Motivation: Non-invasive measurement of bone marrow fat content, which helps characterize and monitor hematologic disease processes, is a major unmet need. Chemical-shift-encoded (CSE) MRI with 2D flip-angle modulation (FAM) offers a motion-robust alternative to 3D-CSE MRI for PDFF measurement. Goal(s): To compare bone marrow PDFF measured using FAM-CSE and 3D-CSE MRI. Approach: Single-center retrospective study of patients who underwent both FAM-CSE and 3D-CSE MRI; vertebral body PDFF measured using both techniques were compared for linearity and bias. Results: Bone marrow PDFF measured using FAM-CSE and 3D-CSE MRI demonstrate strong linearity, but also non-negligible relative bias compared to each other. Impact: FAM-based CSE MRI is a promising tool for motion-robust measurement of bone marrow PDFF, which may help characterization of many hematologic disease processes. However, it requires further validation and addressing potential sources of bias.
Souza et al. (Tue,) studied this question.