Abstract
Purpose :
The new femtosecond laser system (nFS) utilizes ultralow energy per pulse and contiguous focus spots to create tissue-bridge-free incisions with minimal disruption to adjacent tissue. The purpose of this clinical trial was to evaluate visual outcomes of the nFS for the correction of compound myopic refractive errors. Surgeon’s also assessed ease of lenticule removal. The primary clinical hypothesis was that the lenticule removal procedure using the nFS would result in consistent, safe, and effective visual outcomes.
Methods :
This prospective, multicenter, single-arm, open-label clinical study was conducted at four sites (2 in India and 1 each in Singapore and Croatia). Clinical examination of each eye was performed pre-operatively and at all follow-up visits: 1-day, 1-week, and 1-, 3-, 6-, 9- and 12-months. The proportion of eyes with each rating of ease lenticule removal, UCVA and BCVA are presented over time. Summary statistics were calculated for manifest refractions spherical equivalent (MRSE).
Results :
A total of 240 eyes were treated during the study. Data from 238, 237, 224, 216, 162, 128 and 122 eyes were available from the 1-day, 1-week, 1-, 3-, 6-, 9- and 12-month visits, respectively.
The preoperative mean MRSE was - 4.20 diopters (D) ± 1.53 D (range -9.63 D to -1.25 D). The mean MRSE at 1 week, and 1, 3, 6, 9 and 12 months post-op was -0.34 D ± 0.34 D, -0.28 D ± 0.35 D, -0.27 D ± 0.33 D, -0.31 D ± 0.27 D, -0.35 D ± 0.23 D and -0.35 D ± 0.23 D, respectively. MRSE within ±0.50 D was achieved in 82%, 85%, 91%, 91%, 88% and 89% of eyes at the same visits.
For lenticule removal, surgeons reported a favorable response of no to mild dissection needed in 86.1% (204/237) of the eyes. 30/237 eyes (12.7%) required moderate dissection. Only 3/237 eyes (1.3%) required significant dissection and no eyes were scored as unable to dissect. Monocular UCVA was 20/20 or better in 63%, 78%, 86%, 93%, 94%, 95% and 97% of eyes at 1 day, 1 week and 1, 3, 6, 9 and 12 months post-op, respectively. BCVA of 20/20 or better was achieved in 100% of eyes starting from the 3-month post –op visit.
Conclusions :
In this study, the nFS delivered consistent, safe, and effective treatment of myopic refractive errors with and without astigmatism over 12 months. Low pulse energy enabled easy lenticule removal with minimal tissue manipulation promoting fast visual recovery, and excellent visual outcomes.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.