Materials and Methods: This retrospective study included 70 eyes of 38 patients who underwent uneventful phacoemulsification with multifocal IOL (AcrySof IQ PanOptix) implantation. IOL power calculations were performed using Pentacam Oculus AXL optical biometer. Postoperative actual refractive errors and errors predicted by the Barrett Universal II, Olsen, SRK/T, Holladay 1, Hoffer Q and Haigis formulas were analyzed. The mean estimation error (EE), mean absolute estimation error (AEE) and the percentage of eyes within ±0.50 and ±1.00 D of target refraction of for each of six formulas were calculated and compared in three groups formed based on the axial length(AL) (Group 1: <22.5mm, Group 2: 22.5-24mm, Group 3: >24mm).

Results: In overall study group, the smallest mean AEE was provided by Barrett Universal II formula, with no statistically significant difference (p=0.23). The highest percentage of eyes within ±0.50 and ±1.00 D of target refraction was also found by using Barrett Universal II (78% and 95%). SRK/T provided smallest mean AEE for group 1(p=0.42). In Group 2, the smallest mean AEE was obtained by using Barrett Universal II (p=0.10). In group 3, Haigis provided smallest mean AEE (p=0.14).

Conclusions: Based on the Pentacam Oculus AXL biometric data, better results obtained using SRK/T formula in eyes with short AL. Barrett Universal II formula can be preferred in eyes with moderate AL, and Haigis formula in eyes with long AL. Keywords : Pentacam Oculus AXL, axial length, multifocal IOL power, calculation formulas