Comparing the accuracy of different intraocular lens power calculation formulas using IOL-Master 700

Abstract

Abstract Purpose: The aim of this study was to compare the accuracy of different IOL power calculation formulae in the IOL-Master 700 and to establish the impact of ACD on different IOL power calculation formulae in intermediate eyes. Methods: A total of 80 patients who underwent uncomplicated phacoemulsification surgery between July 2020 and June 2022 were analyzed retrospectively. Eight formulae (SRK/T, Hoffer Q, Haigis, Holladay 2, Kane, Barrett Universal II, T2, and the Ladas Super Formula) were compared. Results: This study included 113 eyes. SRK/T achieved the lowest MAE (0.30D), MedAE (0.25D), SD of prediction error (0.33), and the greatest percentage of eyes within ±0.25D (50.4%), ±0.50D (83.2%), and ±1.00D (100%). According to the percentage of eyes within ±0.50D, Kane showed better results than Barret Universal II (82.3% vs 79.6%) while traditional formulae (Holladay 2, Hoffer Q, and Haigis) had poor refractive outcomes in comparison to the new generation formulae. For the shallow ACD group, the lowest MAE and MedAE were noted in the Barrett Universal II formula (MAE= 0.26D, MedAE= 0.20D) while the highest percentage of eyes within ±0.50D was observed in the Ladas Super Formula (87.1%). There were no statistically significant differences between the formulas in normal and deep ACD groups. Conclusion: SRK/T was the most accurate formula for the overall study, followed by new-generation formulae. For normal and deep ACD groups all eight formulae had similar results while for the shallow ACD group Barrett Universal II and the Ladas Super Formula performed better.