Evaluation of Changes in Intraocular Pressure with a Noncontact Tonometer in Healthy Volunteers

We investigated whether or not intrasession or intersession fluctuations in intraocular pressure occur in healthy people using a noncontact tonometer.

A noncontact tonometer was used to measure intraocular pressure in the bilateral eyes of healthy subjects for 5 consecutive days. Paired t-tests and one- and two-way repeated-measures analyses of variance were performed for the acquired data. A p-value <0.05 was considered to indicate statistical significance.

Eighty eyes of 40 healthy subjects were enrolled in the study. On day 1, intraocular pressure was significantly higher in the right eye than in the left eye (P = 0.014). The one-way repeated-measures analysis of variance revealed that intraocular pressure in the left eye was significantly lower on day 1 than on days 2 to 5 (P = 0.000-0.018); however, there were no significant differences among intraocular pressures measured on days 1 to 5 in the right eye. The two-way repeated-measures analysis of variance revealed no significant difference in intraocular pressure between the right and left eyes (P = 0.913).

Although measurements using the noncontact tonometer were relatively stable, intraocular pressure was high on day 1.