Bilateral Lenticule Creation Followed by Bilateral Lenticule Separation Improves Visual Outcomes After SMILE

To explore the impact of different surgical sequences on the visual and refractive outcomes of bilateral small incision lenticule extraction (SMILE) surgery using propensity score matching (PSM) analysis.

Participants who underwent uneventful SMILE between March 2018 and September 2019 were retrospectively analyzed and were divided into two groups: Sequence A (laser scanning [LS] of the right eye, manual separation lenticule [MSL] of the right eye, and LS and MSL of the left eye) and Sequence B (LS of the right eye, LS of the left eye, MSL of the left eye, and MSL of the right eye). PSM was conducted to minimize the effect of confounding factors on postoperative visual outcomes at days 1 and 7 and months 1, 3, and 6. Safety, efficacy, predictability, and stability were compared between groups.

Overall, 1,854 eyes of 927 participants were included (Sequence A, n = 280; Sequence B, n = 647). After PSM, there were no significant differences in baseline characteristics, and 534 eyes (267 patients) in the Sequence A group were matched (1:1) to the Sequence B group. The postoperative corrected distance visual acuity significantly differed between groups at 3 months (adjusted P = .007). The uncorrected distance visual acuity significantly differed between groups at all follow-up visits (adjusted P < .01). The safety index (1.341 ± 0.265 and 1.413 ± 0.294) and efficacy index (1.173 ± 0.191 and 1.251 ± 0.269) were different in the Sequence A and Sequence B groups, respectively, at 3 months (adjusted P < .01). No difference in visual outcomes was found between right and left eyes.

Patients who had bilateral lenticule creation followed by bilateral lenticule separation had better postoperative visual outcomes than those who underwent complete SMILE surgery in each eye separately. Regardless of the surgical sequence chosen for the SMILE procedure, there was no impact on outcomes between the right and left eyes. Adjusting the sequence of the surgical procedure may be a way to improve the visual results. [.