IRCT20180428039441N1 IRCT 2018-08-27 Noor Eye hospital Steroid after PRK - Short versus long term topical steroid effect on corneal haze incidence after photorefractive keratectomy with mitomycin-C 2018-09-23 anticipated 222 Complete https://irct.ir/trial/31800 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Prevention, Other design features: -, Randomization description: Randomization will be done using permuted-block randomization method. In addition to balancing the number of people between the three groups, this method It can prevent the prediction of intervention sequence. Blocks random sequence will be provided by STATA software. In order to maintenance of allocation concealment, full report will be published after completion of the study, Blinding description: Patients will be unaware of which group (intervention or placebo) they are in. Also, those who perform the tests (optometrists and the clinical ophthalmologist responsible for corneal opacity diagnosis) will also be unaware of which group (intervention or placebo) is evaluating. 3 Corneal haze after photorefractive keratectomy. Intervention 1: 1. Control group: Participants who will receive topical steroid after PRK for 3 months. A one week of Betamethasone 0.1% and 11 weeks of tapering Fluorometholone 0.1% (FML). Intervention 2: 2. Intervention group: Participants who will receive topical steroid after PRK for 2 months. A one week of Betamethasone 0.1% and 7 weeks of tapering Fluorometholone 0.1% (FML). Intervention 3: 3. Intervention group: Participants who will receive topical steroid after PRK for 1 months. A one week of Betamethasone 0.1% and 3 weeks of tapering Fluorometholone 0.1% (FML). No - There is not a plan to make this available Justification or reason for not sharing IPD is Per request, we will decide about the dissemination of the data.