97th DOG Annual Meeting 1999
INFLUENCE OF HYPERBARIC OXYGENATION ON INTRA-OCULAR PRESSURE AND PULSATILE OCULAR BLOOD FLOW
G. Rössler', R. Krott', B. Engels', D. Krauss2, C. P. Jonescu-Cuypers1,
Hyperbaric oxygenation (HBO) has been proposed as a treatment for various diseases including ophthalmological disorders of vascular or ischemic origin. Nonetheless there is little evidence about the influence of hyperbaric exposure (HBE) and HBO on intraocular pressure (IOP) and on pulsatile ocular blood flow (pOBF). Purpose of this study was to examine IOP and pOBF under various hyperbaric conditions.
Methods: Twenty-four eyes of 12 healthy volunteers (recreational divers, 7 men and 5 women, mean age 28 yrs) with a refraction of -0.5 sph (-1,75 to +1,25) were exposed to various pressures in a multiplace HBO-chamber (Starmed 2200/5, HAUX, Germany). IOP and pOBF measurements (Tonometer Serial MC6131, O.B.F. Labs Ltd., UK) were taken consecutively at ambient pressure (100kPa) - 300-160-130 kPa before and after oxygenation as well as after pressurization again at 100 kPa. Transcutaneous oxygen pressures (tcpO2) were recorded simultaneously. Statistic analysis was performed with the t-tests for paired samples.
Results: IOP continuously decreased from 16.4 mmHg before to 12.5 mmHg after the protocol (mean diff. 3.8, p<0.000 1). No effect of additional oxygenation was found. Mean pOBF increased from 1230 µl/min at 100 kPa to 1435 µl/min at 300 kPa (p=0.015) and showed a trend to increase with tcp02. No difference was found for mean pOBF values before and after HBO.
Conclusions: HBO seems to lower IOP and to increase pOBF. Additional oxygenation has no effect on IOP. Its influence on pOBF needs to be further clarified.
Dep. of Ophthalmology', University of Cologne, D-50924 Cologne
Hyperbaric Medical Center2, Weyertal 76, D-50931 Cologne
Köln Fortune Grant 120/1998