Safety and Effectiveness of Thin-flap LASIK Using a Femtosecond Laser and Microkeratome in the Correction of High Myopia in Chinese Patients

PURPOSE: To establish safety and effectiveness of thin-flap LASIK using a femtosecond laser and microkeratome in correcting high myopia in Chinese patients. METHODS: Two hundred seventy-four eyes of 148 Chinese patients with high myopia whose spherical equivalent refraction (SE) ranged from -6.12 to -15.75 diopters (D) received thin-flap LASIK with the VISX S4 IR excimer laser system. Corneal flaps were created with a femtosecond laser (15-kHz Intralase, 134 eyes of 76 patients, target flap thickness 100 mu m) and Moria M2 microkeratome (90-mu m head, 140 eyes of 72 patients, target flap thickness 110 mu m). Clinical outcomes were assessed with uncorrected (UCVA) and best spectacle-corrected visual acuity (BSCVA), manifest refraction, wavefront aberrometry, Schirmer tests, and tear break-up time (TBUT) at 1 day, 1 week, and 1 and 3 months postoperatively. RESULTS: At 3 months, both groups showed comparable clinical outcomes in most parameters assessed, including the percent of postoperative UCVA better than or equal to preoperative BSCVA (P=.642), mean residual spherical equivalent refraction (P=.448), mean Schirmer test (P=.950), and mean TBUT (P=.867). Postoperative coma, trefoil, and spherical aberration were similar in both groups (P=.202, P=.898, and P=.890, respectively). Both groups had a similar percent of eyes with a change of SE of <1.00 D (P=.284). CONCLUSIONS: Thin-flap LASIK with a femtosecond laser and microkeratome are both safe and effective for the correction of high myopia in Chinese patients. Femtosecond laser shows similar predictability, stability, and induction of higher order aberrations to the microkeratome. [J Refract Surg. 2010;26:99-106.] doi:10.3928/1081597X-20100121-05