In vivo lactate editing with simultaneous detection of choline, creatine, NAA, and lipid singlets at 1.5 T using PRESS excitation with applications to the study of brain and head and neck tumors
In vivo lactate editing with simultaneous detection of choline, creatine, NAA, and lipid singlets at 1.5 T using PRESS excitation with applications to the study of brain and head and neck tumors
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DOI：
10.1006/jmre.1998.1458
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发表时间：
1998-08-01
影响因子：
2.2
通讯作者：
Vigneron, DB
中科院分区：
文献类型：
--
作者：
Star-Lack, J;Spielman, D;Vigneron, DB
介绍了用于 PRESS 磁共振波谱定位序列的两种与 T2 无关的 J 差乳酸编辑方案。该技术允许同时采集乳酸双峰 (1.3 ppm) 和含有胆碱 (3.2 ppm) 的编辑单峰，利用甲基双峰同相强度对初始激发后施加到其耦合伙伴的两个反转 (BASING) 脉冲之间的时间间隔的依赖性。编辑方法 1 允许回波时间 TE = n/J (n = 1, 2, 3,...)，改变两个周期中每个周期的 BASING 载波频率，以便对于一个周期，四重奏被反转，而对于另一个周期，四重奏不受影响。方法 2 也提供水抑制，允许通过在循环之间交替分隔反转脉冲的时间间隔来编辑 TE > 1/J。实验结果是使用 Shinnar Le-Roux 设计的最大反相脉冲在 1.5 T 下获得的，滤波器过渡带宽为 55 Hz。光谱是从人体模型和人脑和颈部的体内获得的。在一项颈部肌肉研究中，部分通过使用新型相位正则化算法实现的脂质抑制因子经测量超过 10(3)。从原发性大脑和转移性颈部肿瘤获得的光谱表明存在与异常光谱模式一致的乳酸和胆碱信号。从理论上和实验上分析了这些方法的优点和局限性，并讨论了结果的意义。 (C) 1998 年学术出版社。
Two T2-independent J-difference lactate editing schemes for the PRESS magnetic resonance spectroscopy localization sequence are introduced. The techniques, which allow for simultaneous acquisition of the lactate doublet (1.3 ppm) and edited singlets upheld of and including choline (3.2 ppm), exploit the dependence of the in-phase intensity of the methyl doublet upon the time interval separating two inversion (BASING) pulses applied to its coupling partner after initial excitation. Editing method 1, which allows for echo times TE = n/J (n = 1, 2, 3,...), alters the BASING carrier frequency for each of two cycles so that, for one cycle, the quartet is inverted, whereas, for the other cycle, the quartet is unaffected. Method 2, which also provides water suppression, allows for editing for TE > 1/J by alternating, between cycles, the time interval separating the inversion pulses. Experimental results were obtained at 1.5 T using a Shinnar Le-Roux-designed maximum phase inversion pulse with a filter transition bandwidth of 55 Hz. Spectra were acquired from phantoms and in vivo from the human brain and neck. In a neck muscle study, the lipid suppression factor, achieved partly through the use of a novel phase regularization algorithm, was measured to be over 10(3). Spectra acquired from a primary brain and a metastatic neck tumor demonstrated the presence of lactate and choline signals consistent with abnormal spectral patterns. The advantages and limitations of the methods are analyzed theoretically and experimentally, and significance of the results is discussed. (C) 1998 Academic Press.