角膜屈光手术后人工晶状体屈光度计算方法的临床研究

Chen Xu, Ji Ying-hong, Jiang Yong-xiang, Luo Yi, Jiang Chun-hui, Lu Yi

Department of Ophthalmology, Eye and ENT Hospital, Fudan University, Shanghai, China.

Zhonghua Yan Ke Za Zhi. 2010 Jun;46(6):518-24.

OBJECTIVE

To evaluate the results of cataract surgery in myopia patients after laser in situ keratomileusis (LASIK) and to compare the predictability of various methods of intraocular lens (IOL) power calculation.

METHOD

Seventeen cases (24 eyes) who had LASIK for myopia were divided into two group by with or without history of corneal power data. Corneal power was obtained by autokeratometry, corneal topography, Pentacam and IOL Master. The IOL power was calculated with the clinical history method, Feiz-Mannis formula, Feiz-Mannis method and other methods. Postoperative final refraction and the deviation of the final spherical equivalent (SEQ) from the refractive target were measured 3 month after the surgery. Two sample t-test, linear correlation and regression analysis, paired t-test and Bland-Altman method of agreement were used to analyze these data.

RESULTS

In the group with history data, the mean corneal power was (43.28 ± 1.21) D and the mean SEQ was (-15.33 ± 4.36) D before the LASIK surgery. In the group without history data, the mean SEQ was (-10.11 ± 3.12) D. Before cataract surgery, the mean corneal power was (36.96 ± 2.07) D and (36.85 ± 1.40) D in these two groups. The mean arithmetic refractive prediction error after cataract surgery was (-0.66 ± 1.27) D and (-0.47 ± 0.82) D in these two groups, respectively. Data calculated by using Hamed-Wang-Koch method, Masket Formula, Koch/Maloney method, Shammar method and Pentacam ERK method were lower than the emmetropic IOL power. Data calculated by using Feiz-Mannis Formula, Latkany Method, Savini method, Armberri Double K method were overestimated. The mean arithmetic errors of clinic history method, Corneal Passby Method and Haigis-L Formula were not significantly different from the predict refraction (P = 0.364, 0.318 and 0.069; t = 0.956, -1.057 and -1.911, respectively). There was strong correlation between the value calculated by using Feiz-Mannis Method or Haigis-L Formula and the true power (r = 0.921, 0.915; P = 0.000 and 0.000, respectively). But none of the values calculated by these method could fully agree with the true value.

CONCLUSIONS

IOL power should be calculated accurately to avoid undercorrection. We recommend the combination of clinical history method, Feiz-Mannis Method, Corneal Passby Method and Haigis-L Formula for the calculation of IOL power.

目的

评估近视患者行准分子原位角膜磨镶术（LASIK）后白内障手术的效果，并比较各种人工晶状体（IOL）屈光度计算方法的可预测性。

方法

17例（24只眼）因近视行LASIK手术的患者，根据有无角膜屈光度数据分为两组。通过自动角膜曲率计、角膜地形图、Pentacam和IOL Master获取角膜屈光度。采用临床病史法、Feiz-Mannis公式、Feiz-Mannis法等方法计算IOL屈光度。术后3个月测量最终屈光度数及最终等效球镜度（SEQ）与屈光目标的偏差。采用两样本t检验、线性相关及回归分析、配对t检验和Bland-Altman一致性分析方法对这些数据进行分析。

结果

有病史数据组，LASIK手术前平均角膜屈光度为（43.28±1.21）D，平均SEQ为（-15.33±4.36）D。无病史数据组，平均SEQ为（-10.11±3.12）D。白内障手术前，两组平均角膜屈光度分别为（36.96±2.07）D和（36.85±1.40）D。白内障手术后两组平均算术屈光预测误差分别为（-0.66±1.27）D和（-0.47±0.82）D。采用Hamed-Wang-Koch法、Masket公式、Koch/Maloney法、Shammar法和Pentacam ERK法计算的数据低于正视眼IOL屈光度。采用Feiz-Mannis公式、Latkany法、Savini法、Armberri双K法计算的数据被高估。临床病史法、角膜旁过法和Haigis-L公式的平均算术误差与预测屈光度数无显著差异（P分别为0.364、0.318和0.069；t分别为0.956、-1.057和-1.911）。采用Feiz-Mannis法或Haigis-L公式计算的值与真实屈光度之间存在强相关性（r分别为0.921、0.915；P均为0.000）。但这些方法计算的任何值均不能完全与真实值一致。