Comparison of three different methods of intraocular pressure (IOP) measurements including properties of the cornea

Abstract

AbstractPurpose The aim of this study was to show the usefullness of three different methods of Intraocular Pressure (IOP) measurements: Goldmann Applanation Tonometer, Rebound Tonometer and Ultra High‐Speed Scheimpflug Technology.Methods The examined group consisted of 96 patients, 192 eyes (63 females, 33 males of mean age 59,3±19,9 years old). IOP measurements were carried out using Goldmann Applanation Tonometer (GAT), Rebound Tonometer Icare Pro (RT) and Ultra High‐Speed Scheimpflug Technology (UHS ST) –“Corvis ST” with pachymetry which automatically took into account of central corneal thickness (CCT) correction. Additionally corneal pachymetry with Pentacam, Oculus were made to considered CCT in GAT IOP value. Statistical analysis was based on the software Statistica 10.0 PL, Statsoft, Poland.Results Mean IOP measured with GAT was 15,6±3,75 mmHg; GAT with CCT correction 15,7±3,7 mmHg; mean IOP measured with RT was 15,6±3,5 mmHg; with UHS ST 16,1±4,0 mmHg. Mean CCT measured with UHS ST was 543,7±52,7 µm; with Pentacam 547,9±54,0 µm. In comparison, there is significant difference between IOP measured with GAT and GAT+CCT, RT versus UHS ST (P<0,001) and no significant between GAT, GAT+CCT versus RT (p>0,5). Central Corneal Thickness was without differences in measurements carried out with UHS ST and Pentacam. All technics showed correlation IOP with CCT (p<0,05; r~0,3).Conclusion Applanation Tonometer and Rebound Tonometer can be equal methods of IOP measurements in contrast to Ultra High‐Speed Scheimpflug Technology which give significant different values but can be use to take accurate measurements of Central Corneal Thickness