Matched comparison of corneal higher order aberrations induced by SMILE to femtosecond assisted LASIK and to PRK in correcting moderate and high myopia: 3.00mm vs. 6.00mm

Abstract

Background The refractive surgeries induce corneal higher order aberrations (C-HOAs). In this study, change of C-HOAs after small-incision lenticule extraction (SMILE) compared to femtosecond assisted laser in situ keratomileusis (femto-LASIK), and to photorefractive keratectomy with mitomycin-C (PRK) under photopic and mesopic conditions. Methods In this prospective study, age, gender, and apical corneal thickness (ACT) matched cases with moderate myopia [spherical equivalent (SE) 3.00 to 6.00D) to high myopia (SE > 6.00D)] were enrolled. In addition to visual acuity and refraction, total C-HOA, coma, spherical aberration (SA), and trefoil in the 3- and 6-mm zones were measured before and 3 and 6 months after surgery. Results Overall, 372 moderate myopia cases (124 eyes of 124 individuals in each surgical group) and 171 high myopia cases (57 eyes of 57 individuals in each surgical group) were enrolled. At baseline, the differences in age, gender, ACT, uncorrected and corrected visual acuity, and SE were not statistically significant between subgroups of surgical methods within each myopia group (all P > 0.05). At 12 months, in the moderate myopia group, there was less increase in 6-mm zone total C-HOA, coma, and SA with SMILE compared to the other groups (all P < 0.05). In the high myopia group, there was greater increase in photopic total C-HOA and trefoil and less increase in mesopic SA with SMILE (all P < 0.05). Conclusion In correction of moderate myopia, SMILE is preferable to prevent dilated pupil visual problems. In high myopia correction, femto-LASIK and PRK is preferred for normal light activities and SMILE is recommended to avoid dilated pupil visual problems.

SMILE After DALK to Reduce Residual Refraction: Two-Year Results

“…HOAs, except trefoil, showed a non-signi cant increase in the current study. HOA changes had a similar trend to normal corneas undergoing SMILE (9). Two points should be kept in mind.…”

“…Since the epithelium remains intact in this method and a lenticule is extracted from the stroma without ap removal, it is preferred to PRK and LASIK in eyes with no history of ocular surgery. The safety and e cacy of this procedure have been con rmed as well (8,9). To the best of our knowledge, only one study reported the 6-month results of this procedure in post-PK patients (10).…”