Surgical correction of childhood intermittent exotropia and the risk of developing mental illness

Purpose: To assess whether successful surgical intervention for intermittent exotropia, or the timing of intervention, has any effect on the development of mental illness.

Design: Retrospective, observational case series.

Methods: All patients (<19 years of age) diagnosed with intermittent exotropia in Olmsted County, Minnesota, from January 1, 1975, through December 31, 1994, were reviewed retrospectively. Potential cases were identified using the resources of the Rochester Epidemiology Project, a medical records database designed to capture data on any patient-physician encounter in Olmsted County, Minnesota. The main outcome measures were the occurrence and severity of mental illness among those who underwent strabismus surgery compared with those who did not.

Results: Ninety-six (52%) of the 184 children identified were diagnosed with a mental illness at a mean age of 23.3 years (range, 6 to 41 years). Thirty-five (36%) of the 96 children in whom mental illness developed underwent strabismus surgery. Success at surgery (<10 prism diopters) was not associated with a decreased occurrence of mental illness (P = .30). Of the 88 patients in whom mental illness did not develop, strabismus surgery was not more commonly performed (P = .54), nor was it performed at a younger age (P = 1.0), when compared with the 96 patients in whom mental illness developed later.

Conclusions: Strabismus surgery for children with intermittent exotropia, regardless of success or age at surgery, did not alter the development of mental illness by early adulthood.