Excimer laser correction of moderate to high astigmatism with a non-wavefront-guided aberration-free ablation profile: Six-month results

J Cataract Refract Surg. 2009 Oct;35(10):1789-98. doi: 10.1016/j.jcrs.2009.05.035.

Abstract

Purpose: To evaluate the postoperative clinical outcomes and higher-order aberrations (HOAs) in eyes with astigmatism greater than 2.00 diopters (D) that had laser in situ keratomileusis (LASIK) using a non-wavefront-guided aberration-free ablation profile.

Settings: Private practice.

Methods: This retrospective study evaluated the 6-month results of LASIK for astigmatism greater than 2.00 D. Standard examinations and preoperative and postoperative wavefront analyses were performed. Aspheric treatments with a non-wavefront-guided ablation profile were planned using software integrated into the Amaris flying-spot excimer laser system, which was used to perform the ablations. The LASIK flaps were created using an LDV femtosecond laser. Clinical outcomes were predictability, refractive outcomes, safety, efficacy, and wavefront aberration.

Results: At 6 months, 84% of the 50 eyes evaluated achieved 20/20 or better uncorrected distance visual acuity (UDVA) and 40% achieved 20/16 or better UDVA. Forty-four percent of eyes were within +/-0.25 D of the attempted astigmatic correction, and 78% were within +/-0.50 D. The mean SE was -0.12 D +/- 0.25 (SD) and the mean astigmatism, 0.50 +/- 0.26 D. Corrected distance visual acuity (CDVA) improved in 36% of eyes; 4% of eyes lost 1 line of CDVA. The predictability slope for astigmatism was 0.97 and the intercept, -0.15 D. There were no clinically relevant changes in any aberration metric from preoperatively to postoperatively.

Conclusions: Excimer laser LASIK using a non-wavefront-guided aberration-free ablation profile yielded excellent visual outcomes. The preoperative astigmatism was reduced to subclinical values with no clinically relevant induction of HOA.

MeSH terms

  • Astigmatism / physiopathology
  • Astigmatism / surgery*
  • Corneal Topography
  • Humans
  • Keratomileusis, Laser In Situ / methods*
  • Lasers, Excimer / therapeutic use*
  • Refraction, Ocular / physiology
  • Retrospective Studies
  • Treatment Outcome
  • Visual Acuity / physiology