角膜塑形术前后角膜地形图与角膜曲率计一致性研究

目的比较角膜塑形术前后EyeSys角膜地形图系统与角膜曲率计测量角膜屈光力与散光轴向的差异。方法对进行角膜塑形术治疗的321例患者在术前及术后1d、术后1个月分别进行角膜地形图及角膜曲率计的检查,对两种方法所测得的水平子午线角膜屈光力(HK)、垂直子午线屈光力(VK)、角膜散光及轴向进行比较。结果角膜塑形术前、术后1d、术后1个月,角膜地形图仪测量的HK值分别为(43.25±1.16)D、(42.88±1.18)D、(42.79±1.87)D,较角膜曲率计测量的HK值分别高0.20D、0.39D、0.40D,差异均有显著统计学意义(均为P<0.01)。角膜地形图仪测量的VK值分别为(44.39±1.33)D、(43.96±1.33)D、(43.02±1.64)D,较角膜曲率计测量的VK值高0.13D、0.32D、0.73D,差异均有显著统计学意义(均为P<0.01)。角膜地形图仪测得角膜散光值均较角膜曲率计小,术前、术后1d、术后1个月分别小0.06D、0.10D、0.40D。术后两种方法测量HK、VK、角膜散光及散光轴向之间的差异逐渐增大(P<0.01),并且两种方法的轴向差异朝着逐渐变大的方向分布。但两种方法对顺规及非顺规散光的检出率差异均无统计学意义(均为P>0.05)。结论 EyeSys角膜地形图系统可以更全面及准确地了解角膜塑形术过程中的角膜情况,故临床上应以角膜地形图的结果作为主要依据,角膜曲率计的结果仅可以作为参考。

Consistency study between corneal topography and keratometer during orthokeratology

Objective To evaluate the difference of corneal power and astigmatism axis measured by EyeSys corneal topography and keratometer during orthokeratology.Methods Three hundreds and twenty-one cases underwent orthokeratology performed the examination of corneal topography and keratometer at pre-operation and postoperative 1 day,1 month,the horizontal meridian power magnitude(HK),vertical meridian power magnitude(VK),corneal astigmatism magnitude and its axis measured by two instruments were compared.Results At pre-operation and postoperative 1 day,1 month,HK measured by corneal topography were(43.25±1.16)D,(42.88±1.18)D,(42.79±1.87)D,which were respectively 0.20 D,0.39 D,0.40 D higher than that measured by keratometer,there were significant differences(all P<0.01);VK measured by corneal topography were(44.39±1.33)D,(43.96±1.33)D,(43.02±1.64)D,which were respectively 0.13 D,0.32 D and 0.73 D higher than that measured by keratometer,there were significant differences(all P<0.01).Astigmatisms measured by corneal topography were 0.06 D,0.10 D and 0.40 D lower than measured by keratometer before and after orthokeratology.The difference of HK,VK,astigmatism and its axis measured by two instruments were greater during treatment(P<0.01),and the difference of astigmatism axis had the gradually enlarged tendency.There was no significant difference between two instruments in screening rate of rule astigmatism and non-rule astigmatism(P>0.05).Conclusion EyeSys corneal topography as a useful topographic system,can offer complete and accurate information during orthokeratology,so the result of corneal topography should be considered as the main basis,and only taking keratometer as the reference.