Abstract
Purpose::
Some patients ask whether diving can induce changes in the intraocular pressure (IOP). We investigated if an increase in atmospheric pressure (diving) influenced the IOP in a normal population.
Methods::
The IOP of 27 healthy volunteers (aged 18-44) was measured with a Perkins applanation tonometer by two independent investigators, who were masked from the previous measurements, at baseline (normal atmospheric pressure of 1 Bar and 24°C), after increasing the atmospheric pressure to 2 Bar in a hyperbaric oxygen tank both at 28°C and 24°C, at baseline again and finally at 28°C and normal atmospheric pressure. Multivariate regression analysis was used to evaluate the results (right eye = RE, and left eye= LE).
Results::
The mean IOP decreased from 11.8 mmHg (RE) and 11.7 mmHg (LE) at 1 Bar to 10.7 mmHg (RE) and 10.3 mmHg (LE) at 2 Bar (p= 0.024 RE and p= 0.0006 LE). The IOP decrease remained constant during the atmospheric pressure rise (50 minutes) and was independent of the temperature change. The temperature increase did not significantly influence the IOP.
Conclusions::
An increase of the atmospheric pressure to 2 Bar (= diving at 10 meter below sea level) gave a small but statistically significant decrease in IOP independent of the temperature change. The IOP decrease remained stable during the increase in atmospheric pressure (50').
Clinical Trial::
ML 3129 Ethical Committee KULeuven Belgium
Keywords: intraocular pressure • clinical (human) or epidemiologic studies: risk factor assessment • hypoxia