Randomized Prospective Comparison of Toric IOL Power and Axis Determination by Intraoperative Aberrometry Versus Toric Calculator
Purpose
To compare the accuracy of toric IOL power and axis determination using two methods: intraoperative wavefront aberrometry vs the manufacturer-provided toric IOL calculator.
Methods
In this randomized, prospective, observer-masked, contralateral eye study, 124 subjects underwent femtosecond laser-assisted cataract surgery with phacoemulsification in both eyes, 1 to 2 weeks apart. All eyes were implanted with Alcon Acrysof Toric IOLs. The first eye of each subject was randomized to the study group (WaveTec ORA System with VerifEye used to calculate IOL power and axis intraoperatively) or the control group (Alcon Acrysof Toric Calculator used to determine power and axis preoperatively). Subjects were evaluated at 1 month. The primary endpoint is the percentage of eyes with postoperative astigmatism ≤ 0.50 D. A secondary endpoint is the mean postoperative astigmatism.
Results
Thus far, 111 bilaterally implanted subjects are available for analysis. The percentage of eyes with postoperative refractive astigmatism ≤ 0.50 D is 89.2% in the study group and 76.6% in the control group (p=0.006). Mean postoperative astigmatism is 0.29 ± 0.28 D in the study group vs. 0.36 ± 0.38 D in the control group (p=0.041).
Conclusion
ORA intraoperative aberrometry provides more accurate toric lens guidance (cylinder power and axis) and is more likely to reduce the postoperative astigmatism to ≤ 0.50 D than the toric calculator. The differences between the two groups are statistically significant.