Liver T1ρ MRI measurement in healthy human subjects at 3 T: a preliminary study with a two-dimensional fast-field echo sequence
Liver T1ρ MRI measurement in healthy human subjects at 3 T: a preliminary study with a two-dimensional fast-field echo sequence
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DOI：
10.1259/bjr/98745548
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发表时间：
2012-09-01
影响因子：
2.6
通讯作者：
Wang, Y-X J.
中科院分区：
文献类型：
--
作者：
Deng, M.;Zhao, F.;Wang, Y-X J.
目的：本研究旨在探讨肝脏T-1 rho MRI的技术可行性，并确定临床3 T健康受试者肝脏T-1 rho的正常范围。方法：15名健康志愿者。选择三个有代表性的轴向切片切穿上、中、下肝脏。在二维快场回波序列中实现旋转回波自旋锁定脉冲。自旋锁频率为500 Hz，自旋锁时间为1、10、20、30、40和50 ms用于T-1 rho映射。这些图像是在屏气期间逐片采集的。感兴趣区域（ROI；n=5）手动放置在肝实质区域的每个切片上，不包括伪影和血管。这些 ROI (n=15) 的平均值被视为受试者的肝脏 T-1 rho 值。六名受试者在禁食状态下接受一次扫描；餐后 2 小时对 6 名受试者进行一次扫描；三名受试者在禁食状态下接受两次扫描；七名受试者在餐后 2 小时接受两次扫描。结果：当两名读者测量相同的 10 个数据集时，读者间的再现性（ICC：组内相关系数）为 0.955。对 10 名受试者进行两次扫描，扫描-再扫描重现性的 ICC 为 0.764。肝脏T-1 rho值在空腹状态（43.08+/-1.41ms）和餐后状态（42.97+/-2.38ms，p=0.867）没有显着差异。汇总本研究中的所有 32 次扫描，正常肝脏 T-1 rho 值范围为 38.6 至 48.3 ms（平均 43.0 ms，中位 42.6 ms）。 结论：在 3 T 下获得人类受试者一致的肝脏 T-1 rho 测量是可行的。
Objectives: The aim of this study was to explore the technical feasibility of T-1 rho MRI for the liver, and to determine the normal range of liver T-1 rho in healthy subjects at clinical 3 T.Methods: There were 15 healthy volunteers. Three representative axial slices were selected to cut through the upper, middle and lower liver. A rotary echo spin-lock pulse was implemented in a two-dimensional fast-field echo sequence. Spin-lock frequency was 500 Hz, and the spin-lock times of 1, 10, 20, 30, 40 and 50 ms were used for T-1 rho mapping. The images were acquired slice by slice during breath-holding. Regions of interest (ROIs; n=5) were manually placed on each slice of the liver parenchyma region, excluding artefacts and vessels. The mean value of these ROIs (n=15) was regarded as the liver T-1 rho value for the subject. Six subjects were scanned once at fasting status; six subjects were scanned once 2 h post meal; three subjects were scanned twice at fasting status; and seven subjects were scanned twice 2 h post meal.Results: When two readers measured the same 10 data sets, the interreader reproducibility (ICC: intraclass correlation coefficient) was 0.955. With the 10 subjects scanned twice, the ICC for scan-rescan reproducibility was 0.764. There was no significant difference for the liver T-1 rho value at the fasting status (43.08 +/- 1.41 ms) and post-meal status (42.97 +/- 2.38 ms, p=0.867). Pooling together all the 32 scans in this study, the normal liver T-1 rho value ranged from 38.6 to 48.3 ms (mean 43.0 ms, median 42.6 ms).Conclusion: It is feasible to obtain consistent liver T-1 rho measurement for human subjects at 3 T.