Matsumoto Shunsuke, Okuda Shigeo, Yamada Yoshitake, Suzuki Tatsuya, Tanimoto Akihiro, Nozaki Atsushi, Jinzaki Masahiro
Department of Radiology, Keio University School of Medicine, 35 Shinanomachi, Shinjyuku-ku, Tokyo, 160-8582, Japan.
MR Applications and Workflow, GE Healthcare Japan, 4-7-127, Asahigaoka, Hino-shi, Tokyo, Japan.
Heart Vessels. 2019 Nov;34(11):1889-1894. doi: 10.1007/s00380-019-01401-5. Epub 2019 Apr 11.
Myocardial T1 mapping is clinically valuable for assessing the myocardium, and modified look-locker inversion-recovery (MOLLI) approaches have been commonly used for measuring myocardial T1 values. To date, several other sequences have been developed for measuring myocardial T1 values, and saturation-recovery-based sequences have been shown to be less dependent on various factors, such as T2 times and magnetization transfer, than inversion-recovery techniques. Systematic differences in T1 values between different sequences have been reported; therefore, definition of the normal range of native T1 values is required before clinical usage can begin. The purpose of this study was to evaluate the reference range and sex dependency of native T1 values in the myocardium measured using one such saturation-recovery sequence, i.e., saturation method using adaptive recovery times for cardiac T1 mapping (SMART1Map). Myocardial T1 values were compared between SMART1Map and MOLLI in 24 young healthy volunteers at 1.5 T and 3 T, and differences in the T1 values between the sexes were assessed. The mean native T1 values in the myocardium were significantly longer with SMART1Map than MOLLI [1530.4 ± 49.2 vs 1222.1 ± 48.9 ms at 3 T (p < 0.001) and 1227.3 ± 41.9 ms vs 1014.8 ± 49.4 ms at 1.5 T (p < 0.001)]. A significant difference between the sexes was observed in the T1 values obtained using each sequence, excluding SMART1Map at 3 T. The SMART1Map has a potential advantage to overcome the shortcoming of MOLLI, which underestimates T1 values; however, the sex-dependent difference remains obscure using SMART1Map.
心肌T1 mapping对于评估心肌具有临床价值，改良的Look-Locker反转恢复（MOLLI）方法已被广泛用于测量心肌T1值。迄今为止，已经开发了其他几种用于测量心肌T1值的序列，并且基于饱和恢复的序列已被证明比反转恢复技术对诸如T2时间和磁化传递等各种因素的依赖性更小。不同序列之间T1值的系统差异已有报道；因此，在临床应用开始之前，需要定义天然T1值的正常范围。本研究的目的是评估使用一种这样的饱和恢复序列（即用于心脏T1 mapping的自适应恢复时间饱和方法（SMART1Map））测量的心肌天然T1值的参考范围和性别依赖性。在24名年轻健康志愿者中，于1.5T和3T时比较了SMART1Map和MOLLI之间的心肌T1值，并评估了两性之间T1值的差异。心肌中的平均天然T1值在SMART1Map下比MOLLI显著更长[3T时为1530.4±49.2 vs 1222.1±48.9ms（p<0.001），1.5T时为1227.3±41.9ms vs 1014.8±49.4ms（p<0.001）]。在使用每个序列获得的T1值中观察到两性之间存在显著差异，但3T时的SMART1Map除外。SMART1Map具有克服MOLLI低估T1值这一缺点的潜在优势；然而，使用SMART1Map时性别依赖性差异仍然不明确。
