Comparison of conventional and transepithelial methods of epithelial debridement in photorefractive keratectomy in terms of postoperative recovery rate
Randomized clinical trial, 2 parallel and double-blinded groups
Settings and conduct:
Patients with myopia and myopia astigmatism candidates for PRK using the Amaris eximer laser at Noor eye Hospital will be randomly assigned to one of two intervention groups using a randomization blocks table. Epithelial defect imaging will be performed on the day of surgery immediately following the surgery, and on consecutive days after surgery until wound healing. Epithelial defect area in each image will be calculated using an image processing software. Also, on postoperative day 1, 3 and 7, a standardized questionnaire will be used to assess pain severity and symptoms in each eye. Three months later, the patient is examined for visual acuity, refraction, and haze.
Participants/Inclusion and exclusion criteria:
Inclusion criteria are: age between 18 to 50 years; equivalent sphere at least -2.00 diopter with astigmatism up to -4.00 diopter and myopia up to -8.00 diopter; stability of refraction for at least one year before surgery;
corrected visual acuity more than 20/30.
Contact lens use should be discontinued at least 3 weeks prior to surgery.
Exclusion criteria include any eye pathology including corneal dystrophy, keratoconus or keratoconus suspect, glaucoma or glaucoma suspect; and a history of diabetes, autoimmune diseases and any previous ophthalmic surgery.
Group 1: One eye is operated by Trans PRK and the other one by Mechanical PRK
Group 2: One eye is operated by Trans PRK and the other by Alcohol-assisted PRK
Main outcome variables:
The healing rate of corneal epithelial defect