Corneal irregular astigmatism after laser in situ keratomileusis for myopia

Abstract

AIMS To quantitatively evaluate the changes in corneal irregular astigmatism after laser in situ keratomileusis (LASIK) in relation to the amount of laser ablation. METHODS In 189 eyes of 116 patients undergoing LASIK for myopia, corneal topography was obtained before and 1 month after surgery. Using Fourier harmonic analysis of the topography data, corneal irregular astigmatism (asymmetry and higher order irregularity) was calculated. RESULTS By surgery, asymmetry component significantly increased (p r_s=0.440, p r_s=0.137, p = 0.074). CONCLUSION LASIK significantly increases the asymmetry component of the cornea which is dependent on the amount of laser ablation.