Komlosh M E, Benjamini D, Williamson N W, Horkay F, Hutchinson E B, Basser P J
Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA; The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, USA.
Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
Magn Reson Imaging. 2019 Feb;56:181-186. doi: 10.1016/j.mri.2018.10.007. Epub 2018 Oct 19.
The glymphatic system is a recently discovered transport system, mediated by cerebral spinal fluid (CSF), that clears metabolic and cellular waste products in the brain. This system's function in the brain is analogous to that of the lymphatic system in the rest of the mammalian body. It is hypothesized that CSF clears harmful chemicals from the brain by flowing through interstitial spaces in the brain during sleep. While there is growing recognition of the critical role the glymphatic system plays in maintaining normal brain health and in explaining pathology, there are few noninvasive imaging methods that measure and characterize the efficacy of glymphatic transport in vivo. In this study we designed, constructed, and tested a glymphatic transport magnetic resonance imaging (MRI) flow phantom, which combines regions that mimic CSF-filled ventricles and brain interstitial space. We tested high- and low-q space diffusion MRI and diffusion tensor imaging (DTI) acquisitions to determine if they could detect, measure, and map interstitial glymphatic flows. The results suggest that, under certain flow conditions, diffusion-weighted MRI can detect the enhanced mixing that occurs during glymphatic clearance.
类淋巴系统是一种最近发现的由脑脊液（CSF）介导的转运系统，它能清除大脑中的代谢和细胞废物。该系统在大脑中的功能类似于哺乳动物身体其他部位的淋巴系统。据推测，脑脊液在睡眠期间流经大脑的间质间隙，从而清除大脑中的有害化学物质。虽然人们越来越认识到类淋巴系统在维持正常脑健康和解释病理过程中所起的关键作用，但很少有非侵入性成像方法能够在体内测量和表征类淋巴转运的功效。在本研究中，我们设计、构建并测试了一种类淋巴转运磁共振成像（MRI）流动模型，该模型结合了模拟充满脑脊液的脑室和脑间质间隙的区域。我们测试了高q空间扩散MRI和扩散张量成像（DTI）采集，以确定它们是否能够检测、测量和绘制间质类淋巴流动。结果表明，在某些流动条件下，扩散加权MRI可以检测到类淋巴清除过程中发生的增强混合。
