Langenbucher Achim, Szentmáry Nóra, Wendelstein Jascha, Cayless Alan, Fassbind Benj, Hoffmann Peter
Department of Experimental Ophthalmology, Saarland University, Homburg, Saar, Germany.
Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg, Saar, Germany.
Acta Ophthalmol. 2025 Aug;103(5):e298-e309. doi: 10.1111/aos.17491. Epub 2025 Mar 29.
To design a vergence-based lens power formula based on the classical Haigis formula for better outcomes while retaining the original formula architecture.
Four new formula variants (A-D) incorporating a sum of segments correction for axial length, harmonic mean of corneal radii instead of arithmetic mean (all variants), and differing combinations of lower keratometer index (C, D) and an additional term (a3) representing the lens thickness in the effective lens position (B, D) were assessed in an analysis based on four datasets of IOLMaster 700 biometric data for eyes treated with the Hoya Vivinex lens (dataset 1), Alcon SA60AT lens (2), Johnson & Johnson ZCB00 lens (3), and the Bausch & Lomb MX60 lens (4). All parameters (formula constants and keratometer index) were calculated by nonlinear iterative optimisation techniques for minimising the root mean squared prediction error (RMSPE). Performance was assessed in terms of the final RMSPE.
All four variants showed reductions in RMSPE ranging from 2.8% to 12.6% over the original Haigis formula. For each of the four datasets, variants B and D (with the additional a3 constant) performed better in this respect than variants A and C. In all four cases, variants C and D (with the adjusted keratometer index) performed slightly better than A and B, respectively.
Although not amenable to statistical analysis, the % improvements in RMSPE would appear to be clinically relevant. However, the benefit has to be proven in a prospective multicentric study with a large sample size.
基于经典的海吉斯公式设计一种基于聚散度的透镜屈光力公式，以获得更好的结果，同时保留原始公式结构。
在一项分析中，对四个新的公式变体（A-D）进行了评估，这些变体纳入了眼轴长度的分段校正总和、角膜半径的调和平均值而非算术平均值（所有变体），以及不同组合的较低角膜曲率计指数（C、D）和一个代表有效晶状体位置的晶状体厚度的附加项（a3）（B、D）。该分析基于四个数据集，这些数据集来自使用豪雅Vivinex晶状体（数据集1）、爱尔康SA60AT晶状体（2）、强生ZCB00晶状体（3）和博士伦MX60晶状体（4）治疗的眼睛的IOLMaster 700生物测量数据。所有参数（公式常数和角膜曲率计指数）通过非线性迭代优化技术计算，以最小化均方根预测误差（RMSPE）。根据最终的RMSPE评估性能。
与原始海吉斯公式相比，所有四个变体的RMSPE均降低了2.8%至12.6%。对于四个数据集中的每一个，变体B和D（带有附加的a3常数）在这方面的表现优于变体A和C。在所有四种情况下，变体C和D（调整后的角膜曲率计指数）的表现分别略优于A和B。
虽然无法进行统计分析，但RMSPE的百分比改善似乎具有临床相关性。然而，这种益处必须在一项大样本量的前瞻性多中心研究中得到证实。
