Excimer Laser Photorefractive Keratectomy with a Rotary Epithelial Scrubber and Post-laser Corneal Chilling

ABSTRACT

PURPOSE: To evaluate the effect of rotary epithelial scrubber and post-laser corneal chilling on clinical outcomes of excimer laser PRK (VISX 20/20B VisionKeyTM) METHODS: PRK with a rotary epithelial scrubber and post-laser chilled BSS irrigation was performed in 231 eyes of 141 patients (Group I: -4.33+/-0.98 D, July 1997~July 1999). Conventional PRK with mechanical epithelial removal was performed in 282 eyes of 181 patients (Group II: -4.33+/-0.99 D, September 1994~April 1997). A retrospective clinical data of two different PRK procedures was compared. RESULTS: Mean epithelial removal time was significantly short in group I (8.6+/-3.4 sec) than in group II (29.8+/-12.8 sec) (p<0.05). More rapid epithelial healing was achieved in group I (2.6+/-0.7 days) than in group II (2.8+/-0.7 days) (p<0.05). At 12 months, UCVA was 0.7 or better in 99.4% (162/163 eyes) of group I and 92.8% (77/88 eyes) of group II (p<0.05). At 12 months, 98.8% (161/163 eyes) in group I and 95.2% (79/83 eyes) in group II were within +/-1.0 D of emmetropia (p<0.05). After 2 years follow-up, there were no cases showing corneal haze worse than grade 1 in group I. CONCLUSIONS: Excimer laser PRK after precise removal of the epithelium with a rotary scrubber and post-laser corneal chilling provided more rapid epithelialization and visual recovery than conventional PRK. There was statistically significant improvement in clinical outcomes and occurrence of corneal haze in group I comparing with group II. We think that this excimer laser PRK technique be more ideal for the correction of mild to moderate myopia to avoid the serious flap complication of LASIK.