Early Visual Recovery And Energy Settings After Small-Incision Lenticule Extraction Using The Visumax 800 In A Post-Market Clinical Follow-Up Study

Subjects with myopia up to 10 D and astigmatism up to 5 D underwent SMILE using the VISUMAX 800 laser (Carl Zeiss Meditec AG) in a prospective, non-randomized, multi-center, international clinical follow-up study. Individual laser settings were optimized on a site-by-site basis. The range of spot/track settings at 5 investigational sites varied from 2.2/2.2µm to 4.5/4.5µm, while the energy varied from 93 ± 4.5 nJ to 130.5± 4 nJ. Energy per µm² was calculated for each site and related to visual recovery as well as to the ease of dissection on a scale from 0-10. Patients were examined at 1‑day, 1-week, 1-month, 3-months, and 6-months after treatment. 1-day and 1-week data of eyes targeted at plano were used to evaluate early visual recovery.

Out 473 eyes (237 subjects) treated 290 eyes with preoperative CDVA of 20/20 or better were aimed for plano. At the 1-day and 1-week postoperative visit, UDVA was 20/20 or better in 71.4% and 86.3%  while 20/32 or better was achieved in 97.9% and 98.9% of eyes, respectively. The average energy per area varied between 18.8 nJ/µm and 6.7 nJ/ µm² between the tightest and the widest spot spacing sites with other sites being in-between. While the dissection was easiest with the tight spot/lower energy setting (score 9.5 compared to 7) the early visual recovery - albeit non-significant – was highest with the wide spacing/higher energy.

Overall, patients undergoing SMILE with the VISUMAX 800 had quick visual recovery with a vast majority of eyes seeing 20/20 as early as one day after surgery. As expected, the separability of the lenticule improved with the lenticule energy/area. However, the early visual acuity had the tendency to non-significantly decrease with the higher energy settings/area (less than one Snellen line).