title: One-year results from the phase III investigation of the KeraVision Intacs.
abstract: BACKGROUND
  Limitations of the surgical correction for myopia include inaccuracy, instability, treatment of the central optical zone, and lack of reversibility. KeraVision Intacs offer an alternative that addresses these shortcomings.
  
  
  METHODS
  We present 1 year of follow-up information on 95 subjects enrolled in the United States Food and Drug Administration Phase III clinical trials.
  
  
  RESULTS
  At 1 year, 99% of patients (89 of 90) had 20/40 uncorrected vision or better. Ninety-two percent of eyes (83 of 90) were within 1.00 D of intended correction and 76% of eyes (68 of 90) were within 0.50 D of intended correction. Stability was achieved at 3 months, with 96% of subjects (86 of 90) having less than 1.00 D of change from their previous examination. In a substudy, 89% eyes (58 of 65) varied within +/- 0.50 D over the course of a day. Corneal curvature changed as predicted, resulting in a prolate aspheric shape within the central optical zone. Most complications or adverse events experienced were managed with additional medication or surgical intervention, resulting in a favorable outcome for subjects.
  
  
  CONCLUSIONS
  KeraVision Intacs are effective, predictable, stable, and safe. This additive technique may also offer reversibility.
authors.affiliation: Shiley Eye Center, University of California-San Diego, La Jolla, USA.
authors.forename: M D
authors.initials: MD
authors.lastname: Twa
authors.forename: P M
authors.initials: PM
authors.lastname: Karpecki
authors.forename: B J
authors.initials: BJ
authors.lastname: King
authors.forename: S H
authors.initials: SH
authors.lastname: Linn
authors.forename: D S
authors.initials: DS
authors.lastname: Durrie
authors.forename: D J
authors.initials: DJ
authors.lastname: Schanzlin
mesh_terms: D000328:Adult; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000601:surgery*; D019736:Prostheses and Implants / Q000009:adverse effects; D019919:Prosthesis Implantation; D016896:Treatment Outcome