Corneal irregular astigmatism after hyperopic laser in situ keratomileusis

Cornea. 2005 Oct;24(7):789-92. doi: 10.1097/01.ico.0000159753.98111.16.

Abstract

Purpose: To evaluate the changes in irregular astigmatism after hyperopic laser in situ keratomileusis (LASIK).

Methods: In a prospective case series, 15 eyes of 12 patients who had hyperopic LASIK were evaluated. Corneal topography was obtained before and after hyperopic LASIK. Corneal irregular astigmatism (asymmetry and higher-order irregularity) was calculated using Fourier harmonic analysis of the topography data.

Results: Hyperopic LASIK significantly increased the asymmetry component at 3 (P = 0.0085) and 6 months (P = 0.0307) postoperatively. The mean higher-order irregularity was not significantly changed at any postoperative time-point (P = 0.222). The achieved change in the spherical equivalent was significantly correlated with the post/preoperative ratio of asymmetry (R = 0.695, P = 0.0030).

Conclusion: Hyperopic LASIK significantly increases the asymmetry component of the cornea, which is correlated with the achieved change in the spherical equivalent.

MeSH terms

  • Adult
  • Astigmatism / diagnosis
  • Astigmatism / etiology*
  • Cornea / pathology
  • Cornea / surgery
  • Corneal Diseases / diagnosis
  • Corneal Diseases / etiology*
  • Corneal Topography
  • Female
  • Fourier Analysis
  • Humans
  • Hyperopia / surgery*
  • Keratomileusis, Laser In Situ / adverse effects*
  • Male
  • Middle Aged
  • Prospective Studies