Hua Yan-jun, Huang Jin-hai, Pan Chao, Wang Qin-mei
Wenzhou Medical College, Wenzhou, China.
Zhonghua Yi Xue Za Zhi. 2012 Sep 4;92(33):2339-44.
To compare the different evaluations of corneal power in post-laser-assisted in situ keratomileusis (LASIK) eyes and assess the accuracy and differences of intraocular lens (IOL) power prediction with corneal powers through different calculation methods.
For this prospective study, 71 eyes of 39 candidates undergoing LASIK and 3 months later returning for reexamination were included. All subjects were divided into 2 groups according to the axial length: Group A (23.46 - 25.97 mm) 44 eyes, Group B (26.00 - 28.52 mm) 27 eyes. The ranges of spherical equivalents were -1.75 - -9.50 D with an average of (-4.82 ± 1.98) D. Subjective refraction and Pentacam Scheimpflug analyzer were performed at pre-operation and subjective refraction, IOLMaster and Galilei II dual Scheimpflug analyzer at over 3 months post-operation. The following values were obtained: SimK by Galilei II dual Scheimpflug analyzer, Kn calculated with Gaussion thick lens formula, Kray with ray tracing method, Kchm calculated with clinical history method and Km by IOLMaster. Repeated measures analysis of variance analyze the differences between SimK, Kn, Kray, Km and Kchm. Repeated measurement analysis of variance was employed to analyze the differences between SimK, Kn, Kray, Km combining intraocular lens power formula and Kchm combining intraocular lens power formula. Pearson's analysis was performed to analyze the correlations between SimK, Kn, Kray, Km and Kchm. Those combining with formulas for IOL power calculations were also analyzed. P < 0.05 indicated statistical significance.
The values of SimK, Kn, Kray, Km and Kchm were (39.02 ± 1.8), (37.8 ± 1.51), (36.8 ± 1.84), (39.18 ± 1.75) and (38.55 ± 1.83) D respectively. The differences between SimK, Kn, Kray, Km and Kchm had statistical significances (P < 0.01). High correlations existed between SimK, Kn, Kray, Km and Kchm (r > 0.9, P < 0.01). In the same IOL formula, Kray had the highest IOL power value, Kn followed, Kchm the third, SimK and Km the smallest. Among the IOL formulas, Haigis-L and Haigis predicted the highest IOL power, HofferQ followed, Holladay the third and SRK/T the smallest.
Kn/Kray combining with Haigis formula may be a new and effective method for predicting the IOL power in post-LASIK eyes.
比较准分子激光原位角膜磨镶术（LASIK）术后眼睛角膜屈光力的不同评估方法，并通过不同计算方法评估人工晶状体（IOL）屈光力预测的准确性及差异。
本前瞻性研究纳入了39例接受LASIK手术且术后3个月复诊的患者的71只眼。所有受试者根据眼轴长度分为2组：A组（23.46 - 25.97 mm）44只眼，B组（26.00 - 28.52 mm）27只眼。等效球镜度范围为-1.75 - -9.50 D，平均为（-4.82 ± 1.98）D。术前进行主观验光和Pentacam眼前节分析系统检查，术后3个月以上进行主观验光、IOLMaster及Galilei II双眼前节分析系统检查。获取以下数值：Galilei II双眼前节分析系统测量的SimK值、用高斯厚透镜公式计算的Kn值、光线追踪法测量的Kray值、临床经验法计算的Kchm值及IOLMaster测量的Km值。采用重复测量方差分析SimK、Kn、Kray、Km和Kchm之间的差异。采用重复测量方差分析SimK、Kn、Kray、Km联合人工晶状体屈光力公式与Kchm联合人工晶状体屈光力公式之间的差异。采用Pearson分析SimK、Kn、Kray、Km和Kchm之间的相关性。对联合人工晶状体屈光力计算公式的情况也进行了分析。P < 0.05表示差异有统计学意义。
SimK、Kn、Kray、Km和Kchm值分别为（39.02 ± 1.8）D、（37.8 ± 1.51）D、（36.8 ± 1.84）D、（39.18 ± 1.75）D和（38.55 ± 1.83）D。SimK、Kn、Kray、Km和Kchm之间的差异有统计学意义（P < 已删除的内容：0.01）。SimK、Kn、Kray、Km和Kchm之间存在高度相关性（r > 0.9，P < 0.01）。在同一人工晶状体公式中，Kray的人工晶状体屈光力值最高，Kn次之，Kchm第三，SimK和Km最小。在人工晶状体公式中，Haigis-L和Haigis预测的人工晶状体屈光力最高，HofferQ次之，Holladay第三，SRK/T最小。
Kn/Kray联合Haigis公式可能是预测LASIK术后眼睛人工晶状体屈光力的一种新的有效方法。
