Zu Zhongliang, Spear John, Li Hua, Xu Junzhong, Gore John C
Vanderbilt University Institute of Imaging Science, Nashville, TN; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN.
Vanderbilt University Institute of Imaging Science, Nashville, TN; Deparment of Physics and Astronomy, Vanderbilt University, Nashville, TN.
Magn Reson Imaging. 2014 Nov;32(9):1078-84. doi: 10.1016/j.mri.2014.06.002. Epub 2014 Jun 21.
The regional uptake of glucose in rat brain in vivo was measured at high resolution using spin-lock magnetic resonance imaging after infusion of the glucose analogue 2-deoxy-d-glucose (2DG). Previous studies of glucose metabolism have used 13C-labeled 2DG and NMR spectroscopy, 18F-labeled fluorodeoxyglucose (FDG) and PET, or chemical exchange saturation transfer (CEST) MRI, all of which have practical limitations. Our goal was to explore the ability of spin-lock sequences to detect specific chemically-exchanging species in vivo and to compare the effects of 2DG in brain tissue on CEST images.
Numerical simulations of R1p and CEST contrasts for a variety of sample parameters were performed to evaluate the potential specificity of each method for detecting the exchange contributions of 2DG. Experimental measurements were made in tissue phantoms and in rat brain in vivo which demonstrated the ability of spin-lock sequences for detecting 2DG.
R1p contrast acquired with appropriate spin-lock sequences can isolate the contribution of exchanging protons in 2DG in vivo and appears to have better sensitivity and more specificity to 2DG-water exchange effects than CEST.
Spin-lock imaging provides a novel approach to the detection and measurement of glucose uptake in brain in vivo.
在注入葡萄糖类似物2-脱氧-D-葡萄糖（2DG）后，使用自旋锁定磁共振成像在高分辨率下测量大鼠脑内葡萄糖的区域摄取。先前关于葡萄糖代谢的研究使用了13C标记的2DG和核磁共振波谱、18F标记的氟脱氧葡萄糖（FDG）和正电子发射断层扫描（PET），或化学交换饱和转移（CEST）磁共振成像，所有这些方法都存在实际局限性。我们的目标是探索自旋锁定序列在体内检测特定化学交换物质的能力，并比较脑组织中2DG对CEST图像的影响。
对各种样本参数进行R1p和CEST对比的数值模拟，以评估每种方法检测2DG交换贡献的潜在特异性。在组织模型和大鼠脑内进行了实验测量，证明了自旋锁定序列检测2DG的能力。
使用适当的自旋锁定序列获得的R1p对比可以分离体内2DG中交换质子的贡献，并且似乎对2DG-水交换效应比CEST具有更好的灵敏度和更高的特异性。
自旋锁定成像为体内检测和测量脑内葡萄糖摄取提供了一种新方法。
