Effect of Preoperative Keratometric Power on Intraoperative Complications in LASIK in 34,099 Eyes

Abstract

To evaluate the effect of preoperative keratometric power on the intraoperative complications in LASIK for myopia, hyperopia, and astigmatism. In this retrospective study, the records of 34,099 eyes of 17,388 patients who underwent LASIK for myopia, hyperopia, and astigmatism using the Moria LSK One manual microkeratome and the Bausch & Lomb Technolas 217 Z excimer laser were reviewed. One thousand three hundred thirty-eight (3.92%) intraoperative microkeratome complications were identified in the total number of eyes: 571 (1.67%) free caps, 320 (0.93%) epithelial abrasions, 282 (0.82%) thin/irregular flaps, 126 (0.36%) incomplete flaps, and 39 (0.11%) flap buttonholes. When eyes were stratified according to preoperative keratometric power, eyes with flatter corneas usually had more free caps and incomplete flaps than eyes with steeper corneas (P < .05), whereas eyes with steeper corneas usually had more epithelial abrasions and thin/irregular flaps than eyes with flatter corneas (P < .05). The risk of free caps, incomplete flaps, and epithelial abrasions was greater when bigger keratome rings (H) were used than when smaller rings (-1) were used (P < .05). The incidence of buttonholes was independent of the preoperative keratometric power, keratome plate (100 or 130 microm), and keratome ring (-1, -2, or H). No statistically significant relationship was found between preoperative keratometric power and incidence of flap buttonholes in this series. Eyes with flatter corneas tended to have more free caps and incomplete flaps, whereas eyes with steeper corneas tended to have more epithelial abrasions and thin/irregular flaps.