The 18-Month Outcomes of a Contralateral, Randomized, Prospective Clinical Trial Comparing Photorefractive Keratectomy and SMILE for Myopia

Abstract

Purpose: To compare clinical outcomes and patient satisfaction of photorefractive keratectomy (PRK) and small incision lenticule extraction (SMILE) for myopia. Methods: This contralateral, randomized, prospective clinical trial included 86 eyes of 43 patients diagnosed as having spherical equivalent (SE) from −1.00 to −8.00 diopters (D). One eye of each patient was randomly allocated to receive either PRK with 0.02% mitomycin C or SMILE. Visual acuity measurement, slit-lamp microscopy, manifest and cycloplegic refraction, Scheimpflug corneal tomography, contrast sensitivity assessment, ocular wavefront aberrometry, and a satisfaction questionnaire were performed preoperatively and during an 18-month follow-up. Results: Forty-three eyes of each group completed the study. After 18 months of follow-up, eyes treated with PRK and SMILE showed comparable results regarding uncorrected distance visual acuity (−0.12 ± 0.07 and −0.25 ± 0.09, respectively), safety, efficacy, contrast sensitivity, and ocular wavefront aberrometry. For predictability, eyes treated with PRK had a statistically lower residual spherical equivalent when compared with eyes treated with SMILE. Residual astigmatism of 0.50 D or less was achieved in 95% of the PRK group and 81% of the SMILE group. At the 1-month follow-up visit, the PRK group presented worse evaluation in relation to vision and foreign body sensation when compared to the SMILE group. Conclusions: Both PRK and SMILE presented as safe and effective strategies for treating myopia with comparative clinical results. Eyes treated with PRK showed lower spherical equivalent and residual astigmatism. In the first month, eyes treated with SMILE showed less foreign body sensation and faster visual recovery. [ J Refract Surg . 2023;39(3):180–186.]