Wang Zi-Yang, Song Yan-Zheng, Yang Wen-Li, Liu Qian, Li Yi-Feng, Cui Rui, Shen Lin, Zhai Chang-Bin
Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing 100730, China.
Int J Ophthalmol. 2023 Jul 18;16(7):1117-1122. doi: 10.18240/ijo.2023.07.17. eCollection 2023.
To analyze the differences, agreements, and correlation among total corneal power parameters generated by different instruments after myopic keratorefractive surgery.
The prospective cross-sectional study included patients who underwent myopic keratorefractive surgery and received measurements of corneal power 3mo after surgery. Automated keratometer was used for the measurement of simulated keratometry (SimK), swept-source optical coherence tomography (SS-OCT) based biometer for total keratometry (TK), anterior segment-OCT for real keratometry (RK), and Scheimpflug keratometer for the true net power (TNP), the total corneal refractive power (TCRP) and equivalent K-readings (EKR). The differences among these parameters were analyzed, and the agreements and correlation between SimK and other total corneal power parameters were investigated.
A total of 70 eyes of 70 patients after myopic keratorefractive surgery were included. The evaluated corneal power parameters were as follows: SimK 38.32±1.93 D, TK 37.54±2.12 D, RK 36.64±2.09 D, TNP 36.56±1.97 D, TCRP 36.70±2.01 D, and EKR 37.55±2.00 D. Pairwise comparison showed that there were significant differences (<0.001) among all parameters except for between TK and EKR, RK and TNP, RK and TCRP (=1.000, 1.000, 1.000, respectively). The limits of agreement between SimK and TK, RK, TNP, TCPR, and EKR were 1.08, 1.08, 1.43, 1.48, and 1.73 D, respectively. All parameters showed good correlation with SimK, and the correlation coefficients were 0.995, 0.994, 0.983, 0.982, and 0.975.
Among the corneal power parameters after myopic keratorefractive surgery, the value of SimK is the largest, followed by TK and EKR, with TCRP, RK, and TNP being the smallest. The differences among the parameters may be attributable to the different calculation principles. Correct understanding and evaluation of corneal power parameters can provide a theoretical basis for taking advantage of the total corneal power to improve the accuracy of intraocular lens calculation after keratorefractive surgery.
分析近视角膜屈光手术后不同仪器所测角膜总屈光力参数之间的差异、一致性及相关性。
这项前瞻性横断面研究纳入了接受近视角膜屈光手术的患者，并在术后3个月测量其角膜屈光力。使用自动角膜曲率计测量模拟角膜曲率（SimK），基于扫频光学相干断层扫描（SS - OCT）的生物测量仪测量总角膜曲率（TK），眼前节光学相干断层扫描（anterior segment - OCT）测量实际角膜曲率（RK），以及Scheimpflug角膜曲率计测量真实净屈光力（TNP）、角膜总屈光力（TCRP）和等效角膜曲率读数（EKR）。分析这些参数之间的差异，并研究SimK与其他角膜总屈光力参数之间的一致性和相关性。
共纳入70例近视角膜屈光手术后患者的70只眼。所评估的角膜屈光力参数如下：SimK为38.32±1.93 D，TK为37.54±2.12 D，RK为36.64±2.09 D，TNP为36.56±1.97 D，TCRP为36.70±2.01 D，EKR为37.55±2.00 D。两两比较显示，除TK与EKR、RK与TNP、RK与TCRP之间（分别为1.000、1.000、1.000）外，所有参数之间均存在显著差异（<0.001）。SimK与TK、RK、TNP、TCPR和EKR之间的一致性界限分别为1.08、1.08、1.43、1.48和1.73 D。所有参数与SimK均显示出良好的相关性，相关系数分别为0.995、0.994、0.983、0.982和0.975。
近视角膜屈光手术后的角膜屈光力参数中，SimK值最大，其次是TK和EKR，TCRP、RK和TNP最小。参数之间的差异可能归因于不同的计算原理。正确理解和评估角膜屈光力参数可为利用角膜总屈光力提高角膜屈光手术后人工晶状体计算的准确性提供理论依据。
