This content is only available for ASCRS Members
This content from the 2020 ASCRS Virtual Annual Meeting is only available to ASCRS members. To log in, click the teal "Login" button in the upper right-hand corner of this page.
Filed Under
Cataract
Refractive
intraoperative aberrometry
post-refractive surgery
refractive outcomes
IOL power calculation
biometry
2020 paper presentation
Purpose
To assess the accuracy of intraoperative wavefront aberrometry (IWA) and modern intraocular lens (IOL) formulas including Hill-Radial Basis Function Version 2.0 (Hill-RBF), Barrett True K (BTK), Holladay 1 ± W-K adjustment, SRK/T, Haigis, and surgeon’s adjustment in post-refractive surgery patients undergoing cataract surgery.
Methods
Retrospective chart review. Thirty-four post-refractive eyes underwent cataract surgery with IWA from 05/2017 – 04/2019. Twenty-five eyes had prior myopic laser vision correction (LVC), 7 had hyperopic LVC, and 2 had radial keratotomy (RK). A capsular tension ring was placed in all eyes. Accuracy among ORA predictions and the above formulas for the chosen IOL was evaluated. Mean numerical error (MNE), mean absolute error (MAE), and percentages of prediction error within 0.25D, 0.50D, 0.75D, and 1.00D were calculated. Calculations were also performed for the percent of eyes with predicted hyperopic outcomes if the ORA-suggested versus the BTK-suggested IOL power were routinely selected.
Results
In post-myopic LVC eyes, MNE with ORA, BTK, Haigis, SRK/T, Hill-RBF, W-K adjusted Holladay 1, and surgeon’s adjustment were +0.172, -0.171, +0.212, +0.916, +0.792, +0.603, and +0.300 (F=8.49, p<0.001). MAE were 0.510, 0.503, 0.516, 1.00, 0.878, 0.668, and 0.611 (F=3.34, p<0.01), respectively. There was no difference in MNE (p=0.07) or MAE (p=0.95) between ORA-predicted and BTK in post-hoc analysis with Tukey HSD correction. If the ORA vs BTK-suggested IOL power were routinely selected, 28% and 16% of eyes would have projected hyperopic outcomes, respectively (p=0.31). In post-hyperopic LVC, MNE with ORA and BTK were -0.065 and 0.035 (p=0.83); MAE were 0.520 and 0.721 (p=0.53), respectively.
Conclusion
Our study suggests that in post-myopic and post-hyperopic LVC eyes undergoing cataract surgery with capsular tension rings, the accuracy of IWA and Barrett True K are comparable. BTK may yield fewer hyperopic surprises than ORA in post-myopic LVC eyes, though further studies with larger sample sizes are necessary.
To assess the accuracy of intraoperative wavefront aberrometry (IWA) and modern intraocular lens (IOL) formulas including Hill-Radial Basis Function Version 2.0 (Hill-RBF), Barrett True K (BTK), Holladay 1 ± W-K adjustment, SRK/T, Haigis, and surgeon’s adjustment in post-refractive surgery patients undergoing cataract surgery.
Methods
Retrospective chart review. Thirty-four post-refractive eyes underwent cataract surgery with IWA from 05/2017 – 04/2019. Twenty-five eyes had prior myopic laser vision correction (LVC), 7 had hyperopic LVC, and 2 had radial keratotomy (RK). A capsular tension ring was placed in all eyes. Accuracy among ORA predictions and the above formulas for the chosen IOL was evaluated. Mean numerical error (MNE), mean absolute error (MAE), and percentages of prediction error within 0.25D, 0.50D, 0.75D, and 1.00D were calculated. Calculations were also performed for the percent of eyes with predicted hyperopic outcomes if the ORA-suggested versus the BTK-suggested IOL power were routinely selected.
Results
In post-myopic LVC eyes, MNE with ORA, BTK, Haigis, SRK/T, Hill-RBF, W-K adjusted Holladay 1, and surgeon’s adjustment were +0.172, -0.171, +0.212, +0.916, +0.792, +0.603, and +0.300 (F=8.49, p<0.001). MAE were 0.510, 0.503, 0.516, 1.00, 0.878, 0.668, and 0.611 (F=3.34, p<0.01), respectively. There was no difference in MNE (p=0.07) or MAE (p=0.95) between ORA-predicted and BTK in post-hoc analysis with Tukey HSD correction. If the ORA vs BTK-suggested IOL power were routinely selected, 28% and 16% of eyes would have projected hyperopic outcomes, respectively (p=0.31). In post-hyperopic LVC, MNE with ORA and BTK were -0.065 and 0.035 (p=0.83); MAE were 0.520 and 0.721 (p=0.53), respectively.
Conclusion
Our study suggests that in post-myopic and post-hyperopic LVC eyes undergoing cataract surgery with capsular tension rings, the accuracy of IWA and Barrett True K are comparable. BTK may yield fewer hyperopic surprises than ORA in post-myopic LVC eyes, though further studies with larger sample sizes are necessary.
View More Presentations from this Session
This presentation is from the session "SPS-110 Post Refractive Surgery - IOL Calculations" from the 2020 ASCRS Virtual Annual Meeting held on May 16-17, 2020.