Watanabe H, Ishihara Y, Okamoto K, Oshio K, Kanamatsu T, Tsukada Y
Toshiba Research and Development Center, Kawasaki, 210-8582, Japan.
J Magn Reson. 1998 Oct;134(2):214-22. doi: 10.1006/jmre.1998.1503.
The 3D localized 13C spectroscopy methods LINEPT and LODEPT, which are modifications of INEPT and DEPT, are proposed. As long as a 13C inversion pulse (180-degree pulse) is applied at 1/(4J) before the proton echo time in LINEPT and a 13C excitation pulse (90-degree pulse) is applied at 1/(2J) before the proton echo time in LODEPT, the proton echo time can be set to any value longer than 1/(2J) in LINEPT and longer than 1/J in LODEPT. As a result, the proton and the 13C pulses can be applied separately and these proton pulses can be made slice-selective pulses. These localization features of LINEPT and LODEPT were evaluated using a phantom consisting of a cylinder filled with ethanol placed inside another cylinder filled with oil, and localized ethanol spectra could be obtained. In vivo 3D localized 13C spectra from the brain of a monkey could be obtained using decoupled LINEPT, and glutamate C-4 appeared directly after the administration of glucose C-1, followed by the appearance of glutamate C-2, C-3 and glutamine C-2, C-3, C-4.
提出了对INEPT和DEPT进行改进的3D局部13C光谱方法LINEPT和LODEPT。只要在LINEPT中质子回波时间前1/(4J)处施加13C反转脉冲（180°脉冲），在LODEPT中质子回波时间前1/(2J)处施加13C激发脉冲，LINEPT中的质子回波时间就可以设置为大于1/(2J)的任意值，LODEPT中的质子回波时间可以设置为大于1/J的任意值。结果，质子脉冲和13C脉冲可以分别施加，并且这些质子脉冲可以制成切片选择脉冲。使用由置于装满油的另一个圆柱体内的装满乙醇的圆柱体组成的模型对LINEPT和LODEPT的这些定位特性进行了评估，并且可以获得局部乙醇光谱。使用去耦的LINEPT可以从猴子大脑中获得体内3D局部13C光谱，在给予葡萄糖C-1后谷氨酸C-4直接出现，随后是谷氨酸C-2、C-3以及谷氨酰胺C-2、C-3、C-4的出现。
