不同力度屏蔽蓝光对正常成年人眼视功能的影响

目的：探索不同程度屏蔽420～460 nm波段蓝光镜片对人眼视功能的防护作用。方法：自身对照研究。2016 年8 月至2017 年3 月选择来自同济大学的健康大学生志愿者20 例，先后在未戴镜，配戴屏蔽20%、30%、40%、60%防蓝光护目镜下，完成24 个色区辨识评分和75 min阅读任务。检测调节幅度、晶状体调节力等指标，并做视疲劳问卷评分。采用配对秩和检验对各组数值进行分析。结果：配戴屏蔽30%、40%和60%防蓝光护目镜和未戴镜比较时，多个色区得分均低于未戴镜（P < 0.05）；而屏蔽20%与未戴镜比较，差异均无统计学意义。完成阅读任务后，在视疲劳调查问卷总得分上，屏蔽20%、30%、40%、60%蓝光得分低于未戴镜（均P < 0.05）。在用眼前后单眼调节幅度差值上、正相对调节差值上，屏蔽20%、30%、40%、60%蓝光变化幅度小于与未戴镜（均P < 0.05）；在用眼前后负相对调节差值上，40%、60%蓝光变化幅度小于未戴镜（P < 0.05）；屏蔽20%、30%蓝光和未戴镜比较差异无统计学意义。在用眼前后晶状体调节力差值上，屏蔽20%、30%、40%、60%蓝光和未戴镜相比差异无统计学意义。结论：屏蔽蓝光的波段以440 nm为中心，带宽20 nm，屏蔽力度20%以上时，可以改善人眼调节力、视疲劳主观症状。但屏蔽该段蓝光力度达30%以上时，会造成色差症状。

Effect of Different Intensities of Blue Light Shielding on Visual Function of Normal Adults

Objective: To investigate the influence of different intensities of blue light shielding on the visual function of healthy adults. Methods: This self-controlled study enrolled 20 healthy adults who were students volunteers of Tongji University from August 2016 to March 2017. The subjects completed a 75-min reading task illuminated by blue light (440 nm) at shielding intensities of 0%, 20%, 30%, 40%, and 60%.Twenty-four color partial scoreswere calculated to detect variations in color discrimination. After completing the reading task, visual fatigue, accommodation response, and lens accommodation were assessed and compared amongthe five intensities of blue light shielding. The results were analyzed by signed-ranked test. Results: The scores of many colorswere significantly lower at blue light intensities of 30%, 40%, and60% compared to 0% intensity shielding (P < 0.05). The differences in color scores between 0% and 20% intensity shielding were not statisticallysignificant. After completing the reading task, the visual fatigue scores were lower with 20%, 30%, 40%, and 60% intensity shielding compared to 0% intensity shielding(all P < 0.05). The difference between before and after reading task in accommodation amplitude and positive relative accommodation were significantly lower at 20%, 30%, 40%, and 60% intensity shielding compared to 0% shielding (P < 0.05). Difference between before and after reading task in native relative accommodation were significantly lower at 40% and 60% intensity shielding compared to 0% shielding(P < 0.05). The differences betweenthe before and after reading task values of the 20% and 30% shielding were not significantly different from the 0% shielding. Lastly,differences between before and after reading task in lens accommodation at 20%, 30%, 40%, and 60% intensity shielding were not significantly different from 0% shielding. Conclusions: With blue light (centered at 440 nm) shielding of 20% to 60% intensity20 band wavelength, the accommodation and visual fatigue of healthy adults improved.When the shielding intensity was 30% to 60%, the color perception was worse.