Comparison of Corneal Astigmatism in Cataract Eyes Obtained From Intraoperative Aberrometry and From Other Devices
Narrative Responses:
Purpose
To assess the agreement of corneal astigmatism measurements in normal eyes using Optiwave Refractive Analysis (ORA, Wavetech), IOL master (Zeiss), Lenstar (Haag Streit), Atlas topography (Zeiss), Galilei tomographer (Ziemer), and Cassini topographer (I-optics).
Methods
In this prospective comparative study, three sets of keratometric measurements were obtained by a single observer. Preoperative data were collected using the IOL master, Lenstar, Atlas, Galilei and Cassini. ORA measurements were obtained intraoperatively. Analysed parameters were astigmatism magnitude and axis, and J0 and J45 vectors. Measurement repeatability was evaluated by means of coefficient of variation, within-subject standard deviation and intraclass correlation coefficient. The Bland and Altman plots were utilized to assess measurement agreement between two devices.
Results
Preliminary data were analyzed (n = 21). Mean corneal astigmatism preoperatively was as follows: Lenstar 0.71 D at 96 degrees, IOL Master 1.66D at 44.02 degrees, Atlas 0.82 D at 90 degrees, Galilei 0.83 D at 90 degrees, and Cassini 0.62D at 28.31 degrees. Intraoperative aphakic ORA revealed expected residual astigmatism of 1.27 D at 104 degrees (p>0.05 for magnitude and axis compared to other devices.
Conclusion
In this preliminary study, there was minimal correlation between intraoperative aberrometry and other devices in regards to astigmatism magnitude and axis. A larger cohort may yield improved results.