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Arshad N, Biswas N, Gill J, Kesari S, Ashili S. Drug delivery in leptomeningeal disease: Navigating barriers and beyond. Drug Deliv 2024; 31:2375521. [PMID: 38995190 PMCID: PMC11249152 DOI: 10.1080/10717544.2024.2375521] [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: 12/04/2023] [Accepted: 06/27/2024] [Indexed: 07/13/2024] Open
Abstract
Leptomeningeal disease (LMD) refers to the infiltration of cancer cells into the leptomeningeal compartment. Leptomeninges are the two membranous layers, called the arachnoid membrane and pia mater. The diffuse nature of LMD poses a challenge to its effective diagnosis and successful management. Furthermore, the predominant phenotype; solid masses or freely floating cells, has altering implications on the effectiveness of drug delivery systems. The standard of care is the intrathecal delivery of chemotherapy drugs but it is associated with increased instances of treatment-related complications, low patient compliance, and suboptimal drug distribution. An alternative involves administering the drugs systemically, after which they must traverse fluid barriers to arrive at their destination within the leptomeningeal space. However, this route is known to cause off-target effects as well as produce subtherapeutic drug concentrations at the target site within the central nervous system. The development of new drug delivery systems such as liposomal cytarabine has improved drug delivery in leptomeningeal metastatic disease, but much still needs to be done to effectively target this challenging condition. In this review, we discuss about the anatomy of leptomeninges relevant for drug penetration, the conventional and advanced drug delivery methods for LMD. We also discuss the future directions being set by different clinical trials.
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Affiliation(s)
| | - Nupur Biswas
- Rhenix Lifesciences, Hyderabad, Telangana, India
- CureScience, San Diego, California, USA
| | - Jaya Gill
- CureScience, San Diego, California, USA
| | - Santosh Kesari
- Department of Translational Neurosciences, Pacific Neuroscience Institute and Saint John's Cancer Institute at Providence Saint John's Health Center, Santa Monica, California, USA
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Kumar A, Kumar R, Narayan RK, Nath B, Datusalia AK, Rastogi AK, Jha RK, Kumar P, Pareek V, Prasoon P, Faiq MA, Agrawal P, Prasad SN, Kumari C, Asghar A. Anatomical correlates for the newly discovered meningeal layer in the existing literature: A systematic review. Anat Rec (Hoboken) 2024. [PMID: 38924700 DOI: 10.1002/ar.25524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 05/07/2024] [Accepted: 06/04/2024] [Indexed: 06/28/2024]
Abstract
The existence of a previously unrecognized subarachnoid lymphatic-like membrane (SLYM) was reported in a recent study. SLYM is described as an intermediate leptomeningeal layer between the arachnoid and pia mater in mouse and human brains, which divides the subarachnoid space (SAS) into two functional compartments. Being a macroscopic structure, having missed detection in previous studies is surprising. We systematically reviewed the published reports in animals and humans to explore whether prior descriptions of this meningeal layer were reported in some way. A comprehensive search was conducted in PubMed/Medline, EMBASE, Google Scholar, Science Direct, and Web of Science databases using combinations of MeSH terms and keywords with Boolean operators from inception until 31 December 2023. We found at least eight studies that provided structural evidence of an intermediate leptomeningeal layer in the brain or spinal cord. However, unequivocal descriptions for this layer all along the central nervous system were scarce. Obscure names like the epipial, intermediate meningeal, outer pial layers, or intermediate lamella were used to describe it. Its microscopic/ultrastructural details closely resemble the recently reported SLYM. We further examined the counterarguments in current literature that are skeptical of the existence of this layer. The potential physiological and clinical implications of this new meningeal layer are significant, underscoring the urgent need for further exploration of its structural and functional details.
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Affiliation(s)
- Ashutosh Kumar
- Department of Anatomy, All India Institute of Medical Sciences (AIIMS), Patna, India
| | - Rajesh Kumar
- Department of Anatomy, All India Institute of Medical Sciences (AIIMS), Patna, India
| | - Ravi K Narayan
- Department of Anatomy, All India Institute of Medical Sciences (AIIMS), Patna, India
- Department of Anatomy, All India Institute of Medical Sciences (AIIMS), Bhubaneswar, India
| | - Banshi Nath
- Department of Anatomy, All India Institute of Medical Sciences (AIIMS), Patna, India
| | - Ashok K Datusalia
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research-Raebareli, Lucknow, India
| | - Ashok K Rastogi
- Department of Forensic Medicine and Toxicology, All India Institute of Medical Sciences (AIIMS), Patna, India
| | - Rakesh K Jha
- Department of Anatomy, All India Institute of Medical Sciences (AIIMS), Patna, India
- Department of Anatomy, All India Institute of Medical Sciences (AIIMS), Bhubaneswar, India
| | - Pankaj Kumar
- Regional Institute of Ophthalmology, Indira Gandhi Institute of Medical Sciences, Patna, India
| | - Vikas Pareek
- Haskins Laboratories, Yale Child Study Centre, Yale School of Medicine, University of Connecticut, New Haven, Connecticut, USA
| | - Pranav Prasoon
- Department of Anatomy and Cell Biology, George Washington University, Washington, DC, USA
| | - Muneeb A Faiq
- New York University (NYU) Langone Health Center, NYU Robert I Grossman School of Medicine, New York, New York, USA
| | - Prabhat Agrawal
- Spine Surgery Clinic, Department of Orthopedics, All India Institute of Medical Sciences (AIIMS), Patna, India
| | - Surya Nandan Prasad
- Department of Radiodiagnosis, All India Institute of Medical Sciences (AIIMS), Patna, India
| | - Chiman Kumari
- Department of Anatomy, Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Adil Asghar
- Department of Anatomy, All India Institute of Medical Sciences (AIIMS), Patna, India
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Fowler MJ, Riley CO, Tomasson E, Mehta S, Grande-Allen J, Ballester L, Sandberg DI, Janssen CF, Sirianni RW. Engineering subarachnoid trabeculae with electrospun poly(caprolactone) (PCL) scaffolds to study leptomeningeal metastasis in medulloblastoma. BIOMATERIALS ADVANCES 2023; 155:213646. [PMID: 37918168 DOI: 10.1016/j.bioadv.2023.213646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 09/01/2023] [Accepted: 09/29/2023] [Indexed: 11/04/2023]
Abstract
Leptomeningeal metastasis (LM) occurs when cancer cells infiltrate the subarachnoid space (SAS) and metastasize to the fibrous structures that surround the brain and spinal cord. These structures include the leptomeninges (i.e., the pia mater and arachnoid mater), as well as subarachnoid trabeculae, which are collagen-rich fibers that provide mechanical structure for the SAS, support resident cells, and mediate flow of cerebrospinal fluid (CSF). Although there is a strong expectation that the presence of fibers within the SAS influences LM to be a major driver of tumor progression and lethality, exactly how trabecular architecture relates to the process of metastasis in cancer is poorly understood. This lack of understanding is likely due in part to the difficulty of accessing and manipulating this tissue compartment in vivo. Here, we utilized electrospun polycaprolactone (PCL) to produce structures bearing remarkable morphological similarity to native SAS fiber architecture. First, we profiled the native architecture of leptomeningeal and trabecular fibers collected from rhesus macaque monkeys, evaluating both qualitative and quantitative differences in fiber ultrastructure for various regions of the CNS. We then varied electrospinning parameters to produce a small library of PCL scaffolds possessing distinct architectures mimicking the range of fiber properties observed in vivo. For proof of concept, we studied the metastasis-related behaviors of human pediatric medulloblastoma cells cultured in different fiber microenvironments. These studies demonstrated that a more open, porous fiber structure facilitates DAOY cell spread across and infiltration into the meningeal mimic. Our results present a new tissue engineered model of the subarachnoid space and affirm the expectation that fiber architecture plays an important role in mediating metastasis-related behaviors in an in vitro model of pediatric medulloblastoma.
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Affiliation(s)
- Martha J Fowler
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston (UTHealth), Houston, TX, United States of America; Department of Biomedical Engineering, Rice University, Houston, TX, United States of America
| | - Colin O Riley
- Department of Neurological Surgery, UMass Chan Medical School, Worcester, MA, United States of America
| | - Erik Tomasson
- Department of Biomedical Engineering, Rice University, Houston, TX, United States of America
| | - Shail Mehta
- Department of Biomedical Engineering, Rice University, Houston, TX, United States of America
| | - Jane Grande-Allen
- Department of Biomedical Engineering, Rice University, Houston, TX, United States of America
| | - Leomar Ballester
- Department of Pathology, MD Anderson Cancer Center, Houston, TX, United States of America; Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at Houston, United States of America
| | - David I Sandberg
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston (UTHealth), Houston, TX, United States of America; Department of Pediatric Surgery, McGovern Medical School/UTHealth and Children's Memorial Hermann Hospital, United States of America
| | | | - Rachael W Sirianni
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston (UTHealth), Houston, TX, United States of America; Department of Biomedical Engineering, Rice University, Houston, TX, United States of America; Department of Neurological Surgery, UMass Chan Medical School, Worcester, MA, United States of America.
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Santorella E, Balsbaugh JL, Ge S, Saboori P, Baker D, Pachter JS. Proteomic interrogation of the meninges reveals the molecular identities of structural components and regional distinctions along the CNS axis. Fluids Barriers CNS 2023; 20:74. [PMID: 37858244 PMCID: PMC10588166 DOI: 10.1186/s12987-023-00473-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 10/04/2023] [Indexed: 10/21/2023] Open
Abstract
The meninges surround the brain and spinal cord, affording physical protection while also serving as a niche of neuroimmune activity. Though possessing stromal qualities, its complex cellular and extracellular makeup has yet to be elaborated, and it remains unclear whether the meninges vary along the neuroaxis. Hence, studies were carried-out to elucidate the protein composition and structural organization of brain and spinal cord meninges in normal, adult Biozzi ABH mice. First, shotgun, bottom-up proteomics was carried-out. Prominent proteins at both brain and spinal levels included Type II collagen and Type II keratins, representing extracellular matrix (ECM) and cytoskeletal categories, respectively. While the vast majority of total proteins detected was shared between both meningeal locales, more were uniquely detected in brain than in spine. This pattern was also seen when total proteins were subdivided by cellular compartment, except in the case of the ECM category where brain and spinal meninges each had near equal number of unique proteins, and Type V and type III collagen registered exclusively in the spine. Quantitative analysis revealed differential expression of several collagens and cytoskeletal proteins between brain and spinal meninges. High-resolution immunofluorescence and immunogold-scanning electronmicroscopy on sections from whole brain and spinal cord - still encased within bone -identified major proteins detected by proteomics, and highlighted their association with cellular and extracellular elements of variously shaped arachnoid trabeculae. Western blotting aligned with the proteomic and immunohistological analyses, reinforcing differential appearance of proteins in brain vs spinal meninges. Results could reflect regional distinctions in meninges that govern protective and/or neuroimmune functions.
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Affiliation(s)
- Elise Santorella
- Department of Immunology, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA
| | - Jeremy L Balsbaugh
- Proteomics and Metabolomics Facility, Center for Open Research Resources & Equipment, University of Connecticut, Storrs, CT, 06269, USA
| | - Shujun Ge
- Department of Immunology, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA
| | - Parisa Saboori
- Department of Mechanical Engineering, Manhattan College, Bronx, NY, 10071, USA
| | - David Baker
- Blizard Institute, Queen Mary University of London, London, England
| | - Joel S Pachter
- Department of Immunology, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA.
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Rossinelli D, Killer HE, Meyer P, Knott G, Fourestey G, Kurtcuoglu V, Kohler C, Gruber P, Remonda L, Neutzner A, Berberat J. Large-scale morphometry of the subarachnoid space of the optic nerve. Fluids Barriers CNS 2023; 20:21. [PMID: 36944985 PMCID: PMC10029327 DOI: 10.1186/s12987-023-00423-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 03/10/2023] [Indexed: 03/23/2023] Open
Abstract
BACKGROUND The meninges, formed by dura, arachnoid and pia mater, cover the central nervous system and provide important barrier functions. Located between arachnoid and pia mater, the cerebrospinal fluid (CSF)-filled subarachnoid space (SAS) features a variety of trabeculae, septae and pillars. Like the arachnoid and the pia mater, these structures are covered with leptomeningeal or meningothelial cells (MECs) that form a barrier between CSF and the parenchyma of the optic nerve (ON). MECs contribute to the CSF proteome through extensive protein secretion. In vitro, they were shown to phagocytose potentially toxic proteins, such as α-synuclein and amyloid beta, as well as apoptotic cell bodies. They therefore may contribute to CSF homeostasis in the SAS as a functional exchange surface. Determining the total area of the SAS covered by these cells that are in direct contact with CSF is thus important for estimating their potential contribution to CSF homeostasis. METHODS Using synchrotron radiation-based micro-computed tomography (SRµCT), two 0.75 mm-thick sections of a human optic nerve were acquired at a resolution of 0.325 µm/pixel, producing images of multiple terabytes capturing the geometrical details of the CSF space. Special-purpose supercomputing techniques were employed to obtain a pixel-accurate morphometric description of the trabeculae and estimate internal volume and surface area of the ON SAS. RESULTS In the bulbar segment, the ON SAS microstructure is shown to amplify the MECs surface area up to 4.85-fold compared to an "empty" ON SAS, while just occupying 35% of the volume. In the intraorbital segment, the microstructure occupies 35% of the volume and amplifies the ON SAS area 3.24-fold. CONCLUSIONS We provided for the first time an estimation of the interface area between CSF and MECs. This area is of importance for estimating a potential contribution of MECs on CSF homeostasis.
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Affiliation(s)
- Diego Rossinelli
- Institute of Neuroradiology, Kantonsspital Aarau, Tellstrasse 25, CH-5001, Aarau, Switzerland.
- Institute of Physiology, University of Zurich, Zurich, Switzerland.
| | | | - Peter Meyer
- Ocular Pharmacology and Physiology, University Hospital of Basel, Basel, Switzerland
| | - Graham Knott
- Biological Electron Microscopy Facility (BioEM), Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
| | - Gilles Fourestey
- Scientific IT & Application Support (SCITAS), Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
| | | | - Corina Kohler
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Philipp Gruber
- Institute of Neuroradiology, Kantonsspital Aarau, Tellstrasse 25, CH-5001, Aarau, Switzerland
| | - Luca Remonda
- Institute of Neuroradiology, Kantonsspital Aarau, Tellstrasse 25, CH-5001, Aarau, Switzerland
- Medical Faculty, University of Bern, Bern, Switzerland
| | - Albert Neutzner
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Jatta Berberat
- Institute of Neuroradiology, Kantonsspital Aarau, Tellstrasse 25, CH-5001, Aarau, Switzerland
- Geriatric Psychiatry, Department of Psychiatry, University Hospitals of Geneva, University of Geneva, Geneva, Switzerland
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Muñoz Sarmiento DM, Rodríguez Montaño ÓL, Alarcón Castiblancoa JD, Cortés Rodríguez CJ. The impact of horizontal eye movements versus intraocular pressure on optic nerve head biomechanics: A tridimensional finite element analysis study. Heliyon 2023; 9:e13634. [PMID: 36865452 PMCID: PMC9970910 DOI: 10.1016/j.heliyon.2023.e13634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 01/31/2023] [Accepted: 02/06/2023] [Indexed: 02/13/2023] Open
Abstract
It has been proposed that eye movements could be related to glaucoma development. This research aimed to compare the impact of intraocular pressure (IOP) versus horizontal duction on optic nerve head (ONH) strains. Thus, a tridimensional finite element model of the eye including the three tunics of the eye, all of the meninges, and the subarachnoid space (SAS) was developed using a series of medical tests and anatomical data. The ONH was divided into 22 subregions, and the model was subjected to 21 different eye pressures, as well as 24 different degrees of adduction and abduction ranging from 0.5° to 12°. Mean deformations were documented along anatomical axes and in principal directions. Additionally, the impact of tissue stiffness was assessed. The results show no statistically significant differences between the lamina cribrosa (LC) strains due to eye rotation and IOP variation. However, when assessing LC regions some experienced a reduction in principal strains following a 12° duction, while after the IOP reached 12 mmHg, all LC subzones showed an increase in strains. From an anatomical perspective, the effect on the ONH following 12° duction was opposite to that observed after a rise in IOP. Moreover, high strain dispersion inside the ONH subregions was obtained with lateral eye movements, which was not observed with increased IOP and variation. Finally, SAS and orbital fat stiffness strongly influenced ONH strains during eye movements, while SAS stiffness was also influential under ocular hypertension. Even if horizontal eye movements cause large ONH deformations, their biomechanical effect would be markedly distinct from that induced by IOP. It could be predicted that, at least in physiological conditions, their potential to cause axonal injury would not be so relevant. Thus, a causative role in glaucoma does not appear likely. By contrast, an important role of SAS would be expectable.
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Affiliation(s)
- Diana Marcela Muñoz Sarmiento
- Grupo de Investigación en Biomecánica, Universidad Nacional de Colombia, Colombia,Sociedad de Oftalmología Eduardo Arenas Archila, Colombia,Laboratorio de Anatomía y Fisiología, Grupo de Ciencias Básicas y Laboratorios, Universidad Manuela Beltrán, Colombia,Corresponding author. Grupo de Investigación en Biomecánica, Universidad Nacional de Colombia, Colombia.
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Kraus V, Krampe-Heni F, Steinborn M. Long-term monitoring of children with Pseudo Tumor Cerebri Syndrome by transbulbar sonography. Eur J Paediatr Neurol 2023; 44:9-17. [PMID: 36738658 DOI: 10.1016/j.ejpn.2023.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 01/12/2023] [Accepted: 01/17/2023] [Indexed: 01/20/2023]
Abstract
Determination of optic nerve sheath diameter (ONSD) with transbulbar sonography has become an easily accessible and time-effective tool in the assessment of increased intracranial pressure. The aim of our study was to evaluate the usefulness of transbulbar sonography in the initial diagnosis and in follow-up examinations of children and adolescents with the diagnosis of pseudotumor cerebri syndrome (PTCS). We retrospectively reviewed imaging results of 24 patients aged 0.75-17 years with PTCS. Serial transbulbar sonography examinations were performed between 2011 and 2021. Sonographic evaluation included the ONSD, papilledema and subarachnoid space. 240 sonographic measurements taken at 108 time points in 17 patients met the inclusion criteria. All patients underwent serial lumbar punctures and routine fundoscopy in close relation to transbulbar sonography. We found that ONSD values remained high in all patients. The longest follow-up period was dated 2498 days (6.84 years) after initial diagnosis. Papilledema resolved in close correlation to fundoscopy normalization. In 16/17 patients the subarachnoid space remained cystic in appearance. These findings were independent of clinical symptoms and lumbar puncture opening pressure. We conclude that transbulbar sonography is a useful diagnostic tool in the initial diagnostic workup of children with PTCS. On follow-up however ONSD values and the cystic transformation of the subarachnoid space remained pathologic in the majority of cases while papilledema resolved parallel to fundoscopy findings. Serial measurements of ONSD are therefore of limited value in the follow-up of patients with PTCS and cannot be considered a reliable tool in subsequent therapeutic decisions.
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Affiliation(s)
- V Kraus
- Technical University Munich, Department of Pediatrics, Pediatric Neurology, Kölner Platz 1, 80804, Munich, Germany; Technical University Munich, Department of Pediatrics, Chair of Social Pediatrics, Heiglhofstraße 65, 81377, Munich, Germany; Community Hospital Munich, Department of Pediatrics, Kölner Platz 1, 80804 Munich, Germany.
| | - F Krampe-Heni
- Technical University Munich, Department of Pediatrics, Pediatric Neurology, Kölner Platz 1, 80804, Munich, Germany; Community Hospital Munich, Department of Pediatrics, Kölner Platz 1, 80804 Munich, Germany
| | - M Steinborn
- Community Hospital Munich, Department of Diagnostic and Interventional Radiology and Pediatric Radiology, Kölner Platz 1, 80804, Munich, 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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McNamara EH, Knutsen A, Korotcov A, Bosomtwi A, Liu J, Fu AH, Kostelnik C, Grillakis A, Spencer H, Dardzinski BJ, McCabe JT. Meningeal and visual pathway MRI analysis after single and repetitive Closed-Head Impact Model of Engineered Rotational Acceleration (CHIMERA)-induced disruption in male and female mice. J Neurotrauma 2022; 39:784-799. [PMID: 35243900 PMCID: PMC9225425 DOI: 10.1089/neu.2021.0494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The consequences of forceful rotational acceleration on the central nervous system are not fully understood. While traumatic brain injury (TBI) research primarily has focused on effects related to the brain parenchyma, reports of traumatic meningeal enhancement in TBI patients may possess clinical significance. The objective of this study was to evaluate the meninges and brain for changes in dynamic contrast enhancement (DCE) magnetic resonance imaging (MRI) following closed-head impact model of engineered rotational acceleration (CHIMERA)–induced cerebral insult. Adult male and female mice received one (1 × ; n = 19 CHIMERA, n = 19 Sham) or four (4 × one/day; n = 18 CHIMERA, n = 12 Sham) injuries. Each animal underwent three MRI scans: 1 week before injury, immediately after the final injury, and 1 week post-injury. Compared with baseline readings and measures in sham animals, meningeal DCE in males was increased after single impact and repetitive injury. In female mice, DCE was elevated relative to their baseline level after a single impact. One week after CHIMERA, the meningeal enhancement returned to below baseline for single injured male mice, but compared with uninjured mice remained elevated in both sexes in the multiple impact groups. Pre-DCE meningeal T2-weighted relaxation time was increased only after 1 × CHIMERA in injured mice. Since vision is impaired after CHIMERA, visual pathway regions were analyzed through imaging and glial fibrillary acidic protein (GFAP) histology. Initial DCE in the lateral geniculate nucleus (LGN) and superior colliculus (SC) and T2 increases in the optic tract (OPT) and LGN were observed after injury with decreases in DCE and T2 1 week later. Astrogliosis was apparent in the OPT and SC with increased GFAP staining 7 days post-injury. To our knowledge, this is the first study to examine meningeal integrity after CHIMERA in both male and female rodents. DCE-MRI may serve as a useful approach for pre-clinical models of meningeal injury that will enable further evaluation of the underlying mechanisms.
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Affiliation(s)
- Eileen H McNamara
- Uniformed Services University of the Health Sciences, Anatomy, Physiology & Genetics, Bethesda, Maryland, United States;
| | - Andrew Knutsen
- Henry M Jackson Foundation for the Advancement of Military Medicine Inc, 44069, Center for Neuroscience and Regenerative Medicine, Bethesda, Maryland, United States;
| | - Alexandru Korotcov
- Henry M. Jackson Foundation, Center for Neuroscience and Regenerative Medicine, Bethesda, Maryland, United States.,Uniformed Services University, Radiology & Radiological Sciences, Bethesda, Maryland, United States;
| | - Asamoah Bosomtwi
- Henry M Jackson Foundation for the Advancement of Military Medicine Inc, 44069, CNRM, 4301 Jones Bridge Road, Bethesda, Bethesda, Maryland, United States, 20814.,Uniformed Services University of the Health Sciences, 1685, Radiology & Radiological Science, 4301 Jones Bridge Road, Bethesda, Maryland, United States, 20814-4712;
| | - Jiong Liu
- Uniformed Services University of the Health Sciences, Anatomy, Physiology & Genetics, 4301 Jones Bridge Road, Bethesda, Maryland, United States, 20814-4799;
| | - Amanda H Fu
- Uniformed Services University of the Health Sciences, Anatomy, Physiology & Genetics, Bethesda, Maryland, United States;
| | - Claire Kostelnik
- Uniformed Services University of the Health Sciences, Anatomy, Physiology & Genetics, Bethesda, Maryland, United States;
| | - Antigone Grillakis
- Uniformed Services University, Anatomy, Physiology & Genetics, Bethesda, United States;
| | - Haley Spencer
- Uniformed Services University of the Health Sciences, Psychiatry, Bethesda, Maryland, United States;
| | - Bernard J Dardzinski
- Uniformed Services University of the Health Sciences, 1685, Radiology and Radiological Sciences, Bethesda, Maryland, United States;
| | - Joseph T McCabe
- Uniformed Services University of the Health Sciences, Anatomy, Physiology & Genetics, Bethesda, Maryland, United States;
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Anagnostakou V, Epshtein M, Ughi GJ, King RM, Valavanis A, Puri AS, Gounis MJ. Transvascular in vivo microscopy of the subarachnoid space. J Neurointerv Surg 2022; 14:neurintsurg-2021-018544. [PMID: 35115394 DOI: 10.1136/neurintsurg-2021-018544] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 01/19/2022] [Indexed: 01/22/2023]
Abstract
BACKGROUND The micro-architectonics of the subarachnoid space (SAS) remain partially understood and largely ignored, likely the result of the inability to image these structures in vivo. We explored transvascular imaging with high-frequency optical coherence tomography (HF-OCT) to interrogate the SAS. METHODS In vivo HF-OCT was performed in 10 dogs in both the posterior and anterior cerebral circulations. The conduit vessels used were the basilar, anterior spinal, and middle and anterior cerebral arteries through which the perivascular SAS was imaged. The HF-OCT imaging probe was introduced via a microcatheter and images were acquired using a contrast injection (3.5 mL/s) for blood clearance. Segmentation and three-dimensional rendering of HF-OCT images were performed to study the different configurations and porosity of the subarachnoid trabeculae (SAT) as a function of location. RESULTS Of 13 acquisitions, three were excluded due to suboptimal image quality. Analysis of 15 locations from seven animals was performed showing six distinct configurations of arachnoid structures in the posterior circulation and middle cerebral artery, ranging from minimal presence of SAT to dense networks and membranes. Different locations showed predilection for specific arachnoid morphologies. At the basilar bifurcation, a thick, fenestrated membrane had a unique morphology. SAT average thickness was 100 µm and did not vary significantly based on location. Similarly, the porosity of the SAT averaged 91% and showed low variability. CONCLUSION We have demonstrated the feasibility to image the structures of the SAS with transvascular HF-OCT. Future studies are planned to further map the SAT to increase our understanding of their function and possible impact on neurovascular pathologies.
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Affiliation(s)
- Vania Anagnostakou
- New England Center for Stroke Research, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Mark Epshtein
- New England Center for Stroke Research, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Giovanni J Ughi
- New England Center for Stroke Research, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.,Research and Development, Gentuity LLC, Sudbury, MA, USA
| | - Robert M King
- New England Center for Stroke Research, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Antonios Valavanis
- Clinical Neuroscience Center, University Hospital Zurich Department of Neuroradiology, Zurich, ZH, Switzerland
| | - Ajit S Puri
- New England Center for Stroke Research, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Matthew J Gounis
- New England Center for Stroke Research, Department of Radiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
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Lu S, Brusic A, Gaillard F. Arachnoid Membranes: Crawling Back into Radiologic Consciousness. AJNR Am J Neuroradiol 2022; 43:167-175. [PMID: 34711549 PMCID: PMC8985673 DOI: 10.3174/ajnr.a7309] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Accepted: 07/29/2021] [Indexed: 02/03/2023]
Abstract
The arachnoid membranes are projections of connective tissue in the subarachnoid space that connect the arachnoid mater to the pia mater. These are underappreciated and largely unrecognized by most neuroradiologists despite being found to be increasingly important in the pathogenesis, imaging, and treatment of communicating hydrocephalus. This review aims to provide neuroradiologists with an overview of the history, embryology, histology, anatomy, and normal imaging appearance of these membranes, as well as some examples of their clinical importance.
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Affiliation(s)
- S. Lu
- From the Department of Radiology (S.L., A.B., F.G.), Royal Melbourne Hospital, Parkville, Victoria, Australia
| | - A. Brusic
- From the Department of Radiology (S.L., A.B., F.G.), Royal Melbourne Hospital, Parkville, Victoria, Australia
| | - F. Gaillard
- From the Department of Radiology (S.L., A.B., F.G.), Royal Melbourne Hospital, Parkville, Victoria, Australia,Faculty of Medicine, Dentistry, and Health Sciences (F.G.), University of Melbourne, Parkville, Victoria, Australia
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