The Effect of Photorefractive Keratectomy with Technolas 217z and Lasersight LSX Excimer Laser Systems on the Refractive Errors Correction

To evaluate refractive, visual, topographic, and wavefront outcome of photorefractive keratectomy (PRK) for treatment of myopia and myopic astigmatism with two different excimer laser systems: Technolas 217z and Lasersight LSX excimer lasers.

183 eyes of 95 patients enrolled in this clinical trial. Patients underwent PRK in a Sadra refractive surgery center with Technolas or Lasersight system by a single surgeon between 2007 and 2011. For PRK we used Technolas 217z in one group and Lasersight LSX excimer laser in another group. Subjects examined before and 24 months after surgery evaluating vision, refraction, Orbscan topography, and Wavefront analysis. Data collected, analyzed with SPSS 16. We used Student t-test for statistical data analysis.

83 eyes were in the Lasersight group and 100 eyes in the Technolas group. Pre-op spherical equivalent refraction was not different in two groops. After surgery it was -0.93 ± 0.73 in Technolas and -0.19 ± 0.40 in Lasersight group, the difference was statistically significant (P < 0.001). Post-op difference vector of astigmatic correction was 0.44 ± 0.58 in Technolas and 0.41 ± 0.26 diopters in Lasersight group (P = 0.04). Post-op LogMAR Acuity was 0.015 ± 0.027 in Technolas and 0.0005 ± 0.005 in Lasersight group (P < 0.001). Post-op Q value of asphericity was 0.24 ± 0.33 in Technolas and 0.46 ± 0.37 in Lasersight group (P < 0.001).

Post-op spherical equivalent refractive outcome, best corrected distance visual acuity and satisfaction were better in Lasersight group. We did not find any difference regarding post-op wavefront analysis between groups.