OPD-ScanⅢ及IOL-Master 700测量白内障术前角膜曲率和水平角膜直径的比较

Comparison of OPD-Scan III and IOL-Master 700 in measuring corneal curvature and horizontal corneal diameter before cataract surgery

目的比较OPD-ScanⅢ与IOL-Master 700在角膜曲率(平坦曲率K1与陡峭曲率K2)及水平角膜直径(WTW)测量上的差异性及一致性。方法选取2021年10月至2022年9月在航天中心医院眼科行白内障手术的患者268例328眼(右眼164例,左眼164例)。采用OPD-ScanⅢ及IOL-Master 700仪器分别检测患者左右眼的K1、K2以及WTW值并进行分析比较。采用配对t检验进行参数比较;Pearson相关分析检测参数间的相关性;Bland-Altman以及组内相关系数(ICC)分析确定两种仪器相关参数测量的一致性。结果在左右眼参数的测量中,OPD-ScanⅢ测得的K1及K2值均大于IOL-Master 700,WTW值均低于IOL-Master 700的测量值,差异均有统计学意义(均为P<0.001)。OPD-ScanⅢ在左右眼中测得的K1、K2及WTW值与IOL-Master 700所测得的对应值均呈正相关,差异均有统计学意义(均为P<0.001)。两种仪器K1、K2及WTW值在95%一致性界限外的比例均在5%以内,但95%界限内差值绝对值均接近或超过了1.0 D,存在较大的临床偏差。ICC分析证实两种仪器左右眼测量K1及K2值一致性均极好(ICC>0.90)。两种仪器测得的WTW差值与K2值均显著相关(均为P<0.05)。WTW正偏差范围外有5例(83.33%)样本IOL-Master 700测得的K 2在47.03以上。结论OPD-ScanⅢ及IOL-Master 700在测量K1、K2及WTW上存在偏差,临床应用中不可互相替代。IOL-Master 700测得的WTW值大于OPD-ScanⅢ,当其测量的K2≥47.03时,所获得的WTW值参考价值可能有限。

Objective To compare the difference and consistency between OPD-ScanⅢand IOL-Master 700 in the measurement of corneal curvature(flat keratometry,K1 and steep keratometry,K2)and horizontal corneal diameter(white-to-white(WTW)distance).Methods Totally 268 patients with 328 eyes(164 right eyes and 164 left eyes)who underwent cataract surgery at the Department of Ophthalmology of the Aerospace Centre Hospital from October 2021 to September 2022 were selected for this study.The K1,K2,and WTW values of the sampled right or left eyes were measured and analyzed using OPD-ScanⅢand IOL-Master 700,respectively.Parameter comparisons were performed through paired t-tests;correlations between parameters were detected through the Pearson correlation analysis;and the Bland-Altman method and intragroup correlation coefficient(ICC)analysis were employed to determine the consistency of parameter measurements between the two instruments.Results The K1 and K2 values measured by OPD-ScanⅢwere greater than those measured by IOL-Master 700,while the WTW values were lower than those measured by IOL-Master 700,but the differences were statistically significant(all P<0.001).K1,K2,and WTW values measured by OPD-ScanⅢwere positively correlated with the corresponding values measured by IOL-Master 700,and the differences were statistically significant(all P<0.001).The proportions of K1,K2,and WTW values outside the 95%limits of agreement for both instruments were within 5%,but the absolute value of the difference in values within the 95%limits of agreement was close to or more than(1.0)D,indicating a sizeable clinical deviation.ICC analysis confirmed a good consistency between K1 and K2 values of the left and right eyes measured by the two instruments(ICC>0.90).The difference in WTW values measured by the two instruments was significantly correlated with K2 values(both P<0.05).There were 5 samples(83.33%)outside the positive deviation range of WTW values,of which K2 measured by IOL-Master 700 was above 47.03.Conclusion The OPD-Scan III and IOL-Master 700 have been found to have measurement biases when assessing K1,K2 and WTW.In clinical practice,the two instruments cannot be interchanged as an alternative to each other.The WTW values measured by IOL-Master 700 are greater than those obtained by OPD-ScanⅢ;when K2≥47.03,the WTW values may not be reliably referrable.