正视眼和近视眼在明暗环境中不同对比度的视力比较

目的正视眼和近视眼人群在明暗环境中不同对比度时的视力的对比研究。方法134例受试者,按屈光不正度数分成正视组、低度近视组、中度近视组和高度近视组。先主觉验光,再用卡洞法找出优势眼,屈光矫正后应用多功能视力测量仪检测优势眼在明和暗环境中不同对比度视力。结果高度近视组在明和暗环境中不同对比度时视力均较其它3组差,与正视组比较有显著性差异(P<0.05)。随着近视屈光度的增加,在明和暗环境中不同对比度时视力呈现下降趋势。在相同对比度下,明环境中的视力好于暗环境中的视力。在相同环境下,随着对比度的下降,视力随之下降。结论框架眼镜矫正时高度近视眼视觉质量明显差于正视眼及低中度近视眼。其视力受环境照明及对比度差异的影响。

Comparison of visual acuity between emmetropes and myopes in different contrast level in bright and dark background

Objective To explore the difference of visual acuity between emmetropes and myopes in difference contrast level in bright and dark background.Methods One hundred and thirty-four volunteers were enrolled and tested.They were divided into four groups according to power of refraction(emmetropes,low myopes,moderate myopes and high myopes).After conducting subjective refraction and testing dominant eyes by using the simplified hole-in-the hand method,visual acuity of dominant eyes was measured in bright and dark background in different contrast level with multi-functional visual acuity tester.Results Visual acuity of high myopes in difference contrast level in bright and dark background were worst among four groups,and the difference in high myopes and emmetropes was statistically significant (P<0.05).With refractive power increasing,visual acuity in different contrast level in bright and dark background gradually decreased.At the same contrast level,visual acuity in bright background was better than that in dark background.At the same room illumination,with contrast level decreasing,visual acuity was reduced.Conclusion Visual quality of high myopes wearing spectacle was worst among emmetropes,low myopes,medium myopes.Visual acuity was influenced by environment illumination and contrast level.