Edden Richard A E, Barker Peter B
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Magn Reson Med. 2007 Dec;58(6):1276-82. doi: 10.1002/mrm.21383.
The MEGA-PRESS-IVS method has been developed, which combines MEGA (a frequency-selective editing technique) editing with the point-resolved spectroscopy sequence (PRESS) and inner volume saturation (IVS) localization, reducing the deleterious effects of spatial variation in coupling evolution. The IVS method has been previously described for improved efficiency of lactate detection. The current study demonstrates that the combination of MEGA-PRESS with IVS results in increased sensitivity for edited single-voxel measurements of glutamate and gamma-aminobutyric acid (GABA). A four-compartment model of coupling evolution is investigated through simple product operators and full spin-system simulations and the predicted pattern of signal evolution is demonstrated through MEGA-PRESS-MRSI. MEGA-PRESS-IVS is then compared to MEGA-PRESS in a phantom and an average signal increase of 24% is demonstrated in five healthy volunteers.
已开发出MEGA-PRESS-IVS方法，该方法将MEGA（一种频率选择性编辑技术）编辑与点分辨光谱序列（PRESS）和内部容积饱和（IVS）定位相结合，减少了耦合演化中空间变化的有害影响。IVS方法先前已被描述用于提高乳酸检测效率。当前研究表明，MEGA-PRESS与IVS相结合可提高对谷氨酸和γ-氨基丁酸（GABA）编辑的单体素测量的灵敏度。通过简单的乘积算符和全自旋系统模拟研究了耦合演化的四室模型，并通过MEGA-PRESS-MRSI展示了预测的信号演化模式。然后在体模中将MEGA-PRESS-IVS与MEGA-PRESS进行比较，在五名健康志愿者中显示平均信号增加了24%。
