Blood T1 measurements using slice-interleaved T1 mapping (STONE) sequence

Background Slice interleaved T1 (STONE) mapping sequence was recently proposed to take advantage of increased recovery time of spins to improve accuracy and precision of native myocardial T1 values. In this sequence, a nonselective inversion pulse is followed by acquisition of the data for different slices. Therefore, blood pool may experience different recovery time at different slice location due to mixing effect and rapid blood flow movement. This may impact ECV measurements using STONE based T1 mapping sequence. While, a short T1 of blood after contrast allows full recovery, long native T1 of blood pool may cause errors in T1 measurements, which will manifest as low reproducibility and variations across different locations. Therefore, we sought to assess the native blood T1 values measured in the right ventricle (RV) and left ventricle (LV) by studying the reproducibility of T1 measurements at different locations and slices.