Glymphatic Cerebrospinal Fluid and Solute Transport Quantified by

the past decade there has been an enormous progress in our understanding of fluid and solute transport in the central nervous system (CNS). This is due to a number of factors, including important developments in whole brain imaging technology and computational fluid dynamics analysis employed for the elucidation of glymphatic transport function in the live animal and human brain. In this paper, we review the technical aspects of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) in combination with administration of Gd-based tracers into the cerebrospinal fluid (CSF) for tracking glymphatic solute and fluid transport in the CNS as well as lymphatic drainage. Used in conjunction with advanced computational processing methods including optimal mass transport analysis, one gains new insights into the biophysical forces governing solute transport in the CNS which leads to intriguing new research directions. Considering drainage pathways, we review the novel T1 mapping technique for quantifying glymphatic transport and cervical lymph node drainage concurrently in the same subject. We provide an overview of knowledge gleaned from DCE-MRI studies of glymphatic transport and meningeal lymphatic drainage. Finally, we introduce positron emission tomography (PET) and CSF administration of radiotracers as an alternative method to explore other pharmacokinetic aspects of CSF transport into brain parenchyma as well as efflux pathways. This article is part of a Special Issue entitled: Brain imaging. (c) 2020 IBRO. Published by Elsevier Ltd. All rights reserved.

Automated summary

In the past decade, significant progress has been made in understanding fluid and solute transport in the CNS, thanks to advancements in imaging technology and computational fluid dynamics analysis. This paper reviews the technical aspects of DCE-MRI and Gd-based tracers for tracking glymphatic transport in the CNS, providing new insights into biophysical forces governing solute transport and drainage pathways.