Overminus Lens Therapy in the Management of Children with Intermittent Exotropia

Purpose: To evaluate the results of overminus lens therapy in the management of children with intermittent exotropia or X(T). Methods: In this retrospective study, 163 consecutive patients with X(T) who were treated with overminus spectacles with at least 12 months of follow-up were included in the study. The outcome measures were the level of X(T) control evaluated using the Jampolsky's qualitative assessment method and refractive error changes under overminus lens treatment. Results: The mean angle of deviation at the initial visit was 24.7 +/- 15.1 prism diopters (PD) that improved to 10.6 +/- 4.2 PD with overminus glasses with a median follow-up of 38 months (P = 0.02). One hundred and nine patients (66.8%) achieved good controlled X(T) or orthotropia by overminus lens therapy after 1 year. Three patients progressed to esotropia, which disappeared after discontinuing overminus lens therapy. Overminus lens therapy did not have a statistically significant effect on the mean spherical equivalent of cycloplegic refraction in each eye (right eye: P = 0.13; left eye: P = 0.15). Conclusions: Overminus lens therapy can be effective for improving the control of X(T) in young children. It can defer the requirement for surgery or decrease the rate of surgical intervention.