title: Corneal Collagen Cross-linking for the Treatment of Progressive Corneal Ectasia: 6-Year Prospective Outcome in a French Population.
abstract: OBJECTIVE
  To evaluate 6-year results of standardized epithelium-off corneal collagen cross-linking (CXL) for treatment of progressive corneal ectasia.
  
  
  METHODS
  Prospective, consecutive, interventional case series.
  
  
  METHODS
  Thirty-six eyes of 25 consecutive patients with documented progressive primary or iatrogenic corneal ectasia underwent CXL following the Siena protocol. The main outcome measures included uncorrected (UDVA) and corrected (CDVA) distance visual acuities, biomicroscopy and fundus appearance, topography-derived steep and flat keratometry (Kmax, Kmin), central corneal thickness (CCT), intraocular pressure with Goldmann applanation tonometer (GAT-IOP), and endothelial cell density (ECD), recorded at baseline and months 1, 3, 6, 12, 24, 36, and 72. Bilateral macular optical coherence tomography was performed at the endpoint visit. The mean follow-up was 66 ± 6 months (range, 60-78 months).
  
  
  RESULTS
  At 6 years, CXL stabilized primary and iatrogenic corneal ectasia in 89% of the patients. In bilateral CXL, the progression of the first eye was highly predictive of the fellow eye's outcome. At the endpoint follow-up, the mean outcome variations were: UDVA: -0.08 ± 0.36 logMAR (P = .2); CDVA: -0.14 ± 0.28 logMAR (P = .004); Kmax: +0.11 ± 1.70 diopters (D) (P = .7); Kmin: -0.25 ± 1.25 D (P = .2); CCT: -16.38 ± 37 μm (P = .01); GAT-IOP: +1.0 ± 2.3 mm Hg (P = .01); ECD: +31 ± 400 cells/mm(2) (P = .6); no cases of macular toxicity or severe adverse events were reported.
  
  
  CONCLUSIONS
  At 6 years, CXL maintains long-term results in halting the progression of corneal ectasia, with significant improvement in CDVA and long-term stability of keratometry. Further clinical studies with longer follow-up and larger series would be necessary to definitely confirm these results.
authors.affiliation: Clinique Ophtalmologique, Centre Hospitalier Universitaire Edouard Herriot, Lyon, France. Electronic address: muriel.poli@chu-lyon.fr.
authors.forename: Muriel
authors.initials: M
authors.lastname: Poli
authors.affiliation: Clinique Ophtalmologique, Centre Hospitalier Universitaire Edouard Herriot, Lyon, France.
authors.forename: Amélie
authors.initials: A
authors.lastname: Lefevre
authors.affiliation: Banque des tissus et cornées, Centre Hospitalier Universitaire Edouard Herriot, Lyon, France.
authors.forename: Céline
authors.initials: C
authors.lastname: Auxenfans
authors.affiliation: Clinique Ophtalmologique, Centre Hospitalier Universitaire Edouard Herriot, Lyon, France.
authors.forename: Carole
authors.initials: C
authors.lastname: Burillon
mesh_terms: D000293:Adolescent; D000328:Adult; D003094:Collagen / Q000378:metabolism*; D003316:Corneal Diseases / Q000175:diagnosis / Q000188:drug therapy* / Q000378:metabolism; D063171:Corneal Pachymetry; D003319:Corneal Stroma / Q000378:metabolism*; D019781:Corneal Topography; D003432:Cross-Linking Reagents; D004108:Dilatation, Pathologic / Q000188:drug therapy / Q000378:metabolism; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005602:France; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D011446:Prospective Studies; D012256:Riboflavin / Q000627:therapeutic use*; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome; D014466:Ultraviolet Rays; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult
chemical_list: D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin