To evaluate the repeatability and interoperator reproducibility of the Pascal dynamic contour tonometry (DCT), ocular response analyzer (ORA), and Goldmann applanation tonometer (GAT) in a single population of normal individuals.
The study included 52 eyes from 26 normal individuals. One operator measured the intraocular pressure (IOP) with each tonometer 3 times while 2 additional operators each measured the IOP with each tonometer once. Repeatability and reproducibility were assessed by the coefficient of variation (CV) and intraclass correlation coefficient (ICC). Agreement among tonometers was also assessed using Bland-Altman plots.
The mean age of included participants was 31.5±8.8 years and 15 (58%) were female individuals. In general, both intraoperator repeatability and interoperator reproducibility were significantly higher for DCT compared with the other tonometers. Intraoperator DCT (CV=3.7, ICC=0.89), GAT (CV=9.7, ICC=0.79), IOPg (CV=7.0, ICC=0.79), and IOPcc (CV=9.8, ICC=0.57). Interoperator DCT (CV=6.1, ICC=0.73), GAT (CV=9.0, ICC=0.82), and IOPg (CV=10.8, ICC=0.63), IOPcc (CV=11.7, ICC=0.49).
Overall, DCT was significantly more repeatable and reproducible than GAT, IOPg and IOPcc. The better reproducibility of the DCT may result in more precise measurements for monitoring IOP changes over time compared to GAT and ORA.
*Department of Ophthalmology, Hamilton Glaucoma Center, University of California at San Diego, La Jolla, CA
†Case Western Reserve University School of Medicine, Cleveland, OH
‡Department of Ophthalmology, University of São Paulo, São Paulo, Brazil
Grant Support: NIH NEI EY08208.
Financial Disclosure: Carl Zeiss: F.A.M. (F, R), Heidelberg Engineering: F.A.M. (R), Reichert Inc : F.A.M. (R), R.N.W. (R), Ziemer Ophthalmic Systems AG: F.A.M. (R), R.N.W. (R).
Reprints: Felipe A. Medeiros, MD, Hamilton Glaucoma Center, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0946 (e-mail: firstname.lastname@example.org).
Received December 13, 2010
Accepted May 16, 2011