Free-breathing slice-interleaved myocardial T2 mapping with slice-selective T2 magnetization preparation.
Free-breathing slice-interleaved myocardial T2 mapping with slice-selective T2 magnetization preparation.
复制标题
DOI：
10.1002/mrm.25907
复制
发表时间：
2016-08
影响因子：
3.3
通讯作者：
Nezafat R
中科院分区：
文献类型：
--
作者：
Basha TA;Bellm S;Roujol S;Kato S;Nezafat R
通过提出一种新的切片选择性 T2 磁化准备 (T2prep) 序列来开发和评估自由呼吸切片交错 T2 映射序列，该序列允许在后续心跳中对不同切片进行交错数据采集。我们通过在传统的单切片 T2prep 序列中添加切片选择性梯度，开发了用于心肌 T2 映射的切片选择性 T2prep。在此序列中，在 5 个连续心跳期间采集 5 个切片，每个切片都使用切片选择性 T2prep。使用不同的 T2prep 回波时间将该方案重复四次。我们在 10 名健康受试者中使用体模实验和体内成像，比较了所提出的切片交错 T2 映射序列和传统的单切片 T2 映射序列在准确性、精确性和可重复性方面的性能。我们还评估了 28 名心血管疾病患者所提出的序列的可行性，并对图谱的质量进行了主观评分。此外，我们通过比较收缩末期与舒张中期期间获得的 T2 测量值来研究平面运动的影响。使用切片交错 T2 映射序列的 T2 测量与自旋回波 (r2 = 0.88) 和单切片 T2 映射序列 (r2 = 0.98) 相关。平均心肌 T2 值在切片交错 (48 ms) 和单切片 (51 ms) T2 映射序列之间相关。 81% 的患者 T2 图质量主观评分为良好至优秀。收缩末期与舒张中期之间的 T2 测量值没有差异。所提出的自由呼吸切片交错 T2 映射序列允许在 20 次心跳中对 5 个左心室切片进行 T2 测量，其重现性和精度与单切片 T2 映射序列相似，但采集时间减少 4 倍。
To develop and evaluate a free-breathing slice-interleaved T2 mapping sequence by proposing a new slice-selective T2 magnetization preparation (T2prep) sequence that allows interleaved data acquisition for different slices in subsequent heart beats. We developed a slice-selective T2prep for myocardial T2 mapping by adding slice-selective gradients to conventional single-slice T2prep sequence. In this sequence, 5 slices are acquired during 5 consecutive heartbeats, each using a slice selective T2prep. The scheme is repeated four times using different T2prep echo times. We compared the performance of the proposed slice-interleaved T2 mapping sequence and the conventional single-slice T2 mapping sequence in term of accuracy, precision and reproducibility using phantom experiments and in-vivo imaging in 10 healthy subjects. We also evaluated the feasibility of the proposed sequence in 28 patients with cardiovascular disease and the quality of the maps was subjectively scored. Furthermore, we investigated the impact of through-plane motion by comparing T2 measurements acquired during end-systole vs. mid-diastole. T2 measurements using slice-interleaved T2 mapping sequence were correlated with spin-echo (r2 = 0.88) and single-slice T2 mapping sequence (r2 = 0.98). The mean myocardial T2 values were correlated between slice-interleaved (48 ms) and single-slice (51 ms) T2 mapping sequences. Subjective scores of T2 map quality were good to excellent in 81% of the maps in patients. There was no difference in T2 measurements between end-systole vs. mid-diastole. The proposed free-breathing slice-interleaved T2 mapping sequence allows T2 measurements of 5 left ventricular slices in 20 heartbeats with similar reproducibility and precision as the single-slice T2 mapping sequence but with 4-fold reduction in acquisition time.