Accurate time interval in repeated tonometry

Abstract

Purpose: Determination of the accurate interval between the measurements in repeated tonometry. Methods: Two hundred-and-seventy subjects were randomly divided into 6 groups. Two successive intraocular pressure (IOP) measurements were performed with Goldmann-type applanation tonometer at different time intervals in each group. The time intervals between the two measurements were 1, 2, 3, 4, 5 and 10 minutes. The results in each group were statistically analyzed with the significance test for matched observations. Results: We recorded a statistically significant difference between the first and the second IOP measurements at 1, 3, 4 and 5-minute-intervals. The differences were not significant at 2 and 10 minute-groups. Conclusion: The time interval between successive IOP measurements should be 2 or 10 minutes for accurate tonometry.