Lenstar与IOLMaster测量散瞳后儿童眼球生物结构参数的比较

Comparison of ocular segment measurements obtained with Lenstar and IOLMaster in dilated children

目的对儿童散瞳后应用Lenstar和IOLMaster测量眼球生物结构参数，并对2种仪器测量结果进行再现性和一致性评价。方法前瞻性研究。75例（75眼）应用1％盐酸环喷托酯滴眼液快速散瞳．2位操作者分别应用Lenstar和IOLMaster测量其眼轴长度（AL）、最小角膜屈光力径线上角膜曲率（Kf）、最大角膜屈光力径线上角膜曲率（Ks）、平均角膜曲率（Km）、角膜水平直径（WTw）、前房深度（ACD）。Lenstar的再现性通过组内标准差（Sw）、重测系数（TRT）、组内变异系数（CV）和组内相关系数（ICC）进行评估，采用配对t检验评价2种仪器差异性，Bland—Altman法分析2种仪器的一致性。结果Lenstar测得的AL、Kf、Ks、Km和ACD具有较好的再现性，其TRT分别为0．03mm、0．33D、0．22D、0．03D和0．23mm，所有ICC均〉0．99。Lenstar和IOLMaster测量ACD、Wrrw、Ks和Km分别为（3．77±0．20）mm和（3．66±0．20）mm（f=16．194，P〈0．01），（12．11±0．43）mm和（12.41±0．53）mm（t=-5．973，P〈0．01），（43．62±1．49）D和（43．66±1．49）D（t=-2．277，P〈0．05），（43．08±1．36）D和（43．12±1．35）D（t=-2．673，P〈0．01），差异均有统计学意义。2种仪器测量ACD、AL、Kf、Ks、Km的95％一致性区间（LoA）较小，其上0下限最大绝对值分别为0．23mm、0．07mm、0．29D、0．35D和0．29D，一致性较好，而WTW的95％IJOA较大（-1．17-0．57mm），一致性较差。结论Lenstar在不同操作者中再现性良好；Lenstar与IOLMaster测量散瞳后儿童的WTW有差别，一致性较差，但是Lenstar更有优势；测量ACD、AL、Kf、Ks以及Km一致性较好．可以相互参考使用。

Objective To investigate the reproducibility and agreement between Lenstar and IOLMaster when measuring axial length （AL）, anterior chamber depth （ACD）, keratometry for the flattest meridian （Kf）, keratometry for the steepest meridian （Ks）, mean keratometry （Kin） and corneal diameter （WTW） of children after dilation. Methods In this prospective clinical study, 75 eligible children were recruited. One eye of each subject was randomly selected and all subjects were dilated with 1% cyclopentolate. All subjects were examined by two examiners for all parameters （AL, Kf, Ks, Kin, WTW, ACD）. Within-subject standard deviation （Sw）, test-retest repeatability （TRT）, the within-subject coefficient of variation （CV） and the interclass correlation coefficient （ICC） were used to analyze reproducibility. The differences between these ocular parameters were analyzed using a paired t-test. Bland-Airman was used to assess the agreement of the instruments. Results The reproducibility results of AL, Kf, Ks, Km and ACD measured by the two examiners using Lenstar were good. The TRT values were 0.03 ram, 0.33 D, 0.22 D, 0.03 D and 0.23 ram, respectively. All the ICC values were over 0.99. The mean ACD, WTW, Ks and Km obtained by Lenstar and IOLMaster were 3.77±0.20 mm and 3.66±0.20 mm （t=16.194, P〈0.01）, 12.11±0.43 mmand 12.41±0.53 mm （t=-5.973, P〈0.01）, 43.62±1.49 D and 43.66±1.49 D （t=-2.277, P〈0.05）, and 43.08±1.36 D and 43.12±1.35 D （t=-2.673, P〈0.01）, respectively. All these values showed significant differences between the two methods. Bland-Ahman analysis showed that the two instruments had comparable results for ACD, AL, Kf, Ks, and Km. The maximum absolute values of the 95% limits of agreement （LoA） were 0.23 mm, 0.07 mm, 0.29 D, 0.35 D and 0.29 D. But the 95% LoA of WTW was large （-1.17-0.57 mm）, indicating the agreement of WTW between these two instruments was poor. Conclusion The reproducibility is good for Lenstar. The WTW difference between Lenstar and IOLMaster is statistically significant, and the consistency is poor, but Lenstar is much better. Otherwise, the consistency of ACD, AL, Kf, Ks and Km between Lenstar and IOLMaster is good and could be regarded as clinically interchangeable.