Myocardial T*2 mapping free of distortion using susceptibility-weighted fast spin-echo imaging: A feasibility study at 1.5 T and 3.0 T

Abstract

This study demonstrates the feasibility of applying free-breathing, cardiac-gated, susceptibility-weighted fast spin-echo imaging together with black blood preparation and navigator-gated respiratory motion compensation for anatomically accurate T*2 mapping of the heart. First, T*2 maps are presented for oil phantoms without and with respiratory motion emulation (T*2 = (22.1 ± 1.7) ms at 1.5 T and T*2 = (22.65 ± 0.89) ms at 3.0 T). T*2 relaxometry of a ferrofluid revealed relaxivities of R*2 = (477.9 ± 17) mM-1s-1 and R*2 = (449.6 ± 13) mM-1s-1 for UFLARE and multiecho gradient-echo imaging at 1.5 T. For inferoseptal myocardial regions mean T*2 values of 29.9 ± 6.6 ms (1.5 T) and 22.3 ± 4.8 ms (3.0 T) were estimated. For posterior myocardial areas close to the vena cava T*2-values of 24.0 ± 6.4 ms (1.5 T) and 15.4 ± 1.8 ms (3.0 T) were observed. The merits and limitations of the proposed approach are discussed and its implications for cardiac and vascular T*2-mapping are considered. © 2009 Wiley-Liss, Inc.