Intraocular lens formula comparison in axial hyperopia with a high-power intraocular lens of 30 or more diopters

Purpose: To compare the accuracy of intraocular lens (IOL) power calculation formula predictions (Barrett Universal II, Emmetropia Verifying Optical [EVO] 2.0, Haigis, Hill-RBF 2.0, Holladay 1, Holladay 2, Hoffer Q, Kane, Olsen, and SRK/T) when using the Alcon SA60AT IOL of 30 or greater diopter (D) power. Setting: Kaiser Permanente, California, USA. Design: Multicenter retrospective consecutive case series. Methods: Data from patients having uneventful cataract surgery with insertion of a ≥30 D SA60AT IOL and preoperative LENSTAR 900 biometry were included. A single eye per qualifying patient was randomly selected for inclusion in the analysis. Lens constants were optimized using a large dataset of the same IOL model including the full range of axial lengths. The optimized lens constants were then used to calculate the predicted refraction for each formula, which was compared with the actual refractive outcome to give the prediction errors. Results: Included in the study were 182 eyes of 182 patients. From highest to lowest, the percentage of eyes with a prediction error within ±0.50 D was the Kane (58.8%), EVO 2.0 (57.7%), Haigis (55.5%), Holladay 2 (54.9%), Olsen (53.3%), Holladay 1 (50.5%), Hill-RBF 2.0 (43.9%), SRK/T (42.9%), Barrett Universal II (36.8%), and Hoffer Q (35.7%) formulas. The Kane formula had a statistically significant lower mean absolute prediction error compared with all formulas ( P < .05) except the EVO 2.0 formula. Conclusions: The Kane formula had the lowest prediction error of the formulas studied, which was statistically significant compared with all formulas except the EVO 2.0 formula.