Quantitative Phantom for Multi-Modality Magnetic Resonance Imaging and Computed Tomography Measurements of Steatotic Tissue

The overall goal of this proposal is to design, develop, and test a multi-modality imaging test object (“phantom”) for quality assurance (QA) of tissue fat concentration measurements by magnetic resonance imaging (MRI) and computed tomography (CT). This Phase II application proposes to expand the clinical applicability of the Phase I CT/MRI Fat Phantom prototype by: 1) developing gels that mimic the CT and MRI properties of fat-infiltrated skeletal muscle, augmenting the liver-mimicking gels that were developed during Phase I; 2) modularizing the phantom housing design to enable exchange of the tissue mimicking components by the end user; and 3) evaluating the phantom shelf-life. Specifically, the proposed phantom must mimic the relationship between CT attenuation and fat-fraction observed in human skeletal muscle and liver and must replicate the critical MRI properties of these tissues, including the MRI spectrum and relaxation properties. A phantom that could serve as a reference standard for both MRI and CT would facilitate harmonization, ie: direct comparison of data acquired using these two prevalent imaging modalities. Cross-modality consistency is needed in clinical practice for longitudinal monitoring of patients who undergo MRI and CT over time, on multiple vendor platforms, and for multi-site research studies.