title: Dynamic contour tonometry (DCT) versus Goldmann applanation tonometry (GAT) - a comparison of agreement and reproducibility.
abstract: BACKGROUND
  The PASCAL dynamic contour tonometer (DCT) is a novel device designed for intraocular pressure (IOP) measurements. It is assumed to be largely independent of corneal properties. In a previous study we compared DCT with Goldmann applanation tonometry (GAT) in 100 right eyes with normal corneas. The aim of the present study is to evaluate whether differences DCT-GAT >or= 2.0 mmHg found in the previous study are reproducible and also present in the fellow eye.
  
  
  METHODS
  Twenty-three of the 100 patients (M:F = 8:15, mean age: 36 +/- 11 SD, range 22-53 years) with a previous difference DCT-GAT >or= 2.0 mmHg were included in the present study. The minimum interval between the initial and the current examination was 3 weeks. The IOP-values of the fellow eyes in this subgroup were assessed in parallel.
  
  
  RESULTS
  The difference DCT-GAT was 2.44 +/- 0.4 SEM mmHg in the subgroup of the 23 right eyes and 2.03 +/- 0.5 SEM mmHg for the fellow eyes, compared to 0.94 +/- 0.5 SEM mmHg in the initial sample of 100 eyes.
  
  
  CONCLUSIONS
  In cases with higher difference between DCT-GAT, the difference is reproducible and even present in the fellow eye. We, therefore, assume that the differences are not caused by chance, but by differing biomechanical corneal properties.
authors.affiliation: Department of Ophthalmology, University of Freiburg, Killianstrasse 5, 79106 Freiburg, Germany. sonja.herdener@uniklinik-freiburg.de
authors.forename: Sonja
authors.initials: S
authors.lastname: Herdener
authors.forename: Mona
authors.initials: M
authors.lastname: Pache
authors.forename: Sonja
authors.initials: S
authors.lastname: Lautebach
authors.forename: Jens
authors.initials: J
authors.lastname: Funk
mesh_terms: D000328:Adult; D003315:Cornea / Q000033:anatomy & histology; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D014065:Tonometry, Ocular / Q000295:instrumentation / Q000379:methods*