title: Intraocular straylight and contrast sensitivity after contralateral wavefront-guided LASIK and wavefront-guided PRK for myopia.
abstract: OBJECTIVE
  To compare intraocular straylight measurements and contrast sensitivity after wavefront-guided LASIK (WFG LASIK) in one eye and wavefront-guided photorefractive keratectomy (WFG PRK) in the fellow eye for myopia and myopic astigmatism correction.
  
  
  METHODS
  A prospective, randomized study of 22 eyes of 11 patients who underwent simultaneous WFG LASIK and WFG PRK (contralateral eye). Both groups were treated with the NIDEK Advanced Vision Excimer Laser System, and a microkeratome was used for flap creation in the WFG LASIK group. High and low contrast visual acuity, wavefront analysis, contrast sensitivity, and retinal straylight measurements were performed preoperatively and at 3, 6, and 12 months postoperatively. A third-generation straylight meter, C-Quant (Oculus Optikgeräte GmbH), was used for measuring intraocular straylight.
  
  
  RESULTS
  Twelve months postoperatively, mean uncorrected distance visual acuity was -0.06 +/- 0.07 logMAR in the WFG LASIK group and -0.10 +/- 0.10 logMAR in the WFG PRK group. Mean preoperative intraocular straylight was 0.94 +/- 0.12 logs for the WFG LASIK group and 0.96 +/- 0.11 logs for the WFG PRK group. After 12 months, the mean straylight value was 1.01 +/- 0.1 log s for the WFG LASIK group and 0.97 +/- 0.12 log s for the WFG PRK group. No difference was found between techniques after 12 months (P = .306). No significant difference in photopic and mesopic contrast sensitivity between groups was noted.
  
  
  CONCLUSIONS
  Intraocular straylight showed no statistically significant increase 1 year after WFG LASIK and WFG PRK. Higher order aberrations increased significantly after surgery for both groups. Nevertheless, WFG LASIK and WFG PRK yielded excellent visual acuity and contrast sensitivity performance without significant differences between techniques.
authors.affiliation: Refractive Surgery Service, Department of Ophthalmology, University of São Paulo, São Paulo, Brazil. jackbj@terra.com.br
authors.forename: Jackson
authors.initials: J
authors.lastname: Barreto
authors.forename: Mirella T S
authors.initials: MT
authors.lastname: Barboni
authors.forename: Claudia
authors.initials: C
authors.lastname: Feitosa-Santana
authors.forename: João R
authors.initials: JR
authors.lastname: Sato
authors.forename: Samir J
authors.initials: SJ
authors.lastname: Bechara
authors.forename: Dora F
authors.initials: DF
authors.lastname: Ventura
authors.forename: Milton Ruiz
authors.initials: MR
authors.lastname: Alves
mesh_terms: D000328:Adult; D015350:Contrast Sensitivity / Q000502:physiology*; D019466:Glare; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D054018:Lasers, Excimer / Q000627:therapeutic use; D008027:Light; D009216:Myopia / Q000601:surgery*; D018903:Photorefractive Keratectomy / Q000379:methods*; D011183:Postoperative Complications; D011446:Prospective Studies; D012542:Scattering, Radiation; D014792:Visual Acuity / Q000502:physiology