title: Effects of Corneal Collagen Crosslinking on Confocal Microscopic Findings and Tear Indices in Patients with Progressive Keratoconus.
abstract: BACKGROUND
  To evaluate any change in tear indices and confocal microscopic findings after corneal collagen crosslinking (CXL) in patients with progressive keratoconus.
  
  
  METHODS
  Thirty-two consecutive eyes from 23 patients having progressive keratoconus were enrolled in this prospective, interventional cohort study. The standard crosslinking surgery was performed for all patients. Visual, refractive, and topographic evaluations were done before and at 6 months after surgery. Tear function tests and confocal microscopic examination were performed before and at 1 month and 6 months after the procedure.
  
  
  RESULTS
  There was no significant change in Schirmer-1 test results and tear osmolarity at 1 month and 6 months after CXL. Using confocal microscopy, all eyes showed reduced or absent subepithelial nerve plexus. Differences in basal epithelial cell density, epithelial mean cell area, and keratocyte density in anterior and middle stroma and endothelial cell pleomorphism were all significant at 1 month and 6 months after CXL (P< 0.05). No significant change was noted in endothelial cell count and their polymegathism at 6 months follow-up. Significant improvement was noted in uncorrected visual acuity, best corrected visual acuity, flattest corneal meridian (K2), and maximum keratometry in Pentacam (Kmax) after 6 months of the procedure.
  
  
  CONCLUSIONS
  While CXL would have no effect on tear indices and endothelial cell count, it can cause a significant reduction in subepithelial nerve plexus and significant alterations in epithelial cell density in the anterior and middle stroma.
authors.affiliation: Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Zare
authors.affiliation: Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Mazloumi
authors.affiliation: Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran; Department of Ophthalmology, Kashan University of Medical Sciences, Kashan, Iran.
authors.forename: Hasan
authors.initials: H
authors.lastname: Farajipour
authors.affiliation: Iran Eye Bank, Tehran, Iran.
authors.forename: Bagher
authors.initials: B
authors.lastname: Hoseini
authors.affiliation: Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad R
authors.initials: MR
authors.lastname: Fallah
authors.affiliation: Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Hadi Z
authors.initials: HZ
authors.lastname: Mahrjerdi
authors.affiliation: Isfahan Eye Research Center, Feiz Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mohammad-Ali
authors.initials: MA
authors.lastname: Abtahi
authors.affiliation: Isfahan Eye Research Center, Feiz Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Seyed-Hossein
authors.initials: SH
authors.lastname: Abtahi
keywords: Confocal microscopy; corneal collagen crosslinking; keratoconus