title: Long-term results of corneal collagen crosslinking for progressive keratoconus.
abstract: OBJECTIVE
  To evaluate long-term keratoconus stability after corneal crosslinking (CXL) with riboflavin.
  
  
  METHODS
  In this prospective study, 57 eyes of 55 patients with progressive keratoconus, consecutively treated with ultraviolet A (UVA) - riboflavin CXL, were examined with the corneal topographer Pentacam, the biometer IOLMaster and the analyzer of corneal biomechanics Ocular Response Analyzer before and during a 24 months follow-up after CXL.
  
  
  RESULTS
  Twenty-four months after CXL, there was a significant improvement in best corrected visual acuity (BCVA) (P<0.01), a significant decrease in corneal thinnest point (CTP), keratometry readings at the keratoconus apex (K max), and corneal volume (CV) (P<0.01), and a significant increase in axial eye length (AL) (P=0.01). No significant changes in anterior chamber volume (ACV) and depth (ACD), (P=0.8), corneal hysteresis (CH) (P=0.16) and corneal resistance factor (CRF) (P=0.06) were found. However, in the subgroup of patients with decreased K max readings 24 months after treatment, both CH and CRF showed a significant reduction (P<0.01).
  
  
  CONCLUSIONS
  In the first month after the procedure, CXL induces a reduction in corneal volume. During the 24 months follow-up the cornea tends to recover its original volume with a persistence of the CXL efficacy.
authors.affiliation: Department of Medicine and Surgery, University of Salerno, Salerno, Italy.
authors.forename: Maddalena
authors.initials: M
authors.lastname: De Bernardo
authors.affiliation: U.O.C. Prelievo e Trapianto Cornee, Pellegrini Hospital, Naples, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Capasso
authors.affiliation: 2nd University of Naples, Naples, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Lanza
authors.affiliation: U.O.C. Prelievo e Trapianto Cornee, Pellegrini Hospital, Naples, Italy.
authors.forename: Antonia
authors.initials: A
authors.lastname: Tortori
authors.affiliation: Department of Medicine and Surgery, University of Salerno, Salerno, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Iaccarino
authors.affiliation: Department of Medicine and Surgery, University of Salerno, Salerno, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Cennamo
authors.affiliation: 2nd University of Naples, Naples, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Borrelli
authors.affiliation: Department of Medicine and Surgery, University of Salerno, Salerno, Italy. Electronic address: nrosa@unisa.it.
authors.forename: Nicola
authors.initials: N
authors.lastname: Rosa
mesh_terms: D000293:Adolescent; D000328:Adult; D058452:Axial Length, Eye; D002648:Child; D003094:Collagen / Q000378:metabolism; D003315:Cornea / Q000502:physiology; D019781:Corneal Topography; D003432:Cross-Linking Reagents / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D011446:Prospective Studies; D012256:Riboflavin / Q000627:therapeutic use*; D014792:Visual Acuity; D055815:Young Adult
chemical_list: D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin
keywords: Axial eye length; Corneal crosslinking; Corneal thinnest point; Cross-linking corneal; Grosor corneal más delagado; Keratoconus; Keratometry readings; Longitud axial del ojo; Mediciones del queratómetro; Queratocono