Retrospective Analysis of Prediction Error of IOL Calculation in Large Population of Post-Myopic LASIK Patients Having Cataract Surgery
Narrative Responses:
Purpose
IOL power calculation has traditionally been very challenging in post-refractive surgery eyes. The purpose of this paper is to evaluate the impact of intraoperative aberrometry on the prediction error of power calculations for post-myopic LASIK eyes, based on retrospective review of a large number of such eyes.
Methods
Data for 1,104 post-myopic LASIK eyes undergoing cataract surgery with IOL power selection guided by intraoperative aberrometry were reviewed. The mean absolution value of the prediction error (MAVPE) was calculated and compared to the MAVPE that would have resulted from the IOL powers generated by the Haigis-L formula and the Shammas formula in these eyes.
Results
The prediction error (MAVPE) for 1,104 eyes was 0.43 D ± 0.42 D. The prediction error for the IOL powers selected by the Haigis-L formula would be 0.63 D ± 0.59 D and for those selected by the Shammas formula, 0.58 D ± 0.61 D. Distribution of the predicted spherical equivalent (SE) shows that 68% of the eyes were within 0.50 D of predicted SE, compared to 48% and 50%, respectively, if the IOL power had been selected by the Haigis-L and Shammas formulas.
Conclusion
The use of intraoperative aberrometry to guide IOL power selection reduces the prediction error and provides an improvement in the refractive outcomes of cataract surgery in challenging post-LASIK eyes.