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Purpose: To compare refractive outcomes, contrast sensitivity, higher-order aberrations (HOAs), and patient satisfaction after photorefractive keratectomy for correction of moderate myopia with two methods: tissue saving versus wavefront optimized., Methods: In this prospective, comparative study, 152 eyes (80 patients) with moderate myopia with and without astigmatism were randomly divided into two groups: the tissue-saving group (Technolas 217z Zyoptix laser; Bausch & Lomb, Rochester, NY) (76 eyes of 39 patients) or the wavefront-optimized group (WaveLight Allegretto Wave Eye-Q laser; Alcon Laboratories, Inc., Fort Worth, TX) (76 eyes of 41 patients). Preoperative and 3-month postoperative refractive outcomes, contrast sensitivity, HOAs, and patient satisfaction were compared between the two groups., Results: The mean spherical equivalent was -4.50 ± 1.02 diopters. No statistically significant differences were detected between the groups in terms of uncorrected and corrected distance visual acuity and spherical equivalent preoperatively and 3 months postoperatively. No statistically significant differences were seen in the amount of preoperative to postoperative contrast sensitivity changes between the two groups in photopic and mesopic conditions. HOAs and Q factor increased in both groups postoperatively (P = .001), with the tissue-saving method causing more increases in HOAs (P = .007) and Q factor (P = .039). Patient satisfaction was comparable between both groups., Conclusions: Both platforms were effective in correcting moderate myopia with or without astigmatism. No difference in refractive outcome, contrast sensitivity changes, and patient satisfaction between the groups was observed. Postoperatively, the tissue-saving method caused a higher increase in HOAs and Q factor compared to the wavefront-optimized method, which could be due to larger optical zone sizes in the tissue-saving group., (Copyright 2015, SLACK Incorporated.)

Purpose: To compare corneal stromal and endothelial cells after photorefractive keratectomy with intraoperative mitomycin C in alcohol-assisted versus mechanical epithelial debridement using confocal microscopy., Methods: This prospective randomized comparative study was performed on 88 eyes (44 patients) with myopia up to -6.00 diopters. The right eye of each patient was randomly assigned to either mechanical or alcohol-assisted groups, and the left eye was assigned to the alternate group. Confocal microscopy was performed preoperatively and at 3 months postoperatively. The main outcome measures were epithelial thickness; number of keratocytes in the anterior, mid-, and posterior stroma; and characteristics of the central corneal endothelial cells in terms of density, mean cell area, and polymegathism and hexagonality., Results: Three months after surgery, no statistically significant difference was noted between the study groups in terms of epithelial thickness. We also found no statistically significant difference in central corneal endothelial cells regarding cell density, mean cell area, hexagonality, or polymegathism. Compared with baseline values, the density of mid- and posterior stromal keratocytes showed no significant change in either group, whereas it decreased significantly in the anterior stroma in both groups 3 months after surgery., Conclusions: We found that the adverse effects of photorefractive keratectomy with mitomycin C on central corneal endothelial cells were comparable between the mechanical and alcohol-assisted epithelial debridement groups and the significant decrease in postoperative keratocyte density in anterior stroma was comparable between the two groups. The choice of their application could be left to the discretion of the ophthalmologist.

Purpose: To compare visual outcomes and contrast sensitivity after wavefront-optimized or conventional photorefractive keratectomy (PRK) in myopic patients with or without astigmatism., Setting: Vanak Eye Surgery Center, Tehran, Iran., Design: Comparative case series., Methods: Patients with low to moderate myopia with or without astigmatism were allocated into 2 groups. The study group was treated with wavefront-optimized PRK (Allegretto Wave Eye-Q software version 2.020 default treatment) and the control group, with conventional PRK (Technolas 217z). In all cases, treatments were bilateral and performed with the same device. Baseline and 3-month postoperative measures were uncorrected and corrected distance visual acuities, manifest refraction, and contrast sensitivity., Results: Each group comprised 66 eyes. The mean preoperative spherical equivalent refraction improved from -2.99 diopters (D) ± 1.02 (SD) preoperatively to -0.08 ± 0.26 D 3 months postoperatively in the study group and from -2.66 ± 0.95 D to 0.01 ± 0.30 D, respectively, in the control group. In both groups, the postoperative mesopic and photopic contrast sensitivity decreased significantly at most spatial frequencies. The postoperative decrease in contrast sensitivity in both groups was comparable except at spatial frequencies of 3 cycles per degree (cpd) under mesopic conditions and 12 cpd under photopic conditions, frequencies at which the control group had a greater reduction., Conclusions: Visual acuity and refractive error outcomes were similar in both treatment groups. After 3 months, mesopic and photopic contrast sensitivity were significantly decreased in both groups; the reduction in the 2 groups was almost comparable., Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned., (Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)