Clinical feasibility of the ESCRS IOL power calculator.

PURPOSE: To assess the mean absolute error (MAE) of classic and modern intraocular lens (IOL) power calculation formulas to evaluate the feasibility of the ESCRS IOL Calculator.

SETTING

Department of Ophthalmology, Johannes Kepler University and Kepler University Clinic, Linz, Austria; Department of Ophthalmology, Medical University Graz, Graz, Austria.

METHODS

337 eyes of 337 patients who underwent implantation of a monofocal IOL (PCB00) were included in this study. The classic IOL calculation formulas output by the biometry device (Barrett Universal II [BUII], Haigis, SRK/T, and HofferQ) and modern formulas implemented in the ESCRS calculator (BUII, Cooke K6, EVO, Hill-RBF, Hoffer QST, Kane, and Pearl-DGS) were evaluated. The MAE, the number of eyes within ±0.5, ±1.0, ±1.5, ±2.0 diopters (D) of the target refraction, the agreement between ESCRS formulas on the proposed IOL power, and the time factor for the input in the ESCRS calculator were evaluated.

RESULTS

The best performing ESCRS calculator formulas were Kane, EVO, and BUII with a MAE (SD) of 0.37 (0.30) D, 0.37 (0.32) D, and 0.38 (0.32) D. A lower, but not significant difference in MAE for ESCRS formulas compared with biometry formulas was observed. A significant difference was observed between Hoffer QST and all other formulas (P < .01 for all). After excluding Hoffer QST, testing revealed a significant difference between ESCRS and biometry formulas (P = .004).

CONCLUSIONS

The ESCRS calculator allows efficient and up-to-date IOL calculations in routine clinical practice. The predictive accuracy of the ESCRS calculator is superior compared with older biometric formulas.