Michael C. Langham1, Jeremy Magland1, Charles L. Epstein2, Thomas F. Floyd3, Felix W. Wehrli1
1Radiology, University of Pennsylvania, Philadelphia, PA, USA; 2Mathematics, University of Pennsylvania, Philadelphia, PA, USA; 3Anesthesiology and Critical Care, Universityy of Pennsylvanis, Philadelphia, PA, USA
The accuracy and precision of MR susceptometry-based oximetry was investigated theoretically on the basis of an analytical expression for the arbitrarily oriented cylinder, as well as experimentally in phantoms and in vivo in the femoral artery and vein at 3T field strength. Hemoglobin saturation was measured at successive vessel segments, differing in geometry but constant blood oxygen saturation levels, as a means to evaluate measurement consistency. Reproducibility of in vivo HbO2 quantification was on the order of 5% in the femoral vessels and the data indicate that non-circularity, although corrigible, can be ignored even at 30o with tilt correction alone.