Myopia control trial with progressive addition lenses in Japanese schoolchildren: baseline measures of refraction, accommodation, and heterophoria

Abstract

Purpose: To describe baseline measures of refraction, accommodation, and heterophoria in Japanese schoolchildren enrolled in a randomized clinical trial that examines whether progressive addition lenses slow myopic progression compared with single-focus lenses.

Methods: Ninety-five children with myopia between -1.25 and -6.00 D spherical equivalent were recruited. Their ages ranged from 6 to 12 years; 46% were girls. The main outcome measure for the trial was progression of myopia determined by cycloplegic (0.5% tropicamide) autorefraction. Accommodative lags and heterophoria were also evaluated.

Results: Because data were similar in both eyes, they are reported for the right eye only. The mean (+/-SD) cycloplegic autorefraction (spherical equivalent) was -3.22 +/- 1.22 D. The cycloplegic subjective refraction was larger (less myopic) than the noncycloplegic subjective refraction by 0.25 +/- 0.22 D. The mean distance prescription was larger (undercorrection) than the mean cycloplegic autorefraction by 0.74 +/- 0.37 D. The mean accommodative lag for a 4.74 D target was 2.05 +/- 0.98 D. Near-point esophoria was found in 29 (31%) of the children when their refractive errors were fully corrected with glasses.

Conclusions: The measurements reported herein will serve as a basis for assessing changes that occur over a 3-year follow-up period. Compared with the baseline measurements in the Correction of Myopia Evaluation Trial, clear differences were observed in the mean cycloplegic autorefraction and distance prescriptions. The accommodation and heterophoria data showed characteristics similar to those recently reported in myopic children abroad.