Comparison of Early Experience With Intraoperative Wavefront Aberrometry IOL Power Calculations in Laser-Assisted Versus Conventional Cataract Surgery
Narrative Responses:
Purpose
To compare the preoperative IOL calculations with intraoperative IOL power measurements made by ORA on eyes pretreated with a femtosecond laser and those that were not.
Methods
This was a retrospective study of aphakic intraoperative wavefront IOL power calculations in eyes that underwent conventional cataract surgery (n=45) and laser assisted cataract surgery with either a B+L Victus or LenSx femtosecond laser (n=53). Each eye had a postoperative target of plano and received a B+L MI60L lens. Preoperative IOL calculations were compared to ORA measurements.
Results
The mean difference between preoperative and intraoperative IOL calculations in the femtosecond group was -0.37D ±0.53D (p=0.013). For the conventional surgery group there was a mean difference of -0.1D ±0.67D (p= 0.32). Postoperative manifest refraction showed the mean spherical equivalence of the femto group to be -0.251 D ± 0.39D and the non-femto group to be -0.248 D ± 0.41D (p=0.48). Using the implanted power, the ORA suggested power, and the POMR, the mean postoperative spherical equivalences were -0.66D +/- 0.62D in the femto group and -0.47D +/- 0.60D for the non-femto group (p=0.058).
Conclusion
Preoperative and intraoperative IOL calculation may differ significantly when the eyes are pretreated with a femtosecond laser. Relying heavily on intraoperative measurements for lens selection may lead to a higher rate of postoperative myopia in femtosecond laser assisted cataract surgery if variables are not controlled.