Accuracy Of Newer I O L Power Formulas In Short And Long Eyes Using Sum-Of-Segments Biometry

To analyze the accuracy of newer IOL power formulas in long and short eyes measured by the sum-of-segments biometry.

Private practice, Lynwood, California, USA.

595 eyes scheduled for cataract surgery had their eyes measured using the sum-of-segments biometry. The expected residual refractions were calculated using Barrett Universal II (BII), Barrett True Axial Length (BTAL), Emmetropia Verifying Optical (EVO), Hill-RBF, Hoffer QST, Holladay 2, Holladay 2 NLR, K6, Kane, Olsen, PEARL-DGS, T2 and VRF formulas, and compared to the traditional Haigis, Hoffer Q, Holladay 1 and SRK/T formulas.

In the 102 long eyes, all new formulas had a mean absolute error (MAE) equal or lower than the traditional formulas, ranging from 0.29 to 0.32 D. In the 78 short eyes, BTAL, EVO K6, Olsen and Pearl-DGS formulas had the lowest MAE (0.33D, 0.33D, 0.31, 0.32D, 0.32D respectively), while all traditional formulas exceeded 0.36 D.

All new formulas performed equal or better than the traditional formulas with the sum-of-segments biometry, with no statistical differences between them in the long eyes. In the short eyes, the best results were obtained with the BTAL, EVO, K6, Olsen and PEARL-DGS formulas.