T2 mapping of the heart with high temporal and spatial resolution using a radial double inversion fast spin-echo pulse sequence with view sharing

Background While DE imaging is considered a gold standard in the evaluation of myocardial scar/viability in patients with old MI or cardiomyopathy, a few recent publications demonstrate a higher diagnostic sensitivity of T2weighted techniques in patients with Non-STEMI and myocarditis where changes in T2-weighting are due to inflammation in the myocardium leading to edema (Abdel-Aty H, JACC 53:1194, 2009; Tilak GS, Invest Radiol 43:7, 2008). Thus, recently there has been great interest in measuring T2, the parameter responsible for contrast in T2weighted images (Giri S, JCMR 11:56, 2009; Kim D Magn Reson Med 62:300, 2009). Most proposed methods, however, do not have adequate spatial and temporal resolution for detecting subtle changes in the myocardium T2 or are affected by artifacts caused by motion and flow. Our group developed a Double Inversion Radial Fast Spin Echo (DIR-RADFSE) sequence that yields TE images and T2 maps of the heart, with fewer motion and flow artifacts compared to conventional methods. DIR-RADFSE yields data for 16 perfectly registered TE images (in plane resolution ~ 1.3-1.6 mm). The TE images are used for the voxel-wise generation T2 maps. The high temporal resolution afforded by DIR-RADFSE allows for accurate T2 estimation. The high spatial resolution enables detecting T2 changes in small areas.