Abstract
Purpose: :
The Pascal Dynamic Contour Tonometer is a novel tonometer designed to measure IOP indipendent of corneal structure. The purpose of this study is to determine the correlation between IOP measurements performed using DCT Pascal and Goldmann applanation tonometry (GAT), as well as the intra and inter observer variability.
Methods: :
we prospectively evaluated 190 eyes of 100 POAG patients (with no previous surgeries or other ocular pathologies) who underwent complete clinical examination including GAT and DCT IOP measurements, ultrasound pachymetry, cheratometry, biometry and PENTACAM examination (central and periferic pachymetry, topography, AC depth), all performed by two different operators. Statistical analysis was made using the Pearson's r regression analysis and ANOVA.
Results: :
mean DCT values were about 2,5 mmHg higher than GAT readings. Good correlation (r2=0.55; p<0.005) between GAT and DCT was found for both the operators. Correlation between GAT and CCT was r2=0.08, p<0.05 and between DCT and CCT was r2=0.04, p<0.05. No correlation was found between DCT and A.C depth, DCT and axial lenght, DCT and cheratometry, and between DCT and periferic corneal thickness performed by pentacam.
Conclusions: :
Good intra and inter–observer repeteability of the DCT measurements was found. Further studies, possibly using intracameral manometry, are required to understand the relationship between DCT Pascal IOP measurement and true IOP values.
Keywords: intraocular pressure • shape and contour • clinical (human) or epidemiologic studies: systems/equipment/techniques