Characterization of a Pseudo-Tissue Liver Flow Phantom for Use in Magnetic Resonance Elastography Validation Experiments

Motivation: MRE is utilized to assess tissue stiffness in vivo, however, robust validation in tissue-mimicking phantoms is needed. Goal(s): Create hydrogel liver phantoms of varying stiffness, characterize them with MRE and compare MRE with a mechanical reference standard. Utilize pulsatile flow to mimic cardiac motion. Approach: Flow phantoms of varying stiffness were created. Stiffness from mechanical test was compared to MRE. Cardiac tagging visualized motion inside each phantom. Results: MRE shear stiffness showed agreement with indenter stiffness and cardiac motion decreased with stiffness. Impact: Advances in MRE have led to its increasing use to determine tissue stiffness in vivo, however, robust validation in tissue mimicking phantoms has yet to be achieved. The proposed methodology may help to assess the quantitative performance of MRE.