Department of Biomedical Engineering and Physics, Amsterdam University Medical Center, location AMC, Amsterdam, the Netherlands.
Amsterdam Cardiovascular Sciences Research Institute, Amsterdam, the Netherlands.
NMR Biomed. 2024 Jul;37(7):e5029. doi: 10.1002/nbm.5029. Epub 2023 Sep 2.
Cerebrospinal fluid (CSF) has historically been considered to function as a sink for brain-derived waste disposal. Recent work suggested that CSF interacts even more intensely with brain tissue than previously recognized, through perivascular spaces that penetrate the brain. Cardiac pulsations, vasomotion, and respiration have been suggested to drive CSF flow in these perivascular spaces, thereby enhancing waste clearance. However, the intrinsic role of CSF production in relation to its distribution volume (turnover) is not an explicit component of recent concepts on brain clearance. Here, we review the work on CSF turnover and volume, focusing on preclinical evidence. Herein, we highlight the use of MRI in establishing CSF-related parameters. We describe the impact of sleep, effect of anesthesia, aging, and hypertension on CSF turnover, and how this relates to brain clearance. Evaluation of the available evidence suggests that CSF turnover is a major determinant in brain clearance. In addition, we propose that several putative drivers of brain clearance, but also conditions associated with impaired clearance, such as aging, may actually relate to altered CSF turnover.
脑脊液（CSF）在历史上一直被认为是大脑中废物清除的“汇”。最近的研究表明，CSF 通过穿透脑组织的血管周围间隙与脑组织的相互作用比以前认识到的更为强烈。心脏搏动、血管运动和呼吸被认为可以驱动这些血管周围间隙中的 CSF 流动，从而增强废物清除。然而，CSF 产生与其分布容积（周转率）之间的内在关系并不是最近关于大脑清除的概念的明确组成部分。在这里，我们回顾了 CSF 周转率和体积的研究工作，重点是临床前证据。在此，我们强调了 MRI 在建立 CSF 相关参数中的应用。我们描述了睡眠、麻醉效果、衰老和高血压对 CSF 周转率的影响，以及这与大脑清除的关系。对现有证据的评估表明，CSF 周转率是大脑清除的主要决定因素。此外，我们提出，几种被认为是大脑清除的驱动力的因素，以及与清除受损相关的情况，如衰老，实际上可能与 CSF 周转率的改变有关。
