Related Experiment Video
Updated: Jan 30, 2026

Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter
Published on: September 16, 2025
Dynamic contour tonometry (DCT) versus Goldmann applanation tonometry (GAT) - a comparison of agreement and
Sonja Herdener1, Mona Pache, Sonja Lautebach
1Department of Ophthalmology, University of Freiburg, Killianstrasse 5, 79106 Freiburg, Germany. sonja.herdener@uniklinik-freiburg.de
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.
Related Concept Videos
Design Example: Analyzing Capacity Contours for Flood Risk Assessment
Topographic Surveying and Contours
Reabsorption and Secretion in the DCT and Collecting Duct
The distal...
The Sense of Self: Reflected Self-Appraisal and Social Comparison
Multiple Comparison Tests
It would be easy to compare two samples using a significance alpha level of 0.05. In other words, there is only one sample pair to be compared. However, it would be difficult to identify a significantly different sample if the number...
Evolutionary Relationships through Genome Comparisons

