Pain, wound healing and refractive comparison of mechanical and transepithelial debridement in photorefractive keratectomy for myopia: results of 1 year follow-up.

Abstract

To compare the efficacy, safety and postoperative pain of mechanical versus transepithelial photorefractive keratectomy (PRK) techniques. Cornea and refractive surgery subspecialty. Prospective clinical trial. This prospective comparative study included 84 eyes of 42 patients with myopia who received mechanical PRK (m-PRK) in 1 eye and transepithelial PRK (t-PRK) in the contralateral eye. The mean patient age was 28.5±6.3 years (range 20-46 years). Postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refractions, postoperative epithelial healing time, surgical time, postoperative pain rating and corneal haze were recorded. At week 1, statistically the UDVA was significantly better in the t-PRK eyes; however, at 3 months, similar refractive stability was achieved in both groups. The mean spherical equivalent (SE) decreased from -2.44±1.00D (m-PRK eyes) and -2.88±1.24D (t-PRK eyes) at baseline to -0.19±0.38D and -0.30±0.40D, respectively, after 1 year. Surgical time was 98.6±9.8s in m-PRK eyes and 58.0±6.4s in t-PRK eyes. On postoperative days 1 and 3, using the global assessment rating, 81% of mPRK eyes that had pain, reported more pain than that reported for the tPRK eyes. In addition, m-PRK treated eyes demonstrated higher mean pain scores based on the 11-point numerical rating scale and Visual Analogue Scale (VAS). The mean time to complete epithelial healing was 2.19±0.39 days (t-PRK) and 3.76±0.43 days (m-PRK). t-PRK for mild-to-moderate myopia was more comfortable than conventional m-PRK; patients had less pain, and faster healing time.