The maximal tolerable reduction in hyperopic correction in patients with refractive accommodative esotropia: a 6-month follow-up study

Abstract

Purpose: To investigate the optimal amount of safe under-correction in patients with refractive accommodative esotropia.

Design: Prospective noncomparative interventional case series.

Methods: Patients with refractive accommodative esotropia wore trial glasses based on cycloplegic refraction, then -0.25 diopters (D) of minus sphere lenses were placed on both lenses of the trial glasses and the deviation was measured. Minus spheres of -0.25 D were continuously added until the angle of deviation increased; the minus spheres added just before the deviation increase were defined as the maximal tolerable amount of under-correction. A total of 38 patients were prescribed under-corrected spectacles up to -1.5 D and followed for 6 months.

Results: Thirty-one patients underwent the maximal tolerable amount of under-correction and 7 underwent -1.5 D of under-correction. A mean -0.89 D of under-correction was performed. We observed no deterioration in visual acuity, stereoacuity, or fusional ability during the follow-up period in any of the patients. Small increase in the angle of deviation of 2 prism diopters was noted in 2 patients. The mean spherical equivalent refractive error of both eyes (P = .012) and age of onset (P = .006) showed strong positive correlations with the maximal tolerable amount of under-correction.

Conclusions: A reduction in hyperopic correction by the maximal tolerable amount of under-correction was performed without notable short-term side effects. The spherical equivalent refractive error and age of onset appear to be useful clinical indices in determining the appropriate amount of under-correction.

Trial registration: ClinicalTrials.gov NCT01179711.