Triple repetition time saturation transfer (TRiST) 31P spectroscopy for measuring human creatine kinase reaction kinetics.
Triple repetition time saturation transfer (TRiST) 31P spectroscopy for measuring human creatine kinase reaction kinetics.
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DOI：
10.1002/mrm.22347
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发表时间：
2010-06
影响因子：
3.3
通讯作者：
Bottomley, Paul A.
中科院分区：
文献类型：
--
作者：
Schar, Michael;El-Sharkawy, AbdEl-Monem M.;Weiss, Robert G.;Bottomley, Paul A.
关键词：
此前已在 1.5T 下进行了人心脏磷 MR 饱和转移 (ST) 实验，以量化肌酸激酶 (CK) 前向速率常数 (kf)。此类实验可以受益于 3T 下信噪比和光谱分辨率的提高。在 1.5T 时，采用四角度 ST 方法，采用低角度绝热脉冲和表面线圈。然而，由于带宽限制、功率要求、功率沉积和脉冲内自旋-自旋衰减，低角度绝热脉冲在 1.5T 以上可能会出现问题。对于局部代谢物自旋晶格弛豫时间 (T1) 测量，最近引入了采用绝热半通道脉冲的双重复时间 (2TR) 方法来解决 3T 下的这些问题。由于 ST 实验需要在一个反应部分饱和时进行 T1 测量，因此我们采用 2TR 方法，使用三重重复时间 ST (TRiST) 方法来测量 kf。还提出了一种新的脉冲饱和方案，该方案降低了对静磁场不均匀性的敏感性并与心脏触发兼容。 TRiST 的 kf 测量值在人体小腿肌肉中与传统 ST 进行了验证，结果一致在 3% 以内。人体小腿 (n=6)、胸肌和心脏 (n=8) CK kf 的第一个 3T TRiST 测量值分别为：0.26±0.04s−1、0.23±0.03s−1 和 0.32±0.07s−1，与之前的 1.5T 值一致。
Human cardiac phosphorus MR saturation transfer (ST) experiments to quantify creatine kinase (CK) forward rate constants (kf) have previously been performed at 1.5T. Such experiments could benefit from increased signal-to-noise ratio and spectral resolution at 3T. At 1.5T, the four-angle ST method was applied with low-angle adiabatic pulses and surface coils. However, low-angle adiabatic pulses are potentially problematic above 1.5T due to bandwidth limitations, power requirements, power deposition and intra-pulse spin-spin decay. For localized metabolite spin-lattice relaxation time (T1) measurements, a dual repetition time (2TR) approach with adiabatic half-passage pulses was recently introduced to solve these problems at 3T. Because the ST experiment requires a T1 measurement performed while one reacting moiety is saturated, we adapt the 2TR approach to measure kf using a Triple Repetition time ST (TRiST) method. A new pulsed saturation scheme with reduced sensitivity to static magnetic field inhomogeneity and compatibility with cardiac triggering is also presented. TRiST measurements of kf are validated in human calf muscle against conventional ST, and found to agree within 3%. The first 3T TRiST measurements of CK kf in the human calf (n=6), chest muscle and heart (n=8) are: 0.26±0.04s−1, 0.23±0.03s−1 and 0.32±0.07s−1, respectively, consistent with prior 1.5T values.
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影响因子：
15.9
作者：
Lebon, V;Dufour, S;Shulman, GI
通讯作者：
Shulman, GI
影响因子：
3.3
作者：
Goudemant, JF;Francaux, M;Sturbois, X
通讯作者：
Sturbois, X
影响因子：
3.3
作者：
Shivu, Ganesh Nallur;Abozguia, Khalid;Frenneaux, Michael
通讯作者：
Frenneaux, Michael
影响因子：
4.4
作者：
FORSEN, S;HOFFMAN, RA
通讯作者：
HOFFMAN, RA
DOI：
10.1152/ajpendo.2000.279.2.e333
发表时间：
2000-08-01
影响因子：
5.1
作者：
Horská, A;Fishbein, KW;Spencer, RGS
通讯作者：
Spencer, RGS