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Published on: November 12, 2015
Clinical outcomes of conventional Vs. transepithelial photorefractive keratectomy: A prospective contralateral eye
M Basil Marchi1, Adeya Al Harami1, Ahmed Maher2
1Department of Ophthalmology, Hamad Medical Corporation, Doha, Qatar.
Abstract:
PurposeTo compare the clinical outcomes of conventional photorefractive keratectomy (PRK) and transepithelial PRK (TransPRK) for the correction of myopic refractive errors.MethodsThis prospective, paired-eye comparative study included 48 eyes of 24 patients. Each patient underwent conventional PRK in the right eye and TransPRK in the left eye. Both patient and outcome assessors were blinded to treatment allocation. Preoperative and postoperative parameters including uncorrected distance visual acuity (UDVA), spherical equivalent (SE), postoperative pain, epithelial healing time, and complications were evaluated. Paired statistical analyses were used to compare outcomes between the two procedures.ResultsThere were no significant differences in baseline characteristics between the groups. Postoperatively, there were no statistically significant differences in UDVA (p = 0.084) or final SE (p = 0.512). Epithelial healing was faster in the TransPRK group but failed to show statistical significance (p = 0.371). However, postoperative pain was significantly higher in the TransPRK group, with a median pain score of 8 (IQR 8-10) compared to 6 (IQR 6-8) in the PRK group (p = 0.014). Clinically significant postoperative haze was observed in 3 (12.5%) of patients, with an identical pattern in both eyes of every affected patient.ConclusionBoth conventional PRK and TransPRK are safe and effective procedures for myopic correction, providing comparable visual and refractive outcomes. In this cohort, TransPRK was associated with significantly greater early postoperative pain, a finding that contrasts with much of the existing literature and warrants further investigation. The contralateral study design highlights the consistency of other outcomes while isolating this key difference.