AIM: To evaluate the predictability of Olsen formula for postoperative refractive power in patients with high myopia complicated with cataract.

METHODS: This retrospective study reviewed 65 patients(101 eyes)with high myopia and who had phacoemulsification combined with intraocular lens implantation from October 10^th 2016 to August 20^th 2019 in our hospital. They were divided into three groups according to the axis length: group A(26mm 30mm)22 cases(31 eyes). The postoperative theoretical diopter(that is, the preoperative predictive diopter of each formula corresponding to the degree of IOL implanted)of intraocular lens was calculated by SRK/T, Haigis and Olsen formulas of IOL-master. The actual postoperative 3mo diopter was recorded and the absolute refractive error(MAE)was calculated.

RESULTS: The postoperative 3mo MAE in the three groups calculated with Olsen formula was 0.15(0.04, 0.22), 0.19(0.14, 0.27), 0.26(0.115, 0.455)D respectively(P>0.05). For patients with the same axial length, the postoperative 3mo MAE of Olsen formula was the smallest. The Bland-Altman method was used to analyze the consistency between the postoperative theoretical diopter and the postoperative 3mo actual diopter. The results showed that the postoperative 3mo actual diopter was the closest to the postoperative theoretical diopter of the Olsen formula, while the postoperative theoretical diopter of the SRK/T formula was the worst.

CONCLUSION: For patients with high myopia and cataract, the accuracy and stability of Olsen formula is better than that of SRK/T and Haigis formula, and Olsen formula is least affected by eye axis length.