Seven-Year Refractive Outcomes Comparing Small Incision Lenticule Extraction And Femtosecond Laser-Assisted In Situ Keratomileusis For Myopia And Myopic Astigmatism

This study aimed to compare the seven-year refractive outcomes of small incision lenticule extraction (SMILE) and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) for correction of myopia and myopic astigmatism.

This is a retrospective cohort study. This study included 97 eyes of 53 patients who had undergone SMILE or FS-LASIK for myopia seven years prior. Evaluated the efficacy and safety of both surgeries.

This study included 97 eyes from 53 myopic patients. The evaluation was performed at baseline and postoperatively at 7 years. The patients all measured parameters included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and manifest refraction before and after surgery. And calculate the efficacy and safety index of both surgeries.

There were no significant differences between the SMILE and FS-LASIK groups in logMAR UDVA, cylinder, and logMAR CDVA at 7 years postoperatively (P＞0.05). However, there were significant differences between the two groups in sphere and spherical equivalent (P=0.035 and P=0.016, respectively). UDVA was better than or equal to 20/20 in 81% of the eyes after SMILE and in 63% after FS-LASIK (P = 0.045). The efficacy indices of the SMILE and FS-LASIK groups were 1.04 ± 0.23 and 0.97 ± 0.23 (P=0.405), and the safety indices were 1.18 ± 0.19 and 1.10 ± 0.17 (P=0.543), respectively.

This study demonstrates the good predictivity of both SMILE and FS-LASIK. SMILE could offer superior refractive outcomes than FS-LASIK during a 7-year follow-up in correcting myopia and myopic astigmatism.