Phantom and workflow for validation and quality assurance of musculoskeletal MR intensive-variable biomarkers

Motivation: We seek better validation and QA of musculoskeletal intensive-variable MR biomarkers. Goal(s): We aimed to devise and evaluate a phantom with suitable form factor and composition for practical use in this setting. Approach: “Expected” temperature- and B0-dependent R1 values were calculated from prior data and verified by inversion recovery (IR). Practical QA use cases for hand and knee trials were exemplified using product-sequence 3D variable flip angle (3DVFA) R1measurements on three vendors’ scanners. Results: There was little deviation between “Expected” and IR-measured R1 (rms 3.8%). 3DVFA R1 exhibited bias (mean +23%) which must be subtracted during within-study QA. Impact: This work will improve QA in real-world musculoskeletal clinical trials which use intensive-variable MR biomarkers, and will help validate such biomarkers.