The disparity in accommodative amplitude under different monochromatic lights and the correlation with refractive state

Objective To measure the binocular accommodative amplitude under different monochromatic lights; to evaluate the differences in accommodative amplitude under different monochromatic lights and the correlation between refractive state and accommodative amplitude.Methods This was a cross-sectional study.Ninety-one subjects (182 eyes),aged 15～30 years (average 22.9±4.2 years) were enrolled in the study.All subjects underwent refractive examinations measured with MPMVA,amplitude of accommodation measured with a minus lens-stimulated test under white light (440 nm,560 nm,610 nm combined light),red light (610 nm) and green light (560 nm).A one-way ANOVA and Pearson correlation were used for statistical analysis.Results ①There were significant differences in the amplitude of accommodation under different lights (F=21.49,P＜0.01):the largest amplitude was under white light (13.04±2.75 D),green light (12.4±2.61 D) was second,and red light (11.26±2.53 D) was the lowest.②The amplitude of accommodation under the 3 hights was significantly different (F=21.476,14.356,16.540,P＜0.01) among emmetropes,low and moderate myopes and high myopes.The smallest amplitude was for emmetropes and the amplitude was for high myopes.The amplitudes of accommodation were not significantly different for emmetropes under different lights (F=1.93,P＞0.05) while the other two groups showed significant differences (F=15.684,11.821,P＜0.01).③There was a positive correlation between the amplitude of accommodation and refraction (r=0.385,0.312,0.328,P＜0.01).④For each individual,the accommodative amplitude was higher with a higher degree of myopia,under red hight,the differences were not significant (t=-1.803,P＜0.05),under white and green lights,the differences were significant (t=-2.344,2.474,P＜0.05).Conclusion The amplitude of accommodation differs when induced by different lights.It is higher with green light than red light,and there was a significant difference in myopes.The amplitude of accommodation is correlated with refractive error; the higher the degree of myopia,the larger the amplitude of accommodation. Key words: Chromatic; Light; Accommodation amplitude; Myopia; Diopter