Longitudinal Comparison of Outcomes After Sub-Bowman Keratomileusis and Laser in Situ Keratomileusis: Randomized, Double-Masked Study

PURPOSE: To compare the outcomes of sub-Bowman keratomileusis (100-mu m flap) and laser in situ keratomileusis (LASIK) (120-mu m flap) using 150-kHz ferrito-second laser. DESIGN: Randomized, double-masked, contralateral clinical trial. METHODS: One hundred patients (200 eyes) with myopia or myopic astigmatism were included. Postoperative examinations were performed at week 1 and months 1, 3, 6, and 12. Main outcome measures included postoperative uncorrected (UCVA) and best-corrected distance visual acuity (BCVA); manifest refraction spherical equivalent; efficacy and safety indices; corneal thickness; and complications. RESULTS: The mean age of patients was 33.9 +/- 7.9 years. Overall, the preoperative UCVA, BCVA, and manifest refraction spherical equivalent were 1.349 +/- 0.332, -0.022 +/- 0.033, and -5.81 +/- 1.61 diopters, respectively. No significant difference was observed in preoperative (P >= .226) or intraoperative parameters (P >= .452) between both groups, except residual stromal thickness (P < .001). The UCVA, manifest refraction spherical equivalent, and central corneal thickness stabilized by 1 week, while the thinnest corneal thickness stabilized by 3 months postoperatively. There was no significant difference between both groups for any parameter during all follow-up visits (P >= .132) except the 3-month safety index, which was better in the sub-Bowman keratomileusis group (P = .007). Soft opaque bubble layer was noted intraoperatively in 12 cases (7, 100-mu m group; 5, 120-mu m group; P =.577). No postoperative complications were observed. CONCLUSIONS: Our study did not find any differences in the visual and refractive outcomes between femtosecond-assisted sub-Bowman keratomileusis and LASIK. Both surgeries resulted in quick, visual recovery as early as 1 week postoperatively. (C) 2015 by Elsevier Inc. All rights reserved.