近视患者准分子激光原位角膜磨镶术后动、静态对比敏感度的变化

Static and Dynamic Contrast Sensitivity of Myopic Eyes before and after Laser in situ Keratomileusis

目的观察近视患者准分子激光原位角膜磨镶术(laserinsitukeratomileusis,LASIK)后动、静态对比敏感度的变化。方法对2002年2月～2002年6月在我院接受LASIK手术的37例近视和近视散光患者(共73眼)进行了术前,术后1、3、6个月的视力,裂隙灯,散瞳眼底,散瞳检影验光,角膜地形图,动、静态对比敏感度0.7、1.4、2.7、5.5、11、22频率段的观察。结果LASIK术后1个月动态对比敏感度和静态对比敏感度较术前普遍下降,静态对比敏感度在2.7、5.5、11(P<0.01)和22cpd(P<0.05)有显著性下降,11cpd最敏感;而动态对比敏感度则在5.5(P<0.01)、11cps(P<0.05)下降有统计学意义,11cps最敏感;≥6.25D近视组和≥2DC散光组下降更明显。术后3个月,动、静态对比敏感度各频率段逐渐恢复并超过术前水平,术后6个月继续提高。静态对比敏感度所有频率段均超过术前水平(P<0.01),而动态对比敏感度在2.7、5.5、11cps(P<0.01)超过术前水平,≤6.0D近视组和<2.0DC散光组提高更明显。频率越高,提高率越大,以22cpd和22cps最明显。而≥2DC的散光组,动态对比敏感度在术后6个月无显著提高,且1.4cps段还低于术前水平(P<0.05)。结论LASIK术后病例确实有暂时的对比敏感度下降,但是在术后3个月可恢复并超过术前水平,术后6个月有进一步提高。

To evaluate the static and dynamic contrast sensitivity changes in myopic patients before and after laser in situ keratomileusis (LASIK).Methods Seventy-three eyes in37patients with myopia(with or without astigmatism)who received LASIK were tested for static and dynamic contrast sensitivities using the METRO VISION MON ELEC I system at0.7,1.4,2.7,5.5,11,and22cpd and cps prior to LASIK,and at one-,three-,and six-month intervals after LASIK.Results All eyes gained naked visual acuity of more than0.5after LASIK.The contrast sensitivity was depressed at all frequencies1month after LASIK,as compared to one week prior to LASIK.The depression at2.7,5.5,11(P<0.01)and22cpd(P<0.05)was statistically significant for static contrast sensitivity,and also at5.5(P<0.01)and11cps(P<0.05)for dynamic contrast sensitivity.Myopic eyes between6.25D and14.0D,and astigmatic eyes2DC and more,suffered more static and dynamic contrast sensitivity depression than the myopic eyes between1.25D and6.00D and astigmatic eyes less than2DC.Contrast sensitivities were improved and exceeded preoperative levels3months after LASIK,and improved even more6months after LASIK.All sequences were statistically significant for static contrast sensitivity(P<0.01),while only2.7,5.5,and11cps were statistically significant for dynamic contrast sensitivity(P<0.01).The astigmatic eyes2DC and more showed less improvement,even below the preoperative level at1.4cps of dynamic contrast sensitivity.Conclusions While temporary depression of contrast sensitivity for myopic eyes after LASIK was seen,contrast sensitivity soon returned to exceed preoperative levels at3months after LASIK,while improving even more6months after LASIK.