Developing a medical device-grade T 2 phantom optimized for myocardial T 2 mapping by cardiovascular magnetic resonance

A long T relaxation time can reflect oedema, and myocardial inflammation when combined with increased plasma troponin levels. Cardiovascular magnetic resonance (CMR) T mapping therefore has potential to provide a key diagnostic and prognostic biomarkers. However, T varies by scanner, software, and sequence, highlighting the need for standardization and for a quality assurance system for T mapping in CMR. To fabricate and assess a phantom dedicated to the quality assurance of T mapping in CMR. A T mapping phantom was manufactured to contain 9 T and T (T |T ) tubes to mimic clinically relevant native and post-contrast T in myocardium across the health to inflammation spectrum (i.e., 43-74 ms) and across both field strengths (1.5 and 3 T). We evaluated the phantom's structural integrity, B and B uniformity using field maps, and temperature dependence. Baseline reference T |T were measured using inversion recovery gradient echo and single-echo spin echo (SE) sequences respectively, both with long repetition times (10 s). Long-term reproducibility of T |T was determined by repeated T |T mapping of the phantom at baseline and at 12 months. The phantom embodies 9 internal agarose-containing T |T tubes doped with nickel di-chloride (NiCl ) as the paramagnetic relaxation modifier to cover the clinically relevant spectrum of myocardial T . The tubes are surrounded by an agarose-gel matrix which is doped with NiCl and packed with high-density polyethylene (HDPE) beads. All tubes at both field strengths, showed measurement errors up to ≤ 7.2 ms [