Comparison of higher-order aberrations Wavefront-guided versus standard laser in situ keratomileusis in low to moderate myopia

Abstract

Objective: To compare the pre- and postoperative changes in higher-order aberrations after standard LASIK (PlanoScan, Bausch & Lomb) and wavefront-guided LASIK (Zyoptix, Bausch & Lomb) and determine their effects on visual acuity, contrast sensitivity, and refractive outcomes at one year postoperatively.

Methods: In a prospective, randomized clinical trial, 15 patients with low to moderate myopia had standard LASIK on one eye and wavefront-guided LASIK on the contralateral eye. A Hartmann-Shack aberrometer (Zywave, Bausch & Lomb) was used to measure the aberrations. Root-mean-square (RMS) values were determined. Uncorrected visual acquity (UCVA), best corrected visual acuity (BCVA), refractive errors, and contrast sensitivity were also measured.

Results: Thirteen (87%) of the 15 eyes treated with Zyoptix and 12 (80%) of the 15 treated with PlanoScan had UCVA of 20/20 at one year postoperatively. The mean difference in the pre- and postoperative contrast sensitivity showed no significant changes in all spatial frequencies in both groups (p > 0.05). The difference in attempted versus achieved refraction was not significant between the two groups (p = 0.794). In all eyes, the total RMS increased postoperatively (p < 0.001), but the mean RMS difference from the preoperative values between the two groups was not statistically significant (p = 0.257).

Conclusion: LASIK in low to moderate myopia increases overall high-order aberrations. Zyoptix LASIK offers no advantage over PlanoScan LASIK in decreasing highorder aberrations postoperatively and in achieving better visual and refractive outcomes.