Precision in Intraocular Lens Calculation for Chinese Cataract Patients with Prior History of Radial Keratotomy

Purpose: To evaluate the predictive accuracy of eight traditional and contemporary intraocular lens (IOL) power calculation formulas in Chinese cataract patients with prior radial keratotomy (RK). Patients and Methods: RK patients who underwent phacoemulsification with IOL implantation were retrospectively recruited. Refractive prediction errors (RPE)were calculated for eight formulas: Haigis-L, Shammas, Barrett True-K, Camellin Calossi Camellin (CCC), Kane, EVO, Pearl-DGS, and Jin-AI. The study compared RPE, mean absolute error (MAE), median absolute error (MedAE), and percentages of eyes achieving prediction errors within ±0.25, ±0.50, ±0.75, ±1.0, and ±2.0 diopters. Results: This retrospective study analyzed 34 eyes from 21 patients with prior RK surgery. The superior performing IOL power calculation formulas were Jin-AI (MAE = 0.64 D, MedAE = 0.49 D), Barrett True-K (MAE = 0.58 D, MedAE = 0.535 D), and EVO (MAE=0.59 D, MedAE = 0.538 D). These three formulas demonstrated comparable accuracy, with 47.1%, 44.1%, and 44.1% of eyes achieving prediction errors within ±0.50 D, respectively. The Haigis-L and Pearl-DGS formulas exhibited significantly higher prediction errors in eyes with more than 12 RK incisions. Conclusion: The Jin-AI, Barrett True-K, and EVO formulas demonstrated superior accuracy for IOL power calculation in Chinese cataract patients with prior RK. The Jin-AI formula, a novel artificial intelligence-based formula derived from Chinese individuals, presents a promising option for post-RK IOL calculation, while external validation studies across diverse ethnic groups are essential.