title: Comparison of Forward Light Scatter Changes Between SMILE, Femtosecond Laser-assisted LASIK, and Epipolis LASIK: Results of a 1-Year Prospective Study.
abstract: OBJECTIVE
  To investigate the characteristics of forward light scatter changes after small incision lenticule extraction (SMILE) and to compare these changes with those after femtosecond laser-assisted LASIK (femto-LASIK) and epipolis LASIK (epi-LASIK).
  
  
  METHODS
  A total of 303 eyes (SMILE group = 118 eyes, femto-LASIK group = 90 eyes, epi-LASIK group = 95) of 157 patients were included in this study. Forward straylight was measured preoperatively and 1 month, 6 months, and 1 year postoperatively using a C-Quant straylight meter (Oculus Optikgeräte, Wetzlar, Germany).
  
  
  RESULTS
  A significant increase in straylight was found in the femto-LASIK group only at 1 month after the procedure (P = .002), whereas significant increases were found in the epi-LASIK group at 1 month, 6 months, and 1 year after the procedure (P < .001). There were no significant increases in the straylight values after SMILE (P = .310) compared with the preoperative values, although the straylight values were slightly increased at 1 month. Significant differences in the postoperative-preoperative straylight value (Δlog[s]) changes were found between the SMILE, femto-LASIK, and epi-LASIK groups over the follow-up period (P < .001 for all). The correlations between the ablation depth/central corneal thickness ratios and the straylight values were statistically significant in the femto-LASIK and epi-LASIK groups, whereas no significant correlation between the lenticule thickness/central corneal thickness ratios and the stray-light values was found in the SMILE group.
  
  
  CONCLUSIONS
  Forward straylight was slightly increased in the early stage after the femto-LASIK procedure and was significantly increased throughout the follow-up period after epi-LASIK surgery. The SMILE procedure appeared to have a smaller effect on forward light scatter within the 1-year follow-up period.
authors.forename: Lulu
authors.initials: L
authors.lastname: Xu
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Yangchen
authors.initials: Y
authors.lastname: Liu
authors.forename: Wenjing
authors.initials: W
authors.lastname: Wu
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: Yanan
authors.initials: Y
authors.lastname: Wu
authors.forename: Gauhar Ali
authors.initials: GA
authors.lastname: Khan
mesh_terms: D000328:Adult; D001251:Astigmatism / Q000601:surgery*; D003319:Corneal Stroma / Q000601:surgery*; D048988:Corneal Surgery, Laser / Q000379:methods; D005260:Female; D019466:Glare; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008027:Light; D008297:Male; D009216:Myopia / Q000601:surgery*; D010783:Photometry; D011446:Prospective Studies; D012542:Scattering, Radiation; D014786:Vision Disorders / Q000175:diagnosis*; D055815:Young Adult