Knutsson Linda, Yadav Nirbhay N, Ali Sajad Mohammed, Kamson David Olayinka, Demetriou Eleni, Seidemo Anina, Blair Lindsay, Lin Doris D, Laterra John, VAN Zijl Peter C M
F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, US.
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, US.
ArXiv. 2024 Oct 22:arXiv:2410.17119v1.
Dynamic glucose enhanced (DGE) MRI studies employ chemical exchange saturation transfer (CEST) or spin lock (CESL) to study glucose uptake. Currently, these methods are hampered by low effect size and sensitivity to motion. To overcome this, we propose to utilize exchange-based linewidth (LW) broadening of the direct water saturation (DS) curve of the water saturation spectrum (Z-spectrum) during and after glucose infusion (DS-DGE MRI).
To estimate the glucose-infusion-induced LW changes ( ), Bloch-McConnell simulations were performed for normoglycemia and hyperglycemia in blood, gray matter (GM), white matter (WM), CSF, and malignant tumor tissue. Whole-brain DS-DGE imaging was implemented at 3 tesla using dynamic Z-spectral acquisitions (1.2 s per offset frequency, 38 s per spectrum) and assessed on four brain tumor patients using infusion of 35 g of D-glucose. To assess , a deep learning-based Lorentzian fitting approach was employed on voxel-based DS spectra acquired before, during, and post-infusion. Area-under-the-curve (AUC) images, obtained from the dynamic time curves, were compared qualitatively to perfusion-weighted imaging (PWI).
In simulations, was 1.3%, 0.30%, 0.29/0.34%, 7.5%, and 13% in arterial blood, venous blood, GM/WM, malignant tumor tissue, and CSF, respectively. , was approximately 1% in GM/WM, 5-20% for different tumor types, and 40% in CSF. The resulting DS-DGE AUC maps clearly outlined lesion areas.
DS-DGE MRI is highly promising for assessing D-glucose uptake. Initial results in brain tumor patients show high-quality AUC maps of glucose-induced line broadening and DGE-based lesion enhancement similar and/or complementary to PWI.
动态葡萄糖增强（DGE）磁共振成像（MRI）研究采用化学交换饱和转移（CEST）或自旋锁定（CESL）来研究葡萄糖摄取。目前，这些方法受到效应量低和对运动敏感的限制。为克服这一问题，我们建议在葡萄糖输注期间及之后利用水饱和谱（Z谱）的直接水饱和（DS）曲线基于交换的线宽（LW）展宽（DS-DGE MRI）。
为估计葡萄糖输注引起的LW变化（ ），对血液、灰质（GM）、白质（WM）、脑脊液（CSF）和恶性肿瘤组织中的正常血糖和高血糖情况进行了Bloch-McConnell模拟。在3特斯拉下使用动态Z谱采集（每个偏移频率1.2秒，每个谱38秒）进行全脑DS-DGE成像，并对4名脑肿瘤患者输注35克D-葡萄糖后进行评估。为评估 ，对输注前、输注期间和输注后采集的基于体素的DS谱采用基于深度学习的洛伦兹拟合方法。从动态 时间曲线获得的曲线下面积（AUC）图像与灌注加权成像（PWI）进行定性比较。
在模拟中，动脉血、静脉血、GM/WM、恶性肿瘤组织和CSF中的 分别为1.3%、0.30%、0.29/0.34%、7.5%和13%。 ，GM/WM中约为1%，不同肿瘤类型为5 - 20%，CSF中为40%。所得的DS-DGE AUC图清晰勾勒出病变区域。
DS-DGE MRI在评估D-葡萄糖摄取方面极具前景。脑肿瘤患者的初步结果显示，葡萄糖诱导的线展宽和基于DGE的病变增强的高质量AUC图与PWI相似和/或互补。
