方法：横断面研究。收集2020-05/2021-05来院就诊的白内障患者149例181眼。术前使用iTrace、IOL Master 700和Pentacam HR三种仪器测量陡峭轴角膜曲率(Ks)、平坦轴角膜曲率(Kf)、平均角膜曲率(Km)、角膜散光度数(Cyl)、陡峭轴轴位(Axis)。分析三种仪器测量指标的差异性及一致性。

结果：三组仪器间测量Ks、Kf、Km均有差异(F=4.912、3.514、4.873，均P<0.05)，Cyl与Axis均无差异(F=0.523、0.128，均P>0.05)。Bland-Altman分析提示iTrace与另两种仪器测量的Ks、Kf一致性较差，Cyl和Axis的一致性好，但Axis差值不在临床可接受范围。低度散光组(50眼)、中度散光组(34眼)和高度散光组(18眼)的iTrace与另两种仪器的测量值差值均无差异(P>0.05)。

结论：iTrace与IOL Master 700和Pentacam HR在白内障患者术前测量除散光度一致性好外，其余Ks、Kf均有差异性，Axis差值偏大，超过临床可接受范围，尤其是高度散光组。白内障术前角膜散光的测量应选择多种测量仪器，全方位规划手术方案。

METHODS: Across-sectional study. From May 2020 to May 2021, a total of 149 cataract patients(181 eyes)were collected in our hospital. Presurgery, steep keratometry(Ks), flat keratometry(Kf), mean keratometry(Km), astigmatism magnitude(Cyl), and steep astigmatic axis values measured by the three instruments of the iTrace, IOL Master 700 and the Pentacam HR. The difference and consistency of the measurement indexes of the three instruments were analyzed.

RESULTS: Statistical differences existed in Ks, Kf, Km among the three instruments(F=4.912, 3.514, 4.873, all P<0.05)and there was no difference in Cyl and Axis(F=0.523, 0.128, all P>0.05). Bland-Altman analysis showed the outcomes revealed that the Ks and Kf measured by iTrace and the other two instruments have poor consistency, and the consistency of Cyl and Axis was good. But the difference of Axis is not clinically acceptable. There were no statistically differences between the iTrace and the other two devices among the low astigmatism(50 eyes), moderate astigmatism(34 eyes)and high astigmatism(18 eyes)groups(all P>0.05).

CONCLUSION: In the preoperative measurement of cataract patients except for the good consistency of astigmatism, the iTrace, IOL Master 700 and Pentacam HR showed different Ks and Kf, and the Axis difference exceeded the clinically acceptable range, especially in the highly astigmatism group. The measurement of corneal astigmatism before cataract surgery should be evaluated by multiple measurement methods and make comprehensive planning for the surgical plan.