T2 measurement of the human myocardium using a T2-prepared transient-state TrueFISP sequence
T2 measurement of the human myocardium using a T2-prepared transient-state TrueFISP sequence
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DOI：
10.1002/mrm.21208
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发表时间：
2007-05-01
影响因子：
3.3
通讯作者：
Poncelet, Brigitte P.
中科院分区：
文献类型：
--
作者：
Huang, Teng-Yi;Liu, Yi-Jui;Poncelet, Brigitte P.
提出了一种适用于心肌大胆对比成像的快速运动不敏感技术。这种名为TrueFISP的方法结合了T-2磁化准备和稳态自由进动(SSFP)成像，用于健康志愿者心肌的T-2弛豫标测。T-2的对比度噪声比(CNR)通过使用暂态TrueFISP读出和采用线性相位编码的半傅立叶读出进行了优化。在一次心跳内获得单层心肌T_2加权像，在5~7岁的S中获得心肌的单层T_2图。采用呼吸导航仪的方法进行连续测量和信号平均，受试者自由呼吸。12名健康志愿者测得的平均T-2松弛时间为54±5.7ms。T-2值在整个心肌的区域差异为7%。在覆盖左室壁0.5毫升的跨壁区域，连续T-2测量的时间变异在信号平均(激发次数(NEX)=1)下为3.6%，在信号平均(NEX=10)下为1.7%。根据我们的初步结果，T-2-TrueFISP法有望为心肌BOLD造影的临床应用提供一种可靠而敏感的工具。
fast and motion-insensitive technique suitable for myocardial BOLD contrast imaging is presented. The method, termed TrueFISP, combines T-2 magnetization preparation with steadystate free precession (SSFP) imaging for T-2 relaxation mapping of the myocardium in healthy volunteers. The T-2 contrast-to-noise ratio (CNR) was optimized with the use of transient-state TrueFISP readout and half-Fourier readout with linear phase encoding. Single-slice myocardial T-2-weighted image was obtained within one heartbeat, and a single slice T-2 map of the myocardium was obtained in under 5-7 s. A respiratory navigator-gating method was incorporated for serial measurements and signal averaging, with the subjects breathing freely. The mean myocardial T-2 relaxation time measured in 12 healthy volunteers was 54 +/- 5.7 ms. Regional variations of T-2 values across the myocardium were 7%. Temporal variations across serial T-2 measurements in a transmural region covering similar to 0.5 cc of the left ventricular (LV) wall were 3.6% without signal averaging (number of excitations (NEX) = 1) and 1.7% with signal averaging (NEX = 10). According to our preliminary results, the T-2-TrueFISP method is expected to provide a robust and sensitive tool for clinical application of myocardial BOLD contrast imaging.