Comparison of Intraocular Pressure Measurements With the Reichert Pt100, the Keeler Pulsair Intellipuff Portable Noncontact Tonometers, and Goldmann Applanation Tonometry

Purpose:The aim of this study was to compare intraocular pressure (IOP) measurements using 2 portable tonometers, the Keeler Pulsair Intellipuff and the Reichert PT100, with Goldmann applanation tonometry (GAT).Materials and Methods:Prospective cross-sectional study was conducted on normotensive and hypertensive patients recruited from the outpatient clinic of the University Hospital of Grenoble. IOP was measured using 2 portable noncontact tonometers (NCTs) and GAT in one eye of each patient in a random order. Central corneal thickness was measured with the Accutome PachPen Pachymeter. The Wilcoxon and t tests were used to compare the differences between tonometers, the Pearson and the Spearman correlation tests to evaluate the correlation among the methods, and the Bland-Altman plots to evaluate the agreement among the methods. Intraclass correlation coefficient (ICC) was used to evaluate the agreement among the methods in normotensive and hypertensive patients separately.Results:A total of 137 eyes of 137 patients were included, 104 normotensive and 33 hypertensive eyes. We found an excellent agreement between PT100 and GAT (ICC=0.77) and between Intellipuff and GAT (ICC=0.75) in normotensive patients. We found a fair to good agreement (ICC=0.67) between PT100 and GAT in hypertensive patients. The agreement we found between Intellipuff and GAT was also excellent in hypertensive patients (ICC=0.86). Both NCTs significantly overestimated IOP measurements compared with GAT in normotensive and hypertensive eyes (mean of the differences between PT100 and GAT: 1.32.1 and 8.1 +/- 4.6 mm Hg in normotensive and in hypertensive patients, respectively (P<0.05), and between Pulsair Intellipuff and GAT: 1.5 +/- 1.8 and 2.3 +/- 4.8 mm Hg in normotensive and in hypertensive patients, respectively (P<0.05).Conclusions:The 2 NCTs agree well with GAT in normotensive patients. The Pulsair Intellipuff also agrees well with GAT in hypertensive patients.