Department of Cataract and Refractive Lens Services, Narayana Nethralaya, Bengaluru, Karnataka, India.
Imaging, Biomechanics and Mathematical Modelling Solutions, Narayana Nethralaya, Bengaluru, Karnataka, India.
Indian J Ophthalmol. 2024 Aug 1;72(8):1210-1213. doi: 10.4103/IJO.IJO_2758_23. Epub 2024 Jul 29.
To evaluate the prediction accuracy of various intraocular lens (IOL) power calculation formulas on American Society of Cataract and Refractive Surgery (ASCRS) calculator and Barrett True-K total keratometry (TK) in eyes with previous laser refractive surgery for myopia.
This retrospective study included eyes with history of myopic laser refractive surgery, which have undergone clear or cataractous lens extraction by phacoemulsification followed by IOL implantation. Those who underwent uneventful crystalline lens extraction were included. Eyes with any complication of refractive surgery or those with eventful lens extraction procedure and those who were lost to follow-up were excluded. Formulas compared were Wang-Koch-Maloney, Shammas, Haigis-L, Barrett True-K no-history formula, ASCRS average power, ASCRS maximum power on the ASCRS post-refractive calculator and the IOLMaster 700 Barrett True-K TK. Prediction error was calculated as the difference between the implanted IOL power and the predicted power by various formulae available on ASCRS online calculator.
Forty post-myopic laser-refractive surgery eyes of 26 patients were included. Friedman's test revealed that Shammas formula, Barrett True-K, and ASCRS maximum power were significantly different from all other formulas (P < 0.00001 for each). Median absolute error (MedAE) was the least for Shammas and Barrett True-K TK formulas (0.28 [0.14, 0.36] and 0.28 [0.21, 0.39], respectively) and the highest for Wang-Koch-Maloney (1.29 [0.97, 1.61]). Shammas formula had the least variance (0.14), while Wang-Koch-Maloney formula had the maximum variance (2.66).
In post-myopic laser refractive surgery eyes, Shammas formula and Barrett True-K TK no-history formula on ASCRS calculator are more accurate in predicting IOL powers.
评估各种眼内晶状体（IOL）计算公式在接受过近视激光矫正手术的患者中的预测准确性，这些患者接受了超声乳化白内障吸除术联合 IOL 植入术或白内障晶状体切除术。
这是一项回顾性研究，纳入了有近视激光矫正手术史的患者，这些患者接受了超声乳化白内障吸除术联合 IOL 植入术或白内障晶状体切除术。研究纳入了无并发症的晶状体切除术患者。排除了有屈光手术并发症、晶状体切除术过程中出现并发症或失访的患者。比较的公式包括 Wang-Koch-Maloney、Shammas、Haigis-L、Barrett True-K 无历史记录公式、ASCRS 平均功率、ASCRS 最大功率（基于 ASCRS 屈光手术后计算器）和 IOLMaster 700 Barrett True-K 总角膜曲率（TK）。预测误差的计算方法为各公式预测的 IOL 屈光力与实际植入的 IOL 屈光力之间的差值。
共纳入 26 例患者的 40 只接受过近视激光矫正手术后的眼。Friedman 检验表明，Shammas 公式、Barrett True-K 和 ASCRS 最大功率与其他所有公式均有显著差异（每种公式 P < 0.00001）。Shammas 和 Barrett True-K TK 公式的中位绝对误差（MedAE）最小（分别为 0.28 [0.14，0.36] 和 0.28 [0.21，0.39]），Wang-Koch-Maloney 公式的 MedAE 最大（1.29 [0.97，1.61]）。Shammas 公式的方差最小（0.14），而 Wang-Koch-Maloney 公式的方差最大（2.66）。
在接受过近视激光矫正手术的患者中，Shammas 公式和 ASCRS 计算器上的 Barrett True-K TK 无历史记录公式在预测 IOL 屈光力方面更为准确。
