Long-term Cosmetic Alignment Following Surgery for Esotropia Versus Exotropia in Childhood: A Comparison Using Survival Curves.

PURPOSE: Although long-term results following repair of esotropia and exotropia in childhood have been reported, the two entities have never been directly compared.

METHODS

Records of all children younger than 18 years who underwent horizontal strabismus surgery from 2000 through 2012 were reviewed. Children with structural eye pathology, severe vision loss, neurologic disorders, and incomitant or combined horizontal and vertical deviations were excluded. Failure was defined by a second horizontal surgery or a primary position deviation greater than 20 prism diopters (PD) at any time during follow-up (as long as 10 years). A threshold of 20 PD was chosen because families often consider deviations important enough to warrant a first or second surgery if it is larger but not if it is smaller.

RESULTS

Of 317 children, 235 with esotropia had surgery at a mean age of 42 months and 82 with exotropia had surgery at a mean age of 60 months. Overall, surgery was successful in 78% of those with esotropia and 65% of those with exotropia. A second surgery was performed in 29 (12%) of those with esotropia and 15 (18%) of those with exotropia. The mean deviation at last follow-up, using absolute values, was 9 PD for esotropia and 10 PD for exotropia. Survival curve success was better for esotropia (P = .008).

CONCLUSION

By survival curve analysis, success was more likely among children with esotropia. Many "failures" slipped beyond the 20 PD threshold only transiently and had deviations that were not noticeable to family or friends. Overall, children did reasonably well long-term following surgery for both esotropia and exotropia. Only 14% of the entire group required a second surgery during an average of 41 months of follow-up.