Influence of atmospheric pressureand temperature changes on the intraocular pressure.

Abstract

Abstract Purpose Some patients questioned us whether diving and mountaineering can have an effect on their intraocular pressure (IOP). Since the results in the literature concerning mountaineering are often contradictory and the data concerning diving are very limited; we investigated if an increase in atmospheric pressure influences the IOP in a normal population. Since we clinically experienced higher pressures in the summer, we checked the temperature influence on the IOP simultaneously. Methods Twenty‐seven healthy volunteers (aged 18 to 44) were placed in a hyperbaric chamber. Their IOP was measured with a Perkins tonometer at baseline (normal atmospheric pressure of 1 Bar and 24°C), after increasing the atmospheric pressure to 2 Bar both at 14°C and 28°C, and finally at baseline again. A multivariate regression analysis was used to evaluate the results of both eyes. Results The IOP significantly decreased from 11.75mmHg to 10.50mmHg at 2 Bar. The IOP decrease remained constant during the atmospheric pressure rise (40 minutes) and was independent of the temperature change. The IOP returned back to the baseline value when exiting from the hyperbaric chamber. Conclusion A small increase of atmospheric pressure to 2 Bar (= equal effect to diving at 10m below sea level) is sufficient to lead to a significant reduction in IOP independent of temperature changes in a healthy young population. The IOP decrease sustains for the whole hyperbaric chamber period.