title: [Comparison of central corneal thickness and keratometric measurements using the Scheimpflug HR imaging system, laser interferometry, automatic keratometry and ultrasound pachymetry].
abstract: BACKGROUND
  The aim of our study was to compare keratometry and central corneal thickness measurements obtained with three different ophthalmic devices and to decide if they can be used interchangeably in clinical practice.
  
  
  METHODS
  43 healthy persons were included in the study (29 women and 14 men, average age 25 ± 3.5 years). Central corneal thickness (CCT) was measured with the Scheimpflug HR imaging system (Pentacam), Allegro BioGraph and with ultrasound pachymetry (RXP OcuScan). Keratometry in two main meridians of the cornea (K1, K2) was measured with Pentacam, Allegro BioGraph and automated keratometry.
  
  
  RESULTS
  The mean difference in K1-readings was 0.01 ± 0.31 D for BioGraph vs. automated keratometry, 0.06 ± 0.23 D for BioGraph vs. Pentacam and 0.05 ± 0.34 D for automated keratometry and Pentacam. The mean difference in K2-readings was 0.29 ± 0.45 D for BioGraph vs. automated keratometry, 0.11 ± 0.28 D for BioGraph vs. Pentacam and 0.19 ± 0.44 D for automated keratometry and Pentacam. The interdevice differences were in all cases statistically significant (p < 0.05). The mean difference in CCT was 4.57 ± 7.84 μm for BioGraph vs. ultrasound, 4.33 ± 7.55 μm for BioGraph vs. Pentacam and 8.90 ± 7.49 μm for ultrasound vs. Pentacam. The interdevice differences in CCT were also statistically significant (p < 0.05).
  
  
  CONCLUSIONS
  Our results suggest that the measurements of keratometry and CCT may differ significantly between the tested machines and therefore should not be used interchangeably in clinical practice.
authors.affiliation: Zilinske ocne centrum VIKOM, Zilina. pasova.petra@gmail.com
authors.forename: P
authors.initials: P
authors.lastname: Pašová
authors.forename: K
authors.initials: K
authors.lastname: Skorkovská
authors.forename: J
authors.initials: J
authors.lastname: Michálek
mesh_terms: D000328:Adult; D003315:Cornea / Q000000981:diagnostic imaging; D063171:Corneal Pachymetry / Q000379:methods*; D019781:Corneal Topography; D005260:Female; D006801:Humans; D007368:Interferometry; D008297:Male; D010781:Photography; D014463:Ultrasonography