COMPARATIVE AGREEMENT AMONG THREE METHODS OF TONOMETRY:GOLDMANN APPLANATION,TRANSPALPEBRAL AND DYNAMIC CONTOUR
Purpose: To investigate agreement of intraocular pressure (IOP) as measured by the Goldmann applanation tonometer (GAT), the Pascal dynamic contour tonometer (DCT), and Diaton transpalpebral tonometer (DTT).
Methods: Device agreement was calculated by Bland-Altman analysis in 77 eyes of 40 individuals (mean age 58.9 ± 13 years) with a mixed diagnosis of glaucoma suspicion and primary open-angle glaucoma. All measurements were performed in a random order by the same clinician according to standard procedures.
Results: Mean IOPs ± S.D. were 14.4 ± 2.9 mm Hg (GAT), 18.8 ± 3.2 mm Hg (DCT; P = 0.005, ANOVA), and 15.1 ± 3.1 mm Hg (DTT). Bland-Altman analysis demonstrated that, on average, DCT IOP measurements overestimated in approximately 3 mm Hg, values derived from GAT and DTT, although agreement was fairly good.
Conclusions: All methods of tonometry were adequate to measure IOP in our sample. Agreement among devices was considered good;nevertheless, DCT values of IOP were significantly higher as compared to the other two assessed methods.