Abstract
Purpose :
To evaluate the difference in contrast sensitivity between one versus two measurements after lenticule removal procedure with a new femtosecond laser (nFS) system.
Methods :
A prospective, multicenter, open-label, bilateral lenticule removal clinical study for myopic correction was performed. One hundred and twenty (120) subjects were treated with mean age of 26.6±5.9 SD. For each subject, a lenticule was created in both eyes using an nFS laser and was then removed for vision correction. Mean pre-op MRSE was -4.20D and ranged from -1.25D to -9.63D. Contrast sensitivity (CS) data was measured at pre-op, and then starting at the 3-month post-op visit. CS was measured and repeated twice in mesopic conditions with and without glare at 1.5, 3.0, 6.0, and 12.0 cpd; and in photopic conditions with no glare at 3.0, 6.0, 12.0. and 18.0 cpd. MRSE and monocular UCVA and BSCVA were assessed at those time points.
Results :
No significant difference in CS was found between the average of two repeated tests and the first set of testing alone for all but two light conditions and spatial frequencies. At 6-month post-operatively, there was a statistical difference of 0.04 log units (mesopic with no glare at 3 cpd), and 0.05 log units (mesopic with glare at 12 cpd) which are smaller than 0.3 log units, the clinically significance threshold.
Preoperatively, the mean CS for the photopic with no glare at 18 cpd was 1.36 log units for both the average of the repeated and only first measurement set. CS was 1.36 vs. 1.35, 1.45 vs. 1.45, 1.47 vs. 1.50, and 1.52 vs. 1.52 log units at 3-, 6-, 9-, and 12-month post-op between the average of repeated versus only first measurement, respectively.
Mean MRSE was -0.27D and -0.31D at the 3- and 6-month post-op visits, and monocular UCVA/BSCVA was 20/20 or better for 93%/100% eyes at 3-month respectively, and 94%/99% of eyes at 6-month post-op, respectively.
Conclusions :
In this study, there was no significant difference in CS between the average of the repeated versus only the first measurement set after myopic refractive lenticule procedure. For the photopic condition at 18 cpd there was a general increase at post-op visits in CS compared to pre-op, however, the increases were not statistically significant. The good visual outcomes demonstrate that lenticule removal procedure with the nFS is safe and effective.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.