The photorefractive keratectomy was the first correction mode refractive laser. It's a
photo-ablation of a predetermined thickness of anterior corneal stroma. Debridement of
epithelium can be done either mechanically (m-PRK) or by laser (trans-PRK). Trans-PRK has a
lot of interests: facility and speed of procedure as well as suppression of human variable.
Very good results are obtained by m-PRK. The aim of this study is to show equivalence or non
inferiority of trans-PRK over conventional m-PRK in terms of safety and refractive efficiency