Purpose: To assess the efficacy, predictability, safety, and quality-of-life effects of topography-guided laser in situ keratomileusis (LASIK) for the correction of myopia with astigmatism using the EC-5000 CXII excimer laser equipped with a customized aspheric treatment zone algorithm.
Setting: Ophthalmology clinics in the United States and Mexico.
Methods: In a multicenter United States Food and Drug Administration study of topography-guided LASIK, 4 centers enrolled 135 eyes with a spherical manifest refraction error ranging from -0.50 to -7.00 diopters (D) and astigmatism ranging from 0.50 to 4.00 D. All eyes were targeted for emmetropia. Refractive outcomes, higher-order aberrations (HOAs), and contrast sensitivity were analyzed preoperatively and postoperatively. Patient satisfaction was assessed using 2 questionnaires.
Results: Six months postoperatively, the mean manifest refraction spherical equivalent in all eyes was -0.09 D +/- 0.31 (SD); of the 131 eyes, 116 (88.55%) had an uncorrected visual acuity of 20/20 or better and 122 (93.13%) had an MRSE within +/-0.50 D. The best spectacle-corrected visual acuity (BSCVA) increased by 2 or more lines in 21 (16.03%) of 131 eyes; no eye lost 2 lines or more of BSCVA. The total ocular HOA increased by 0.04 microm. Patients reported significantly fewer night driving and glare/halo symptoms postoperatively than preoperatively.
Conclusion: Use of a customized aspherical treatment zone in eyes with myopia and astigmatism was safe, effective, and predictable and reduced symptoms associated with night driving, glare, and halos.