title: Wavefront-guided LASIK for the correction of primary myopia and astigmatism a report by the American Academy of Ophthalmology.
abstract: OBJECTIVE
  To describe wavefront-guided (WFG) LASIK for the primary treatment of low to moderate levels of myopia and astigmatism and to examine the evidence on the safety and effectiveness of the procedure in comparison with conventional LASIK.
  
  
  METHODS
  Literature searches conducted in 2004, 2005, 2006, and 2007 retrieved 209 unique references from the PubMed and Cochrane Library databases. The panel selected 65 articles to review, and of these, chose 45 articles that they considered to be of sufficient clinical relevance to submit to the panel methodologist for review. During the review and preparation of this assessment, an additional 2 articles were included. A level I rating was assigned to properly conducted, well-designed, randomized clinical trials; a level II rating was assigned to well-designed cohort and case-controlled studies; and a level III rating was assigned to case series, case reports, and poorly designed prospective and retrospective studies. In addition, studies that were conducted by laser manufacturers before device approval (premarket approval) were reviewed as a separate category of evidence.
  
  
  RESULTS
  The assessment describes studies reporting results of WFG LASIK clinical trials, comparative trials, or both of WFG and conventional LASIK that were rated level II and level III. There were no studies rated as level I evidence. Four premarket approval studies conducted by 4 laser manufacturers were included in the assessment. The assessment did not compare study results or laser platforms because there were many variables, including the amount of follow-up, the use of different microkeratomes, and the level of preoperative myopia and astigmatism.
  
  
  CONCLUSIONS
  There is substantial level II and level III evidence that WFG LASIK is safe and effective for the correction of primary myopia or primary myopia and astigmatism and that there is a high level of patient satisfaction. Microkeratome and flap-related complications are not common but can occur with WFG LASIK, just as with conventional LASIK. The WFG procedure seems to have similar or better refractive accuracy and uncorrected visual acuity outcomes compared with conventional LASIK. Likewise, there is evidence of improved contrast sensitivity and fewer visual symptoms, such as glare and halos at night, compared with conventional LASIK. Even though the procedure is designed to measure and treat both lower- and higher-order aberrations (HOAs), the latter are generally increased after WFG LASIK. The reasons for the increase in HOA are likely multifactorial, but the increase typically is less than that induced by conventional LASIK. No long-term assessment of WFG LASIK was possible because of the relatively short follow-up (12 months or fewer) of most of the studies reviewed.
authors.affiliation: American Academy of Ophthalmology, Quality Care and Knowledge Base Development, P.O. Box 7424, San Francisco, CA 94120-7424, USA.
authors.forename: Steven C
authors.initials: SC
authors.lastname: Schallhorn
authors.forename: Ayad A
authors.initials: AA
authors.lastname: Farjo
authors.forename: David
authors.initials: D
authors.lastname: Huang
authors.forename: Brian S
authors.initials: BS
authors.lastname: Boxer Wachler
authors.forename: William B
authors.initials: WB
authors.lastname: Trattler
authors.forename: David J
authors.initials: DJ
authors.lastname: Tanzer
authors.forename: Parag A
authors.initials: PA
authors.lastname: Majmudar
authors.forename: Alan
authors.initials: A
authors.lastname: Sugar
mesh_terms: D000047:Academies and Institutes / Q000458:organization & administration; D001251:Astigmatism / Q000601:surgery*; D015350:Contrast Sensitivity; D003319:Corneal Stroma / Q000601:surgery*; D019781:Corneal Topography; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D054018:Lasers, Excimer / Q000009:adverse effects / Q000627:therapeutic use*; D009216:Myopia / Q000601:surgery*; D009885:Ophthalmology / Q000458:organization & administration; D017060:Patient Satisfaction; D013524:Surgical Flaps; D013673:Technology Assessment, Biomedical; D016896:Treatment Outcome; D014792:Visual Acuity