Shan Yi, Wang Zhe, Song Shuangshuang, Xue Qiaoyi, Ge Qi, Yang Hongwei, Cui Bixiao, Zhang Miao, Zhou Yun, Lu Jie
Department of Radiology and Nuclear Medicine, Xuanwu Hospital, Capital Medical University, Beijing, China.
Beijing Key Laboratory of Magnetic Resonance Imaging and Brain Informatics, Beijing, China.
Front Neurosci. 2022 Mar 2;16:824152. doi: 10.3389/fnins.2022.824152. eCollection 2022.
Integrated positron emission tomography (PET)/magnetic resonance imaging (MRI) could simultaneously obtain both functional MRI (fMRI) and F-fluorodeoxyglucose (FDG) PET and thus provide multiparametric information for the analysis of brain metabolism. In this study, we aimed to, for the first time, investigate the interplay of simultaneous fMRI and FDG PET scan using a randomized self-control protocol. In total, 24 healthy volunteers underwent PET/MRI scan for 30-40 min after the injection of FDG. A 22-min brain scan was separated into MRI-off mode (without fMRI pulsing) and MRI-on mode (with fMRI pulsing), with each one lasting for 11 min. We calculated the voxel-wise fMRI metrics (regional homogeneity, amplitude of low-frequency fluctuations, fractional amplitude of low-frequency fluctuations, and degree centrality), resting networks, relative standardized uptake value ratios (SUVr), SUVr slope, and regional cerebral metabolic rate of glucose (rCMRGlu) maps. Paired two-sample -tests were applied to assess the statistical differences between SUVr, SUVr slope, correlation coefficients of fMRI metrics, and rCMRGlu between MRI-off and MRI-on modes, respectively. The voxel-wise whole-brain SUVr revealed no statistical difference ( > 0.05), while the SUVr slope was significantly elevated in sensorimotor, dorsal attention, ventral attention, control, default, and auditory networks ( < 0.05) during fMRI scan. The task-based group independent-component analysis revealed that the most active network components derived from the combined MRI-off and MRI-on static PET images were frontal pole, superior frontal gyrus, middle temporal gyrus, and occipital pole. High correlation coefficients were found among fMRI metrics with rCMRGlu in both MRI-off and MRI-on mode ( < 0.05). Our results systematically evaluated the impact of simultaneous fMRI scan on the quantification of human brain metabolism from an integrated PET/MRI system.
集成正电子发射断层扫描（PET）/磁共振成像（MRI）能够同时获取功能磁共振成像（fMRI）和F-氟脱氧葡萄糖（FDG）PET，从而为脑代谢分析提供多参数信息。在本研究中，我们旨在首次使用随机自我对照方案研究同步fMRI和FDG PET扫描之间的相互作用。总共24名健康志愿者在注射FDG后接受了30 - 40分钟的PET/MRI扫描。一次22分钟的脑部扫描被分为MRI关闭模式（无fMRI脉冲）和MRI开启模式（有fMRI脉冲），每种模式持续11分钟。我们计算了体素级的fMRI指标（局部一致性、低频波动幅度、低频波动分数幅度和中心度）、静息网络、相对标准化摄取值比率（SUVr）、SUVr斜率以及局部脑葡萄糖代谢率（rCMRGlu）图。分别应用配对双样本t检验来评估SUVr、SUVr斜率、fMRI指标的相关系数以及MRI关闭和开启模式之间rCMRGlu的统计差异。体素级全脑SUVr无统计学差异（P > 0.05），而在fMRI扫描期间，感觉运动、背侧注意、腹侧注意、控制、默认和听觉网络中的SUVr斜率显著升高（P < 0.05）。基于任务的组独立成分分析显示，从MRI关闭和开启的静态PET图像组合中得出的最活跃网络成分是额极、额上回、颞中回和枕极。在MRI关闭和开启模式下，fMRI指标与rCMRGlu之间均发现高相关系数（P < 0.05）。我们的结果系统地评估了同步fMRI扫描对集成PET/MRI系统中人类脑代谢定量的影响。
