Accuracy of 10 Intraocular Lens Power Calculation Formulas

Purpose : to access accuracy of 10 intraocular lens (IOL) calculation formulas. Patients and methods . 784 patients (784 eyes) formed study group. Every patient underwent phacoemulsification (PE) with IOL implantation. Biometry for IOL calculation was performed on IOL-Master 500 and 700 (Carl Zeiss, Germany). 1 month after PE spherical equivalent of refraction (Topcon-8800, Japan) was assessed. To compare refractive results of formulas, mean calculation error (ME), mean absolute calculation error (MAE) and formula performance index (FPI) were assessed. Results . The following formulas are presented in descending order of the FPI: Kane (10.20), Hill RBF (10.00), Barrett (9.62), Holladay I (9.52), Hoffer QST (9.26), Ladas Super Formula (9.17), EVO (9.09), Hoffer Q (8.40), SRK/T (8.13), Pearl DGS (8.00). The lowest MAE shows Kane formula (0.33 ± 0.25), Hill RBF (0.33 ± 0.24) and Barrett (0.34 ± 0.25). The greatest MAE — SRK/T (0.36 ± 0.27), Hoffer Q (0.36 ± 0.25) and Pearl DGS (0.39 ± 0.37). Conclusion . The highest accuracy was demonstrated by Kane, Hill RBF and Barrett formulas, however, other formulas (SRK/T, Holladay I, Hoffer Q, Ladas Super Formula, EVO, Hoffer QST, Pearl DGS) demonstrate comparable results with the above.