To investigate the effect of surface fluid on the ablation rate and efficacy of 213-nm solid-state laser during photorefractive keratectomy (PRK).

Twelve rabbits (24 eyes) underwent myopic PRK for the correction of 10 diopters using 213-nm solid-state laser. Photoablation was performed with removal of corneal surface fluid using the Weckcel® sponge every 5 seconds in one eye and without removal of corneal surface fluid in the control eye. The mean central corneal thickness (CCT) was evaluated preoperatively, and at 1 week, 4 weeks postoperatively.

The mean CCT of group 1 (with removal of corneal surface fluid) were 361.3±13.9 µm preoperatively and 321.4±18.5 µm at 4 weeks postoperatively. The mean CCT of group 2 (without removal of surface fluid) were 358.7±8.9 µm preoperatively and 338.4±12.0 µm at 4 weeks postoperatively. The mean ablation depths were 39.8±7.4 µm in group 1 and 20.3±5.8 µm in group 2 at 4 weeks postoperatively p <0.05).

Induced corneal surface fluid during PRK may influence the ablation efficacy and accuracy of solid-state laser. This result should be considered in clinical trialswith 213-nm solid-state laser, especially in high myopes.