INTRODUCTION
Photorefractive keratectomy (PRK) has commonly been used in refractive surgeries. It is definitely a safe and effective technique for correction of low to moderate myopia and astigmatism. PRK involves removal of the epithelium of the cornea then ablation of the stroma. Epithelial debridement could be done by several techniques which includes rotating brush, chemical, mechanical, or with the help of excimer laser. An excimer laser is used in transepithelial PRK instead of chemical or mechanical debridement techniqes to ablate both the corneal epithelium and stroma. It has the potential to avoid debridement- and corneal flap-related Problems in traditional PRK and laser in situ keratomileusis (LASIK) procedures, respectively. StreamLight™ is a new transepithelial PRK procedure in which removal of the epithelium occur first by Phototherapeutic keratectomy (PTK) and after that PRK take place in a single procedure.
The size and position of the PTK treatment zone are automatically aligned with the PRK ablation profile thanks to newly calculated nomograms and centration is only required once in the StreamLight™ surgery. Additionally, a multidimensional eye tracker is used throughout the surgery.
AIM OF THE WORK
The aim of this study is to compare safety, efficacy and predictability of PRKusing manual epithelial removal method versus transepithelial PRK.