Comparative evaluation of refractive outcomes after implantation of two types of intraocular lenses with different diopter intervals (0.25 diopter versus 0.50 diopter)

BACKGROUND: Intraocular lenses (IOLs) with different diopter (D) intervals may have different tolerance, and may provide different accuracy of refractive outcome after cataract surgery. The aim of the study is to compare the accuracy of refractive outcome after implantation of IOLs with different D intervals after cataract surgery. METHODS: A total of 80 eyes from 40 patients who underwent phacoemulsification with implantation of a 0.50 D interval Akreos AO IOL in one eye and a 0.25 D interval Softec HD™ IOL in the other eye were enrolled. The percentages of eyes with refractive prediction error within ±0.50 D at one month after surgery were compared. To evaluate the effect of the dioptric errors of the IOL itself on refractive prediction error, the percentage of eyes with refractive prediction error within ±0.25 D of the IOL with a standard deviation (SD) of ±0.40 D was compared with that of the IOL with a SD of ±0.11 D through Monte Carlo simulations. RESULTS: In this clinical study, the percentage of eyes with refractive prediction error within ±0.50 D by the Haigis formula in the Softec HD™ group (85.0%) was significantly greater than that in the Akreos AO group (57.5%; P = 0.027). In Monte Carlo simulations, all percentages of eyes with refractive prediction error within ±0.25 D by the Haigis and SRK/T formulas in the Softec HD™ group were significantly greater than those in the Akreos AO group. CONCLUSIONS: The IOL with a 0.25 D interval was more accurate than the IOL with a 0.50 D interval in predicting refractive outcome after cataract surgery. TRIAL REGISTRATION: Current Controlled Trials KCT0002192, Retrospectively registered (Date of registration: 6 January 2017).