Related Experiment Video
Updated: Jul 14, 2026

Combining Volumetric Capnography And Barometric Plethysmography To Measure The Lung Structure-function Relationship
Published on: January 8, 2019
[Comparison of dynamic contour tonometry (Pascal) with pneumotonometry and Goldmann tonometry]
H Heras-Mulero1, J Moreno-Montañés, L M Sádaba Echarri
1Departamento de Oftalmología, Clínica Universitaria de Navarra, Pamplona (Navarra), España. henarheras@yahoo.es
Purpose:
To compare the intraocular pressure measurements as defined by the Pascal tonometer, the Goldmann tonometer and the pneumotonometer.
Methods:
This was an observational clinical study, which included two hundred and five randomly selected subjects recruited from the Ophthalmology Department. The intraocular pressure measurements were performed with each tonometry technique in a randomized order.
Results:
The Pascal's intraocular pressure measurement was significantly higher than that measured by the other two tonometers (p<0.05). The quality data of Pascal was: optimum in 27.3% (56 of 205 patients), acceptable in 42% (86 of 205 patients) and unacceptable in 23.4% (48 of 205 patients). In 7.3% (15 of 205 patients) it was impossible to obtain any measurement using Pascal. A weak correlation coefficient between the Pascal and the Goldmann, and between Pascal and the pneumotonometer was found. The Bland-Altman method of measurement using these tonometers showed a high degree of discordance.
Conclusion:
As reported by others authors, the Pascal's intraocular pressure measurement is higher than that of the Goldmann tonometer. The measurement differs from 0.7 to 4.4 mmHg. In corneas with pathology, it is very difficult or even unacceptable to measure the intraocular pressure using the Pascal tonometer.
Related Concept Videos
Assessment of Diffusion and Perfusion
The Role of Diffusion in Respiration
Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. In the respiratory system, this principle...
Static, Stagnation, Dynamic and Total Pressure
Measurement of Blood Pressure
Physical Assessment of the Respiratory Tract III: Percussion
Percussion in Respiratory Assessment
Percussion evaluates underlying tissue composition with audible and tactile vibrations,...
