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Madarasz A, Xin L, Proulx ST. Clearance of erythrocytes from the subarachnoid space through cribriform plate lymphatics in female mice. EBioMedicine 2024; 107:105295. [PMID: 39178745 PMCID: PMC11388277 DOI: 10.1016/j.ebiom.2024.105295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 08/02/2024] [Accepted: 08/06/2024] [Indexed: 08/26/2024] Open
Abstract
BACKGROUND Atraumatic subarachnoid haemorrhage (SAH) is associated with high morbidity and mortality. Proposed mechanisms for red blood cell (RBC) clearance from the subarachnoid space (SAS) are erythrolysis, erythrophagocytosis or through efflux along cerebrospinal fluid (CSF) drainage routes. We aimed to elucidate the mechanisms of RBC clearance from the SAS to identify targetable efflux pathways. METHODS Autologous fluorescently-labelled RBCs along with PEGylated 40 kDa near-infrared tracer (P40D800) were infused via the cisterna magna (i.c.m.) in female reporter mice for lymphatics or for resident phagocytes. Drainage pathways for RBCs to extracranial lymphatics were evaluated by in vivo and in situ near-infrared imaging and by immunofluorescent staining on decalcified cranial tissue or dural whole-mounts. FINDINGS RBCs drained to the deep cervical lymph nodes 15 min post i.c.m. infusion, showing similar dynamics as P40D800 tracer. Postmortem in situ imaging and histology showed perineural accumulations of RBCs around the optic and olfactory nerves. Numerous RBCs cleared through the lymphatics of the cribriform plate, whilst histology showed no relevant fast RBC clearance through dorsal dural lymphatics or by tissue-resident macrophage-mediated phagocytosis. INTERPRETATION This study provides evidence for rapid RBC drainage through the cribriform plate lymphatic vessels, whilst neither fast RBC clearance through dorsal dural lymphatics nor through spinal CSF efflux or phagocytosis was observed. Similar dynamics of P40D800 and RBCs imply open pathways for clearance that do not impose a barrier for RBCs. This finding suggests further evaluation of the cribriform plate lymphatic function and potential pharmacological targeting in models of SAH. FUNDING Swiss National Science Foundation (310030_189226), SwissHeart (FF191155).
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Affiliation(s)
- Adrian Madarasz
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
| | - Li Xin
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
| | - Steven T Proulx
- Theodor Kocher Institute, University of Bern, Bern, Switzerland.
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2
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Freret ME, Boire A. The anatomic basis of leptomeningeal metastasis. J Exp Med 2024; 221:e20212121. [PMID: 38451255 PMCID: PMC10919154 DOI: 10.1084/jem.20212121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 09/20/2022] [Accepted: 02/08/2024] [Indexed: 03/08/2024] Open
Abstract
Leptomeningeal metastasis (LM), or spread of cancer to the cerebrospinal fluid (CSF)-filled space surrounding the central nervous system, is a fatal complication of cancer. Entry into this space poses an anatomical challenge for cancer cells; movement of cells between the blood and CSF is tightly regulated by the blood-CSF barriers. Anatomical understanding of the leptomeninges provides a roadmap of corridors for cancer entry. This Review describes the anatomy of the leptomeninges and routes of cancer spread to the CSF. Granular understanding of LM by route of entry may inform strategies for novel diagnostic and preventive strategies as well as therapies.
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Affiliation(s)
- Morgan E. Freret
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Adrienne Boire
- Department of Neurology, Human Oncology and Pathogenesis Program, Brain Tumor Center, Memorial Sloan Kettering Cancer Center, New York, NY, USA
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3
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Tong XJ, Akdemir G, Wadhwa M, Verkman AS, Smith AJ. Large molecules from the cerebrospinal fluid enter the optic nerve but not the retina of mice. Fluids Barriers CNS 2024; 21:1. [PMID: 38178155 PMCID: PMC10768282 DOI: 10.1186/s12987-023-00506-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 12/21/2023] [Indexed: 01/06/2024] Open
Abstract
It has been proposed that cerebrospinal fluid (CSF) can enter and leave the retina and optic nerve along perivascular spaces surrounding the central retinal vessels as part of an aquaporin-4 (AQP4) dependent ocular 'glymphatic' system. Here, we injected fluorescent dextrans and antibodies into the CSF of mice at the cisterna magna and measured their distribution in the optic nerve and retina. We found that uptake of dextrans in the perivascular spaces and parenchyma of the optic nerve is highly sensitive to the cisternal injection rate, where high injection rates, in which dextran disperses fully in the sub-arachnoid space, led to uptake along the full length of the optic nerve. Accumulation of dextrans in the optic nerve did not differ significantly in wild-type and AQP4 knockout mice. Dextrans did not enter the retina, even when intracranial pressure was greatly increased over intraocular pressure. However, elevation of intraocular pressure reduced accumulation of fluorescent dextrans in the optic nerve head, and intravitreally injected dextrans left the retina via perivascular spaces surrounding the central retinal vessels. Human IgG distributed throughout the perivascular and parenchymal areas of the optic nerve to a similar extent as dextran following cisternal injection. However, uptake of a cisternally injected AQP4-IgG antibody, derived from a seropositive neuromyelitis optica spectrum disorder subject, was limited by AQP4 binding. We conclude that large molecules injected in the CSF can accumulate along the length of the optic nerve if they are fully dispersed in the optic nerve sub-arachnoid space but that they do not enter the retina.
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Affiliation(s)
- Xiao J Tong
- Department of Ophthalmology, University of California San Francisco, San Francisco, CA, 94131, USA
| | - Gokhan Akdemir
- Departments of Medicine and Physiology, University of California San Francisco, San Francisco, CA, 94131, USA
| | - Meetu Wadhwa
- Departments of Medicine and Physiology, University of California San Francisco, San Francisco, CA, 94131, USA
| | - Alan S Verkman
- Departments of Medicine and Physiology, University of California San Francisco, San Francisco, CA, 94131, USA
| | - Alex J Smith
- Department of Ophthalmology, University of California San Francisco, San Francisco, CA, 94131, USA.
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4
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Pan S, Yang PH, DeFreitas D, Ramagiri S, Bayguinov PO, Hacker CD, Snyder AZ, Wilborn J, Huang H, Koller GM, Raval DK, Halupnik GL, Sviben S, Achilefu S, Tang R, Haller G, Quirk JD, Fitzpatrick JAJ, Esakky P, Strahle JM. Gold nanoparticle-enhanced X-ray microtomography of the rodent reveals region-specific cerebrospinal fluid circulation in the brain. Nat Commun 2023; 14:453. [PMID: 36707519 PMCID: PMC9883388 DOI: 10.1038/s41467-023-36083-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 01/12/2023] [Indexed: 01/28/2023] Open
Abstract
Cerebrospinal fluid (CSF) is essential for the development and function of the central nervous system (CNS). However, the brain and its interstitium have largely been thought of as a single entity through which CSF circulates, and it is not known whether specific cell populations within the CNS preferentially interact with the CSF. Here, we develop a technique for CSF tracking, gold nanoparticle-enhanced X-ray microtomography, to achieve micrometer-scale resolution visualization of CSF circulation patterns during development. Using this method and subsequent histological analysis in rodents, we identify previously uncharacterized CSF pathways from the subarachnoid space (particularly the basal cisterns) that mediate CSF-parenchymal interactions involving 24 functional-anatomic cell groupings in the brain and spinal cord. CSF distribution to these areas is largely restricted to early development and is altered in posthemorrhagic hydrocephalus. Our study also presents particle size-dependent CSF circulation patterns through the CNS including interaction between neurons and small CSF tracers, but not large CSF tracers. These findings have implications for understanding the biological basis of normal brain development and the pathogenesis of a broad range of disease states, including hydrocephalus.
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Affiliation(s)
- Shelei Pan
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Peter H Yang
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Dakota DeFreitas
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Sruthi Ramagiri
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Peter O Bayguinov
- Washington University Center for Cellular Imaging, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Carl D Hacker
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Abraham Z Snyder
- Department of Radiology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Neurology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Jackson Wilborn
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Hengbo Huang
- Department of Radiology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Gretchen M Koller
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Dhvanii K Raval
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Grace L Halupnik
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Sanja Sviben
- Washington University Center for Cellular Imaging, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Samuel Achilefu
- Department of Biomedical Engineering, UT Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Rui Tang
- Department of Radiology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Gabriel Haller
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Neurology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Genetics, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - James D Quirk
- Department of Radiology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - James A J Fitzpatrick
- Washington University Center for Cellular Imaging, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Neuroscience, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
- Department of Cell Biology and Physiology, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Prabagaran Esakky
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Jennifer M Strahle
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA.
- Department of Orthopedic Surgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA.
- Department of Pediatrics, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA.
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Fedin AI. [The glymphatic system in the brain - neurobiology and clinical pathology]. Zh Nevrol Psikhiatr Im S S Korsakova 2023; 123:13-19. [PMID: 37315237 DOI: 10.17116/jnevro202312305113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Given new information about the neurobiology of the processes of removal of waste products of the brain, consisting of the lymphatic vessels into the dura and the glial-lymphatic (glymphatic) system. The role of astrocytes and water-conducting channels located on them in cell membranes formed by the protein aquaporin-4 is emphasized. The connection between the functioning of the glymphatic system and the slow phase of sleep is discussed. Possible mechanisms for the development of cognitive impairments in violation of the function of the glymphatic system and a delay in the elimination of β-amyloid are shown. Directions of pathogenetic therapy are given.
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Affiliation(s)
- A I Fedin
- Pirogov Russian National Research Medical University, Moscow, Russia
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6
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Zhou Y, Ran W, Luo Z, Wang J, Fang M, Wei K, Sun J, Lou M. Impaired peri-olfactory cerebrospinal fluid clearance is associated with ageing, cognitive decline and dyssomnia. EBioMedicine 2022; 86:104381. [PMID: 36442319 PMCID: PMC9706530 DOI: 10.1016/j.ebiom.2022.104381] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 11/09/2022] [Accepted: 11/09/2022] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Animal experiments have demonstrated the dependency of cerebrospinal fluid clearance function on age and sleep, which partially underlay the cognitive decline in the elderly. However, human evidence is lacking, which could be mainly attributed to the limited methods of cerebrospinal fluid clearance function assessment. METHOD Serial T1-weighted and T2-fluid attenuated inversion recovery imaging were performed in 92 patients before and at multiple time points including 4.5 h, 15 h and 39 h after intrathecal injection of contrast agent to visualize the putative meningeal lymphatic pathway, peri-olfactory nerve pathway, and peri-optic nerve pathway. We defined the clearance function as the percentage change in signal unit ratio of critical locations in these pathways from baseline to 39 h after intrathecal injection, and further analysed their relationships with age, sleep, and cognitive function. FINDINGS Cerebrospinal fluid clearance through the putative meningeal lymphatic and perineural pathways were clearly visualized. The clearance function of putative meningeal lymphatic and perineural pathways were impaired with ageing (all P < 0.05). The clearance function through peri-olfactory nerve pathway in inferior turbinate was positively correlated with sleep quality and cognitive function (both P < 0.05), and mediated the association of sleep quality with cognitive function (percent change in β [bootstrap 95% CI]: 33% [-0.220, -0.007]). INTERPRETATION The impaired clearance through putative peri-olfactory nerve pathway may explain the cognitive decline in patients with sleep disturbance. The study shows a promising method to assess cerebrospinal fluid clearance function of putative peri-neural pathways via dynamic magnetic resonance imaging with intrathecal injection of contrast agent. FUNDING This work was supported by the National Natural Science Foundation of China (81971101, 82171276 and 82101365).
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Affiliation(s)
- Ying Zhou
- Department of Neurology, The Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Wang Ran
- Department of Neurology, The Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Zhongyu Luo
- Department of Neurology, The Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Jianan Wang
- Department of Neurology, The Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Mengmeng Fang
- Department of Radiology, The Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Kai Wei
- Department of Radiology, The Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Jianzhong Sun
- Department of Radiology, The Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Min Lou
- Department of Neurology, The Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China,Corresponding author. Department of Neurology, The Second Affiliated Hospital of Zhejiang University, School of Medicine, #88 Jiefang Road, Hangzhou, China.
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7
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Wilting J, Becker J. The lymphatic vascular system: much more than just a sewer. Cell Biosci 2022; 12:157. [PMID: 36109802 PMCID: PMC9476376 DOI: 10.1186/s13578-022-00898-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 09/06/2022] [Indexed: 11/18/2022] Open
Abstract
Almost 400 years after the (re)discovery of the lymphatic vascular system (LVS) by Gaspare Aselli (Asellius G. De lactibus, sive lacteis venis, quarto vasorum mesaraicorum genere, novo invento Gasparis Asellii Cremo. Dissertatio. (MDCXXIIX), Milan; 1628.), structure, function, development and evolution of this so-called 'second' vascular system are still enigmatic. Interest in the LVS was low because it was (and is) hardly visible, and its diseases are not as life-threatening as those of the blood vascular system. It is not uncommon for patients with lymphedema to be told that yes, they can live with it. Usually, the functions of the LVS are discussed in terms of fluid homeostasis, uptake of chylomicrons from the gut, and immune cell circulation. However, the broad molecular equipment of lymphatic endothelial cells suggests that they possess many more functions, which are also reflected in the pathophysiology of the system. With some specific exceptions, lymphatics develop in all organs. Although basic structure and function are the same regardless their position in the body wall or the internal organs, there are important site-specific characteristics. We discuss common structure and function of lymphatics; and point to important functions for hyaluronan turn-over, salt balance, coagulation, extracellular matrix production, adipose tissue development and potential appetite regulation, and the influence of hypoxia on the regulation of these functions. Differences with respect to the embryonic origin and molecular equipment between somatic and splanchnic lymphatics are discussed with a side-view on the phylogeny of the LVS. The functions of the lymphatic vasculature are much broader than generally thought, and lymphatic research will have many interesting and surprising aspects to offer in the future.
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Affiliation(s)
- Jörg Wilting
- Department of Anatomy and Cell Biology, University Medical School Göttingen, Göttingen, Germany.
| | - Jürgen Becker
- Department of Anatomy and Cell Biology, University Medical School Göttingen, Göttingen, Germany
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8
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Holmlund P, Støverud KH, Eklund A. Mathematical modelling of the CSF system: effects of microstructures and posture on optic nerve subarachnoid space dynamics. Fluids Barriers CNS 2022; 19:67. [PMID: 36042452 PMCID: PMC9426285 DOI: 10.1186/s12987-022-00366-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 08/18/2022] [Indexed: 11/21/2022] Open
Abstract
Background The pressure difference between the eye and brain in upright postures may be affected by compartmentalization of the optic nerve subarachnoid space (ONSAS). Both pressure and deformation will depend on the microstructures of the ONSAS, and most likely also on ocular glymphatic clearance. Studying these factors could yield important knowledge regarding the translaminar pressure difference, which is suspected to play a role in normal-tension glaucoma. Methods A compartment model coupling the ONSAS with the craniospinal CSF system was used to investigate the effects of microstructures on the pressure transfer through the ONSAS during a posture change from supine to upright body postures. ONSAS distensibility was based on MRI measurements. We also included ocular glymphatic flow to investigate how local pressure gradients alter this flow with changes in posture. Results A compartmentalization of the ONSAS occurred in the upright posture, with ONSAS porosity (degree of microstructural content) affecting the ONSAS pressure (varying the supine/baseline porosity from 1.0 to 0.75 yielded pressures between − 5.3 and − 2 mmHg). Restricting the minimum computed porosity (occurring in upright postures) to 0.3 prevented compartmentalization, and the ONSAS pressure could equilibrate with subarachnoid space pressure (− 6.5 mmHg) in \documentclass[12pt]{minimal}
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\begin{document}$$\le$$\end{document}≤ 1 h. The ocular glymphatics analysis predicted that substantial intraocular-CSF flows could occur without substantial changes in the ONSAS pressure. The flow entering the ONSAS in supine position (both from the intraocular system and from the cranial subarachnoid space) exited the ONSAS through the optic nerve sheath, while in upright postures the flow through the ONSAS was redirected towards the cranial subarachnoid space. Conclusions Microstructures affect pressure transmission along the ONSAS, potentially contributing to ONSAS compartmentalization in upright postures. Different pathways for ocular glymphatic flow were predicted for different postures.
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Affiliation(s)
- Petter Holmlund
- Department of Radiation Sciences, Radiation Physics, Biomedical Engineering, Umeå University, 901 87, Umeå, Sweden.
| | - Karen-Helene Støverud
- Department of Radiation Sciences, Radiation Physics, Biomedical Engineering, Umeå University, 901 87, Umeå, Sweden.,Department of Health Research, SINTEF Digital, Trondheim, Norway
| | - Anders Eklund
- Department of Radiation Sciences, Radiation Physics, Biomedical Engineering, Umeå University, 901 87, Umeå, Sweden.,Umeå Center for Functional Brain Imaging, Umeå University, 901 87, Umeå, Sweden
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9
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Proulx ST, Engelhardt B. Central nervous system zoning: How brain barriers establish subdivisions for CNS immune privilege and immune surveillance. J Intern Med 2022; 292:47-67. [PMID: 35184353 PMCID: PMC9314672 DOI: 10.1111/joim.13469] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The central nervous system (CNS) coordinates all our body functions. Neurons in the CNS parenchyma achieve this computational task by high speed communication via electrical and chemical signals and thus rely on a strictly regulated homeostatic environment, which does not tolerate uncontrolled entry of blood components including immune cells. The CNS thus has a unique relationship with the immune system known as CNS immune privilege. Previously ascribed to the presence of blood-brain barriers and the lack of lymphatic vessels in the CNS parenchyma prohibiting, respectively, efferent and afferent connections with the peripheral immune system, it is now appreciated that CNS immune surveillance is ensured by cellular and acellular brain barriers that limit immune cell and mediator accessibility to specific compartments at the borders of the CNS. CNS immune privilege is established by a brain barriers anatomy resembling the architecture of a medieval castle surrounded by two walls bordering a castle moat. Built for protection and defense this two-walled rampart at the outer perimeter of the CNS parenchyma allows for accommodation of different immune cell subsets and efficient monitoring of potential danger signals derived from inside or outside of the CNS parenchyma. It enables effective mounting of immune responses within the subarachnoid or perivascular spaces, while leaving the CNS parenchyma relatively undisturbed. In this study, we propose that CNS immune privilege rests on the proper function of the brain barriers, which allow for CNS immune surveillance but prohibit activation of immune responses from the CNS parenchyma unless it is directly injured.
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Affiliation(s)
- Steven T Proulx
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
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10
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Zhang Z, Tan Q, Guo P, Huang S, Jia Z, Liu X, Feng H, Chen Y. NLRP3 inflammasome-mediated choroid plexus hypersecretion contributes to hydrocephalus after intraventricular hemorrhage via phosphorylated NKCC1 channels. J Neuroinflammation 2022; 19:163. [PMID: 35729645 PMCID: PMC9210649 DOI: 10.1186/s12974-022-02530-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 06/14/2022] [Indexed: 12/26/2022] Open
Abstract
Background Hydrocephalus is a severe complication of intracerebral hemorrhage with ventricular extension (ICH-IVH) and causes cerebrospinal fluid (CSF) accumulation. The choroid plexus epithelium plays an important role in CSF secretion and constitutes the blood–CSF barrier within the brain–immune system interface. Although the NLRP3 inflammasome, as a key component of the innate immune system, promotes neuroinflammation, its role in the pathogenesis of hydrocephalus after hemorrhage has not been investigated. Therefore, this study aimed to investigate the potential mechanism of NLRP3 in hydrocephalus to discover a potential marker for targeted therapy. Methods A rat model of hydrocephalus after ICH-IVH was developed through autologous blood infusion in wild-type and Nlrp3−/− rats. By studying the features and processes of the model, we investigated the relationship between the NLRP3 inflammasome and CSF hypersecretion in the choroid plexus. Results The ICH-IVH model rats showed ventricular dilation accompanied by CSF hypersecretion for 3 days. Based on the choroid plexus RNA-seq and proteomics results, we found that an inflammatory response was activated. The NLRP3 inflammasome was investigated, and the expression levels of NLRP3 inflammasome components reached a peak at 3 days after ICH-IVH. Inhibition of NLRP3 by an MCC950 inflammasome inhibitor or Nlrp3 knockout decreased CSF secretion and ventricular dilation and attenuated neurological deficits after ICH-IVH. The mechanism underlying the neuroprotective effects of NLRP3 inhibition involved decreased phosphorylation of NKCC1, which is a major protein that regulates CSF secretion by altering Na+- and K+-coupled water transport, via MCC950 or Nlrp3 knockout. In combination with the in vitro experiments, this experiment confirmed the involvement of the NLRP3/p-NKCC1 pathway and Na+ and K+ flux. Conclusions This study demonstrates that NKCC1 phosphorylation in the choroid plexus epithelium promotes NLRP3 inflammasome-mediated CSF hypersecretion and that NLRP3 plays an important role in the pathogenesis of hydrocephalus after hemorrhage. These findings provide a new therapeutic strategy for treating hydrocephalus. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-022-02530-x.
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Affiliation(s)
- Zhaoqi Zhang
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China.,Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.,Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Qiang Tan
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China.,Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.,Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Peiwen Guo
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China.,Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.,Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Suna Huang
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China.,Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.,Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Zhengcai Jia
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China.,Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.,Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Xin Liu
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China.,Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.,Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Hua Feng
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China. .,Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China. .,Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.
| | - Yujie Chen
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), 29 Gaotanyan Street, Shapingba District, Chongqing, 400038, China. .,Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China. .,Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China. .,CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
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11
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The Effect of Optic Nerve Sheath Fenestration on Intraocular Pressure in Patients With Idiopathic Intracranial Hypertension. J Neuroophthalmol 2022; 42:97-100. [DOI: 10.1097/wno.0000000000001235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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12
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Decker Y, Krämer J, Xin L, Müller A, Scheller A, Fassbender K, Proulx ST. Magnetic resonance imaging of cerebrospinal fluid outflow after low-rate lateral ventricle infusion in mice. JCI Insight 2021; 7:150881. [PMID: 34905509 PMCID: PMC8855808 DOI: 10.1172/jci.insight.150881] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The anatomical routes for the clearance of cerebrospinal fluid (CSF) remain incompletely understood. However, recent evidence has given strong support for routes leading to lymphatic vessels. A current debate centers upon the routes through which CSF can access lymphatics, with evidence emerging for either direct routes to meningeal lymphatics or along cranial nerves to reach lymphatics outside the skull. Here, a method was established to infuse contrast agent into the ventricles using indwelling cannulae during imaging of mice at 2 and 12 months of age by magnetic resonance imaging. As expected, a significant decline in overall CSF turnover was found with aging. Quantifications demonstrated that the bulk of the contrast agent flowed from the ventricles to the subarachnoid space in the basal cisterns. Comparatively little contrast agent signal was found at the dorsal aspect of the skull. The imaging dynamics from the two cohorts revealed that the contrast agent cleared from the cranium through the cribriform plate to the nasopharyngeal lymphatics. On decalcified sections, we confirmed that fluorescentlylabeled ovalbumin drains through the cribriform plate and can be found within lymphatics surrounding the nasopharynx. In conclusion, routes leading to nasopharyngeal lymphatics appear to be a major efflux pathway for cranial CSF.
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Affiliation(s)
- Yann Decker
- Department of Neurology, Saarland University, Homburg, Germany
| | - Jonas Krämer
- Department of Neurology, Saarland University, Homburg, Germany
| | - Li Xin
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
| | - Andreas Müller
- Clinic for Diagnostic and Interventional Radiology, Saarland University, Homburg, Germany
| | - Anja Scheller
- Department of Physiology, Saarland University, Homburg, Germany
| | | | - Steven T Proulx
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
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13
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Yurayart N, Ninvilai P, Chareonviriyaphap T, Kaewamatawong T, Thontiravong A, Tiawsirisup S. Pathogenesis of Thai duck Tembusu virus in BALB/c mice: Descending infection and neuroinvasive virulence. Transbound Emerg Dis 2021; 68:3529-3540. [PMID: 33326703 DOI: 10.1111/tbed.13958] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 11/22/2020] [Accepted: 12/12/2020] [Indexed: 12/15/2022]
Abstract
Duck Tembusu virus (DTMUV) is an emerging flavivirus that causes systemic disease in an avian host. The predominant cluster of DTMUV circulating in Thailand was recently classified as cluster 2.1. The pathogenesis of this virus has been extensively studied in avian hosts but not in mammalian hosts. Six-week-old BALB/c mice were intracerebrally or subcutaneously inoculated with Thai DTMUV to examine clinical signs, pathological changes, viral load and virus distribution. Results demonstrated that the virus caused disease in BALB/c mice by the intracerebral inoculation route. Infected mice demonstrated both systemic and neurological symptoms. Pathological changes and virus distribution were observed in all tested organs. Viral load in the brain was significantly higher than in other organs (p < .05), and the virus caused acute death in BALB/c mice. The virus was disseminated in all parts of the body, but no virus shedding was recorded in saliva and faeces. Findings highlighted the potential of Thai DTMUV to transmit disease in mammalian hosts.
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Affiliation(s)
- Nichapat Yurayart
- Animal Vector-Borne Disease Research Unit, Veterinary Parasitology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand
| | - Patchareeporn Ninvilai
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand
| | | | - Theerayuth Kaewamatawong
- Veterinary Pathology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand
| | - Aunyaratana Thontiravong
- Animal Vector-Borne Disease Research Unit, Veterinary Parasitology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand
| | - Sonthaya Tiawsirisup
- Animal Vector-Borne Disease Research Unit, Veterinary Parasitology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand
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14
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Fahmy LM, Chen Y, Xuan S, Haacke EM, Hu J, Jiang Q. All Central Nervous System Neuro- and Vascular-Communication Channels Are Surrounded With Cerebrospinal Fluid. Front Neurol 2021; 12:614636. [PMID: 34220663 PMCID: PMC8247447 DOI: 10.3389/fneur.2021.614636] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 04/29/2021] [Indexed: 12/15/2022] Open
Abstract
Background: Recent emerging evidence has highlighted the potential critical role of cerebrospinal fluid (CSF) in cerebral waste clearance and immunomodulation. It is already very well-established that the central nervous system (CNS) is completely submerged in CSF on a macro-level; but to what extent is this true on a micro-level? Specifically, within the peri-neural and peri-vascular spaces within the CNS parenchyma. Therefore, the objective of this study was to use magnetic resonance imaging (MRI) to simultaneously map the presence of CSF within all peri-neural (cranial and spinal nerves) and peri-vascular spaces in vivo in humans. Four MRI protocols each with five participants were used to image the CSF in the brain and spinal cord. Our findings indicated that all CNS neuro- and vascular-communication channels are surrounded with CSF. In other words, all peri-neural spaces surrounding the cranial and spinal nerves as well as all peri-vascular spaces surrounding MRI-visible vasculature were filled with CSF. These findings suggest that anatomically, substance exchange between the brain parenchyma and outside tissues including lymphatic ones can only occur through CSF pathways and/or vascular pathways, warranting further investigation into its implications in cerebral waste clearance and immunity.
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Affiliation(s)
- Lara M Fahmy
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University, Detroit, MI, United States
| | - Yongsheng Chen
- Department of Neurology, Wayne State University, Detroit, MI, United States
| | - Stephanie Xuan
- Department of Radiology, Wayne State University, Detroit, MI, United States
| | - E Mark Haacke
- Department of Radiology, Wayne State University, Detroit, MI, United States
| | - Jiani Hu
- Department of Radiology, Wayne State University, Detroit, MI, United States
| | - Quan Jiang
- Department of Neurology, Henry Ford Health System, Detroit, MI, United States
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15
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Holmlund P, Støverud KH, Wåhlin A, Wiklund U, Malm J, Jóhannesson G, Eklund A. Posture-Dependent Collapse of the Optic Nerve Subarachnoid Space: A Combined MRI and Modeling Study. Invest Ophthalmol Vis Sci 2021; 62:26. [PMID: 33877263 PMCID: PMC8083083 DOI: 10.1167/iovs.62.4.26] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose We hypothesize that a collapse of the optic nerve subarachnoid space (ONSAS) in the upright posture may protect the eyes from large translamina cribrosa pressure differences (TLCPD) believed to play a role in various optic nerve diseases (e.g., glaucoma). In this study, we combined magnetic resonance imaging (MRI) and mathematical modeling to investigate this potential ONSAS collapse and its effects on the TLCPD. Methods First, we performed MRI on six healthy volunteers in 6° head-down tilt (HDT) and 13° head-up tilt (HUT) to assess changes in ONSAS volume (measured from the eye to the optic canal) with changes in posture. The volume change reflects optic nerve sheath (ONS) distensibility. Second, we used the MRI data and mathematical modeling to simulate ONSAS pressure and the potential ONSAS collapse in a 90° upright posture. Results The MRI showed a 33% decrease in ONSAS volume from the HDT to HUT (P < 0.001). In the upright posture, the simulations predicted an ONSAS collapse 25 mm behind lamina cribrosa, disrupting the pressure communication between the ONSAS and the intracranial subarachnoid space. The collapse reduced the simulated postural increase in TLCPD by roughly 1 mm Hg, although this reduction was highly sensitive to ONS distensibility, varying between 0 and 4.8 mm Hg when varying the distensibility by ± 1 SD. Conclusions The ONSAS volume along the optic nerve is posture dependent. The simulations supported the hypothesized ONSAS collapse in the upright posture and showed that even small changes in ONS stiffness/distensibility may affect the TLCPD.
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Affiliation(s)
- Petter Holmlund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | | | - Anders Wåhlin
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
| | - Urban Wiklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Gauti Jóhannesson
- Department of Clinical Sciences, Ophthalmology, Umeå University, Umeå, Sweden.,Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.,Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
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16
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Yankova G, Bogomyakova O, Tulupov A. The glymphatic system and meningeal lymphatics of the brain: new understanding of brain clearance. Rev Neurosci 2021; 32:693-705. [PMID: 33618444 DOI: 10.1515/revneuro-2020-0106] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 01/31/2021] [Indexed: 12/25/2022]
Abstract
The glymphatic system and meningeal lymphatics have recently been characterized. Glymphatic system is a glia-dependent system of perivascular channels, and it plays an important role in the removal of interstitial metabolic waste products. The meningeal lymphatics may be a key drainage route for cerebrospinal fluid into the peripheral blood, may contribute to inflammatory reaction and central nervous system (CNS) immune surveillance. Breakdowns and dysfunction of the glymphatic system and meningeal lymphatics play a crucial role in age-related brain changes, the pathogenesis of neurovascular and neurodegenerative diseases, as well as in brain injuries and tumors. This review discusses the relationship recently characterized meningeal lymphatic vessels with the glymphatic system, which provides perfusion of the CNS with cerebrospinal and interstitial fluids. The review also presents the results of human studies concerning both the presence of meningeal lymphatics and the glymphatic system. A new understanding of how aging, medications, sleep and wake cycles, genetic predisposition, and even body posture affect the brain drainage system has not only changed the idea of brain fluid circulation but has also contributed to an understanding of the pathology and mechanisms of neurodegenerative diseases.
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Affiliation(s)
- Galina Yankova
- Lavrentyev Institute of Hydrodynamics, Siberian Branch, Russian Academy of Sciences, Novosibirsk630090, Russia.,Novosibirsk State University, Novosibirsk630090,Russia
| | - Olga Bogomyakova
- International Tomography Center, Siberian Branch, Russian Academy of Sciences, Novosibirsk630090, Russia
| | - Andrey Tulupov
- Novosibirsk State University, Novosibirsk630090,Russia.,International Tomography Center, Siberian Branch, Russian Academy of Sciences, Novosibirsk630090, Russia.,Meshalkin National Medical Research Center, Ministry of Health of Russian Federation, Novosibirsk 630055, Russia
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17
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Proulx ST. Cerebrospinal fluid outflow: a review of the historical and contemporary evidence for arachnoid villi, perineural routes, and dural lymphatics. Cell Mol Life Sci 2021; 78:2429-2457. [PMID: 33427948 PMCID: PMC8004496 DOI: 10.1007/s00018-020-03706-5] [Citation(s) in RCA: 158] [Impact Index Per Article: 52.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 10/23/2020] [Accepted: 11/06/2020] [Indexed: 12/19/2022]
Abstract
Cerebrospinal fluid (CSF) is produced by the choroid plexuses within the ventricles of the brain and circulates through the subarachnoid space of the skull and spinal column to provide buoyancy to and maintain fluid homeostasis of the brain and spinal cord. The question of how CSF drains from the subarachnoid space has long puzzled scientists and clinicians. For many decades, it was believed that arachnoid villi or granulations, outcroppings of arachnoid tissue that project into the dural venous sinuses, served as the major outflow route. However, this concept has been increasingly challenged in recent years, as physiological and imaging evidence from several species has accumulated showing that tracers injected into the CSF can instead be found within lymphatic vessels draining from the cranium and spine. With the recent high-profile rediscovery of meningeal lymphatic vessels located in the dura mater, another debate has emerged regarding the exact anatomical pathway(s) for CSF to reach the lymphatic system, with one side favoring direct efflux to the dural lymphatic vessels within the skull and spinal column and another side advocating for pathways along exiting cranial and spinal nerves. In this review, a summary of the historical and contemporary evidence for the different outflow pathways will be presented, allowing the reader to gain further perspective on the recent advances in the field. An improved understanding of this fundamental physiological process may lead to novel therapeutic approaches for a wide range of neurological conditions, including hydrocephalus, neurodegeneration and multiple sclerosis.
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Affiliation(s)
- Steven T Proulx
- Theodor Kocher Institute, University of Bern, Bern, Switzerland.
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18
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Brady M, Rahman A, Combs A, Venkatraman C, Kasper RT, McQuaid C, Kwok WCE, Wood RW, Deane R. Cerebrospinal fluid drainage kinetics across the cribriform plate are reduced with aging. Fluids Barriers CNS 2020; 17:71. [PMID: 33256800 PMCID: PMC7706057 DOI: 10.1186/s12987-020-00233-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 11/20/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Continuous circulation and drainage of cerebrospinal fluid (CSF) are essential for the elimination of CSF-borne metabolic products and neuronal function. While multiple CSF drainage pathways have been identified, the significance of each to normal drainage and whether there are differential changes at CSF outflow regions in the aging brain are unclear. METHODS Dynamic in vivo imaging of near infrared fluorescently-labeled albumin was used to simultaneously visualize the flow of CSF at outflow regions on the dorsal side (transcranial and -spinal) of the central nervous system. This was followed by kinetic analysis, which included the elimination rate constants for these regions. In addition, tracer distribution in ex vivo tissues were assessed, including the nasal/cribriform region, dorsal and ventral surfaces of the brain, spinal cord, cranial dura, skull base, optic and trigeminal nerves and cervical lymph nodes. RESULTS Based on the in vivo data, there was evidence of CSF elimination, as determined by the rate of clearance, from the nasal route across the cribriform plate and spinal subarachnoid space, but not from the dorsal dural regions. Using ex vivo tissue samples, the presence of tracer was confirmed in the cribriform area and olfactory regions, around pial blood vessels, spinal subarachnoid space, spinal cord and cervical lymph nodes but not for the dorsal dura, skull base or the other cranial nerves. Also, ex vivo tissues showed retention of tracer along brain fissures and regions associated with cisterns on the brain surfaces, but not in the brain parenchyma. Aging reduced CSF elimination across the cribriform plate but not that from the spinal SAS nor retention on the brain surfaces. CONCLUSIONS Collectively, these data show that the main CSF outflow sites were the nasal region across the cribriform plate and from the spinal regions in mice. In young adult mice, the contribution of the nasal and cribriform route to outflow was much higher than from the spinal regions. In older mice, the contribution of the nasal route to CSF outflow was reduced significantly but not for the spinal routes. This kinetic approach may have significance in determining early changes in CSF drainage in neurological disorder, age-related cognitive decline and brain diseases.
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Affiliation(s)
- Molly Brady
- Departments of Neuroscience, University of Rochester, URMC, 601 Elmwood Avenue, Rochester, NY, 14642, USA
| | - Akib Rahman
- Departments of Neuroscience, University of Rochester, URMC, 601 Elmwood Avenue, Rochester, NY, 14642, USA
| | - Abigail Combs
- Departments of Neuroscience, University of Rochester, URMC, 601 Elmwood Avenue, Rochester, NY, 14642, USA
| | - Chethana Venkatraman
- Departments of Neuroscience, University of Rochester, URMC, 601 Elmwood Avenue, Rochester, NY, 14642, USA
| | - R Tristan Kasper
- Departments of Neurosurgery, University of Rochester, URMC, 601 Elmwood Avenue, Rochester, NY, 14642, USA
| | - Conor McQuaid
- Departments of Neuroscience, University of Rochester, URMC, 601 Elmwood Avenue, Rochester, NY, 14642, USA
| | - Wing-Chi Edmund Kwok
- Departments of Imaging Sciences, University of Rochester, URMC, 601 Elmwood Avenue, Rochester, NY, 14642, USA
| | - Ronald W Wood
- Departments of Neuroscience, University of Rochester, URMC, 601 Elmwood Avenue, Rochester, NY, 14642, USA
- Departments of Obstetrics and Gynecology, Urology, University of Rochester, URMC, 601 Elmwood Avenue, Rochester, NY, 14642, USA
| | - Rashid Deane
- Departments of Neuroscience, University of Rochester, URMC, 601 Elmwood Avenue, Rochester, NY, 14642, USA.
- Departments of Neurosurgery, University of Rochester, URMC, 601 Elmwood Avenue, Rochester, NY, 14642, USA.
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19
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McKnight CD, Rouleau RM, Donahue MJ, Claassen DO. The Regulation of Cerebral Spinal Fluid Flow and Its Relevance to the Glymphatic System. Curr Neurol Neurosci Rep 2020; 20:58. [PMID: 33074399 DOI: 10.1007/s11910-020-01077-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/25/2020] [Indexed: 01/08/2023]
Abstract
PURPOSE OF REVIEW The glymphatic system is a relatively new concept that has been associated with regulation of cerebrospinal fluid (CSF), as well as brain waste clearance. Novel techniques to study glymphatic dysfunction have in turn prompted a reassessment of brain physiology and underlying elements of neurological disease. This review incorporates a contemporary imaging perspective focused on understanding the regulation of CSF flow, thus expanding the putative clinical relevance of this system and the relationships between CSF flow and glymphatic function. RECENT FINDINGS MR imaging studies, especially those that employ intrathecal gadolinium contrast, have identified potentially new pathways regulating CSF production, absorption, and clearance. These studies, when viewed in the context of more historical anatomic descriptors of CSF production and absorption, provide a more robust description of CSF physiology and waste clearance. CSF production and resorption are under-investigated and could be related to various pathophysiologic processes in neurodegeneration. Anatomically based clinical exemplars of CSF clearance are discussed. Future studies should focus on linking glymphatic functionality with neurological disease.
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Affiliation(s)
- Colin D McKnight
- Department of Radiology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Renee M Rouleau
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Manus J Donahue
- Department of Radiology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Daniel O Claassen
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA.
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20
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Brain Glymphatic/Lymphatic Imaging by MRI and PET. Nucl Med Mol Imaging 2020; 54:207-223. [PMID: 33088350 DOI: 10.1007/s13139-020-00665-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/09/2020] [Accepted: 08/19/2020] [Indexed: 01/19/2023] Open
Abstract
Since glymphatic was proposed and meningeal lymphatic was discovered, MRI and even PET were introduced to investigate brain parenchymal interstitial fluid (ISF), cerebrospinal fluid (CSF), and lymphatic outflow in rodents and humans. Previous findings by ex vivo fluorescent microscopic, and in vivo two-photon imaging in rodents were reproduced using intrathecal contrast (gadobutrol and the similar)-enhanced MRI in rodents and further in humans. On dynamic MRI of meningeal lymphatics, in contrast to rodents, humans use mainly dorsal meningeal lymphatic pathways of ISF-CSF-lymphatic efflux. In mice, ISF-CSF exchange was examined thoroughly using an intra-cistern injection of fluorescent tracers during sleep, aging, and neurodegeneration yielding many details. CSF to lymphatic efflux is across arachnoid barrier cells over the dorsal dura in rodents and in humans. Meningeal lymphatic efflux to cervical lymph nodes and systemic circulation is also well-delineated especially in humans onintrathecal contrast MRI. Sleep- or anesthesia-related changes of glymphatic-lymphatic flow and the coupling of ISF-CSF-lymphatic drainage are major confounders ininterpreting brain glymphatic/lymphatic outflow in rodents. PET imaging in humans should be interpreted based on human anatomy and physiology, different in some aspects, using MRI recently. Based on the summary in this review, we propose non-invasive and longer-term intrathecal SPECT/PET or MRI studies to unravel the roles of brain glymphatic/lymphatic in diseases.
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21
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Yapicioglu H, Aslan N, Sertdemir Y, Yildizdas D, Gulasi S, Mert K. Determination of normal values of optic nerve sheath diameter in newborns with bedside ultrasonography. Early Hum Dev 2020; 145:104986. [PMID: 32335478 DOI: 10.1016/j.earlhumdev.2020.104986] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 12/07/2019] [Accepted: 02/13/2020] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Bedside sonographic opthalmic ultrasound measurement of optic nerve sheath diameter (ONSD) is an easy, portabl, noninvasive and a radiation free technique to determine increased intracranial pressure. This prospective, multicenter study was aimed to establish the range of normal values for ONSD in preterm and term newborns with a large study population. METHODS Newborns without intracranial pathology in the Newborn Intensive Care Units and in Obstetrics and Gynecology Departments were enrolled in the study. ONSD was measured at 3 mm distance behind of the right optic nerve head. As 3 mm distance was beyond the optic nerve head in some of the premature newborns, we had also measurements at 2 and 2.5 mm. RESULTS ONSD was measured in 554 newborns. Mean ONSD of preterm babies at 2, 2.5 and 3 mm distances were 3.2 ± 0.3 mm (range 2.0-4.2 mm), 3.3 ± 0.3 mm (range 2.2-4.5 mm) and 3.6 ± 0.2 mm (range 2.9-4.5 mm), (p2.0-2.5 mm < 0.001, p 2.5-3.0mm < 0.001, p2.0-3.0 mm < 0.001) respectively. Mean ONSD of term babies at 3 mm was higher than the mean ONSD of preterm babies in 33 weeks 0 day- 37 weeks 0 days group (p < 0.001). In correlation analysis, a significant, strong and positive correlation was found between ONSD measurements and gestational age, weight, height and head circumference at 2, 2.5 and 3 mm distances. CONCLUSION The normal values reported by the present study may be used for evaluating the ONSD of newborns with different conditions with increased incracranial pressure.
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Affiliation(s)
- Hacer Yapicioglu
- Cukurova University, Faculty of Medicine, Department of Pediatrics, Division of Neonatology, Turkey
| | - Nagehan Aslan
- Cukurova University, Faculty of Medicine, Department of Pediatrics, Division of Pediatric Intensive Care, Turkey.
| | - Yasar Sertdemir
- Cukurova University, Faculty of Medicine, Department of Biostatistics, Turkey
| | - Dincer Yildizdas
- Cukurova University, Faculty of Medicine, Department of Pediatrics, Division of Pediatric Intensive Care, Turkey
| | - Selvi Gulasi
- Adana City Training and Research Hospital, Department of Pediatrics, Division of Neonatology, Adana, Turkey
| | - Kurthan Mert
- Adana City Training and Research Hospital, Department of Pediatrics, Division of Neonatology, Adana, Turkey
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22
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Zhou Y, Cai J, Zhang W, Gong X, Yan S, Zhang K, Luo Z, Sun J, Jiang Q, Lou M. Impairment of the Glymphatic Pathway and Putative Meningeal Lymphatic Vessels in the Aging Human. Ann Neurol 2020; 87:357-369. [PMID: 31916277 DOI: 10.1002/ana.25670] [Citation(s) in RCA: 152] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 01/06/2020] [Accepted: 01/06/2020] [Indexed: 01/01/2023]
Abstract
OBJECTIVE Aging is a major risk factor for numerous neurological disorders, and the mechanisms underlying brain aging remain elusive. Recent animal studies demonstrated a tight relationship between impairment of the glymphatic pathway, meningeal lymphatic vessels, and aging. However, the relationship in the human brain remains uncertain. METHODS In this observational cohort study, patients underwent magnetic resonance imaging before and at multiple time points after intrathecal administration of a contrast agent. Head T1-weighted imaging was performed to assess the function of the glymphatic pathway and head high-resolution T2-fluid attenuated inversion recovery imaging to visualize putative meningeal lymphatic vessels (pMLVs). We measured the signal unit ratio (SUR) of 6 locations in the glymphatic pathway and pMLVs, defined the percentage change in SUR from baseline to 39 hours as the clearance of the glymphatic pathway and pMLVs, and then analyzed their relationships with aging. RESULTS In all patients (N = 35), the SUR of the glymphatic pathway and pMLVs changed significantly after intrathecal injection of the contrast agent. The clearance of both the glymphatic pathway and pMLVs was related to aging (all p < 0.05). The clearance of pMLVs was significantly related to the clearance of the glymphatic pathway (all p < 0.05), and the clearance of the glymphatic pathway was significantly faster in patients with early filling of pMLVs than those with late filling (all p < 0.05). INTERPRETATION We revealed that both the glymphatic pathway and pMLVs might be impaired in the aging human brain through the novel, clinically available method to simultaneously visualize their clearance. Our findings also support that in humans, pMLVs are the downstream of the glymphatic pathway. Ann Neurol 2020;87:357-369.
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Affiliation(s)
- Ying Zhou
- Department of Neurology, Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Jinsong Cai
- Department of Radiology, Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Wenhua Zhang
- Department of Neurology, Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Xiaoxian Gong
- Department of Neurology, Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Shenqiang Yan
- Department of Neurology, Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Kemeng Zhang
- Department of Neurology, Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Zhongyu Luo
- Department of Neurology, Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Jianzhong Sun
- Department of Radiology, Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
| | - Quan Jiang
- Department of Neurology, Henry Ford Health System, Detroit, MI
| | - Min Lou
- Department of Neurology, Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China
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El Damaty A, Marx S, Cohrs G, Vollmer M, Eltanahy A, El Refaee E, Baldauf J, Fleck S, Baechli H, Zohdi A, Synowitz M, Unterberg A, Schroeder HWS. ETV in infancy and childhood below 2 years of age for treatment of hydrocephalus. Childs Nerv Syst 2020; 36:2725-2731. [PMID: 32222800 PMCID: PMC7575462 DOI: 10.1007/s00381-020-04585-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 03/19/2020] [Indexed: 11/26/2022]
Abstract
PURPOSE Age and etiology play a crucial role in success of endoscopic third ventriculostomy (ETV) as a treatment of obstructive hydrocephalus. Outcome is worse in infants, and controversies still exist whether ETV is superior to shunt placement. We retrospectively analyzed 70 patients below 2 years from 4 different centers treated with ETV and assessed success. METHODS Children < 2 years who received an ETV within 1994-2018 were included. Patients were classified according to age and etiology; < 3, 4-12, and 13-24 months, etiologically; aqueductal stenosis, post-hemorrhagic-hydrocephalus (PHH), tumor-related, fourth ventricle outflow obstruction, with Chiari-type II and following CSF infection. We investigated statistically the predictors for ETV success through computing Kaplan-Meier estimates using patient's follow-up time and time to ETV failure. RESULTS We collected 70 patients. ETV success rate was 41.4%. The highest rate was in tumor-related hydrocephalus and fourth ventricle outlet obstruction (62.5%, 60%) and the lowest rate was in Chiari-type II and following infection (16.7%, 0%). The below 3 months age group showed relatively lower success rate (33.3%) in comparison to older groups which showed similar results (46.4%, 46.6%). Statistically, a previous VP shunt was a predictor for failure (p value < 0.05). CONCLUSION Factors suggesting a high possibility of failure were age < 3 months and etiology such as Chiari-type II or following infection. Altered CSF dynamics in patients with PHH and under-developed arachnoid villi may play a role in ETV failure. We do not recommend ETV as first line in children < 3 months of age or in case of Chiari II or following infection.
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Affiliation(s)
- Ahmed El Damaty
- Department of Neurosurgery, Heidelberg University Hospital, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.
| | - Sascha Marx
- Department of Neurosurgery, University Medicine Greifswald, Greifswald, Germany
| | - Gesa Cohrs
- Department of Neurosurgery, University Medical Center Schleswig-Holstein (UKSH), Campus Kiel, Kiel, Germany
| | - Marcus Vollmer
- Institute of Bioinformatics, University Medicine Greifswald, Greifswald, Germany
| | - Ahmed Eltanahy
- Mansoura University School of Medicine, Mansoura, Egypt
- Department of Experimental Medical Sciences, Faculty of Medicine, Lund University, Lund, Sweden
| | - Ehab El Refaee
- Department of Neurosurgery, University Medicine Greifswald, Greifswald, Germany
- Department of Neurosurgery, Cairo University, Cairo, Egypt
| | - Joerg Baldauf
- Department of Neurosurgery, University Medicine Greifswald, Greifswald, Germany
| | - Steffen Fleck
- Department of Neurosurgery, University Medicine Greifswald, Greifswald, Germany
| | - Heidi Baechli
- Department of Neurosurgery, Heidelberg University Hospital, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Ahmed Zohdi
- Department of Neurosurgery, Cairo University, Cairo, Egypt
| | - Michael Synowitz
- Department of Neurosurgery, University Medical Center Schleswig-Holstein (UKSH), Campus Kiel, Kiel, Germany
| | - Andreas Unterberg
- Department of Neurosurgery, Heidelberg University Hospital, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Henry W S Schroeder
- Department of Neurosurgery, University Medicine Greifswald, Greifswald, Germany
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24
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The Influence of Translaminar Pressure Gradient and Intracranial Pressure in Glaucoma: A Review. J Glaucoma 2019; 29:141-146. [DOI: 10.1097/ijg.0000000000001421] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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25
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Subarachnoid cerebrospinal fluid is essential for normal development of the cerebral cortex. Semin Cell Dev Biol 2019; 102:28-39. [PMID: 31786096 DOI: 10.1016/j.semcdb.2019.11.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 11/14/2019] [Accepted: 11/22/2019] [Indexed: 02/07/2023]
Abstract
The central nervous system develops around a fluid filled space which persists in the adult within the ventricles, spinal canal and around the outside of the brain and spinal cord. Ventricular fluid is known to act as a growth medium and stimulator of proliferation and differentiation to neural stem cells but the role of CSF in the subarachnoid space has not been fully investigated except for its role in the recently described "glymphatic" system. Fundamental changes occur in the control and coordination of CNS development upon completion of brain stem and spinal cord development and initiation of cortical development. These include changes in gene expression, changes in fluid and fluid source from neural tube fluid to cerebrospinal fluid (CSF), changes in fluid volume, composition and fluid flow pathway, with exit of high volume CSF into the subarachnoid space and the critical need for fluid drainage. We used a number of experimental approaches to test a predicted critical role for CSF in development of the cerebral cortex in rodents and humans. Data from fetuses affected by spina bifida and/or hydrocephalus are correlated with experimental evidence on proliferation and migration of cortical cells from the germinal epithelium in rodent neural tube defects, as well as embryonic brain slice experiments demonstrating a requirement for CSF to contact both ventricular and pial surfaces of the developing cortex for normal proliferation and migration. We discuss the possibility that complications with the fluid system are likely to underlie developmental disorders affecting the cerebral cortex as well as function and integrity of the cortex throughout life.
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26
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Wostyn P, De Deyn PP. The retinal nerve fiber layer as a window to the glymphatic system. Clin Neurol Neurosurg 2019; 188:105593. [PMID: 31756617 DOI: 10.1016/j.clineuro.2019.105593] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/30/2019] [Accepted: 11/09/2019] [Indexed: 11/17/2022]
Affiliation(s)
- Peter Wostyn
- Department of Psychiatry, PC Sint-Amandus, Reigerlostraat 10, 8730 Beernem, Belgium.
| | - Peter Paul De Deyn
- Department of Biomedical Sciences, Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium; Department of Neurology and Alzheimer Research Center, University of Groningen and University Medical Center Groningen, Hanzeplein 1, 9700 RB Groningen, the Netherlands; Department of Neurology and Memory Clinic, Middelheim General Hospital (ZNA), Lindendreef 1, 2020 Antwerp, Belgium
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27
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Tamura R, Yoshida K, Toda M. Current understanding of lymphatic vessels in the central nervous system. Neurosurg Rev 2019; 43:1055-1064. [PMID: 31209659 DOI: 10.1007/s10143-019-01133-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 04/29/2019] [Accepted: 06/05/2019] [Indexed: 12/18/2022]
Abstract
Lymphangiogenesis is associated with some pathological conditions such as inflammation, tissue repair, and tumor growth. Recently, a paradigm shift occurred following the discovery of meningeal lymphatic structures in the human central nervous system (CNS); these structures may be a key drainage route for cerebrospinal fluid (CSF) into the peripheral blood and may also contribute to inflammatory reaction and immune surveillance of the CNS. Lymphatic vessels located along the dural sinuses absorb CSF from the adjacent subarachnoid space and brain interstitial fluid via the glymphatic system, which is composed of aquaporin-4 water channels expressed on perivascular astrocytic end-feet membranes. Magnetic resonance imaging (MRI) clearly visualized these lymphatic vessels in the human dura mater. The conception of some neurological disorders, such as multiple sclerosis and Alzheimer's disease, has been changed by this paradigm shift. Meningeal lymphatic vessels could be a promising therapeutic target for the prevention of neurological disorders. However, the involvement of meningeal lymphatic vessels in the pathophysiology has not been fully elucidated and is the subject of future investigations. In this article, to understand the involvement of meningeal lymphatic vessels in neurological disorders, we review the differences between lymphangiogenesis in the CNS and in other tissues during both developmental and adulthood stages, and pathological conditions that may be associated with meningeal lymphatic vessels in the CNS.
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Affiliation(s)
- Ryota Tamura
- Department of Neurosurgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Kazunari Yoshida
- Department of Neurosurgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Masahiro Toda
- Department of Neurosurgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.
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28
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Mathieu E, Gupta N, Paczka-Giorgi LA, Zhou X, Ahari A, Lani R, Hanna J, Yücel YH. Reduced Cerebrospinal Fluid Inflow to the Optic Nerve in Glaucoma. Invest Ophthalmol Vis Sci 2019; 59:5876-5884. [PMID: 30543343 DOI: 10.1167/iovs.18-24521] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To determine whether cerebrospinal fluid (CSF) entry into the optic nerve is altered in glaucoma. Methods Fluorescent 10-kDa dextran tracer was injected into the CSF of 2-month-old (n = 9) and 10-month-old DBA/2J glaucoma mice (n = 8) and age-matched controls (C57Bl/6; n = 8 each group). Intraocular pressure (IOP) was measured in all mice before tracer injection into CSF. Tracer distribution was assessed using confocal microscopy of optic nerve cross-sections of mice killed 1 hour after injection. Paravascular tracer distribution in the optic nerve was studied in relation to isolectin-stained blood vessels. Tracer intensity and cross-sectional area in the laminar optic nerve were quantitatively assessed in all four groups and statistically compared. Aquaporin 4 (AQP4) and retinal ganglion cell axonal phosphorylated neurofilament (pNF) were evaluated using immunofluorescence and confocal microscopy. Results IOP was elevated in 10-month-old glaucoma mice compared with age-matched controls. One hour after tracer injection, controls showed abundant CSF tracer in the optic nerve subarachnoid space and within the nerve in paravascular spaces surrounding isolectin-labeled blood vessels. CSF tracer intensity and signal distribution in the optic nerve were significantly decreased in 10-month-old glaucoma mice compared with age-matched controls (P = 0.0008 and P = 0.0033, respectively). AQP4 immunoreactivity was similar in 10-month-old DBA and age-matched control mice. Half of the 10-month-old DBA mice (n = 4/8) showed a decrease in pNF immunoreactivity compared to controls. Altered pNF staining was seen only in DBA mice lacking CSF tracer at the laminar optic nerve (n = 4/5). Conclusions This study provides the first evidence that CSF entry into the optic nerve is impaired in glaucoma. This finding points to a novel CSF-related mechanism that may help to understand optic nerve damage in glaucoma.
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Affiliation(s)
- Emily Mathieu
- Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.,Department of Laboratory Medicine and Pathobiology, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Neeru Gupta
- Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.,Department of Laboratory Medicine and Pathobiology, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.,Glaucoma Unit, St. Michael's Hospital, Toronto, Ontario, Canada.,Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Luz A Paczka-Giorgi
- Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Xun Zhou
- Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Amir Ahari
- Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Rafael Lani
- Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Joseph Hanna
- Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.,Department of Laboratory Medicine and Pathobiology, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Yeni H Yücel
- Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Sciences, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.,Department of Laboratory Medicine and Pathobiology, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.,Department of Physics, Faculty of Science, Ryerson University, Toronto, Ontario, Canada.,Faculty of Engineering and Architectural Science, Ryerson University, Toronto, Ontario, Canada.,Institute of Biomedical Engineering, Science and Technology (iBEST), St. Michael's Hospital, Ryerson University, Toronto, Ontario, Canada
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29
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Tsutsumi S, Ono H, Ishii H, Yasumoto Y. Interdural high signal on CISS sequence: an alternative CSF pathway? Childs Nerv Syst 2019; 35:487-491. [PMID: 30613855 DOI: 10.1007/s00381-018-04044-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 12/28/2018] [Indexed: 10/27/2022]
Abstract
PURPOSE The falx cerebri, falx cerebelli, and tentorial notch exhibit a peculiar morphology with a two-layered, dural leaf that protrudes into the cranial cavity with a free edge. However, there are few studies exploring this morphology using neuroimaging techniques. The present study aimed to explore these dural structures using magnetic resonance imaging. METHODS A total of 65 outpatients were included in this study. Following initial examinations with conventional sequences, the constructive interference in steady-state (CISS) sequences were performed in thin-sliced, coronal sections. RESULTS In 78% of the subjects, the interdural spaces presenting with high signal were identified in the falx cerebri. These spaces were located adjacent to the uppermost part of the falx, formed by two dural leaves and the superior sagittal sinus, and tapered downward where the leaves united to form the falx cerebri. At the tentorial notch, these spaces were found in 52% of the 65, most predominantly in the medial edge followed by the tentorium cerebelli-tentorial notch junctional region. Forty-one percent of patients had a dural opening into the cerebral cistern. The interdural spaces with high signal were not identified in the tentorium cerebelli in any of the subjects. CONCLUSIONS The falx cerebri and tentorial notch form the interdural spaces that may provide alternative cerebrospinal fluid pathways. The coronal CISS sequence is suitable for delineating such interdural spaces.
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Affiliation(s)
- Satoshi Tsutsumi
- Department of Neurological Surgery, Juntendo University Urayasu Hospital, 2-1-1 Tomioka, Urayasu, Chiba, 279-0021, Japan.
| | - Hideo Ono
- Division of Radiological Technology, Medical Satellite Yaesu Clinic, Tokyo, Japan
| | - Hisato Ishii
- Department of Neurological Surgery, Juntendo University Urayasu Hospital, 2-1-1 Tomioka, Urayasu, Chiba, 279-0021, Japan
| | - Yukimasa Yasumoto
- Department of Neurological Surgery, Juntendo University Urayasu Hospital, 2-1-1 Tomioka, Urayasu, Chiba, 279-0021, Japan
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30
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Breslin JW, Yang Y, Scallan JP, Sweat RS, Adderley SP, Murfee WL. Lymphatic Vessel Network Structure and Physiology. Compr Physiol 2018; 9:207-299. [PMID: 30549020 PMCID: PMC6459625 DOI: 10.1002/cphy.c180015] [Citation(s) in RCA: 174] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The lymphatic system is comprised of a network of vessels interrelated with lymphoid tissue, which has the holistic function to maintain the local physiologic environment for every cell in all tissues of the body. The lymphatic system maintains extracellular fluid homeostasis favorable for optimal tissue function, removing substances that arise due to metabolism or cell death, and optimizing immunity against bacteria, viruses, parasites, and other antigens. This article provides a comprehensive review of important findings over the past century along with recent advances in the understanding of the anatomy and physiology of lymphatic vessels, including tissue/organ specificity, development, mechanisms of lymph formation and transport, lymphangiogenesis, and the roles of lymphatics in disease. © 2019 American Physiological Society. Compr Physiol 9:207-299, 2019.
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Affiliation(s)
- Jerome W. Breslin
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - Ying Yang
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - Joshua P. Scallan
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - Richard S. Sweat
- Department of Biomedical Engineering, Tulane University, New Orleans, LA
| | - Shaquria P. Adderley
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - W. Lee Murfee
- Department of Biomedical Engineering, University of Florida, Gainesville, FL
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31
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Pircher A, Montali M, Wostyn P, Pircher J, Berberat J, Remonda L, Killer HE. Impaired cerebrospinal fluid dynamics along the entire optic nerve in normal-tension glaucoma. Acta Ophthalmol 2018. [PMID: 29532640 DOI: 10.1111/aos.13647] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
PURPOSE To investigate the cerebrospinal fluid (CSF) dynamics along the entire optic nerve (ON) in patients with normal-tension glaucoma (NTG). METHODS Retrospective analysis of computed tomographic (CT) cisternographies in Caucasian patients with NTG. Fifty-six patients (99 of 112 eyes) fulfilled the diagnostic criteria of NTG and underwent CT-cisternography. Twelve subjects without NTG (24 eyes) served as controls. Contrast-loaded cerebrospinal fluid (CLCSF) density measurements in Hounsfield units (HU) were performed at four defined regions along the ON and in the basal cistern. RESULTS In NTG patients, the mean density CLCSF in the bulbar segment measured 76 ± 49 HU right and 88 ± 74 HU left, in the mid-orbital segment 117 ± 92 HU right and 119 ± 73 HU left, in the intracanalicular ON portion 209 ± 88 HU right and 216 ± 101 HU left, in the intracranial ON portion 290 ± 106 HU right and 286 ± 118 HU left and in the basal cistern 517 ± 213 HU. The distribution of CLCSF along the ON showed a statistically significant reduction in the intraorbital ON segments in NTG patients compared to controls without NTG with the far largest difference within the retrobulbar segment (-150 HU right and -117 HU left; right: p < 0.001, left: p < 0.001). CONCLUSION This study demonstrates a gradual reduction in CLCSF towards the retrobulbar segment in NTG, while in controls without NTG, no reduction in CLCSF was measured within the orbital segments. Impaired CSF dynamics along the ON may contribute to the pathophysiology of NTG.
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Affiliation(s)
| | - Margherita Montali
- Ophthalmology; Cantonal Hospital; Aarau Switzerland
- Neuroradiology; Cantonal Hospital; Aarau Switzerland
| | - Peter Wostyn
- Department of Psychiatry; PC Sint-Amandus; Beernem Belgium
| | - Joachim Pircher
- Medizinische Klinik und Poliklinik I; Ludwig-Maximilians-University; Munich Germany
| | | | - Luca Remonda
- Neuroradiology; Cantonal Hospital; Aarau Switzerland
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32
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Lymphatic drainage of cerebrospinal fluid in mammals - are arachnoid granulations the main route of cerebrospinal fluid outflow? Biologia (Bratisl) 2018; 73:563-568. [PMID: 30147112 PMCID: PMC6097054 DOI: 10.2478/s11756-018-0074-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 05/18/2018] [Indexed: 11/26/2022]
Abstract
The outflow of the cerebrospinal fluid (CSF) in animals was over the years the subject of detailed analysis. For a long time it was stated that arachnoid granulations of the venous sinuses play a key role in CSF circulation. However, recent studies on this subject have shown that a considerable part of the CSF is drained to the lymphatic vessels. Moreover, disorders in the CSF passage may result in severe central nervous system diseases such as e.g. hydrocephalus. In this paper, we summarize the current knowledge concerning the lymphatic drainage of the CSF in mammals. We present in detail comparative anatomy of different species taking into account cranial and spinal compartment. In addition, we clarified role of the lymphatic vessels in the CSF outflow and the relationship between impairment in this transport and central nervous system diseases. In the author’s opinion knowledge on CSF circulation is still poorly examined and therefore required comment.
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33
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Trost A, Runge C, Bruckner D, Kaser-Eichberger A, Bogner B, Strohmaier C, Reitsamer HA, Schroedl F. Lymphatic markers in the human optic nerve. Exp Eye Res 2018; 173:113-120. [PMID: 29746818 DOI: 10.1016/j.exer.2018.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/25/2018] [Accepted: 05/05/2018] [Indexed: 12/20/2022]
Abstract
Tissues of the central nervous system (CNS), including the optic nerve (ON), are considered a-lymphatic. However, lymphatic structures have been described in the dura mater of human ON sheaths. Since it is known that lymphatic markers are also expressed by single non-lymphatic cells, these results need confirmation according to the consensus statement for the use of lymphatic markers in ophthalmologic research. The aim of this study was to screen for the presence of lymphatic structures in the adult human ON using a combination of four lymphatic markers. Cross and longitudinal cryo-sections of human optic nerve tissue (n = 12, male and female, postmortem time = 15.8 ± 5.5 h, age = 66.5 ± 13.8 years), were obtained from cornea donors of the Salzburg eye bank, and analyzed using immunofluorescence with the following markers: FOXC2, CCL21, LYVE-1 and podoplanin (PDPN; lymphatic markers), Iba1 (microglia), CD68 (macrophages), CD31 (endothelial cell, EC), NF200 (neurofilament), as well as GFAP (astrocytes). Human skin sections served as positive controls and confocal microscopy in single optical section mode was used for documentation. In human skin, lymphatic structures were detected, showing a co-localization of LYVE-1/PDPN/FOXC2 and CCL21/LYVE-1. In the human ON however, single LYVE-1+ cells were detected, but were not co-localized with any other lymphatic marker tested. Instead, LYVE-1+ cells displayed immunopositivity for Iba1 and CD68, being more pronounced in the periphery of the ON than in the central region. However, Iba1+/LYVE-1- cells outnumbered Iba1+/LYVE-1+ cells. PDPN, revealed faint labeling in human ON tissue despite strong immunoreactivity in rat ON controls, showing co-localization with GFAP in the periphery. In addition, pronounced autofluorescent dots were detected in the ON, showing inter-individual differences in numbers. In the adult human ON no lymphatic structures were detected, although distinct lymphatic structures were identified in human skin tissue by co-localization of four lymphatic markers. However, single LYVE-1+ cells, also positive for Iba1 and CD68 were present, indicating LYVE-1+ macrophages. Inter-individual differences in the number of LYVE-1+ as well as Iba1+ cells were obvious within the ONs, most likely resulting from diverse medical histories of the donors.
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Affiliation(s)
- A Trost
- Dept Ophthalmology/Optometry, Research Program Experimental Ophthalmology, Paracelsus Medical University Salzburg, Austria.
| | - C Runge
- Dept Ophthalmology/Optometry, Research Program Experimental Ophthalmology, Paracelsus Medical University Salzburg, Austria
| | - D Bruckner
- Dept Ophthalmology/Optometry, Research Program Experimental Ophthalmology, Paracelsus Medical University Salzburg, Austria
| | - A Kaser-Eichberger
- Dept Ophthalmology/Optometry, Research Program Experimental Ophthalmology, Paracelsus Medical University Salzburg, Austria
| | - B Bogner
- Dept Ophthalmology/Optometry, Research Program Experimental Ophthalmology, Paracelsus Medical University Salzburg, Austria
| | - C Strohmaier
- Dept Ophthalmology/Optometry, Research Program Experimental Ophthalmology, Paracelsus Medical University Salzburg, Austria
| | - H A Reitsamer
- Dept Ophthalmology/Optometry, Research Program Experimental Ophthalmology, Paracelsus Medical University Salzburg, Austria; Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Austria
| | - F Schroedl
- Dept Ophthalmology/Optometry, Research Program Experimental Ophthalmology, Paracelsus Medical University Salzburg, Austria; Department of Anatomy, Paracelsus Medical University Salzburg, Austria
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Eide PK, Vatnehol SAS, Emblem KE, Ringstad G. Magnetic resonance imaging provides evidence of glymphatic drainage from human brain to cervical lymph nodes. Sci Rep 2018; 8:7194. [PMID: 29740121 PMCID: PMC5940793 DOI: 10.1038/s41598-018-25666-4] [Citation(s) in RCA: 174] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 04/26/2018] [Indexed: 12/12/2022] Open
Abstract
Pre-clinical research in rodents provides evidence that the central nervous system (CNS) has functional lymphatic vessels. In-vivo observations in humans, however, are not demonstrated. We here show data on CNS lymphatic drainage to cervical lymph nodes in-vivo by magnetic resonance imaging (MRI) enhanced with an intrathecal contrast agent as a cerebrospinal fluid (CSF) tracer. Standardized MRI of the intracranial compartment and the neck were acquired before and up to 24–48 hours following intrathecal contrast agent administration in 19 individuals. Contrast enhancement was radiologically confirmed by signal changes in CSF nearby inferior frontal gyrus, brain parenchyma of inferior frontal gyrus, parahippocampal gyrus, thalamus and pons, and parenchyma of cervical lymph node, and with sagittal sinus and neck muscle serving as reference tissue for cranial and neck MRI acquisitions, respectively. Time series of changes in signal intensity shows that contrast enhancement within CSF precedes glymphatic enhancement and peaks at 4–6 hours following intrathecal injection. Cervical lymph node enhancement coincides in time with peak glymphatic enhancement, with peak after 24 hours. Our findings provide in-vivo evidence of CSF tracer drainage to cervical lymph nodes in humans. The time course of lymph node enhancement coincided with brain glymphatic enhancement rather than with CSF enhancement.
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Affiliation(s)
- Per Kristian Eide
- Department of Neurosurgery, Oslo University Hospital-Rikshospitalet, Oslo, Norway. .,Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.
| | - Svein Are Sirirud Vatnehol
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,The Intervention Centre, Oslo University Hospital, Oslo, Norway
| | - Kyrre Eeg Emblem
- The Intervention Centre, Oslo University Hospital, Oslo, Norway.,Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway
| | - Geir Ringstad
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Radiology and Nuclear Medicine, Oslo University Hospital - Rikshospitalet, Oslo, Norway
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Zhang LF, Hargens AR. Spaceflight-Induced Intracranial Hypertension and Visual Impairment: Pathophysiology and Countermeasures. Physiol Rev 2017; 98:59-87. [PMID: 29167331 DOI: 10.1152/physrev.00017.2016] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 05/25/2017] [Accepted: 05/26/2017] [Indexed: 12/21/2022] Open
Abstract
Visual impairment intracranial pressure (VIIP) syndrome is considered an unexplained major risk for future long-duration spaceflight. NASA recently redefined this syndrome as Spaceflight-Associated Neuro-ocular Syndrome (SANS). Evidence thus reviewed supports that chronic, mildly elevated intracranial pressure (ICP) in space (as opposed to more variable ICP with posture and activity on Earth) is largely accounted for by loss of hydrostatic pressures and altered hemodynamics in the intracranial circulation and the cerebrospinal fluid system. In space, an elevated pressure gradient across the lamina cribrosa, caused by a chronic but mildly elevated ICP, likely elicits adaptations of multiple structures and fluid systems in the eye which manifest themselves as the VIIP syndrome. A chronic mismatch between ICP and intraocular pressure (IOP) in space may acclimate the optic nerve head, lamina cribrosa, and optic nerve subarachnoid space to a condition that is maladaptive to Earth, all contributing to the pathogenesis of space VIIP syndrome. Relevant findings help to evaluate whether artificial gravity is an appropriate countermeasure to prevent this seemingly adverse effect of long-duration spaceflight.
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Affiliation(s)
- Li-Fan Zhang
- Department of Aerospace Physiology, Fourth Military Medical University, Xi'an, China; and Department of Orthopaedic Surgery, University of California, San Diego, California
| | - Alan R Hargens
- Department of Aerospace Physiology, Fourth Military Medical University, Xi'an, China; and Department of Orthopaedic Surgery, University of California, San Diego, California
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Ma Q, Ineichen BV, Detmar M, Proulx ST. Outflow of cerebrospinal fluid is predominantly through lymphatic vessels and is reduced in aged mice. Nat Commun 2017; 8:1434. [PMID: 29127332 PMCID: PMC5681558 DOI: 10.1038/s41467-017-01484-6] [Citation(s) in RCA: 411] [Impact Index Per Article: 58.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 09/18/2017] [Indexed: 11/09/2022] Open
Abstract
Cerebrospinal fluid (CSF) has been commonly accepted to drain through arachnoid projections from the subarachnoid space to the dural venous sinuses. However, a lymphatic component to CSF outflow has long been known. Here, we utilize lymphatic-reporter mice and high-resolution stereomicroscopy to characterize the anatomical routes and dynamics of outflow of CSF. After infusion into a lateral ventricle, tracers spread into the paravascular spaces of the pia mater and cortex of the brain. Tracers also rapidly reach lymph nodes using perineural routes through foramina in the skull. Using noninvasive imaging techniques that can quantify the transport of tracers to the blood and lymph nodes, we find that lymphatic vessels are the major outflow pathway for both large and small molecular tracers in mice. A significant decline in CSF lymphatic outflow is found in aged compared to young mice, suggesting that the lymphatic system may represent a target for age-associated neurological conditions.
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Affiliation(s)
- Qiaoli Ma
- Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology, ETH Zurich, 8093, Zurich, Switzerland
| | | | - Michael Detmar
- Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology, ETH Zurich, 8093, Zurich, Switzerland
| | - Steven T Proulx
- Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology, ETH Zurich, 8093, Zurich, Switzerland.
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Intraocular Silicone Oil Migration into the Ventricles Resembling Intraventricular Hemorrhage: Case Report and Review of the Literature. World Neurosurg 2017; 102:695.e7-695.e10. [DOI: 10.1016/j.wneu.2017.03.131] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 03/25/2017] [Accepted: 03/27/2017] [Indexed: 02/07/2023]
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Lohrberg M, Wilting J. The lymphatic vascular system of the mouse head. Cell Tissue Res 2016; 366:667-677. [PMID: 27599481 PMCID: PMC5121175 DOI: 10.1007/s00441-016-2493-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 08/15/2016] [Indexed: 12/25/2022]
Abstract
Histological studies of the lymphatic vascular system in adult mice are hampered because bones cannot be sectioned properly. Here, we decalcified the heads of 14-day-old mice, embedded them in paraffin and stained resultant serial sections with the lymphendothelial-specific antibodies Lyve-1 and Podoplanin. We show that the tissues with the highest lymphatic vascular density are the dermis and the oral mucous membranes. In contrast, the nasal mucous membrane is devoid of lymphatics, except for its most basal parts below the vomeronasal organ. The inferior nasal turbinate contains numerous lymphatics and is connected to the nasolacrimal duct (NLD), which is ensheathed by a dense network of lymphatics. The lymphatics of the eye lids and conjunctiva are connected to those of the inferior nasal turbinate. We suggest that cerebro-spinal fluid (CSF) can drain via the optic nerve and NLD lymphatics, whereas CSF drained via the Fila olfactoria into the nasal mucous membrane is used for moisturization of the respiratory air. Tongue, palatine and buccal mucous membranes possess numerous lymphatics, whereas the dental pulp has none. Lymphatics are present in the maxillary gland and close to the temporomandibular joint, suggesting the augmentation of lymph flow by chewing and yawning. Lymphatics can also be found in the dura mater and in the dural septae entering into deeper parts of the brain. Our findings are discussed with regard to CSF drainage and potential routes for ocular tumor dissemination.
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Affiliation(s)
- Melanie Lohrberg
- Department of Anatomy and Cell Biology, University Medical School Göttingen, Göttingen, Germany.
| | - Jörg Wilting
- Department of Anatomy and Cell Biology, University Medical School Göttingen, Göttingen, Germany
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Roth C, Stitz H, Roth C, Ferbert A, Deinsberger W, Pahl R, Engel H, Kleffmann J. Craniocervical manual lymphatic drainage and its impact on intracranial pressure - a pilot study. Eur J Neurol 2016; 23:1441-6. [PMID: 27238738 DOI: 10.1111/ene.13055] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 04/21/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND PURPOSE Theoretical considerations and the results of animal studies indicate that manual lymphatic drainage (MLD) might have an impact on intracranial pressure (ICP). There is a lack of clinically qualitative investigations on patients with severe cerebral diseases. METHODS Between April 2013 and January 2015 a prospective observational study was performed on patients who were undergoing intracranial pressure measurement and treatment with MLD. ICP, cerebral perfusion pressure, mean arterial pressure (MAP), heart rate and oxygen saturation were recorded continuously 15 min before the procedure, during MLD (22 min) and for 15 min after the procedure. For analysis the data treatment units were divided into two groups: patients with a mean baseline ICP <15 mmHg (group 1) and patients with a mean ICP ≥15 mmHg before MLD (group 2). RESULTS A total of 133 treatment units (61 patients) were analysed (group 1 n = 99; group 2 n = 34). The mean baseline ICP was 10.4 mmHg overall, and 8.3 mmHg and 18.6 mmHg respectively in group 1 and group 2; ICP significantly decreased during therapy with MLD and this persisted during the follow-up period in group 2. MAP did not show any significant differences between the different periods. CONCLUSIONS Our data showed a significant reduction of ICP during therapy with craniocervical MLD in patients with severe cerebral diseases.
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Affiliation(s)
- C Roth
- Department of Neurology, Klinikum Kassel, Kassel, Germany
| | - H Stitz
- Department of Physiotherapy, Klinikum Kassel, Kassel, Germany
| | - C Roth
- Department of Physiotherapy, Klinikum Kassel, Kassel, Germany
| | - A Ferbert
- Department of Neurology, Klinikum Kassel, Kassel, Germany
| | - W Deinsberger
- Department of Neurosurgery, Klinikum Kassel, Kassel, Germany
| | - R Pahl
- Institute of Medical Biometry and Epidemiology (IMBE), Philipps University Marburg, Marburg, Germany
| | - H Engel
- Department of Hand, Plastic and Reconstructive Surgery, Klinikum Kassel, Kassel, Germany
| | - J Kleffmann
- Department of Neurosurgery, Klinikum Kassel, Kassel, Germany
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Hou R, Zhang Z, Yang D, Wang H, Chen W, Li Z, Sang J, Liu S, Cao Y, Xie X, Ren R, Zhang Y, Sabel BA, Wang N. Intracranial pressure (ICP) and optic nerve subarachnoid space pressure (ONSP) correlation in the optic nerve chamber: the Beijing Intracranial and Intraocular Pressure (iCOP) study. Brain Res 2016; 1635:201-8. [PMID: 26794252 DOI: 10.1016/j.brainres.2016.01.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 01/06/2016] [Accepted: 01/07/2016] [Indexed: 10/22/2022]
Abstract
PURPOSE Because a lowered intracranial pressure (ICP) is a possible mechanism of optic neuropathy, we wished to study the CSF dynamics in the optic nerve chamber by recording possible changes in the optic nerve subarachnoid space pressure (ONSP) and the impact on it when acutely lowering ICP. METHODS In eight normal dogs pressure probes were implanted in the left brain ventricle, lumbar cistern, optic nerve subarachnoid space and in the anterior eye chamber. Following CSF shunting from the brain ventricle we monitored changes of ICP, lumbar cistern pressure (LCP), ONSP and intraocular pressure (IOP). RESULTS At baseline, the pressures were different with ICP>LCP>ONSP but correlated with each other (P<0.001). The "trans-lamina cribrosa pressure gradient" (TLPG) was highest for IOP-ONSP, lower for IOP-LCP, and lowest for IOP-ICP (P<0.001). During CSF shunting the ICP gradually decreased in a linear fashion together with the ONSP ("ICP-depended zone"). But when the ICP fell below a critical breakpoint, ICP and ONSP became uncoupled and ONSP remained constant despite further ICP decline ("ICP-independent zone"). CONCLUSIONS Because the parallel decline of ICP and ONSP breaks down when ICP decreases below a critical breakpoint, we interpret this as a sign of CSF communication arrest between the intracranial and optic nerve SAS. This may be caused by obstructions of either CSF inflow through the optic canal or outflow into the intra-orbital cavity. This CSF exchange arrest may be a contributing factor to optic nerve damage and the optic nerve chamber syndrome which may influence the loss of vision or its restoration.
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Affiliation(s)
- Ruowu Hou
- Department of Neurosurgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Zheng Zhang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China
| | - Diya Yang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China; Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Huaizhou Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China; Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Weiwei Chen
- Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Zhen Li
- Department of Ophthalmology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Jinghong Sang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China
| | - Sumeng Liu
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China
| | - Yiwen Cao
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China
| | - Xiaobin Xie
- Department of Ophthalmology, Eye Hospital of China Academy of Chinese Medical Sciences, Beijing, China
| | - Ruojin Ren
- Eye center, New York Eye and Ear Infirmary, NY, USA
| | - Yazhuo Zhang
- Department of Endoscopic and Microinvasive Neurosugery, Beijing Neurosurgery Institute, Beijing Tiantian Hospital, Capital Medical University, Beijing, China.
| | - Bernhard A Sabel
- Institute of Medical Psychology, Medical Faculty, Otto-v.-Guericke University of Magdeburg, Magdeburg, Germany
| | - Ningli Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China; Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
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Raybaud C. MR assessment of pediatric hydrocephalus: a road map. Childs Nerv Syst 2016; 32:19-41. [PMID: 26337698 DOI: 10.1007/s00381-015-2888-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 08/11/2015] [Indexed: 12/12/2022]
Abstract
PURPOSE This study was conducted to design a rational approach to the MR diagnosis of hydrocephalus based on a pathophysiologic reevaluation of its possible mechanisms and to apply it to the different etiological contexts. METHOD A review of the literature reports describing new physiologic models of production and absorption and of the hydrodynamics of the CSF was made. RESULTS Besides the secretion of CSF by the choroid plexuses, and its passive, pressure-dependent transdural absorption (arachnoid villi, dural clefts, cranial, and spinal nerve sheaths), water transporters, aquaporins, allow water (if not ions and organic molecules) to exchange freely between the brain parenchyma and the CSF spaces across the ependymal and the pial interfaces (including the Virchow-Robin spaces). Consequently, the CSF bulk flow is not necessarily global, and situations of balanced absorption-secretion may occur separately in different CSF compartments such as the ventricular, intracranial, or intraspinal CSF spaces. This means that rather than from a hypothetical pressure gradient from the plexuses to the dural sinuses, the dynamics of the CSF depend on the force provided in those different compartments by the arterial systolic pulsation of the pericerebral (mostly), intracerebral, and intraventricular (choroid plexuses) vascular beds. CONCLUSION Using MR imaging, diverse varieties of hydrocephalus may tentatively be explained by applying those concepts to the correspondingly diverse causal diseases. Hopefully, this may have an impact on the choice of the treatment strategies also.
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Affiliation(s)
- Charles Raybaud
- Division of Neuroradiology, Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON, M5G 1X8, Canada.
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Morgan WH, Balaratnasingam C, Lind CRP, Colley S, Kang MH, House PH, Yu DY. Cerebrospinal fluid pressure and the eye. Br J Ophthalmol 2015; 100:71-7. [DOI: 10.1136/bjophthalmol-2015-306705] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 03/22/2015] [Indexed: 11/04/2022]
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Oi S. Hydrocephalus research update--controversies in definition and classification of hydrocephalus. Neurol Med Chir (Tokyo) 2013; 50:859-69. [PMID: 20885121 DOI: 10.2176/nmc.50.859] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Classification of hydrocephalus is the most crucial but the most complicated academic challenge within the hydrocephalus research field. The major difficulty in this challenge arises from the fact that the classification is based on almost all subjects in hydrocephalus research, i.e., definition and terminology of hydrocephalus, pathophysiology, hydrocephalus chronology, specific forms of hydrocephalus, associated congenital anomalies/syndrome and underlying conditions, diagnostic procedures for hydrocephalus, and treatment modalities in hydrocephalus. The current status of the classification of hydrocephalus in individual subgroups was reviewed and summarized from publications in the last 60 years (1950-2010), and discussed focusing on the variety of characteristics in hydrocephalus, with more and more new aspects recently disclosed not only in fetal and pediatric but also in adult hydrocephalus. A recently-reported classification of hydrocephalus, "Multi-categorical Hydrocephalus Classification" provides comprehensive coverage of the entire aspects of hydrocephalus with current important classification categories and subtypes.
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Affiliation(s)
- Shizuo Oi
- Department of Neurosurgery, The Jikei University School of Medicine, 3-25-8 Nishi Shinbashi, Tokyo, Japan.
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Complex Orbital Angiomyoma With Features of a Lymphangiohemangioma. Ophthalmic Plast Reconstr Surg 2013; 29:e61-5. [DOI: 10.1097/iop.0b013e31826b777d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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A perspective from magnetic resonance imaging findings of the inner ear: Relationships among cerebrospinal, ocular and inner ear fluids. Auris Nasus Larynx 2012; 39:345-55. [DOI: 10.1016/j.anl.2011.05.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2011] [Revised: 05/06/2011] [Accepted: 05/17/2011] [Indexed: 02/06/2023]
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Oi S. Classification of hydrocephalus: critical analysis of classification categories and advantages of "Multi-categorical Hydrocephalus Classification" (Mc HC). Childs Nerv Syst 2011; 27:1523-33. [PMID: 21928018 DOI: 10.1007/s00381-011-1542-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2011] [Accepted: 07/25/2011] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Hydrocephalus is a complex pathophysiology with disturbed cerebrospinal fluid (CSF) circulation. There are numerous numbers of classification trials published focusing on various criteria, such as associated anomalies/underlying lesions, CSF circulation/intracranial pressure patterns, clinical features, and other categories. However, no definitive classification exists comprehensively to cover the variety of these aspects. The new classification of hydrocephalus, "Multi-categorical Hydrocephalus Classification" (Mc HC), was invented and developed to cover the entire aspects of hydrocephalus with all considerable classification items and categories. MATERIALS AND METHOD Ten categories include "Mc HC" category I: onset (age, phase), II: cause, III: underlying lesion, IV: symptomatology, V: pathophysiology 1-CSF circulation, VI: pathophysiology 2-ICP dynamics, VII: chronology, VII: post-shunt, VIII: post-endoscopic third ventriculostomy, and X: others. From a 100-year search of publication related to the classification of hydrocephalus, 14 representative publications were reviewed and divided into the 10 categories. RESULTS AND DISCUSSION The Baumkuchen classification graph made from the round o'clock classification demonstrated the historical tendency of deviation to the categories in pathophysiology, either CSF or ICP dynamics. CONCLUSION In the preliminary clinical application, it was concluded that "Mc HC" is extremely effective in expressing the individual state with various categories in the past and present condition or among the compatible cases of hydrocephalus along with the possible chronological change in the future.
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Affiliation(s)
- Shizuo Oi
- Health Sciences Asia Executive Dean Office, Japan International University, 2-18-1 Nakoji, Amagasaki, Hyogo 661-8530, Japan.
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Feng CY, Wiggins LM, von Bartheld CS. The locus ceruleus responds to signaling molecules obtained from the CSF by transfer through tanycytes. J Neurosci 2011; 31:9147-58. [PMID: 21697366 PMCID: PMC4050199 DOI: 10.1523/jneurosci.5018-10.2011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 05/02/2011] [Accepted: 05/04/2011] [Indexed: 12/15/2022] Open
Abstract
Neurons can access signaling molecules through two principal pathways: synaptic transmission ("wiring transmission") and nonsynaptic transmission ("volume transmission"). Wiring transmission is usually considered the far more important mode of neuronal signaling. Using embryonic chick locus ceruleus (LoC) as a model, we quantified and compared routes of delivery of the neurotrophin nerve growth factor (NGF), either through a multisynaptic axonal pathway or via the CSF. We now show that the axonal pathway from the eye to the LoC involves axo-axonic transfer of NGF with receptor switching (p75 to trkA) in the optic tectum. In addition to the axonal pathway, the LoC of chick embryos has privileged access to the CSF through a specialized glial/ependymal cell type, the tanycyte. The avian LoC internalizes from the CSF in a highly specific fashion both NGF and the hormone urotensin (corticotropin-releasing factor family ligand). Quantitative autoradiography at the ultrastructural level shows that tanycytes transcytose and deliver NGF to LoC neurons via synaptoid contacts. The LoC-associated tanycytes express both p75 and trkA receptors. The NGF extracted by tanycytes from the CSF has physiological effects on LoC neurons, as evidenced by significantly altered nuclear diameters in both gain-of-function and loss-of-function experiments. Quantification of NGF extraction shows that, compared with multisynaptic axonal routes of NGF trafficking to LoC, the tanycyte route is significantly more effective. We conclude that some clinically important neuronal populations such as the LoC can use a highly efficient "back door" interface to the CSF and can receive signals via this tanycyte-controlled pathway.
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Affiliation(s)
- Cheng-Yuan Feng
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada 89557
| | - Larisa M. Wiggins
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada 89557
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Endoscopic orbital roof fenestration as an alternative treatment option for idiopathic intracranial hypertension: a cadaveric anatomical study. J Neuroophthalmol 2010; 31:25-8. [PMID: 20847701 DOI: 10.1097/wno.0b013e3181e8a04e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND We investigated a new minimally invasive surgical technique for the treatment of idiopathic intracranial hypertension in a cadaveric model. This technique aims at establishing a communication between the intraorbital and intracranial compartments by creating a bone, dural, and periorbital window in the anterior cranial fossa. This procedure is predicated on intraorbital absorptive capability that has been demonstrated in animals and discussed in humans. METHODS Three fresh cadaver heads were fixed in a head holder so as to mimic the hyperextended supine position. The procedure was conducted bilaterally in each specimen. Our technique is as follows: 1) An incision is made in the eyebrow medial to the supraorbital notch; 2) using an endoscope and a periosteal elevator, the intraorbital surface of the orbital roof is separated from the periorbita in an anteroposterior direction for a length of 1.5-2.5 cm; 3) a 1 cm of the exposed orbital roof is removed, and the dura and arachnoid are opened; and 4) slits are made in the exposed periorbita. RESULTS We were able to create a communication between the intracranial and the intraorbital compartments in all specimens. CONCLUSION Our technique is new and does not require any foreign body implantation. Its applicability in humans needs to be evaluated in a clinical context.
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50
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Carreras FJ, Porcel D, Guerra-Tschuschke I, Carreras I. Fenestrations and preferential flow routes in the prelaminar optic nerve through wet scanning electron microscope and perfusion of tracers. Clin Exp Ophthalmol 2010; 38:705-17. [PMID: 20497430 DOI: 10.1111/j.1442-9071.2010.02334.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE We study the vitreous interface of the optic disc to delimit the passages for the flow of fluids through the prelaminar tissue of porcine eyes. METHODS Wet scanning electron microscope (SEM), conventional SEM and transmission electron microscope (TEM) were used to explore the surface of the optic nerve of the pig. The vitreous cavity was perfused with a fluorescent marker and colloidal gold at controlled pressure. Samples of perfused optic nerve head were cryosectioned and observed with the confocal laser microscope (lectin) or resin embedded and observed under TEM (gold). RESULTS Fenestrations were present under the SEM in all three regions of the vitreous interface. SEM results were confirmed at the TEM level and under the wet-SEM. Perfusion experiments traced the flow of a fluorescent molecule delineating routes of preferential flow with origin in the fenestrations. Colloidal gold marked the site of entrance in the prelaminar tissue identifying major fenestrations in the basal membrane. CONCLUSIONS Interchange of fluid between the optic nerve and the vitreous cavity in the pig is facilitated by fenestrations of varied sizes in the basal membrane and preferential flow routes through the prelaminar tissue. Preferential flow routes exist in the extracellular spaces of Elschnig and Kuhn' astrocytes and give a sharply distinct image when compared with flow through zones in which astrocytes envelope axons. Escape routes may be instrumental in preventing oedemas of the optic nerve head, but they could also serve as entrance doors for fluids from the vitreous and aqueous and play a pathogenic role in ageing and glaucoma.
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Affiliation(s)
- F Javier Carreras
- Department of Surgery (Ophthalmology), Faculty of Medicine, University of Granada, Granada, Spain.
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