Is intraocular pressure same at same time on different days in normotensives?

Abstract

Purpose: To determine the variation in the intraocular pressure (IOP) at the same time on different days using Goldmann applanation tonometer in normal eyes. Materials and Methods: Two hundred eyes of hundred included subjects underwent detailed eye examination including vision assessment, slit lamp examination, baseline IOP measurement, and fundus examination. The IOP was measured on 4 days with the Goldmann applanation tonometer. The measurements were taken on consecutive days or separated by no more than one day between daily testing sessions. A difference of 1 hour on either side from the first day′s IOP reading was considered. The readings taken on 4 days were compared to find if there was any statistical difference between them. Results: There was no significant difference between the IOP′s measured at the same time on four different days in both eyes. The IOP measured in the right eye on days 1, 2, 3, 4 when compared were not statistically significant (median 12.5, 12.0, 12.0, 12.0, respectively and P-value 0.201). The IOP measured in the left eye on days 1, 2, 3, 4 when compared were also not statistically significant (median 13.0, 13.0, 12.0, 12.5, respectively and P-value 0.062). Conclusion: In normal eyes, the IOP measured using Goldmann applanation tonometer at the same time on different days within a week was not significantly different.

Keywords

• Diurnal variation
• intraocular pressure
• tonometry