Harald Kramer1,
2, Amanda R. Corcos3, Diego Hernando4, John F.
Berry3, Mark L. Schiebler1, Scott B. Reeder1
1Department
of Radiology, University of Wisconsin - Madison, Madison, WI, United States; 2Institute
for Clinical Radiology, Ludwig-Maximilians-University Munich, Munich,
Bavaria, Germany; 3Department of Chemistry, University of
Wisconsin - Madison, Madison, WI, United States; 4Department of
Radiology, University of Wisconsin-Madison, Madison, WI, United States
Oxygen is paramagnetic and known to influence the relaxation properties of tissues in MRI. Little is known regarding the dependence of oxygen partial pressure on relaxation times (T1 and T2) in fluids. We performed relaxometry experiments in a phantom with varying oxygen partial pressure ranging from 0-760mmHg at clinical field strength. Using measured values of T1 and T2 at different oxygen tensions permitted calculation of the relaxivities (r1 and r2) of oxygen. Differences in oxygen tension can be visualized and quantified with MRI. The results suggest that the injection of oxygen saturated/desaturated saline could be used as a contrast agent.