Chris V. Bowen1,2, Nicole A. Pelot1,3
1Institute for Biodiagnostics
(Atlantic), National Research Council, Halifax, NS, Canada; 2Physics
& Atmospheric Science, Dalhousie University, Halifax, NS, Canada; 3Physics
& Atmospheric Science & Electrical Engineering, Dalhousie University,
Halifax, NS, Canada
An MRI-based iron quantification method could significantly advance molecular imaging of drugs and diseases in vivo. We propose obtaining R2 values in the presence of SPIO using phase-cycled inversion recovery bSSFP with a novel on-resonance frequency index selection algorithm. The on-resonance frequency was identified as the smallest R2 value after rejecting the largest residuals voxel-by-voxel. Phantoms were imaged at 3T to produce calibration curves using small flip angles to extend dynamic range. With a 20deg flip, quantification was achieved up to 100gFe/mL. This technique has potential to significantly impact the use of MRI for pre-clinical studies using targeted molecular imaging.