The Influence of the Epithelium Removal Method on the Outcomes of Photorefractive Keratectomy

To compare the outcomes and complications reported for alternative methods of removal of the corneal epithelium during photorefractive keratectomy (PRK).

Literature review.

Excimer laser-based refractive surgery treatments are safe and effective, and PRK is one of the most common methods used to treat refractive errors. Conventional PRK methods involve removing the corneal epithelium overlying the intended stromal ablation with mechanical debridement, dilute ethanol exposure, or a rotating brush, and each method is associated with potential complications. An alternative method in which the corneal epithelium overlying the intended stromal ablation is removed with the excimer laser followed by refractive stromal ablation (a single-step, "no-touch" method) termed transepithelial PRK (transPRK) continues to evolve and has advantages and disadvantages compared to the other methods.

Mechanical blade scrape PRK and alcohol-assisted PRK techniques have been most used and yield excellent results. However, alcohol-assisted epithelial removal triggers increased keratocyte death at the time of surgery that is hypothesized to underlie the development of breakthrough haze after PRK with mitomycin C. TransPRK continues to have limitations but as the technique evolves it appears to potentially be a more precise method. [.