Evaluation of corneal biomechanical changes in moderate myopia after different techniques of corneal refractive surgeries

Background The most prevalent refractive error, which accounts for between 15 and 49% of cases worldwide, is myopia. Refractive surgery can fix refractive problems and lessen reliance on glasses or contact lenses. Aim This study aims to assess corneal biomechanical alterations following photorefractive keratectomy (PRK) and femtosecond laser small incision lenticule extraction (F-SMILE) in moderate myopic patients using CORVIS-ST (CST). Patients and methods This prospective, comparative, nonrandomized study was conducted on 40 patients’ eyes. with moderate myopia in a private center from January 2020 to December 2020, these eyes were subdivided into two groups: (a) The first group included 20 eyes that will receive PRK (b) The second group included 20 eyes that will receive F-SMILE. All participants will undergo operative (History taking, and examinations), preoperative (PRK, and F-SMILE), and postoperative (medications and Follow-up examinations) evaluations. Results Significant differences existed among the two groups in postoperative follow-up after 1 month and 6 months regarding deformation amplitude, radius, corvis biomechanical index, and intraocular pressure corrected biomechanically but There were insignificant differences among the two groups in terms of SPA in the same periods postoperatively. Conclusion Laser refractive surgery has a major impact on corneal biomechanical properties, as evidenced by significant changes in Corvis ST ocular biomechanical measures following PRK and F-SMILE procedures in myopic patients. The alterations resulting from F-SMILE are more substantial compared with PRK.