KW et al.  High-grade stereoacuity after early surgery for congenital esotropia.  Archive Ophthalmol.  1994; 112: 913-919.