title: Scheimpflug imaged corneal changes on anterior and posterior surfaces after collagen cross-linking.
abstract: OBJECTIVE
  To compare the anterior and posterior corneal parameters before and after collagen cross-linking therapy for keratoconus.
  
  
  METHODS
  Collagen cross-linking was performed in 31 eyes of 31 keratoconus patients (mean age 30.6±8.9y). Prior to treatment and an average 7mo after therapy, Scheimpflug analysis was performed using Pentacam HR. In addition to corneal thickness assessments, corneal radius, elevation, and aberrometric measurements were performed both on anterior and posterior corneal surfaces. Data obtained before and after surgery were statistically analyzed.
  
  
  RESULTS
  In terms of horizontal and vertical corneal radius, and central corneal thickness no deviations were observed an average 7mo after operation. Corneal higher order aberration showed no difference neither on anterior nor on posterior corneal surfaces. During follow-up period, no significant deviation was detected regarding elevation values obtained by measurement in mm units between the 3.0-8.0 mm-zones.
  
  
  CONCLUSIONS
  Corneal stabilization could be observed in terms of anterior and posterior corneal surfaces, elevation and higher order aberration values 7mo after collagen cross-linking therapy for keratoconus.
authors.affiliation: Orbident Refractive Surgery and Medical Center, Debrecen 4032, Hungary.
authors.forename: Ziad
authors.initials: Z
authors.lastname: Hassan
authors.affiliation: Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen 4012, Hungary.
authors.forename: Laszlo
authors.initials: L
authors.lastname: Modis
authors.affiliation: Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen 4012, Hungary.
authors.forename: Eszter
authors.initials: E
authors.lastname: Szalai
authors.affiliation: Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen 4012, Hungary.
authors.forename: Andras
authors.initials: A
authors.lastname: Berta
authors.affiliation: Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen 4012, Hungary.
authors.forename: Gabor
authors.initials: G
authors.lastname: Nemeth
keywords: collagen cross-linking; corneal back surface; elevation; high resolution Pentacam; higher order aberration