Vol.29 No.1 Original Article PDF

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

Jose Ernesto G. Roces, MD, Irwin Y. Cua, MD, Mellanie M. Oro, OD, Jerome M. Sarmiento, MD, Winston L. Villar, MD, Ruben Lim Bon Siong, MD

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.

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.

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).

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.