Li Haotian, Zu Tao, Hsu Yi-Cheng, Zhao Zhiyong, Liu Ruibin, Zheng Tianshu, Li Qing, Sun Yi, Liu Daihong, Zhang Jiuquan, Zhang Yi, Wu Dan
Key Laboratory for Biomedical Engineering of Ministry of Education, Department of Biomedical Engineering, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, Zhejiang, China.
MR Collaboration, Siemens Healthcare China, Shanghai, China.
J Magn Reson Imaging. 2023 Feb;57(2):446-453. doi: 10.1002/jmri.28311. Epub 2022 Jun 20.
Oscillating gradient diffusion MRI (dMRI) enables measurements at a short diffusion-time (t ), but it is challenging for clinical systems. Particularly, the low b-value and low resolution may give rise to cerebrospinal fluid (CSF) contamination.
To assess the effect of CSF partial volume on t -dMRI measurements and efficacy of inversion-recovery (IR) prepared oscillating and pulsed gradient dMRI sequence to improve t -dMRI measurements in the human brain.
Prospective.
Ten normal volunteers and six glioma patients.
FIELD STRENGTH/SEQUENCE: A 3 T; three-dimensional (3D) IR-prepared oscillating gradient-prepared gradient spin-echo (GRASE) and two-dimensional (2D) IR-prepared oscillating gradient echo-planar imaging (EPI) sequences.
We assessed the t -dependent patterns of apparent diffusion coefficient (ADC) in several gray and white matter structures, including the hippocampal subfields (head, body, and tail), cortical gray matter, thalamus, and posterior white matter in normal volunteers. Pulsed gradient (0 Hz) and oscillating gradients at frequencies of 20 Hz, 40 Hz, and 60 Hz dMRI were acquired with GRASE and EPI sequences with or without the IR module. We also tested the t -dependency patterns in glioma patients using the EPI sequence with or without the IR module.
The differences in ADC across the different t s were compared by one-way ANOVA followed by post hoc pairwise t-tests with Bonferroni correction.
In the healthy subjects, brain regions that were possibly contaminated by CSF signals, such as the hippocampus (head, body, and tail) and cortical gray matter, t -dependent ADC changes were only significant with the IR-prepared 2D and 3D sequences but not with the non-IR sequences. In brain glioblastomas patients, significantly higher t -dependence was observed in the tumor region with the IR module than that without IR (slope = 0.0196 μm /msec vs. 0.0034 μm /msec ).
The IR-prepared sequence effectively suppressed the CSF partial volume effect and significantly improved the t -dependent measurements in the human brain.
1 TECHNICAL EFFICACY: Stage 1.
振荡梯度扩散磁共振成像（dMRI）能够在短扩散时间（t）下进行测量，但对于临床系统而言具有挑战性。特别是，低b值和低分辨率可能会导致脑脊液（CSF）污染。
评估脑脊液部分容积对t-dMRI测量的影响，以及反转恢复（IR）准备的振荡和脉冲梯度dMRI序列在改善人脑t-dMRI测量方面的效果。
前瞻性研究。
10名正常志愿者和6名胶质瘤患者。
场强/序列：3T；三维（3D）IR准备的振荡梯度准备的梯度自旋回波（GRASE）序列和二维（2D）IR准备的振荡梯度回波平面成像（EPI）序列。
我们评估了正常志愿者中几个灰质和白质结构（包括海马亚区（头部、体部和尾部）、皮质灰质、丘脑和后部白质）中表观扩散系数（ADC）的t依赖性模式。使用带有或不带有IR模块的GRASE和EPI序列，采集了0Hz的脉冲梯度和20Hz、40Hz和60Hz频率的振荡梯度dMRI。我们还使用带有或不带有IR模块的EPI序列测试了胶质瘤患者中的t依赖性模式。
通过单因素方差分析比较不同t值下ADC的差异，随后进行带有Bonferroni校正的事后两两t检验。
在健康受试者中，可能被脑脊液信号污染的脑区，如海马（头部、体部和尾部）和皮质灰质，只有使用IR准备的2D和3D序列时，t依赖性ADC变化才显著，而使用非IR序列时不显著。在脑胶质母细胞瘤患者中，肿瘤区域使用带有IR模块的序列比不使用IR模块时观察到的t依赖性显著更高（斜率分别为0.0196μm²/msec和0.0034μm²/msec）。
IR准备的序列有效地抑制了脑脊液部分容积效应，并显著改善了人脑的t依赖性测量。
1级 技术效能：1级
