Transepithelial photorefractive keratectomy to treat mild myopia.

PURPOSE

To assess the safety and effectiveness of transepithelial photorefractive keratectomy (T-PRK) in patients with mild myopia using the Schwind Amaris 750 s Excimer laser system which take corneal epithelium variability in consideration during ablation.

METHODS

A prospective case series study of patients with mild myopia with or without astigmatism (spherical equivalent ≤ -3 diopters), who underwent T-PRK as a single-step treatment, was carried out at King Abdulaziz University Hospital, Riyadh between May 2017 and January 2018. The main outcomes included postoperative uncorrected distance visual acuity (UDVA), residual refraction (manifest refraction) and complications.

RESULTS

A total of 42 patients (84 eyes) underwent bilateral T-PRK with a preoperative spherical equivalent ranging from - 0.75 to - 3.00 D. Median spherical equivalent before Trans-PRK was - 1.75 (- 1.25to - 1.75). The spherical equivalent six months after Trans-PRK was 0.0 (- 0.25 to 0.5). All patients had a postoperative UDVA of 20/20 or better in the last follow-up. Transient postoperative corneal haze was observed in five eyes (6%).

CONCLUSION

T-PRK appears to be safe and effective in patients who have mild myopia, with or without astigmatism. The normal variation in corneal epithelial thickness seems not to affect the outcomes.