Haya M Al Farhan
King Saud University
Saudi Arabia
Title: A comparison of three techniques of intraocular pressure measurements in normal eyes
Biography
Biography: Haya M Al Farhan
Abstract
To compare the precision of Intraocular Pressure (IOP) measurements taken with ORA, TRK-1P, and GAT in healthy eyes. Design: Prospective study. Methods: One eye of fifty seven normal subjects was randomly selected and included in this study. The measurements of the IOP using ORA, TRK-1P, and GAT, and measurements CH, CRF, and CCT were taken with the ORA. Repeatability was assessed by the Coefficient of Variation (CV) and Interclass Correlation Coefficients (ICC). Repeated-measures analysis of variance (ANOVA) was used to test the statistical significance of the repeatability of three intra-observer readings. Agreement among tonometers was assessed by Bland-Altman plots and the one way-ANOVA. Results: The average of IOP for the IOPg, IOPcc, TRK-1P, and GAT (±SD) were 15.13±2.76, 14.39±2.59, 16.54±2.93, and 15.21±2.54 mmHg respectively. The intraobserver were higher for GAT and IOPg compare to TRK-1P. The intra observer for IOPg, TRK-1P, and GAT (CV= 4.99, ICC=0.93), (CV=6.69, ICC=0.86), and (CV=4.22, ICC=0.94) respectively. The Repeated-measures analysis of variance, P values for ORA, TRK-1P, and GAT were 0.13, 0.01, and 0.60 respectively. The results of the one way-ANOVA for the three instruments was statistically significant (P= 0.01). The comparison pair test P values for GAT vs. IOPg, GAT vs. 1OPcc were (p>0.05), and GAT vs. TRK-1P, TRK-1P vs. 1OPg, and TRK-1P vs. IOPcc were (p<0.05). Conclusion: GAT and IOPg were significantly more repeatable than TRK-1P. Both IOPg and IOPcc have good agreement with GAT on normal subjects.