Ian D. Driver1, Samuel J. Wharton1, Paula L. Croal1, Richard W. Bowtell1, Susan T. Francis1, Penelope A. Gowland1
1Sir Peter Mansfield Magnetic Resonance Centre, University of Nottingham, Nottingham, United Kingdom
The measurement of venous blood oxygenation (Yv) is important in cases where oxygen extraction fraction (OEF) may be perturbed. We assess phase-based methods for measuring Yv, either using intravascular phase of a large vein (the superior sagittal sinus in our case), or by comparing the phase distributions local to a vessel, as perturbed by hyperoxia. We measured similar Yv values using both approaches, although the hyperoxia-based method is suitable for small veins and independent of their orientation, providing localised Yv measurements. Some evidence for spatial heterogeneity in Yv was found using this method.