Purpose: To describe baseline measures of refraction, accommodation, and heterophoria in Japanese school children enrolled in a randomized clinical trial that examines whether progressive addition lenses slow myopic p...Purpose: To describe baseline measures of refraction, accommodation, and heterophoria in Japanese school children 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 - 6.00D 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 ± 1.22D. The cycloplegic subjective refraction was larger (less myopic) than the noncycloplegic subjective refraction by 0.25 ± 0.22D. The mean distance prescription was larger (undercorrection) than the mean cycloplegic autorefraction by 0.74± 0.37D. The mean accommodative lag for a 4.74D target was 2.05± 0.98D. Nearpoint esophoria was found in 29 (31% ) of the children when their refractive errors were fully corrected with glasses. Conclusions: The measurements reported here in 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.展开更多
Purpose: To determine whether or not myopic children have a larger lag of acco mmodation than emmetropic children under natural seeing conditions. Methods: In 61 myopic children (age, 9.5±1.3 years; spherical equ...Purpose: To determine whether or not myopic children have a larger lag of acco mmodation than emmetropic children under natural seeing conditions. Methods: In 61 myopic children (age, 9.5±1.3 years; spherical equivalent refractive error, -6.50 to-1.00D), accommodative response was objectively measured while they we re binocularly viewing a target at 50.5, 32.5, 20.9, or 16.0 cm (1.98-6.25 D) t hrough fully correcting glasses. In the 33 children who habitually wore spectacl es, the accommodative responses were also measured while they wore their own spe ctacles. As controls, 18 emmetropic children were recruited. Accommodative respo nse gradients and lags were compared between the groups after calibration for re sidual refractive errors and the vertex distance of the glasses. Results: With f ully correcting glasses, the myopic children showed a larger mean lag of accommo dation than the emmetropic children, as well as wide intersubject variation. How ever, when the children wore their habitual, usually undercorrecting, spectacles , accommodative lags markedly decreased, and a significant correlation was found between residual refractive errors after correcting for the spectacles and acco mmodative lags. Myopic children with near-point exophoria tended to show smalle r lags of accommodation. Conclusion: Under binocular viewing conditions, myopic children when viewing the target through fully correcting glasses tend to show l arger lags of accommodation than emmetropic children, but the lags of accommodat ion are usually reduced by their spectacle undercorrection.展开更多
文摘Purpose: To describe baseline measures of refraction, accommodation, and heterophoria in Japanese school children 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 - 6.00D 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 ± 1.22D. The cycloplegic subjective refraction was larger (less myopic) than the noncycloplegic subjective refraction by 0.25 ± 0.22D. The mean distance prescription was larger (undercorrection) than the mean cycloplegic autorefraction by 0.74± 0.37D. The mean accommodative lag for a 4.74D target was 2.05± 0.98D. Nearpoint esophoria was found in 29 (31% ) of the children when their refractive errors were fully corrected with glasses. Conclusions: The measurements reported here in 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.
文摘Purpose: To determine whether or not myopic children have a larger lag of acco mmodation than emmetropic children under natural seeing conditions. Methods: In 61 myopic children (age, 9.5±1.3 years; spherical equivalent refractive error, -6.50 to-1.00D), accommodative response was objectively measured while they we re binocularly viewing a target at 50.5, 32.5, 20.9, or 16.0 cm (1.98-6.25 D) t hrough fully correcting glasses. In the 33 children who habitually wore spectacl es, the accommodative responses were also measured while they wore their own spe ctacles. As controls, 18 emmetropic children were recruited. Accommodative respo nse gradients and lags were compared between the groups after calibration for re sidual refractive errors and the vertex distance of the glasses. Results: With f ully correcting glasses, the myopic children showed a larger mean lag of accommo dation than the emmetropic children, as well as wide intersubject variation. How ever, when the children wore their habitual, usually undercorrecting, spectacles , accommodative lags markedly decreased, and a significant correlation was found between residual refractive errors after correcting for the spectacles and acco mmodative lags. Myopic children with near-point exophoria tended to show smalle r lags of accommodation. Conclusion: Under binocular viewing conditions, myopic children when viewing the target through fully correcting glasses tend to show l arger lags of accommodation than emmetropic children, but the lags of accommodat ion are usually reduced by their spectacle undercorrection.
