Abstract
To evaluate the effect of preoperative keratometry on visual and refractive outcomes after Myopic LASER in Situ Keratomileusis (LASIK) in eyes with preoperative spherical equivalent (SE) of -6.00D or less. Material and Methods: A retrospective study enrolling clinical records of 482 eyes of 275 patients with myopia who underwent LASIK between 2009 and 2016. Subjects were grouped according to the degree of preoperative mean keratometry (Km), into three groups: Group 1 (Flat Cornea): Km ≤ 42.00 diopters (D); Group 2: 42.00 46.00D; Group 3 (Steep Cornea): Km ≥ 46.00D. To evaluate the prognostic impact of keratometry in Myopic LASIK, we considered the results measured at 6 months postoperatively, including uncorrected distance visual acuity (UDVA), postoperative sphere, cylinder, SE and its variation. Results: The mean preoperative SE was -3.91 ± 1.54D, ranging between -0.88 and -6.00D. The percentage of eyes achieving a postoperative SE of ±0.50D was 39.5%, 31.8% and 26% in groups 1, 2 and 3 respectively. Moreover, in group 3, 14.3% of the eyes had a residual SE of -2.00D or greater, contrasting with the groups 1 and 2 with only 6% - 7%. These results were found to be statistically significant. Concerning UDVA, eyes achieving 20/25 or more were 81.5%, 81.8% and 71.5%, and 20/50 or less were 6.7%, 6.2% and 11.7% in groups 1, 2 and 3 respectively. Conclusions: Myopic eyes with steeper corneas seem to have greater tendency to undercorrection, also presenting worse visual outcomes.
Highlights
Laser in situ keratomileuis (LASIK) is, nowadays, the most commonly performed keratorefractive surgery, with well-established surgical indications, with numerous studies validating its long-term efficacy and safety [1]
The purpose of our study is to evaluate the effect of preoperative mean keratometry on refractive and visual outcomes of LASER in Situ Keratomileusis (LASIK) in myopic eyes with preoperative spherical equivalent (SE) of −6.00 or less
In order to evaluate the prognostic impact of keratometry in myopic LASIK, we considered the results measured at 6 months postoperatively, including uncorrected distance visual acuity in ETDRS grading system (UDVA), sphere, cylinder, SE and its variation
Summary
Laser in situ keratomileuis (LASIK) is, nowadays, the most commonly performed keratorefractive surgery, with well-established surgical indications, with numerous studies validating its long-term efficacy and safety [1]. LASIK is based on the modification of corneal curvature, inducing biomechanical changes with the purpose of altering refractive power [2]. Myopia and myopic astigmatism are corrected by the flattening of its central anterior surface, so that the increase of corneal radius will lower dioptric power with the objective of emmetropization [3]. For this reason, keratometry is a potential prognostic factor, which could in part explain cases of residual postoperative refractive error or unsatisfactory visual outcome. Studies reported a trend toward undercorrection in flat corneas in eyes with high myopia, whereas, studies analyzing moderate myopia reported better refractive and visual outcomes in such corneas with lower mean keratometry
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
