Observation and correction of transient cavitation-induced PRFS thermometry artifacts during radiofrequency ablation, using simultaneous Ultrasound/MR imaging

Abstract

RFA induces dynamic changes in magnetic bulk susceptibility in biological tissue, resulting in large and spatially dependent errors of phase-subtraction-only PRFS MRT and unexploitable thermal dose maps. These thermometry artifacts were strongly correlated with the appearance of transient cavitation. A first-order dynamic model of susceptibility provided a useful method for minimizing these artifacts in phantom and ex vivo experiments.