[Influence of corneal thickness in keratoconic corneas on IOP measurement with IOPen, iCare, dynamic contour tonometry and Goldmann applanation tonometry]

Klin Monbl Augenheilkd. 2013 Jul;230(7):697-700. doi: 10.1055/s-0032-1328408. Epub 2013 May 13.
[Article in German]

Abstract

Background: The aim of this study was to evaluate the effect of central corneal thickness (CCT) of keratoconic corneas on intraocular pressure (IOP) measurements as measured by four different techniques.

Patients and methods: Forty-one eyes of forty-one keratoconus patients (group 1) and fifty eyes of fifty healthy subjects (group 2) were enrolled. IOP was measured with iCare, IOPen, Goldmann applanation tonometry (GAT) and dynamic contour tonometry (DCT). CCT was measured by ultrasonic pachymetry. These data were used for statistical analysis.

Results: The mean IOPs measured by GAT, DCT, iCare and IOPen were 11.4, 14.7, 10.8, and 15.7 mmHg in group 1; and 14.2, 15.4, 15.4 and 14.3 mmHg in group 2, respectively. Between both groups, there was a statistically significant difference in iCare (p < 0.001), GAT (p < 0.001) and IOPen (p = 0.040) measurements; with no difference between DCT (p = 0.266) measurements. IOPen measurements were significantly associated with CCT (r = - 0.314; p = 0.046).

Conclusion: IOPen seemed to be affected by CCT. IOP readings by iCare, GAT and DCT were found to be independent of CCT in keratoconic corneas.

Publication types

  • Comparative Study
  • Evaluation Study

MeSH terms

  • Adult
  • Cornea / diagnostic imaging*
  • Cornea / physiopathology*
  • Corneal Topography / methods
  • Female
  • Humans
  • Intraocular Pressure*
  • Keratoconus / diagnosis*
  • Keratoconus / physiopathology*
  • Male
  • Manometry / methods*
  • Middle Aged
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Ultrasonography / methods*