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REVIEW ARTICLE

From ventricles to lymphatics: A systems-level framework for brain fluid transport

Khaled A. Abdel-Sater1*
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1 Department of Dental and Medical Sciences, Faculty of Dentistry, Mutah University, Al-Karak, Jordan
Advanced Neurology, 026090002 https://doi.org/10.36922/AN026090002
Received: 27 February 2026 | Revised: 6 June 2026 | Accepted: 15 June 2026 | Published online: 7 July 2026
© 2026 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
Abstract

Understanding of cerebrospinal fluid (CSF) dynamics has undergone a major transformation, shifting from the traditional concept of unidirectional CSF circulation toward a broader framework that incorporates distributed glymphatic and lymphatic clearance systems. This review integrates classical CSF physiology with recent discoveries in glymphatic transport, meningeal lymphatics, and interstitial fluid exchange to provide a unified perspective on brain fluid homeostasis. Evidence from anatomical, physiological, computational, and clinical studies demonstrates that intracranial fluid transport operates through a hierarchical, highly coordinated network extending from microscopic astrocytic interfaces and perivascular pathways to large-scale venous and lymphatic drainage routes. The analysis highlights that diffusion and advection are not opposing mechanisms but complementary, state-dependent processes influenced by vascular pulsatility, sleep–wake cycles, respiratory dynamics, and tissue architecture. Emerging data further indicate that dysfunction within these clearance pathways may contribute to impaired metabolic waste removal, neuroinflammation, hydrocephalus, and neurodegenerative disorders. Rather than functioning as a simple circulation pathway, brain fluid movement should therefore be conceptualized as a modular hydrodynamic system integrating cellular, vascular, and lymphatic components. This updated framework may support the development of more targeted diagnostic and therapeutic strategies for neurological diseases associated with impaired fluid transport and clearance.

Keywords
Cerebrospinal fluid hydrodynamics
Glymphatic pathway
Diffusion versus convection
Lymphatic drainage
Hydrocephalus
Alzheimer’s disease
Funding
None.
Conflict of interest
The author declares no competing financial or non-financial interests relevant to this work.
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