title: Intacs for the correction of keratoconus: two-year follow-up.
abstract: OBJECTIVE
  To evaluate the long-term safety and efficacy of Intacs segments (Addition Technology, Inc.) for the treatment of keratoconus in terms of intraoperative and postoperative complications, visual outcome, restoration of contact lens tolerance, and inhibition of disease progression.
  
  
  METHODS
  Service d'Ophtalmologie, CHU Pellegrin, Bordeaux, France.
  
  
  METHODS
  This prospective, 2-year follow-up study comprised 100 keratoconic eyes with clear central corneas and contact lens intolerance. The best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), refractive error, keratometry, pachymetry, and slitlamp examination were assessed preoperatively and 1 and 2 years after Intacs implantation.
  
  
  RESULTS
  At 2 years, the UCVA and BCVA improved in 80.5% and 68.3% of eyes, respectively (P<.001). The proportion of eyes with a BCVA >or=0.5 (20/40) increased from 22.0% at baseline to 51.2% and 53.7% at 1 year and 2 years, respectively (P<.001). The manifest refraction spherical equivalent improved from a mean of -6.93 diopters (D) +/- 3.91 (SD) preoperatively to -4.01 +/- 3.16 D at 1 year and -3.80 +/- 2.73 D at 2 years (P<.001). The mean keratometry readings decreased from 50.1 +/- 5.6 D preoperatively to 46.4 +/- 5.3 D at 1 year and 46.8 +/- 4.9 D at 2 years (P<.001). Contact lens tolerance was restored in over 80% of cases. Postoperative slitlamp observations revealed no clinically significant issues. The segments were removed from 4 eyes without complications or sequelae.
  
  
  CONCLUSIONS
  Intacs implantation was a safe and efficacious treatment for keratoconus. Significant and sustained improvements in objective visual outcomes were achieved in most cases, with restoration of contact lens tolerance.
authors.affiliation: Service d'Ophtalmologie, CHU Pellegrin, Bordeaux, France. joseph.colin@chu-bordeaux.fr
authors.forename: Joseph
authors.initials: J
authors.lastname: Colin
authors.forename: Florence J
authors.initials: FJ
authors.lastname: Malet
mesh_terms: D001672:Biocompatible Materials; D003261:Contact Lenses; D003319:Corneal Stroma / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007431:Intraoperative Complications; D007640:Keratoconus / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D019904:Polymethyl Methacrylate; D011183:Postoperative Complications; D011446:Prospective Studies; D019736:Prostheses and Implants; D019919:Prosthesis Implantation; D014792:Visual Acuity / Q000502:physiology
chemical_list: D001672:Biocompatible Materials; D019904:Polymethyl Methacrylate