title: Wavefront-guided versus wavefront-optimized laser in situ keratomileusis: contralateral comparative study.
abstract: OBJECTIVE
  To compare the outcomes of wavefront-guided and wavefront-optimized treatment in fellow eyes of patients having laser in situ keratomileusis (LASIK) for myopia.
  
  
  METHODS
  Medical and Vision Research Foundation, Tamil Nadu, India.
  
  
  METHODS
  This prospective comparative study comprised 27 patients who had wavefront-guided LASIK in 1 eye and wavefront-optimized LASIK in the fellow eye. The Hansatome (Bausch & Lomb) was used to create a superior-hinged flap and the Allegretto laser (WaveLight Laser Technologie AG), for photoablation. The Allegretto wave analyzer was used to measure ocular wavefront aberrations and the Functional Acuity Contrast Test chart, to measure contrast sensitivity before and 1 month after LASIK. The refractive and visual outcomes and the changes in aberrations and contrast sensitivity were compared between the 2 treatment modalities.
  
  
  RESULTS
  One month postoperatively, 92% of eyes in the wavefront-guided group and 85% in the wavefront-optimized group had uncorrected visual acuity of 20/20 or better; 93% and 89%, respectively, had a postoperative spherical equivalent refraction of +/-0.50 diopter. The differences between groups were not statistically significant. Wavefront-guided LASIK induced less change in 18 of 22 higher-order Zernike terms than wavefront-optimized LASIK, with the change in positive spherical aberration the only statistically significant one (P= .01). Contrast sensitivity improved at the low and middle spatial frequencies (not statistically significant) and worsened significantly at high spatial frequencies after wavefront-guided LASIK; there was a statistically significant worsening at all spatial frequencies after wavefront-optimized LASIK.
  
  
  CONCLUSIONS
  Although both wavefront-guided and wavefront-optimized LASIK gave excellent refractive correction results, the former induced less higher-order aberrations and was associated with better contrast sensitivity.
authors.affiliation: Medical and Vision Research Foundation, Tamil Nadu, India. drpp@snmail.org
authors.forename: Prema
authors.initials: P
authors.lastname: Padmanabhan
authors.forename: Michael
authors.initials: M
authors.lastname: Mrochen
authors.forename: Subam
authors.initials: S
authors.lastname: Basuthkar
authors.forename: Deepa
authors.initials: D
authors.lastname: Viswanathan
authors.forename: Roy
authors.initials: R
authors.lastname: Joseph
mesh_terms: D000293:Adolescent; D000328:Adult; D015350:Contrast Sensitivity / Q000502:physiology; D003319:Corneal Stroma / Q000601:surgery*; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000295:instrumentation / Q000379:methods*; D008297:Male; D009216:Myopia / Q000601:surgery*; D011446:Prospective Studies; D013524:Surgical Flaps; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology