Refractive error changes in children with intermittent exotropia under overminus lens therapy.

Purpose: Intermittent exotropia may be decreased by stimulation of accommodative convergence. Once excessive accommodation has been related to myopia, our objective was to evaluate refractive errors changes in children under overcorrecting minus lens therapy.

Methods: A retrospective chart review of 21 children with intermittent exotropia was performed. All patients were treated with occlusion, and a 13-patient subset of them received overminus lens therapy (group A). Eight children received spectacles as necessary (group B). Initial age, age interval, initial spherical equivalent (SE), and magnitude of overcorrection were considered as co-variables of the mean variation in refractive error (SE of each eye) between groups, through a multivariate analysis.

Results: Overcorrection used in group A ranged from 0.5 D to 3.5 D (2.46 +/- 0.87 D). Although initial SE of each eye was significant different between group A and B (OD - p=0.02; OS - p=0.01), initial age (p=0.69), age interval (p=0.90), and mean variation in refractive errors (p=0.36) did not differ between groups. Multivariate analysis with linear regression showed no significantly difference regarding all co-variables enrolled.

Conclusions: Treatment of intermittent exotropia with overcorrecting minus lens did not induce refractive errors changes, even considering age, treatment period, initial spherical equivalent and overcorrection magnitude used.