Comparing Intraoperative Wavefront Aberrometry With Different IOL Power Calculation Methods in Patients With Prior Myopic Refractive Surgery
Narrative Responses:
Purpose
To evaluate three different surgeons method of calculating pre-operative IOL power in post-refractive patients and to compare each method to intraoperative wavefront aberrometry.
Methods
A retrospective study of 24 eyes was conducted analyzing the refractive outcomes in patients having undergone cataract surgery. All patients had a history of prior myopic refractive surgery.
Surgeon 1 selected IOL power predicted by the ASCRS website with no historical data. Surgeon 2 selected IOL power predicted by the ASCRS website with historical data. Surgeon 3 selected IOL power based on average keratometry readings from Orbscan topography which were plugged into the Holladay 2 formula.
Post-operative spherical equivalent was then used to determine the accuracy of intraoperative wavefront aberrometry versus the pre-operative method chosen by each surgeon.
Results
*Preliminary
Average difference between pre-operative IOL power and ORA suggested IOL power
Surgeon 1: 0.50D
Surgeon 2: 0.67D
Surgeon 3: 1.14D
ORA Accuracy: Difference between predicted Spherical Equivalent of Implanted IOL and Post-Operative Spherical Equivalent
Surgeon 1 (n=5)
Within 0.25D: 40%
Within 0.50D: 60%
Within 0.75D: 80%
Within 1.0D: 80%
Surgeon 2 (n=12)
Within 0.25D: 33%
Within 0.50D: 67%
Within 0.75D: 83%
Within 1.0D: 100%
Surgeon 3 (n=7)
Within 0.25D: 0%
Within 0.50D: 0%
Within 0.75D: 14%
Within 1.0D: 43%
*data for pre-operative methods pending
Conclusion
*Final conclusion pending
Preliminary conclusions: Surgeon 1 and 2's method for selecting pre-operative IOL power (ASCRS website) more closely correlates with the IOL power suggested by the ORA than Surgeon 3's pre-operative method. Surgeon 1 and 2's method may be more accurate in predicting post-operative spherical equivalent.