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Leblond L, Sudres P, Evin M. Cerebro-spinal flow pattern in the cervical subarachnoid space of healthy volunteers: Influence of the spinal cord morphology. PLoS One 2024; 19:e0290927. [PMID: 39186510 PMCID: PMC11346662 DOI: 10.1371/journal.pone.0290927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 04/22/2024] [Indexed: 08/28/2024] Open
Abstract
INTRODUCTION Toward further cerebro-spinal flow quantification in clinical practice, this study aims at assessing the variations in the cerebro spinal fluid flow pattern associated with change in the morphology of the subarachnoid space of the cervical canal of healthy humans by developing a computational fluid dynamics model. METHODS 3D T2-space MRI sequence images of the cervical spine were used to segment 11 cervical subarachnoid space. Model validation (time-step, mesh size, size and number of boundary layers, influences of parted inflow and inflow continuous velocity) was performed a 40-year-old patient-specific model. Simulations were performed using computational fluid dynamics approach simulating transient flow (Sparlart-Almaras turbulence model) with a mesh size of 0.6, 6 boundary layers of 0.05 mm, a time step of 20 ms simulated on 15 cycles. Distributions of components velocity and WSS were respectively analyzed within the subarachnoid space (intervertebral et intravertebral levels) and on dura and pia maters. RESULTS Mean values cerebro spinal fluid velocity in specific local slices of the canal range between 0.07 and 0.17 m.s-1 and 0.1 and 0.3 m.s-1 for maximum values. Maximum wall shear stress values vary between 0.1 and 0.5 Pa with higher value at the middle of the cervical spine on pia mater and at the lower part of the cervical spine on dura mater. Intra and inter-individual variations of the wall shear stress were highlighted significant correlation gwith compression ratio (r = 0.76), occupation ratio and cross section area of the spinal cord. CONCLUSION The inter-individual variability in term of subarachnoid canal morphology and spinal cord position influence the cerebro-spinal flow pattern, highlighting the significance of canal morphology investigation before surgery.
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Affiliation(s)
- Lugdivine Leblond
- Laboratoire de Biomécanique Appliquée, UMRT24, Aix Marseille Université, Marseille, France
- iLab-Spine - Laboratoire International en Imagerie et Biomécanique du Rachis, Marseille, France
| | - Patrice Sudres
- Laboratoire de Biomécanique Appliquée, UMRT24, Aix Marseille Université, Marseille, France
- iLab-Spine - Laboratoire International en Imagerie et Biomécanique du Rachis, Marseille, France
| | - Morgane Evin
- Laboratoire de Biomécanique Appliquée, UMRT24, Aix Marseille Université, Marseille, France
- iLab-Spine - Laboratoire International en Imagerie et Biomécanique du Rachis, Marseille, France
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2
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Shlobin NA, Staple BL, Sclafani M, Harter DH. The Glymphatic System and Subarachnoid Lymphatic-Like Membrane: Recent Developments in Cerebrospinal Fluid Research. World Neurosurg 2024; 190:147-156. [PMID: 39002777 DOI: 10.1016/j.wneu.2024.07.062] [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: 03/08/2024] [Revised: 07/05/2024] [Accepted: 07/06/2024] [Indexed: 07/15/2024]
Abstract
BACKGROUND Cerebrospinal fluid (CSF) circulates throughout the ventricles, cranial and spinal subarachnoid spaces, and central spinal cord canal. CSF protects the central nervous system through mechanical cushioning, regulation of intracranial pressure, regulation of metabolic homeostasis, and provision of nutrients. Recently, investigators have characterized the glial-lymphatic (glymphatic) system, the analog of the lymphatic system in the central nervous system, and described a fourth meningeal layer; the subarachnoid lymphatic-like membrane (SLYM)relevant to the CSF. METHODS A narrative review was conducted. RESULTS In this review, we summarize these advances. We describe the development of the original model, controversies, a revised model, and a new conceptual framework. We characterize the biological functions, influence of sleep-wake cycles, and effect of aging with relevance to the glymphatic system. We highlight the role of the glymphatic system in Alzheimer's disease, idiopathic normal pressure hydrocephalus, ischemic stroke, subarachnoid hemorrhage, and traumatic brain injury. Next, we characterize the structure and role of the SLYM. Finally, we explore the relevance of the glymphatic system and SLYM to neurosurgery. CONCLUSIONS This manuscript will inform clinicians and scientists regarding preclinical and translational advances in the understanding of the structure, dynamics, and function of the CSF.
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Affiliation(s)
- Nathan A Shlobin
- Department of Neurological Surgery, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.
| | - Brandon L Staple
- College of Medicine, University of Nebraska, Omaha, Nebraska, USA
| | | | - David H Harter
- Department of Neurosurgery, NYU Langone, New York, New York, USA
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3
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Barz S, Friedemann M, Voigt S, Melloh M, Barz T. Epidural pressure measurement using a fiber-optic sensor (proof-of-principle in vivo animal trial). Animal Model Exp Med 2024. [PMID: 38981680 DOI: 10.1002/ame2.12469] [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: 03/02/2024] [Accepted: 06/14/2024] [Indexed: 07/11/2024] Open
Abstract
BACKGROUND An increase in epidural pressure around the stenosis has been observed in patients with lumbar spinal stenosis (LSS) with positive signs of sedimentation or redundant nerve roots. Further analysis of the pressure conditions in the stenotic area would be of great interest. We hypothesized that it would be possible to determine the physiological parameters of the epidural pulse wave and its course in pathological stenosis as a basis for objective identification of LSS based on pressure using a new measuring method with continuous spatial and temporal resolution. METHODS We performed a single-case proof-of-principle in vivo animal trial and used a newly developed hybrid pressure-measurement probe with a fiber-tip Fabry-Pérot interferometer and several fiber Bragg gratings (FBG). RESULTS With reproducible precision, we determined the mean epidural pressure to be 7.5 mmHg and the peak-to-peak value to be 4-5 mmHg. When analyzing the pressure measured by an FBG array, both the heart and respiratory rates can be precisely determined. This study was the first to measure the pulse wave velocity of the cerebrospinal fluid pressure wave as 0.97 m/s using the newly developed pressure probe. A simulated LSS was detected in real time and located exactly. CONCLUSIONS The developed fiber-optic pressure sensor probe enables a new objective measurement of epidural pressure. We confirmed our hypothesis that physiological parameters of the epidural pulse wave can be determined and that it is possible to identify an LSS.
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Affiliation(s)
- Susanne Barz
- Department of Anaesthesiology, Intensive Care Medicine and Pain Therapy, Rostock University Medical Center, Universitätsmedizin Rostock, Rostock, Germany
| | | | | | - Markus Melloh
- School of Public Health and Social Work, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Thomas Barz
- Orthopedic Department, University of Greifswald, Greifswald, Germany
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Woodward OB, Driver I, Schwarz ST, Hart E, Wise R. Assessment of brainstem function and haemodynamics by MRI: challenges and clinical prospects. Br J Radiol 2023; 96:20220940. [PMID: 37721043 PMCID: PMC10607409 DOI: 10.1259/bjr.20220940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 04/25/2023] [Accepted: 05/24/2023] [Indexed: 09/19/2023] Open
Abstract
MRI offers techniques for non-invasively measuring a range of aspects of brain tissue function. Blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) is widely used to assess neural activity, based on the brain's haemodynamic response, while arterial spin labelling (ASL) MRI is a non-invasive method of quantitatively mapping cerebral perfusion. Both techniques can be applied to measure cerebrovascular reactivity (CVR), an important marker of the health of the cerebrovascular system. BOLD, ASL and CVR have been applied to study a variety of disease processes and are already used in certain clinical circumstances. The brainstem is a critical component of the central nervous system and is implicated in a variety of disease processes. However, its function is difficult to study using MRI because of its small size and susceptibility to physiological noise. In this article, we review the physical and biological underpinnings of BOLD and ASL and their application to measure CVR, discuss the challenges associated with applying them to the brainstem and the opportunities for brainstem MRI in the research and clinical settings. With further optimisation, functional MRI techniques could feasibly be used to assess brainstem haemodynamics and neural activity in the clinical setting.
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Affiliation(s)
- Owen Bleddyn Woodward
- Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, United Kingdom
| | - Ian Driver
- Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, United Kingdom
| | | | - Emma Hart
- University of Bristol, Bristol, United Kingdom
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5
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Linninger AA, Barua D, Hang Y, Iadevaia S, Vakilynejad M. A mechanistic pharmacokinetic model for intrathecal administration of antisense oligonucleotides. Front Physiol 2023; 14:1130925. [PMID: 37334053 PMCID: PMC10272745 DOI: 10.3389/fphys.2023.1130925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 05/15/2023] [Indexed: 06/20/2023] Open
Abstract
Intrathecal administration is an important mode for delivering biological agents targeting central nervous system (CNS) diseases. However, current clinical practices lack a sound theorical basis for a quantitative understanding of the variables and conditions that govern the delivery efficiency and specific tissue targeting especially in the brain. This work presents a distributed mechanistic pharmacokinetic model (DMPK) for predictive analysis of intrathecal drug delivery to CNS. The proposed DMPK model captures the spatiotemporal dispersion of antisense oligonucleotides (ASO) along the neuraxis over clinically relevant time scales of days and weeks as a function of infusion, physiological and molecular properties. We demonstrate its prediction capability using biodistribution data of antisense oligonucleotide (ASO) administration in non-human primates. The results are in close agreement with the observed ASO pharmacokinetics in all key compartments of the central nervous system. The model enables determination of optimal injection parameters such as intrathecal infusion volume and duration for maximum ASO delivery to the brain. Our quantitative model-guided analysis is suitable for identifying optimal parameter settings to target specific brain regions with therapeutic drugs such as ASOs.
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Affiliation(s)
| | - Dipak Barua
- Takeda Pharmaceuticals, Cambridge, MA, United States
| | - Yaming Hang
- Takeda Pharmaceuticals, Cambridge, MA, United States
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Elabasy A, Suhonen M, Rajna Z, Hosni Y, Kananen J, Annunen J, Ansakorpi H, Korhonen V, Seppänen T, Kiviniemi V. Respiratory brain impulse propagation in focal epilepsy. Sci Rep 2023; 13:5222. [PMID: 36997658 PMCID: PMC10063583 DOI: 10.1038/s41598-023-32271-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 03/24/2023] [Indexed: 04/03/2023] Open
Abstract
Respiratory brain pulsations pertaining to intra-axial hydrodynamic solute transport are markedly altered in focal epilepsy. We used optical flow analysis of ultra-fast functional magnetic resonance imaging (fMRI) data to investigate the velocity characteristics of respiratory brain impulse propagation in patients with focal epilepsy treated with antiseizure medication (ASM) (medicated patients with focal epilepsy; ME, n = 23), drug-naïve patients with at least one seizure (DN, n = 19) and matched healthy control subjects (HC, n = 75). We detected in the two patient groups (ME and DN) several significant alterations in the respiratory brain pulsation propagation velocity, which showed a bidirectional change dominated by a reduction in speed. Furthermore, the respiratory impulses moved more in reversed or incoherent directions in both patient groups vs. the HC group. The speed reductions and directionality changes occurred in specific phases of the respiratory cycle. In conclusion, irrespective of medication status, both patient groups showed incoherent and slower respiratory brain impulses, which may contribute to epileptic brain pathology by hindering brain hydrodynamics.
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Affiliation(s)
- Ahmed Elabasy
- Center for Machine Vision and Signal Analysis, University of Oulu, 90014, Oulu, Finland.
- Oulu Functional NeuroImaging, Diagnostic Radiology, Medical Research Center/HTS, Oulu University Hospital, 90029, Oulu, Finland.
| | - Mia Suhonen
- Medical Imaging, Physics and Technology, University of Oulu, 90029, Oulu, Finland.
- Oulu Functional NeuroImaging, Diagnostic Radiology, Medical Research Center/HTS, Oulu University Hospital, 90029, Oulu, Finland.
| | - Zalan Rajna
- Center for Machine Vision and Signal Analysis, University of Oulu, 90014, Oulu, Finland
| | - Youssef Hosni
- Center for Machine Vision and Signal Analysis, University of Oulu, 90014, Oulu, Finland
- Oulu Functional NeuroImaging, Diagnostic Radiology, Medical Research Center/HTS, Oulu University Hospital, 90029, Oulu, Finland
| | - Janne Kananen
- Medical Imaging, Physics and Technology, University of Oulu, 90029, Oulu, Finland
- Oulu Functional NeuroImaging, Diagnostic Radiology, Medical Research Center/HTS, Oulu University Hospital, 90029, Oulu, Finland
- Clinical Neurophysiology, Oulu University Hospital, 90029 OYS, Oulu, Finland
| | - Johanna Annunen
- Research Unit of Clinical Neuroscience, Neurology, University of Oulu, 90029, Oulu, Finland
- Neurocenter, Neurology, Oulu University Hospital, Member of ERN EpiCARE, 90029, Oulu, Finland
- MRC, Oulu University Hospital, 90029, Oulu, Finland
| | - Hanna Ansakorpi
- Research Unit of Clinical Neuroscience, Neurology, University of Oulu, 90029, Oulu, Finland
| | - Vesa Korhonen
- Medical Imaging, Physics and Technology, University of Oulu, 90029, Oulu, Finland
- Oulu Functional NeuroImaging, Diagnostic Radiology, Medical Research Center/HTS, Oulu University Hospital, 90029, Oulu, Finland
| | - Tapio Seppänen
- Center for Machine Vision and Signal Analysis, University of Oulu, 90014, Oulu, Finland
| | - Vesa Kiviniemi
- Medical Imaging, Physics and Technology, University of Oulu, 90029, Oulu, Finland.
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7
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Cavelier S, Quarrington RD, Jones CF. Tensile properties of human spinal dura mater and pericranium. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2022; 34:4. [PMID: 36586044 PMCID: PMC9805418 DOI: 10.1007/s10856-022-06704-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Accepted: 11/15/2022] [Indexed: 06/17/2023]
Abstract
Autologous pericranium is a promising dural graft material. An optimal graft should exhibit similar mechanical properties to the native dura, but the mechanical properties of human pericranium have not been characterized, and studies of the biomechanical performance of human spinal dura are limited. The primary aim of this study was to measure the tensile structural and material properties of the pericranium, in the longitudinal and circumferential directions, and of the dura in each spinal region (cervical, thoracic and lumbar) and in three directions (longitudinal anterior and posterior, and circumferential). The secondary aim was to determine corresponding constitutive stress-strain equations using a one-term Ogden model. A total of 146 specimens were tested from 7 cadavers. Linear regression models assessed the effect of tissue type, region, and orientation on the structural and material properties. Pericranium was isotropic, while spinal dura was anisotropic with higher stiffness and strength in the longitudinal than the circumferential direction. Pericranium had lower strength and modulus than spinal dura across all regions in the longitudinal direction but was stronger and stiffer than dura in the circumferential direction. Spinal dura and pericranium had similar strain at peak force, toe, and yield, across all regions and directions. Human pericranium exhibits isotropic mechanical behavior that lies between that of the longitudinal and circumferential spinal dura. Further studies are required to determine if pericranium grafts behave like native dura under in vivo loading conditions. The Ogden parameters reported may be used for computational modeling of the central nervous system. Graphical abstract.
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Affiliation(s)
- Sacha Cavelier
- Adelaide Spinal Research Group, Centre for Orthopaedic & Trauma Research, Adelaide Medical School, The University of Adelaide, Adelaide, SA, 5005, Australia
- Department of Mechanical Engineering, McGill University, Montréal, QC, H3A 0C3, Canada
| | - Ryan D Quarrington
- Adelaide Spinal Research Group, Centre for Orthopaedic & Trauma Research, Adelaide Medical School, The University of Adelaide, Adelaide, SA, 5005, Australia
- School of Mechanical Engineering, The University of Adelaide, Adelaide, SA, 5005, Australia
| | - Claire F Jones
- Adelaide Spinal Research Group, Centre for Orthopaedic & Trauma Research, Adelaide Medical School, The University of Adelaide, Adelaide, SA, 5005, Australia.
- School of Mechanical Engineering, The University of Adelaide, Adelaide, SA, 5005, Australia.
- Department of Orthopaedics and Trauma, Royal Adelaide Hospital, Adelaide, SA, 5000, Australia.
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8
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Gholampour S, Frim D, Yamini B. Long-term recovery behavior of brain tissue in hydrocephalus patients after shunting. Commun Biol 2022; 5:1198. [PMID: 36344582 PMCID: PMC9640582 DOI: 10.1038/s42003-022-04128-8] [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: 07/13/2022] [Accepted: 10/18/2022] [Indexed: 11/11/2022] Open
Abstract
The unpredictable complexities in hydrocephalus shunt outcomes may be related to the recovery behavior of brain tissue after shunting. The simulated cerebrospinal fluid (CSF) velocity and intracranial pressure (ICP) over 15 months after shunting were validated by experimental data. The mean strain and creep of the brain had notable changes after shunting and their trends were monotonic. The highest stiffness of the hydrocephalic brain was in the first consolidation phase (between pre-shunting to 1 month after shunting). The viscous component overcame and damped the input load in the third consolidation phase (after the fifteenth month) and changes in brain volume were stopped. The long-intracranial elastance (long-IE) changed oscillatory after shunting and there was not a linear relationship between long-IE and ICP. We showed the long-term effect of the viscous component on brain recovery behavior of hydrocephalic brain. The results shed light on the brain recovery mechanism after shunting and the mechanisms for shunt failure.
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Affiliation(s)
| | - David Frim
- Department of Neurological Surgery, University of Chicago, Chicago, IL, USA
| | - Bakhtiar Yamini
- Department of Neurological Surgery, University of Chicago, Chicago, IL, USA.
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9
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Gholampour S, Yamini B, Droessler J, Frim D. A New Definition for Intracranial Compliance to Evaluate Adult Hydrocephalus After Shunting. Front Bioeng Biotechnol 2022; 10:900644. [PMID: 35979170 PMCID: PMC9377221 DOI: 10.3389/fbioe.2022.900644] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 06/13/2022] [Indexed: 12/26/2022] Open
Abstract
The clinical application of intracranial compliance (ICC), ∆V/∆P, as one of the most critical indexes for hydrocephalus evaluation was demonstrated previously. We suggest a new definition for the concept of ICC (long-term ICC) where there is a longer amount of elapsed time (up to 18 months after shunting) between the measurement of two values (V1 and V2 or P1 and P2). The head images of 15 adult patients with communicating hydrocephalus were provided with nine sets of imaging in nine stages: prior to shunting, and 1, 2, 3, 6, 9, 12, 15, and 18 months after shunting. In addition to measuring CSF volume (CSFV) in each stage, intracranial pressure (ICP) was also calculated using fluid–structure interaction simulation for the noninvasive calculation of ICC. Despite small increases in the brain volume (16.9%), there were considerable decreases in the ICP (70.4%) and CSFV (80.0%) of hydrocephalus patients after 18 months of shunting. The changes in CSFV, brain volume, and ICP values reached a stable condition 12, 15, and 6 months after shunting, respectively. The results showed that the brain tissue needs approximately two months to adapt itself to the fast and significant ICP reduction due to shunting. This may be related to the effect of the “viscous” component of brain tissue. The ICC trend between pre-shunting and the first month of shunting was descending for all patients with a “mean value” of 14.75 ± 0.6 ml/cm H2O. ICC changes in the other stages were oscillatory (nonuniform). Our noninvasive long-term ICC calculations showed a nonmonotonic trend in the CSFV–ICP graph, the lack of a linear relationship between ICC and ICP, and an oscillatory increase in ICC values during shunt treatment. The oscillatory changes in long-term ICC may reflect the clinical variations in hydrocephalus patients after shunting.
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10
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Patient-specific computational fluid dynamic simulation of cerebrospinal fluid flow in the intracranial space. Brain Res 2022; 1790:147962. [DOI: 10.1016/j.brainres.2022.147962] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 05/16/2022] [Accepted: 05/31/2022] [Indexed: 11/24/2022]
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11
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Fabrication and Modelling of a Reservoir-Based Drug Delivery System for Customizable Release. Pharmaceutics 2022; 14:pharmaceutics14040777. [PMID: 35456611 PMCID: PMC9025308 DOI: 10.3390/pharmaceutics14040777] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 03/29/2022] [Accepted: 03/29/2022] [Indexed: 01/27/2023] Open
Abstract
Localized therapy approaches have emerged as an alternative drug administration route to overcome the limitations of systemic therapies, such as the crossing of the blood–brain barrier in the case of brain tumor treatment. For this, implantable drug delivery systems (DDS) have been developed and extensively researched. However, to achieve an effective localized treatment, the release kinetics of DDS needs to be controlled in a defined manner, so that the concentration at the tumor site is within the therapeutic window. Thus, a DDS, with patient-specific release kinetics, is crucial for the improvement of therapy. Here, we present a computationally supported reservoir-based DDS (rDDS) development towards patient-specific release kinetics. The rDDS consists of a reservoir surrounded by a polydimethylsiloxane (PDMS) microchannel membrane. By tailoring the rDDS, in terms of membrane porosity, geometry, and drug concentration, the release profiles can be precisely adapted, with respect to the maximum concentration, release rate, and release time. The release is investigated using a model dye for varying parameters, leading to different distinct release profiles, with a maximum release of up to 60 days. Finally, a computational simulation, considering exemplary in vivo conditions (e.g., exchange of cerebrospinal fluid), is used to study the resulting drug release profiles, demonstrating the customizability of the system. The establishment of a computationally supported workflow, for development towards a patient-specific rDDS, in combination with the transfer to suitable drugs, could significantly improve the efficacy of localized therapy approaches.
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Valova G, Bogomyakova O, Tulupov A, Cherevko A. Influence of interaction of cerebral fluids on ventricular deformation: A mathematical approach. PLoS One 2022; 17:e0264395. [PMID: 35226657 PMCID: PMC8884699 DOI: 10.1371/journal.pone.0264395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 02/09/2022] [Indexed: 11/19/2022] Open
Abstract
This paper describes the effects of the interaction of cerebral fluids (arterial, capillary and venous blood, cerebrospinal fluid) on ventricular wall displacement and periventricular pressure using a mathematical multiphase poroelasticity model for the cerebral parenchyma. The interaction of cerebral fluids is given by a set of four numerical coefficients. A multiple linear regression with interaction is constructed that allows us to quantify the effect of these coefficients on the average ventricular wall displacement. The prevailing influence of an arterial-liquor component was observed. The sets of coefficients associated with such pathological conditions were found: normal pressure hydrocephalus, intracranial hypertension, and replacement ventriculomegaly under a prolonged hypoperfusion.
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Affiliation(s)
- Galina Valova
- Lavrentyev Institute of Hydrodynamics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
- * E-mail:
| | - Olga Bogomyakova
- Lavrentyev Institute of Hydrodynamics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
- International Tomography Center of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Andrey Tulupov
- Lavrentyev Institute of Hydrodynamics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
- International Tomography Center of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Alexander Cherevko
- Lavrentyev Institute of Hydrodynamics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
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Hladky SB, Barrand MA. The glymphatic hypothesis: the theory and the evidence. Fluids Barriers CNS 2022; 19:9. [PMID: 35115036 PMCID: PMC8815211 DOI: 10.1186/s12987-021-00282-z] [Citation(s) in RCA: 91] [Impact Index Per Article: 45.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 10/15/2021] [Indexed: 12/13/2022] Open
Abstract
The glymphatic hypothesis proposes a mechanism for extravascular transport into and out of the brain of hydrophilic solutes unable to cross the blood-brain barrier. It suggests that there is a circulation of fluid carrying solutes inwards via periarterial routes, through the interstitium and outwards via perivenous routes. This review critically analyses the evidence surrounding the mechanisms involved in each of these stages. There is good evidence that both influx and efflux of solutes occur along periarterial routes but no evidence that the principal route of outflow is perivenous. Furthermore, periarterial inflow of fluid is unlikely to be adequate to provide the outflow that would be needed to account for solute efflux. A tenet of the hypothesis is that flow sweeps solutes through the parenchyma. However, the velocity of any possible circulatory flow within the interstitium is too small compared to diffusion to provide effective solute movement. By comparison the earlier classical hypothesis describing extravascular transport proposed fluid entry into the parenchyma across the blood-brain barrier, solute movements within the parenchyma by diffusion, and solute efflux partly by diffusion near brain surfaces and partly carried by flow along "preferred routes" including perivascular spaces, white matter tracts and subependymal spaces. It did not suggest fluid entry via periarterial routes. Evidence is still incomplete concerning the routes and fate of solutes leaving the brain. A large proportion of the solutes eliminated from the parenchyma go to lymph nodes before reaching blood but the proportions delivered directly to lymph or indirectly via CSF which then enters lymph are as yet unclear. In addition, still not understood is why and how the absence of AQP4 which is normally highly expressed on glial endfeet lining periarterial and perivenous routes reduces rates of solute elimination from the parenchyma and of solute delivery to it from remote sites of injection. Neither the glymphatic hypothesis nor the earlier classical hypothesis adequately explain how solutes and fluid move into, through and out of the brain parenchyma. Features of a more complete description are discussed. All aspects of extravascular transport require further study.
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Affiliation(s)
- Stephen B. Hladky
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD UK
| | - Margery A. Barrand
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD UK
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Muccio M, Chu D, Minkoff L, Kulkarni N, Damadian B, Damadian RV, Ge Y. Upright versus supine MRI: effects of body position on craniocervical CSF flow. Fluids Barriers CNS 2021; 18:61. [PMID: 34952607 PMCID: PMC8710028 DOI: 10.1186/s12987-021-00296-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 12/11/2021] [Indexed: 01/17/2023] Open
Abstract
Background Cerebrospinal fluid (CSF) circulation between the brain and spinal canal, as part of the glymphatic system, provides homeostatic support to brain functions and waste clearance. Recently, it has been observed that CSF flow is strongly driven by cardiovascular brain pulsation, and affected by body orientation. The advancement of MRI has allowed for non-invasive examination of the CSF hydrodynamic properties. However, very few studies have addressed their relationship with body position (e.g., upright versus supine). It is important to understand how CSF hydrodynamics are altered by body position change in a single cardiac phase and how cumulative long hours staying in either upright or supine position can affect craniocervical CSF flow. Methods In this study, we investigate the changes in CSF flow at the craniocervical region with flow-sensitive MRI when subjects are moved from upright to supine position. 30 healthy volunteers were imaged in upright and supine positions using an upright MRI. The cranio-caudal and caudo-cranial CSF flow, velocity and stroke volume were measured at the C2 spinal level over one cardiac cycle using phase contrast MRI. Statistical analysis was performed to identify differences in CSF flow properties between the two positions. Results CSF stroke volume per cardiac cycle, representing CSF volume oscillating in and out of the cranium, was ~ 57.6% greater in supine (p < 0.0001), due to a ~ 83.8% increase in caudo-cranial CSF peak velocity during diastole (p < 0.0001) and extended systolic phase duration when moving from upright (0.25 ± 0.05 s) to supine (0.34 ± 0.08 s; p < 0.0001). Extrapolation to a 24 h timeframe showed significantly larger total CSF volume exchanged at C2 with 10 h spent supine versus only 5 h (p < 0.0001). Conclusions In summary, body position has significant effects on CSF flow in and out of the cranium, with more CSF oscillating in supine compared to upright position. Such difference was driven by an increased caudo-cranial diastolic CSF velocity and an increased systolic phase duration when moving from upright to supine position. Extrapolation to a 24 h timeframe suggests that more time spent in supine position increases total amount of CSF exchange, which may play a beneficial role in waste clearance in the brain.
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Affiliation(s)
- Marco Muccio
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Grossman School of Medicine, 660 First Avenue, 4th floor, New York, NY, 10016, USA
| | - David Chu
- FONAR Corporation, Melville, NY, USA
| | | | | | | | | | - Yulin Ge
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Grossman School of Medicine, 660 First Avenue, 4th floor, New York, NY, 10016, USA.
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15
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Ahmed A, UlHaq MU, Mustansar Z, Shaukat A, Margetts L. How growing tumour impacts intracranial pressure and deformation mechanics of brain. ROYAL SOCIETY OPEN SCIENCE 2021; 8:210165. [PMID: 34631118 PMCID: PMC8479368 DOI: 10.1098/rsos.210165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 09/02/2021] [Indexed: 06/13/2023]
Abstract
Brain is an actuator for control and coordination. When a pathology arises in cranium, it may leave a degenerative, disfiguring and destabilizing impact on brain physiology. However, the leading consequences of the same may vary from case to case. Tumour, in this context, is a special type of pathology which deforms brain parenchyma permanently. From translational perspective, deformation mechanics and pressures, specifically the intracranial cerebral pressure (ICP) in a tumour-housed brain, have not been addressed holistically in literature. This is an important area to investigate in neuropathy prognosis. To address this, we aim to solve the pressure mystery in a tumour-based brain in this study and present a fairly workable methodology. Using image-based finite-element modelling, we reconstruct a tumour-based brain and probe resulting deformations and pressures (ICP). Tumour is grown by dilating the voxel region by 16 and 30 mm uniformly. Cumulatively three cases are studied including an existing stage of the tumour. Pressures of cerebrospinal fluid due to its flow inside the ventricle region are also provided to make the model anatomically realistic. Comparison of obtained results unequivocally shows that as the tumour region increases its area and size, deformation pattern changes extensively and spreads throughout the brain volume with a greater concentration in tumour vicinity. Second, we conclude that ICP pressures inside the cranium do increase substantially; however, they still remain under the normal values (15 mmHg). In the end, a correlation relationship of ICP mechanics and tumour is addressed. From a diagnostic purpose, this result also explains why generally a tumour in its initial stage does not show symptoms because the required ICP threshold has not been crossed. We finally conclude that even at low ICP values, substantial deformation progression inside the cranium is possible. This may result in plastic deformation, midline shift etc. in the brain.
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Affiliation(s)
- Ali Ahmed
- Department of Biomedical Engineering and Sciences, School of Mechanical and Manufacturing Engineering (SMME), National university of Sciences and Technology (NUST), Islamabad 44000, Pakistan
| | - Muhammad Uzair UlHaq
- Department of Biomedical Engineering and Sciences, School of Mechanical and Manufacturing Engineering (SMME), National university of Sciences and Technology (NUST), Islamabad 44000, Pakistan
| | - Zartasha Mustansar
- Department of Computational Engineering, Research Center of Modeling and Simulation (RCMS), National university of Sciences and Technology (NUST), Islamabad 44000, Pakistan
| | - Arslan Shaukat
- Department of Computer and Software Engineering, College of Electrical and Mechanical Engineering, National university of Sciences and Technology (NUST), Islamabad 44000, Pakistan
| | - Lee Margetts
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, UK
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16
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Miyazaki Y, Usawa M, Kawai S, Yee J, Muto M, Tagawa Y. Dynamic mechanical interaction between injection liquid and human tissue simulant induced by needle-free injection of a highly focused microjet. Sci Rep 2021; 11:14544. [PMID: 34267280 PMCID: PMC8282861 DOI: 10.1038/s41598-021-94018-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 07/01/2021] [Indexed: 12/15/2022] Open
Abstract
This study investigated the fluid-tissue interaction of needle-free injection by evaluating the dynamics of the cavity induced in body-tissue simulant and the resulting unsteady mechanical stress field. Temporal evolution of cavity shape, stress intensity field, and stress vector field during the injection of a conventional injection needle, a proposed highly focused microjet (tip diameter much smaller than capillary nozzle), and a typical non-focused microjet in gelatin were measured using a state-of-the-art high-speed polarization camera, at a frame rate up to 25,000 f.p.s. During the needle injection performed by an experienced nurse, high stress intensity lasted for an order of seconds (from beginning of needle penetration until end of withdrawal), which is much longer than the order of milliseconds during needle-free injections, causing more damage to the body tissue. The cavity induced by focused microjet resembled a funnel which had a narrow tip that penetrated deep into tissue simulant, exerting shear stress in low intensity which diffused through shear stress wave. Whereas the cavity induced by non-focused microjet rebounded elastically (quickly expanded into a sphere and shrank into a small cavity which remained), exerting compressive stress on tissue simulant in high stress intensity. By comparing the distribution of stress intensity, tip shape of the focused microjet contributed to a better performance than non-focused microjet with its ability to penetrate deep while only inducing stress at lower intensity. Dynamic mechanical interaction revealed in this research uncovered the importance of the jet shape for the development of minimally invasive medical devices.
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Affiliation(s)
- Yuta Miyazaki
- Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Japan
| | - Masashi Usawa
- Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Japan
| | - Shuma Kawai
- Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Japan
| | - Jingzu Yee
- Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Japan
| | - Masakazu Muto
- Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Japan
| | - Yoshiyuki Tagawa
- Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Japan.
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17
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Development, calibration, and testing of 3D amplified MRI (aMRI) for the quantification of intrinsic brain motion. BRAIN MULTIPHYSICS 2021. [DOI: 10.1016/j.brain.2021.100022] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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18
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Gholampour S, Fatouraee N. Boundary conditions investigation to improve computer simulation of cerebrospinal fluid dynamics in hydrocephalus patients. Commun Biol 2021; 4:394. [PMID: 33758352 PMCID: PMC7988041 DOI: 10.1038/s42003-021-01920-w] [Citation(s) in RCA: 15] [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: 10/13/2020] [Accepted: 03/01/2021] [Indexed: 01/31/2023] Open
Abstract
Three-D head geometrical models of eight healthy subjects and 11 hydrocephalus patients were built using their CINE phase-contrast MRI data and used for computer simulations under three different inlet/outlet boundary conditions (BCs). The maximum cerebrospinal fluid (CSF) pressure and the ventricular system volume were more effective and accurate than the other parameters in evaluating the patients' conditions. In constant CSF pressure, the computational patient models were 18.5% more sensitive to CSF volume changes in the ventricular system under BC "C". Pulsatile CSF flow rate diagrams were used for inlet and outlet BCs of BC "C". BC "C" was suggested to evaluate the intracranial compliance of the hydrocephalus patients. The results suggested using the computational fluid dynamic (CFD) method and the fully coupled fluid-structure interaction (FSI) method for the CSF dynamic analysis in patients with external and internal hydrocephalus, respectively.
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Affiliation(s)
- Seifollah Gholampour
- Department of Biomedical Engineering, North Tehran Branch, Islamic Azad University, Tehran, Iran.
| | - Nasser Fatouraee
- Biological Fluid Mechanics Research Laboratory, Biomechanics Department, Biomedical Engineering Faculty, Amirkabir University of Technology, Tehran, Iran
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19
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Lemmerman LR, Balch MHH, Moore JT, Alzate-Correa D, Rincon-Benavides MA, Salazar-Puerta A, Gnyawali S, Harris HN, Lawrence W, Ortega-Pineda L, Wilch L, Risser IB, Maxwell AJ, Duarte-Sanmiguel S, Dodd D, Guio-Vega GP, McTigue DM, Arnold WD, Nimjee SM, Sen CK, Khanna S, Rink C, Higuita-Castro N, Gallego-Perez D. Nanotransfection-based vasculogenic cell reprogramming drives functional recovery in a mouse model of ischemic stroke. SCIENCE ADVANCES 2021; 7:eabd4735. [PMID: 33741587 PMCID: PMC7978431 DOI: 10.1126/sciadv.abd4735] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 01/22/2021] [Indexed: 05/14/2023]
Abstract
Ischemic stroke causes vascular and neuronal tissue deficiencies that could lead to substantial functional impairment and/or death. Although progenitor-based vasculogenic cell therapies have shown promise as a potential rescue strategy following ischemic stroke, current approaches face major hurdles. Here, we used fibroblasts nanotransfected with Etv2, Foxc2, and Fli1 (EFF) to drive reprogramming-based vasculogenesis, intracranially, as a potential therapy for ischemic stroke. Perfusion analyses suggest that intracranial delivery of EFF-nanotransfected fibroblasts led to a dose-dependent increase in perfusion 14 days after injection. MRI and behavioral tests revealed ~70% infarct resolution and up to ~90% motor recovery for mice treated with EFF-nanotransfected fibroblasts. Immunohistological analysis confirmed increases in vascularity and neuronal cellularity, as well as reduced glial scar formation in response to treatment with EFF-nanotransfected fibroblasts. Together, our results suggest that vasculogenic cell therapies based on nanotransfection-driven (i.e., nonviral) cellular reprogramming represent a promising strategy for the treatment of ischemic stroke.
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Affiliation(s)
- Luke R Lemmerman
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA
| | - Maria H H Balch
- Department of Neurosurgery, The Ohio State University, Columbus, OH 43210, USA
| | - Jordan T Moore
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA
| | - Diego Alzate-Correa
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA
| | | | - Ana Salazar-Puerta
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA
| | - Surya Gnyawali
- Department of Neurosurgery, The Ohio State University, Columbus, OH 43210, USA
| | - Hallie N Harris
- Department of Neurosurgery, The Ohio State University, Columbus, OH 43210, USA
| | - William Lawrence
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Lilibeth Ortega-Pineda
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA
| | - Lauren Wilch
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Ian B Risser
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA
| | - Aidan J Maxwell
- Department of Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Silvia Duarte-Sanmiguel
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA
- OSU Nutrition, The Ohio State University, Columbus, OH 43210, USA
| | - Daniel Dodd
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Gina P Guio-Vega
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA
- Department of Medicine, National University of Colombia, Bogotá, Colombia
| | - Dana M McTigue
- Department of Neuroscience, The Ohio State University, Columbus, OH 43210, USA
| | - W David Arnold
- Department of Neurology, The Ohio State University, Columbus, OH 43210, USA
| | - Shahid M Nimjee
- Department of Neurosurgery, The Ohio State University, Columbus, OH 43210, USA
| | - Chandan K Sen
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Savita Khanna
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Cameron Rink
- Department of Neurosurgery, The Ohio State University, Columbus, OH 43210, USA
| | - Natalia Higuita-Castro
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA.
- Department of Surgery, The Ohio State University, Columbus, OH 43210, USA
| | - Daniel Gallego-Perez
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA.
- Department of Surgery, The Ohio State University, Columbus, OH 43210, USA
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20
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MISRA JC, DANDAPAT S, ADHIKARY SD. WAVE PROPAGATION IN THE CRANIUM AND THE CEREBROSPINAL FLUID. J MECH MED BIOL 2021. [DOI: 10.1142/s0219519420500451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this paper, wave propagation in head generated by a local axisymmetric impact on its outer surface is studied. The skull material is treated as isotropic and homogeneous, but presence of the cerebrospinal fluid (considered as a compressible but inviscid irrotational fluid) inside the cranium has been accounted for in the analysis. Some numerical results obtained on the basis of the analytical study, are also presented.
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Affiliation(s)
- J. C. MISRA
- Centre for Healthcare Science and Technology, Indian Institute of Engineering Science and Technology, Howrah 711103, India
| | - S. DANDAPAT
- Indian Institute of Technology, Kharagpur, India
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21
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Dur AH, Tang T, Viviano S, Sekuri A, Willsey HR, Tagare HD, Kahle KT, Deniz E. In Xenopus ependymal cilia drive embryonic CSF circulation and brain development independently of cardiac pulsatile forces. Fluids Barriers CNS 2020; 17:72. [PMID: 33308296 PMCID: PMC7731788 DOI: 10.1186/s12987-020-00234-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/28/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Hydrocephalus, the pathological expansion of the cerebrospinal fluid (CSF)-filled cerebral ventricles, is a common, deadly disease. In the adult, cardiac and respiratory forces are the main drivers of CSF flow within the brain ventricular system to remove waste and deliver nutrients. In contrast, the mechanics and functions of CSF circulation in the embryonic brain are poorly understood. This is primarily due to the lack of model systems and imaging technology to study these early time points. Here, we studied embryos of the vertebrate Xenopus with optical coherence tomography (OCT) imaging to investigate in vivo ventricular and neural development during the onset of CSF circulation. METHODS Optical coherence tomography (OCT), a cross-sectional imaging modality, was used to study developing Xenopus tadpole brains and to dynamically detect in vivo ventricular morphology and CSF circulation in real-time, at micrometer resolution. The effects of immobilizing cilia and cardiac ablation were investigated. RESULTS In Xenopus, using OCT imaging, we demonstrated that ventriculogenesis can be tracked throughout development until the beginning of metamorphosis. We found that during Xenopus embryogenesis, initially, CSF fills the primitive ventricular space and remains static, followed by the initiation of the cilia driven CSF circulation where ependymal cilia create a polarized CSF flow. No pulsatile flow was detected throughout these tailbud and early tadpole stages. As development progressed, despite the emergence of the choroid plexus in Xenopus, cardiac forces did not contribute to the CSF circulation, and ciliary flow remained the driver of the intercompartmental bidirectional flow as well as the near-wall flow. We finally showed that cilia driven flow is crucial for proper rostral development and regulated the spatial neural cell organization. CONCLUSIONS Our data support a paradigm in which Xenopus embryonic ventriculogenesis and rostral brain development are critically dependent on ependymal cilia-driven CSF flow currents that are generated independently of cardiac pulsatile forces. Our work suggests that the Xenopus ventricular system forms a complex cilia-driven CSF flow network which regulates neural cell organization. This work will redirect efforts to understand the molecular regulators of embryonic CSF flow by focusing attention on motile cilia rather than other forces relevant only to the adult.
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Affiliation(s)
- A H Dur
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06510, USA
- Acibadem Mehmet Ali Aydinlar University School of Medicine, Istanbul, Turkey
| | - T Tang
- Department of Radiology and Biomedical Imaging, Yale University, 300 Cedar St, New Haven, CT, 06510, USA
| | - S Viviano
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06510, USA
- Pediatric Genomics Discovery Program, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06510, USA
| | - A Sekuri
- Acibadem Mehmet Ali Aydinlar University School of Medicine, Istanbul, Turkey
| | - H R Willsey
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - H D Tagare
- Department of Radiology and Biomedical Imaging, Yale University, 300 Cedar St, New Haven, CT, 06510, USA
| | - K T Kahle
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06510, USA
- Department of Neurosurgery and Cellular & Molecular Physiology, and Centers for Mendelian Genomics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06510, USA
| | - E Deniz
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06510, USA.
- Pediatric Genomics Discovery Program, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06510, USA.
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22
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Bjorkli C, Sandvig A, Sandvig I. Bridging the Gap Between Fluid Biomarkers for Alzheimer's Disease, Model Systems, and Patients. Front Aging Neurosci 2020; 12:272. [PMID: 32982716 PMCID: PMC7492751 DOI: 10.3389/fnagi.2020.00272] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/06/2020] [Indexed: 12/12/2022] Open
Abstract
Alzheimer’s disease (AD) is a debilitating neurodegenerative disease characterized by the accumulation of two proteins in fibrillar form: amyloid-β (Aβ) and tau. Despite decades of intensive research, we cannot yet pinpoint the exact cause of the disease or unequivocally determine the exact mechanism(s) underlying its progression. This confounds early diagnosis and treatment of the disease. Cerebrospinal fluid (CSF) biomarkers, which can reveal ongoing biochemical changes in the brain, can help monitor developing AD pathology prior to clinical diagnosis. Here we review preclinical and clinical investigations of commonly used biomarkers in animals and patients with AD, which can bridge translation from model systems into the clinic. The core AD biomarkers have been found to translate well across species, whereas biomarkers of neuroinflammation translate to a lesser extent. Nevertheless, there is no absolute equivalence between biomarkers in human AD patients and those examined in preclinical models in terms of revealing key pathological hallmarks of the disease. In this review, we provide an overview of current but also novel AD biomarkers and how they relate to key constituents of the pathological cascade, highlighting confounding factors and pitfalls in interpretation, and also provide recommendations for standardized procedures during sample collection to enhance the translational validity of preclinical AD models.
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Affiliation(s)
- Christiana Bjorkli
- Sandvig Group, Department of Neuromedicine and Movement Science, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Axel Sandvig
- Sandvig Group, Department of Neuromedicine and Movement Science, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.,Institute of Neuromedicine and Movement Science, Department of Neurology, St. Olavs Hospital, Trondheim, Norway.,Department of Pharmacology and Clinical Neurosciences, Division of Neuro, Head, and Neck, University Hospital of Umeå, Umeå, Sweden
| | - Ioanna Sandvig
- Sandvig Group, Department of Neuromedicine and Movement Science, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
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Kerscher SR, Schweizer LL, Haas-Lude K, Bevot A, Schuhmann MU. Changes of third ventricle diameter (TVD) mirror changes of the entire ventricular system at acute shunt failure and after shunt revision in pediatric hydrocephalus. Childs Nerv Syst 2020; 36:2033-2039. [PMID: 32215715 DOI: 10.1007/s00381-020-04570-1] [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: 01/11/2020] [Accepted: 03/06/2020] [Indexed: 11/28/2022]
Abstract
PURPOSE In hydrocephalic children, regular investigations of the ventricles are important for initial diagnosis and after initial treatment. Our recent study showed that changes of the third ventricle diameter (TVD) reliably reflect changes of the entire ventricular system at diagnosis and following initial therapy. This study compares changes of TVD with changes of ventricle indices at acute shunt failure and after shunt revision in hydrocephalic children. METHODS A total of 117 children with hydrocephalus were included in this study. MRI/CT images of 30 children were evaluated at the time of acute shunt dysfunction and after subsequent shunt revision. Measurements included axial TVD and three standard measures of lateral ventricles (Evans index, frontal occipital horn ratio (FOHR), and cella media index (CMI)). In 97 children, correlation between axial and coronal/diagonal TVD was evaluated at the time of initial diagnosis of hydrocephalus. RESULTS At acute shunt dysfunction, the best linear correlation was found between TVD and CMI (r = 0.702, p < 0.01). Changes of TVD correlated very well to changes of FOHR (r = 0.74, p < 0.01) after shunt revision. The correlation between axial and coronal/diagonal TVD was outstanding (r = 0.995, p < 0.01). CONCLUSION TVD showed a significant correlation with all lateral ventricle indices at acute shunt dysfunction and after shunt revision. It is therefore not only an excellent mirror of ventricular changes at initial hydrocephalus diagnosis and therapy, but it can also reliably reflect changes of the ventricular system in relevant clinical situations associated with the lifelong treatment of pediatric hydrocephalus.
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Affiliation(s)
- Susanne R Kerscher
- Pediatric Neurosurgery, Department of Neurosurgery, University Hospital of Tuebingen, Hoppe-Seyler-Str.3, 72076, Tübingen, Germany. .,Department of Neurosurgery, University Hospital of Tuebingen, Tübingen, Germany.
| | - Louise L Schweizer
- Pediatric Neurosurgery, Department of Neurosurgery, University Hospital of Tuebingen, Hoppe-Seyler-Str.3, 72076, Tübingen, Germany
| | - Karin Haas-Lude
- Department of Pediatric Neurology and Developmental Medicine, Children's Hospital, University of Tuebingen, Tübingen, Germany
| | - Andrea Bevot
- Department of Pediatric Neurology and Developmental Medicine, Children's Hospital, University of Tuebingen, Tübingen, Germany
| | - Martin U Schuhmann
- Pediatric Neurosurgery, Department of Neurosurgery, University Hospital of Tuebingen, Hoppe-Seyler-Str.3, 72076, Tübingen, Germany.,Department of Neurosurgery, University Hospital of Tuebingen, Tübingen, Germany
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24
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Kedarasetti RT, Turner KL, Echagarruga C, Gluckman BJ, Drew PJ, Costanzo F. Functional hyperemia drives fluid exchange in the paravascular space. Fluids Barriers CNS 2020; 17:52. [PMID: 32819402 PMCID: PMC7441569 DOI: 10.1186/s12987-020-00214-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 08/09/2020] [Indexed: 12/20/2022] Open
Abstract
The brain lacks a conventional lymphatic system to remove metabolic waste. It has been proposed that directional fluid movement through the arteriolar paravascular space (PVS) promotes metabolite clearance. We performed simulations to examine if arteriolar pulsations and dilations can drive directional CSF flow in the PVS and found that arteriolar wall movements do not drive directional CSF flow. We propose an alternative method of metabolite clearance from the PVS, namely fluid exchange between the PVS and the subarachnoid space (SAS). In simulations with compliant brain tissue, arteriolar pulsations did not drive appreciable fluid exchange between the PVS and the SAS. However, when the arteriole dilated, as seen during functional hyperemia, there was a marked exchange of fluid. Simulations suggest that functional hyperemia may serve to increase metabolite clearance from the PVS. We measured blood vessels and brain tissue displacement simultaneously in awake, head-fixed mice using two-photon microscopy. These measurements showed that brain deforms in response to pressure changes in PVS, consistent with our simulations. Our results show that the deformability of the brain tissue needs to be accounted for when studying fluid flow and metabolite transport.
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Affiliation(s)
- Ravi Teja Kedarasetti
- Center for Neural Engineering, The Pennsylvania State University, University Park, PA, USA
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, USA
| | - Kevin L Turner
- Center for Neural Engineering, The Pennsylvania State University, University Park, PA, USA
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA
| | - Christina Echagarruga
- Center for Neural Engineering, The Pennsylvania State University, University Park, PA, USA
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA
| | - Bruce J Gluckman
- Center for Neural Engineering, The Pennsylvania State University, University Park, PA, USA
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, USA
- Department of Neurosurgery, The Pennsylvania State University, University Park, PA, USA
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA
| | - Patrick J Drew
- Center for Neural Engineering, The Pennsylvania State University, University Park, PA, USA.
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, USA.
- Department of Neurosurgery, The Pennsylvania State University, University Park, PA, USA.
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA.
| | - Francesco Costanzo
- Center for Neural Engineering, The Pennsylvania State University, University Park, PA, USA.
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, USA.
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA.
- Department of Mathematics, The Pennsylvania State University, University Park, PA, USA.
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Mandel M, Ferreira da Silva IA, Paiva W, Li Y, Steinberg GK, Teixeira MJ. Minimally invasive foramen magnum durectomy and obexostomy for treatment of craniocervical junction-related syringomyelia in adults: case series and midterm follow-up. J Neurosurg Spine 2020; 33:148-157. [PMID: 32302978 DOI: 10.3171/2020.2.spine2032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 02/10/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Craniocervical junction-related syringomyelia (CCJS) is the most common form of syringomyelia. Approximately 30% of patients treated with foramen magnum decompression (FMD) will show persistence, recurrence, or progression of the syrinx. The authors present a pilot study with a new minimally invasive surgery technique targeting the pathophysiology of CCJS in adult patients. METHODS The authors retrospectively analyzed the clinical and radiological features of a consecutive series of patients treated for CCJS. An FMD and FM durectomy were performed through a 1.5- to 2-cm skin incision. Then arachnoid adhesions were cleared, creating a permanent communication from the fourth ventricle to the new paraspinal extradural cavity (obexostomy) and with the spinal subarachnoid space. The hypothesis was that the new CSF pouch acts like a pressure leak, interrupting the CCJS pathogenesis. RESULTS Twenty-four patients (13 female, 21-61 years old) were treated between 2014 and 2018. The etiology of CCJS was Chiari malformation type I (CM-I) in 20 patients (83.3%), Chiari malformation type 0 (CM-0) in 2 patients (8.3%), and CCJ arachnoiditis in 2 patients (8.3%). Two patients underwent reoperations after failed FMD for CM-I at other institutions. No major surgical complication occurred. One patient had postoperative meningitis with no CSF fistula. On postoperative MRI, shrinkage of the syrinx was seen in all patients. No patients experienced recurrence of the CCJS. No patient required a subsequent operation. The mean duration of surgery was 72 ± 11 minutes (mean ± SD), and blood loss was 35-80 ml (mean 51 ml). Follow-up ranged from 12 to 58 months. The average overall improvement in modified Japanese Orthopaedic Association scores was 10% (p < 0.001). The Odom scale showed that 19 patients (79.1%) were satisfied, 4 (16.7%) remained the same, and 1 (4.2%) reported a poor outcome. All patients experienced postoperative improvement in perception of quality of life (p < 0.001). CONCLUSIONS Minimally invasive FM durectomy and obexostomy is a safe and effective treatment for CCJS and for patients who have not responded to other treatment.
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Affiliation(s)
- Mauricio Mandel
- 1Department of Neurosurgery, Hospital das Clínicas of University of São Paulo Medical School, São Paulo
- 2Hospital Israelita Albert Einstein, São Paulo, Brazil; and
- 3Department of Neurosurgery, Stanford University School of Medicine, Stanford, California
| | - Igor Araújo Ferreira da Silva
- 1Department of Neurosurgery, Hospital das Clínicas of University of São Paulo Medical School, São Paulo
- 2Hospital Israelita Albert Einstein, São Paulo, Brazil; and
| | - Wellingson Paiva
- 1Department of Neurosurgery, Hospital das Clínicas of University of São Paulo Medical School, São Paulo
| | - Yiping Li
- 3Department of Neurosurgery, Stanford University School of Medicine, Stanford, California
| | - Gary K Steinberg
- 3Department of Neurosurgery, Stanford University School of Medicine, Stanford, California
| | - Manoel Jacobsen Teixeira
- 1Department of Neurosurgery, Hospital das Clínicas of University of São Paulo Medical School, São Paulo
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Ejikeme T, de Castro GC, Ripple K, Chen Y, Giamberardino C, Bartuska A, Smilnak G, Marius C, Boua JV, Chongsathidkiet P, Hodges S, Pagadala P, Verbick LZ, McCabe AR, Lad SP. Evaluation of neurapheresis therapy in vitro: a novel approach for the treatment of leptomeningeal metastases. Neurooncol Adv 2020; 2:vdaa052. [PMID: 32642705 PMCID: PMC7236387 DOI: 10.1093/noajnl/vdaa052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background Leptomeningeal metastases (LM), late-stage cancer when malignant cells migrate to the subarachnoid space (SAS), have an extremely poor prognosis. Current treatment regimens fall short in effectively reducing SAS tumor burden. Neurapheresis therapy is a novel approach employing filtration and enhanced circulation of the cerebrospinal fluid (CSF). Here, we examine the in vitro use of neurapheresis therapy as a novel, adjunctive treatment option for LM by filtering cells and augmenting the distribution of drugs that may have the potential to enhance the current clinical approach. Methods Clinically relevant concentrations of VX2 carcinoma cells were suspended in artificial CSF. The neurapheresis system’s ability to clear VX2 carcinoma cells was tested with and without the chemotherapeutic presence (methotrexate [MTX]). The VX2 cell concentration following each filtration cycle and the number of cycles required to reach the limit of detection were calculated. The ability of neurapheresis therapy to circulate, distribute, and maintain therapeutic levels of MTX was assessed using a cranial–spinal model of the SAS. The distribution of a 6 mg dose was monitored for 48 h. An MTX-specific ELISA measured drug concentration at ventricular, cervical, and lumbar sites in the model over time. Results In vitro filtration of VX2 cancer cells with neurapheresis therapy alone resulted in a 2.3-log reduction in cancer cell concentration in 7.5 h and a 2.4-log reduction in live-cancer cell concentration in 7.5 h when used with MTX. Cranial–spinal model experiments demonstrated the ability of neurapheresis therapy to enhance the circulation of MTX in CSF along the neuraxis. Conclusion Neurapheresis has the potential to act as an adjunct therapy for LM patients and significantly improve the standard of care.
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Affiliation(s)
- Tiffany Ejikeme
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | - George C de Castro
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Katelyn Ripple
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Yutong Chen
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Charles Giamberardino
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Andrew Bartuska
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Gordon Smilnak
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Choiselle Marius
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Jane-Valeriane Boua
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | | | - Sarah Hodges
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Promila Pagadala
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | | | | | - Shivanand P Lad
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
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Debnam JM, Said RB, Liu HH, Sun J, Wang J, Wei W, Suki D, Mayer RR, Chi TL, Ketonen L, Guha-Thakurta N, Weinberg JS. Ventricular apparent diffusion coefficient measurements in patients with neoplastic leptomeningeal disease. Cancer Imaging 2020; 20:41. [PMID: 32600415 PMCID: PMC7322838 DOI: 10.1186/s40644-020-00305-2] [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: 12/02/2019] [Accepted: 04/01/2020] [Indexed: 12/05/2022] Open
Abstract
Background To test the hypothesis that intraventricular ADC values can be used to determine the presence of neoplastic leptomeningeal disease (LMD). Materials and methods ADC values were measured at multiple sites in the ventricular system in 32 patients with cytologically-proven LMD and 40 control subjects. Multiple linear regression analysis was used to determine the mean difference of ADCs between the LMD and control groups after adjusting for ventricle size and tumor type. Receiver operating characteristics (ROC) analysis was performed and optimal ADC value cut-off point for predicting the presence of LMD. ADC was compared to T1 enhancement and FLAIR signal hyperintensity for determining the presence of LMD. Results After adjusting for ventricular volume and tumor type, the mid body of lateral ventricles showed no significant difference in ventricular volume and a significant difference in ADC values between the control and LMD groups (p > 0.05). In the mid-body of the right lateral ventricle the AUC was 0.69 (95% CI 0.57–0.81) with an optimal ADC cut off point of 3.22 × 10− 9 m2/s (sensitivity, specificity; 0.72, 0.68). In the mid-body of left lateral ventricle the AUC was 0.7 (95% CI 0.58–0.82) with an optimal cut-off point of 3.23 × 10− 9 m2/s (0.81, 0.62). Using an average value of HU measurements in the lateral ventricles the AUC was 0.73 (95% CI 0.61–0.84) with an optimal cut off point was 3.11 × 10− 9 m2/s (0.78, 0.65). Compared to the T1 post-contrast series, ADC was predictive of the presence of LMD in the mid-body of the left lateral ventricle (p = 0.036). Conclusion Complex interactions affect ADC measurements in patients with LMD. ADC values in the lateral ventricles may provide non-invasive clues to the presence of LMD.
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Affiliation(s)
- James M Debnam
- Department of Neuroradiology, The University of Texas MD Anderson Cancer Center, 1400 Pressler Blvd., Unit 1482, Houston, TX, 77030, USA.
| | - Ryan B Said
- Department of Neuroradiology, The University of Texas MD Anderson Cancer Center, 1400 Pressler Blvd., Unit 1482, Houston, TX, 77030, USA
| | - Heng-Hsiao Liu
- Department of Neuroradiology, The University of Texas MD Anderson Cancer Center, 1400 Pressler Blvd., Unit 1482, Houston, TX, 77030, USA
| | - Jia Sun
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jihong Wang
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Wei Wei
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Dima Suki
- Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Rory R Mayer
- Department of Neurosurgery, University of California San Francisco, San Francisco, CA, USA
| | - T Linda Chi
- Department of Neuroradiology, The University of Texas MD Anderson Cancer Center, 1400 Pressler Blvd., Unit 1482, Houston, TX, 77030, USA
| | - Leena Ketonen
- Department of Neuroradiology, The University of Texas MD Anderson Cancer Center, 1400 Pressler Blvd., Unit 1482, Houston, TX, 77030, USA
| | - Nandita Guha-Thakurta
- Department of Neuroradiology, The University of Texas MD Anderson Cancer Center, 1400 Pressler Blvd., Unit 1482, Houston, TX, 77030, USA
| | - Jeffrey S Weinberg
- Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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Adams AL, Viergever MA, Luijten PR, Zwanenburg JJM. Validating faster DENSE measurements of cardiac-induced brain tissue expansion as a potential tool for investigating cerebral microvascular pulsations. Neuroimage 2019; 208:116466. [PMID: 31843712 DOI: 10.1016/j.neuroimage.2019.116466] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 12/13/2019] [Indexed: 11/17/2022] Open
Abstract
Displacement Encoding with Stimulated Echoes (DENSE) has recently shown potential for measuring cardiac-induced cerebral volumetric strain in the human brain. As such, it may provide a powerful tool for investigating the cerebral small vessels. However, further development and validation are necessary. This study aims, first, to validate a retrospectively-gated implementation of the DENSE method for assessing brain tissue pulsations as a physiological marker, and second, to use the acquired measurements to explore intracranial volume dynamics. We acquired repeated measurements of cerebral volumetric strain in 8 healthy subjects, and internally validated these measurements by comparing them to spinal CSF stroke volumes obtained in the same scan session. Peak volumetric strain was found to be highly repeatable between scan sessions. First/second measured peak volumetric strains were: (6.4 ± 1.7)x10-4/(6.7 ± 1.6)x10-4 for whole brain, (9.5 ± 2.5)x10-4/(9.6 ± 2.4)x10-4 for grey matter, and (4.4 ± 1.7)x10-4/(4.1 ± 0.8)x10-4 for white matter. Grey matter showed significantly higher peak strain (p < 0.001) and earlier time-to-peak strain (p < 0.02) than white matter. An approximately linear relationship was found between CSF and brain tissue volume pulsations over the cardiac cycle (mean slope and R2 of 0.88 ± 0.23 and 0.89 ± 0.07, respectively). The close similarity between CSF and brain tissue volume pulsations implies limited contributions from large intracranial vessel pulsations, providing further evidence for venous compression as an additional mechanism for maintaining stable intracranial pressures over the cardiac cycle. Cerebral pulsatility showed consistent inter-subject peak values in healthy subjects, and was strongly correlated to CSF stroke volumes. These results strengthen the potential of brain tissue volumetric strain as a means for investigating the intracranial dynamics of the ageing brain in normal or diseased states.
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Affiliation(s)
- Ayodeji L Adams
- Department of Radiology, University Medical Center Utrecht, E 01.132, Heidelberglaan 100, 3584 CX, Utrecht, the Netherlands.
| | - Max A Viergever
- Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, the Netherlands.
| | - Peter R Luijten
- Department of Radiology, University Medical Center Utrecht, E 01.132, Heidelberglaan 100, 3584 CX, Utrecht, the Netherlands.
| | - Jaco J M Zwanenburg
- Department of Radiology, University Medical Center Utrecht, E 01.132, Heidelberglaan 100, 3584 CX, Utrecht, the Netherlands.
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Sindeeva OA, Verkhovskii RA, Sarimollaoglu M, Afanaseva GA, Fedonnikov AS, Osintsev EY, Kurochkina EN, Gorin DA, Deyev SM, Zharov VP, Galanzha EI. New Frontiers in Diagnosis and Therapy of Circulating Tumor Markers in Cerebrospinal Fluid In Vitro and In Vivo. Cells 2019; 8:E1195. [PMID: 31581745 PMCID: PMC6830088 DOI: 10.3390/cells8101195] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 09/21/2019] [Accepted: 09/26/2019] [Indexed: 02/07/2023] Open
Abstract
One of the greatest challenges in neuro-oncology is diagnosis and therapy (theranostics) of leptomeningeal metastasis (LM), brain metastasis (BM) and brain tumors (BT), which are associated with poor prognosis in patients. Retrospective analyses suggest that cerebrospinal fluid (CSF) is one of the promising diagnostic targets because CSF passes through central nervous system, harvests tumor-related markers from brain tissue and, then, delivers them into peripheral parts of the human body where CSF can be sampled using minimally invasive and routine clinical procedure. However, limited sensitivity of the established clinical diagnostic cytology in vitro and MRI in vivo together with minimal therapeutic options do not provide patient care at early, potentially treatable, stages of LM, BM and BT. Novel technologies are in demand. This review outlines the advantages, limitations and clinical utility of emerging liquid biopsy in vitro and photoacoustic flow cytometry (PAFC) in vivo for assessment of CSF markers including circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), microRNA (miRNA), proteins, exosomes and emboli. The integration of in vitro and in vivo methods, PAFC-guided theranostics of single CTCs and targeted drug delivery are discussed as future perspectives.
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Affiliation(s)
- Olga A. Sindeeva
- Laboratory of Biomedical Photoacoustics, Saratov State University, 83 Astrakhanskaya St, 410012 Saratov, Russia; (O.A.S.); (R.A.V.); (G.A.A.); (A.S.F.); (E.Y.O.); (E.N.K.); (V.P.Z.)
| | - Roman A. Verkhovskii
- Laboratory of Biomedical Photoacoustics, Saratov State University, 83 Astrakhanskaya St, 410012 Saratov, Russia; (O.A.S.); (R.A.V.); (G.A.A.); (A.S.F.); (E.Y.O.); (E.N.K.); (V.P.Z.)
| | - Mustafa Sarimollaoglu
- Arkansas Nanomedicine Center & Winthrop P. Rockefeller Cancer Institute, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA;
| | - Galina A. Afanaseva
- Laboratory of Biomedical Photoacoustics, Saratov State University, 83 Astrakhanskaya St, 410012 Saratov, Russia; (O.A.S.); (R.A.V.); (G.A.A.); (A.S.F.); (E.Y.O.); (E.N.K.); (V.P.Z.)
- Saratov State Medical University, 112 Bolshaya Kazachia St., 410012 Saratov, Russia
| | - Alexander S. Fedonnikov
- Laboratory of Biomedical Photoacoustics, Saratov State University, 83 Astrakhanskaya St, 410012 Saratov, Russia; (O.A.S.); (R.A.V.); (G.A.A.); (A.S.F.); (E.Y.O.); (E.N.K.); (V.P.Z.)
- Saratov State Medical University, 112 Bolshaya Kazachia St., 410012 Saratov, Russia
| | - Evgeny Yu. Osintsev
- Laboratory of Biomedical Photoacoustics, Saratov State University, 83 Astrakhanskaya St, 410012 Saratov, Russia; (O.A.S.); (R.A.V.); (G.A.A.); (A.S.F.); (E.Y.O.); (E.N.K.); (V.P.Z.)
- Saratov State Medical University, 112 Bolshaya Kazachia St., 410012 Saratov, Russia
| | - Elena N. Kurochkina
- Laboratory of Biomedical Photoacoustics, Saratov State University, 83 Astrakhanskaya St, 410012 Saratov, Russia; (O.A.S.); (R.A.V.); (G.A.A.); (A.S.F.); (E.Y.O.); (E.N.K.); (V.P.Z.)
- Saratov State Medical University, 112 Bolshaya Kazachia St., 410012 Saratov, Russia
| | - Dmitry A. Gorin
- Laboratory of Biophotonics, Skolkovo Institute of Science and Technology, 3 Nobelya Str., 121205 Moscow, Russia;
| | - Sergey M. Deyev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya St., 16/10, Moscow 117997, Russia;
| | - Vladimir P. Zharov
- Laboratory of Biomedical Photoacoustics, Saratov State University, 83 Astrakhanskaya St, 410012 Saratov, Russia; (O.A.S.); (R.A.V.); (G.A.A.); (A.S.F.); (E.Y.O.); (E.N.K.); (V.P.Z.)
- Arkansas Nanomedicine Center & Winthrop P. Rockefeller Cancer Institute, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA;
| | - Ekaterina I. Galanzha
- Laboratory of Biomedical Photoacoustics, Saratov State University, 83 Astrakhanskaya St, 410012 Saratov, Russia; (O.A.S.); (R.A.V.); (G.A.A.); (A.S.F.); (E.Y.O.); (E.N.K.); (V.P.Z.)
- Laboratory of Lymphatic Research, Diagnosis and Therapy (LDT), University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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Change in CSF Dynamics Responsible for ICP Elevation After Ischemic Stroke in Rats: a New Mechanism for Unexplained END? Transl Stroke Res 2019; 11:310-318. [PMID: 31418164 DOI: 10.1007/s12975-019-00719-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 06/06/2019] [Accepted: 07/15/2019] [Indexed: 01/25/2023]
Abstract
It has been proposed that intracranial pressure (ICP) elevation and collateral failure are responsible for unexplained early neurological deterioration (END) in stroke. The study's aims were to investigate whether cerebral spinal fluid (CSF) dynamics, rather than edema, are responsible for elevation of ICP after ischemic stroke. Permanent middle cerebral artery occlusion (pMCAO) was induced with an intraluminal filament. At 24 h after stroke, baseline ICP was measured and CSF dynamics were probed via a steady-state infusion method. Diffusion-weighted imaging (DWI) and T2-weighted magnetic resonance imaging were performed to define cerebral ischemic damage and the volume of brain swelling. We found that the pMCAO group exhibited a significant increase in CSF outflow resistance (2.27 ± 0.15 mmHg μL-1 min) compared with the sham group (0.93 ± 0.06 mmHg μL-1 min, p = 0.002). There was no correlation between mean ICP at 24 h post-pMCAO and edema (r2 = - 0.03, p = 0.5) or infarct volumes (r2 = 0.09, p = 0.5). However, for the first time, we found a significant correlation between the baseline ICP at 24 h post-stroke and the value of CSF outflow resistance. Results show that CSF outflow resistance, rather than edema, was the mechanism responsible for ICP elevation following ischemic stroke. This challenges current concepts and suggests the possibility that intracranial hypertension may be occurring undetected in a much wider range of stroke patients than is currently considered to be the case. In addition, this further supports the hypothesis that unexplained early neurological deterioration is the result of elevated ICP, leading to reduced collateral flow and cerebral perfusion.
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Ateshian GA, Shim JJ, Maas SA, Weiss JA. Finite Element Framework for Computational Fluid Dynamics in FEBio. J Biomech Eng 2019; 140:2666594. [PMID: 29238817 DOI: 10.1115/1.4038716] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Indexed: 01/22/2023]
Abstract
The mechanics of biological fluids is an important topic in biomechanics, often requiring the use of computational tools to analyze problems with realistic geometries and material properties. This study describes the formulation and implementation of a finite element framework for computational fluid dynamics (CFD) in FEBio, a free software designed to meet the computational needs of the biomechanics and biophysics communities. This formulation models nearly incompressible flow with a compressible isothermal formulation that uses a physically realistic value for the fluid bulk modulus. It employs fluid velocity and dilatation as essential variables: The virtual work integral enforces the balance of linear momentum and the kinematic constraint between fluid velocity and dilatation, while fluid density varies with dilatation as prescribed by the axiom of mass balance. Using this approach, equal-order interpolations may be used for both essential variables over each element, contrary to traditional mixed formulations that must explicitly satisfy the inf-sup condition. The formulation accommodates Newtonian and non-Newtonian viscous responses as well as inviscid fluids. The efficiency of numerical solutions is enhanced using Broyden's quasi-Newton method. The results of finite element simulations were verified using well-documented benchmark problems as well as comparisons with other free and commercial codes. These analyses demonstrated that the novel formulation introduced in FEBio could successfully reproduce the results of other codes. The analogy between this CFD formulation and standard finite element formulations for solid mechanics makes it suitable for future extension to fluid-structure interactions (FSIs).
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Affiliation(s)
- Gerard A Ateshian
- Department of Mechanical Engineering, Columbia University, New York, NY 10027
| | - Jay J Shim
- Department of Mechanical Engineering, Columbia University, New York, NY 10027
| | - Steve A Maas
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112
| | - Jeffrey A Weiss
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112
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Safety and feasibility of lumbar drainage in the management of poor grade aneurysmal subarachnoid hemorrhage. J Clin Neurosci 2019; 64:64-70. [DOI: 10.1016/j.jocn.2019.04.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 02/20/2019] [Accepted: 04/12/2019] [Indexed: 11/23/2022]
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Altafulla J, Bordes S, Jenkins S, Litvack Z, Iwanaga J, Loukas M, Tubbs RS. The Basal Subarachnoid Cisterns: Surgical and Anatomical Considerations. World Neurosurg 2019; 129:190-199. [PMID: 31136838 DOI: 10.1016/j.wneu.2019.05.087] [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: 02/27/2019] [Revised: 05/09/2019] [Accepted: 05/10/2019] [Indexed: 10/26/2022]
Abstract
The basal subarachnoid cisterns are expansions of the subarachnoid space and transmit cranial nerves and intracranial vessels. Providing neurosurgeons with key concepts, anatomical landmarks, and techniques can result in safer procedures and better patient outcomes. In this review, we discuss the major basal subarachnoid cisterns including their embryology, history, anatomical descriptions, and use during surgical approaches.
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Affiliation(s)
- Juan Altafulla
- Seattle Science Foundation, Seattle, Washington, USA; Swedish Neuroscience Institute, Swedish Medical Center, Seattle, Washington, USA
| | - Stephen Bordes
- Department of Anatomical Sciences, St. George's University, St. George's, Grenada
| | - Skyler Jenkins
- Department of Anatomical Sciences, St. George's University, St. George's, Grenada
| | - Zachary Litvack
- Swedish Neuroscience Institute, Swedish Medical Center, Seattle, Washington, USA
| | - Joe Iwanaga
- Seattle Science Foundation, Seattle, Washington, USA.
| | - Marios Loukas
- Department of Anatomical Sciences, St. George's University, St. George's, Grenada
| | - R Shane Tubbs
- Seattle Science Foundation, Seattle, Washington, USA; Department of Anatomical Sciences, St. George's University, St. George's, Grenada
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MATSUMAE M, KURODA K, YATSUSHIRO S, HIRAYAMA A, HAYASHI N, TAKIZAWA K, ATSUMI H, SORIMACHI T. Changing the Currently Held Concept of Cerebrospinal Fluid Dynamics Based on Shared Findings of Cerebrospinal Fluid Motion in the Cranial Cavity Using Various Types of Magnetic Resonance Imaging Techniques. Neurol Med Chir (Tokyo) 2019; 59:133-146. [PMID: 30814424 PMCID: PMC6465527 DOI: 10.2176/nmc.ra.2018-0272] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 01/10/2019] [Indexed: 12/23/2022] Open
Abstract
The "cerebrospinal fluid (CSF) circulation theory" of CSF flowing unidirectionally and circulating through the ventricles and subarachnoid space in a downward or upward fashion has been widely recognized. In this review, observations of CSF motion using different magnetic resonance imaging (MRI) techniques are described, findings that are shared among these techniques are extracted, and CSF motion, as we currently understand it based on the results from the quantitative analysis of CSF motion, is discussed, along with a discussion of slower water molecule motion in the perivascular, paravascular, and brain parenchyma. Today, a shared consensus regarding CSF motion is being formed, as follows: CSF motion is not a circulatory flow, but a combination of various directions of flow in the ventricles and subarachnoid space, and the acceleration of CSF motion differs depending on the CSF space. It is now necessary to revise the currently held concept that CSF flows unidirectionally. Currently, water molecule motion in the order of centimeters per second can be detected with various MRI techniques. Thus, we need new MRI techniques with high-velocity sensitivity, such as in the order of 10 μm/s, to determine water molecule movement in the vessel wall, paravascular space, and brain parenchyma. In this paper, the authors review the previous and current concepts of CSF motion in the central nervous system using various MRI techniques.
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Affiliation(s)
- Mitsunori MATSUMAE
- Department of Neurosurgery, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Kagayaki KURODA
- Department of Human and Information Sciences, School of Information Science and Technology, Tokai University, Hiratsuka, Kanagawa, Japan
| | - Satoshi YATSUSHIRO
- Department of Human and Information Sciences, School of Information Science and Technology, Tokai University, Hiratsuka, Kanagawa, Japan
- BioView Inc., Tokyo, Japan
| | - Akihiro HIRAYAMA
- Department of Neurosurgery, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Naokazu HAYASHI
- Department of Neurosurgery, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Ken TAKIZAWA
- Department of Ophthalmology, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Hideki ATSUMI
- Department of Neurosurgery, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Takatoshi SORIMACHI
- Department of Neurosurgery, Tokai University School of Medicine, Isehara, Kanagawa, Japan
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Apura J, Tiago J, Bugalho de Moura A, Lourenço JA, Sequeira A. The effect of ventricular volume increase in the amplitude of intracranial pressure. Comput Methods Biomech Biomed Engin 2019; 22:889-900. [PMID: 30931613 DOI: 10.1080/10255842.2019.1587413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We study the impact of vascular pulse in the cerebrospinal fluid (CSF) pressure measured on the lateral cerebral ventricles, as well as its sensitivity with respect to ventricular volume change. Recent studies have addressed the importance of the compliance capacity in the brain and its relation to arterial pulse abortion in communicating hydrocephalus. Nevertheless, this mechanism is not fully understood. We propose a fluid-structure interaction (FSI) model on a 3 D idealized geometry based on realistic physiological and morphological parameters. The computational model describes the pulsatile deformation of the third ventricle due to arterial pulse and the resulting CSF dynamics inside brain pathways. The results show that when the volume of lateral ventricles increases up to 3.5 times, the amplitudes of both average and maximum pressure values, computed on the lateral ventricles surface, substantially decrease. This indicates that the lateral ventricles expansion leads to a dumping effect on the pressure exerted on the walls of the ventricles. These results strengthen the possibility that communicant hydrocephalus may, in fact, be a natural response to reduce abnormal high intracranial pressure (ICP) amplitude. This conclusion is in accordance with recent hypotheses suggesting that communicant hydrocephalus is related to a disequilibrium in brain compliance capacity.
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Affiliation(s)
- João Apura
- a Center for Computational and Stochastic Mathematics - CEMAT , Lisboa , Portugal
| | - Jorge Tiago
- a Center for Computational and Stochastic Mathematics - CEMAT , Lisboa , Portugal
| | - Alexandra Bugalho de Moura
- b Department of Mathematics and REM - CEMAPRE , ISEG - Lisbon School of Economics and Management, Universidade de Lisboa , Lisboa , Portugal
| | - José Artur Lourenço
- c Neurosurgery Department , Centro Hospitalar Universitrio do Algarve , Faro , Portugal
| | - Adélia Sequeira
- d Center for Computational and Stochastic Mathematics - CEMAT, Department of Mathematics, Instituto Superior Técnico , University of Lisbon , Lisboa , Portugal
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Shim JJ, Maas SA, Weiss JA, Ateshian GA. A Formulation for Fluid Structure-Interactions in FEBio Using Mixture Theory. J Biomech Eng 2019; 141:2727817. [PMID: 30835271 DOI: 10.1115/1.4043031] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Indexed: 11/08/2022]
Abstract
Many physiological systems involve strong interactions between fluids and solids, posing a signicant challenge when modeling biomechanics. The objective of this study was to implement a fluid-structure interaction (FSI) solver in the free, open-source finite element code FEBio (febio.org), that combined the existing solid mechanics and rigid body dynamics solver with a recently-developed computational fluid dynamics (CFD) solver. A novel Galerkin-based finite element FSI formulation was introduced based on mixture theory, where the FSI domain was described as a mixture of fluid and solid constituents that have distinct motions. The mesh was defined on the solid domain, specialized to have zero mass, negligible stiffness and zero frictional interactions with the fluid, whereas the fluid was modeled as isothermal and compressible. The mixture framework provided the foundation for evaluating material time derivatives in a material frame for the solid and in a spatial frame for the fluid. Similar to our recently reported CFD solver, our FSI formulation did not require stabilization methods to achieve good convergence, producing a compact set of equations and code implementation. The code was successfully verified against benchmark problems and an analytical solution for squeeze-film lubrication. It was validated against experimental measurements of the flow rate in a peristaltic pump, and illustrated using non-Newtonian blood flow through a bifurcated carotid artery with a thick arterial wall. The successful formulation and implementation of this FSI solver enhances the multiphysics modeling capabilities in FEBio relevant to the biomechanics and biophysics communities.
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Affiliation(s)
- Jay J Shim
- Department of Mechanical Engineering, Columbia University, New York, NY 10027
| | - Steve A Maas
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112
| | - Jeffrey A Weiss
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112
| | - Gerard A Ateshian
- Department of Mechanical Engineering, Columbia University, New York, NY 10027
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Bartoň M, Mareček R, Krajčovičová L, Slavíček T, Kašpárek T, Zemánková P, Říha P, Mikl M. Evaluation of different cerebrospinal fluid and white matter fMRI filtering strategies-Quantifying noise removal and neural signal preservation. Hum Brain Mapp 2019; 40:1114-1138. [PMID: 30403309 PMCID: PMC6865642 DOI: 10.1002/hbm.24433] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 08/17/2018] [Accepted: 10/08/2018] [Indexed: 12/16/2022] Open
Abstract
This study examines the impact of using different cerebrospinal fluid (CSF) and white matter (WM) nuisance signals for data-driven filtering of functional magnetic resonance imaging (fMRI) data as a cleanup method before analyzing intrinsic brain fluctuations. The routinely used temporal signal-to-noise ratio metric is inappropriate for assessing fMRI filtering suitability, as it evaluates only the reduction of data variability and does not assess the preservation of signals of interest. We defined a new metric that evaluates the preservation of selected neural signal correlates, and we compared its performance with a recently published signal-noise separation metric. These two methods provided converging evidence of the unfavorable impact of commonly used filtering approaches that exploit higher numbers of principal components from CSF and WM compartments (typically 5 + 5 for CSF and WM, respectively). When using only the principal components as nuisance signals, using a lower number of signals results in a better performance (i.e., 1 + 1 performed best). However, there was evidence that this routinely used approach consisting of 1 + 1 principal components may not be optimal for filtering resting-state (RS) fMRI data, especially when RETROICOR filtering is applied during the data preprocessing. The evaluation of task data indicated the appropriateness of 1 + 1 principal components, but when RETROICOR was applied, there was a change in the optimal filtering strategy. The suggested change for extracting WM (and also CSF in RETROICOR-corrected RS data) is using local signals instead of extracting signals from a large mask using principal component analysis.
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Affiliation(s)
- Marek Bartoň
- CEITEC – Central European Institute of Technology, Masaryk UniversityBrnoCzech Republic
- First Department of NeurologyFaculty of Medicine of the Masaryk University and St. Anne's University HospitalBrnoCzech Republic
| | - Radek Mareček
- CEITEC – Central European Institute of Technology, Masaryk UniversityBrnoCzech Republic
| | - Lenka Krajčovičová
- CEITEC – Central European Institute of Technology, Masaryk UniversityBrnoCzech Republic
| | - Tomáš Slavíček
- CEITEC – Central European Institute of Technology, Masaryk UniversityBrnoCzech Republic
| | - Tomáš Kašpárek
- Department of PsychiatryUniversity Hospital Brno and Faculty of Medicine, Masaryk UniversityBrnoCzech Republic
| | - Petra Zemánková
- CEITEC – Central European Institute of Technology, Masaryk UniversityBrnoCzech Republic
- First Department of NeurologyFaculty of Medicine of the Masaryk University and St. Anne's University HospitalBrnoCzech Republic
- Department of PsychiatryUniversity Hospital Brno and Faculty of Medicine, Masaryk UniversityBrnoCzech Republic
| | - Pavel Říha
- CEITEC – Central European Institute of Technology, Masaryk UniversityBrnoCzech Republic
| | - Michal Mikl
- CEITEC – Central European Institute of Technology, Masaryk UniversityBrnoCzech Republic
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Khani M, Lawrence BJ, Sass LR, Gibbs CP, Pluid JJ, Oshinski JN, Stewart GR, Zeller JR, Martin BA. Characterization of intrathecal cerebrospinal fluid geometry and dynamics in cynomolgus monkeys (macaca fascicularis) by magnetic resonance imaging. PLoS One 2019; 14:e0212239. [PMID: 30811449 PMCID: PMC6392269 DOI: 10.1371/journal.pone.0212239] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 01/29/2019] [Indexed: 02/08/2023] Open
Abstract
Recent advancements have been made toward understanding the diagnostic and therapeutic potential of cerebrospinal fluid (CSF) and related hydrodynamics. Increased understanding of CSF dynamics may lead to improved detection of central nervous system (CNS) diseases and optimized delivery of CSF based CNS therapeutics, with many proposed therapeutics hoping to successfully treat or cure debilitating neurological conditions. Before significant strides can be made toward the research and development of interventions designed for human use, additional research must be carried out with representative subjects such as non-human primates (NHP). This study presents a geometric and hydrodynamic characterization of CSF in eight cynomolgus monkeys (Macaca fascicularis) at baseline and two-week follow-up. Results showed that CSF flow along the entire spine was laminar with a Reynolds number ranging up to 80 and average Womersley number ranging from 4.1–7.7. Maximum CSF flow rate occurred ~25 mm caudal to the foramen magnum. Peak CSF flow rate ranged from 0.3–0.6 ml/s at the C3-C4 level. Geometric analysis indicated that average intrathecal CSF volume below the foramen magnum was 7.4 ml. The average surface area of the spinal cord and dura was 44.7 and 66.7 cm2 respectively. Subarachnoid space cross-sectional area and hydraulic diameter ranged from 7–75 mm2 and 2–3.7 mm, respectively. Stroke volume had the greatest value of 0.14 ml at an axial location corresponding to C3-C4.
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Affiliation(s)
- Mohammadreza Khani
- Department of Biological Engineering, University of Idaho, Moscow, ID, United States of America
| | - Braden J. Lawrence
- Department of Biological Engineering, University of Idaho, Moscow, ID, United States of America
- School of Medicine, University of Washington, Seattle, WA, United States of America
| | - Lucas R. Sass
- Department of Biological Engineering, University of Idaho, Moscow, ID, United States of America
| | - Christina P. Gibbs
- Department of Biological Engineering, University of Idaho, Moscow, ID, United States of America
| | - Joshua J. Pluid
- Department of Biological Engineering, University of Idaho, Moscow, ID, United States of America
| | - John N. Oshinski
- Department of Radiology, Emory University, Atlanta, GA, United States of America
| | - Gregory R. Stewart
- Axovant, New York, NY, United States of America
- Voyager Therapeutics, Cambridge, MA, United States of America
| | | | - Bryn A. Martin
- Department of Biological Engineering, University of Idaho, Moscow, ID, United States of America
- * E-mail:
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Toro EF, Thornber B, Zhang Q, Scoz A, Contarino C. A Computational Model for the Dynamics of Cerebrospinal Fluid in the Spinal Subarachnoid Space. J Biomech Eng 2018; 141:2705150. [DOI: 10.1115/1.4041551] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Indexed: 11/08/2022]
Abstract
Global models for the dynamics of coupled fluid compartments of the central nervous system (CNS) require simplified representations of the individual components which are both accurate and computationally efficient. This paper presents a one-dimensional model for computing the flow of cerebrospinal fluid (CSF) within the spinal subarachnoid space (SSAS) under the simplifying assumption that it consists of two coaxial tubes representing the spinal cord and the dura. A rigorous analysis of the first-order nonlinear system demonstrates that the system is elliptic-hyperbolic, and hence ill-posed, for some values of parameters, being hyperbolic otherwise. In addition, the system cannot be written in conservation-law form, and thus, an appropriate numerical approach is required, namely the path conservative approach. The designed computational algorithm is shown to be second-order accurate in both space and time, capable of handling strongly nonlinear discontinuities, and a method of coupling it with an unsteady inflow condition is presented. Such an approach is sufficiently rapid to be integrated into a global, closed-loop model for computing the dynamics of coupled fluid compartments of the CNS.
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Affiliation(s)
- Eleuterio F. Toro
- Laboratory of Applied Mathematics, University of Trento, via Mesiano 77, Mesiano, Trento 38123, Italy
| | - Ben Thornber
- School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, Sydney 2006, Australia e-mail:
| | - Qinghui Zhang
- Laboratory of Applied Mathematics, University of Trento, via Mesiano 77, Mesiano, Trento 38123, Italy
| | - Alessia Scoz
- Department of Mathematics, University of Trento, via Sommarive 14, Povo, Trento 38123, Italy
| | - Christian Contarino
- Department of Mathematics, University of Trento, via Sommarive 14, Povo, Trento 38123, Italy
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40
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Abbott NJ, Pizzo ME, Preston JE, Janigro D, Thorne RG. The role of brain barriers in fluid movement in the CNS: is there a 'glymphatic' system? Acta Neuropathol 2018; 135:387-407. [PMID: 29428972 DOI: 10.1007/s00401-018-1812-4] [Citation(s) in RCA: 341] [Impact Index Per Article: 56.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/16/2018] [Accepted: 01/24/2018] [Indexed: 12/15/2022]
Abstract
Brain fluids are rigidly regulated to provide stable environments for neuronal function, e.g., low K+, Ca2+, and protein to optimise signalling and minimise neurotoxicity. At the same time, neuronal and astroglial waste must be promptly removed. The interstitial fluid (ISF) of the brain tissue and the cerebrospinal fluid (CSF) bathing the CNS are integral to this homeostasis and the idea of a glia-lymph or 'glymphatic' system for waste clearance from brain has developed over the last 5 years. This links bulk (convective) flow of CSF into brain along the outside of penetrating arteries, glia-mediated convective transport of fluid and solutes through the brain extracellular space (ECS) involving the aquaporin-4 (AQP4) water channel, and finally delivery of fluid to venules for clearance along peri-venous spaces. However, recent evidence favours important amendments to the 'glymphatic' hypothesis, particularly concerning the role of glia and transfer of solutes within the ECS. This review discusses studies which question the role of AQP4 in ISF flow and the lack of evidence for its ability to transport solutes; summarizes attributes of brain ECS that strongly favour the diffusion of small and large molecules without ISF flow; discusses work on hydraulic conductivity and the nature of the extracellular matrix which may impede fluid movement; and reconsiders the roles of the perivascular space (PVS) in CSF-ISF exchange and drainage. We also consider the extent to which CSF-ISF exchange is possible and desirable, the impact of neuropathology on fluid drainage, and why using CSF as a proxy measure of brain components or drug delivery is problematic. We propose that new work and key historical studies both support the concept of a perivascular fluid system, whereby CSF enters the brain via PVS convective flow or dispersion along larger caliber arteries/arterioles, diffusion predominantly regulates CSF/ISF exchange at the level of the neurovascular unit associated with CNS microvessels, and, finally, a mixture of CSF/ISF/waste products is normally cleared along the PVS of venules/veins as well as other pathways; such a system may or may not constitute a true 'circulation', but, at the least, suggests a comprehensive re-evaluation of the previously proposed 'glymphatic' concepts in favour of a new system better taking into account basic cerebrovascular physiology and fluid transport considerations.
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Affiliation(s)
- N Joan Abbott
- Faculty of Life Sciences and Medicine, Institute of Pharmaceutical Science, King's College London, Franklin Wilkins Building 3.82, 150 Stamford St, London, SE1 9NH, UK.
| | - Michelle E Pizzo
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison School of Pharmacy, Madison, WI, USA
- Clinical Neuroengineering Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Jane E Preston
- Faculty of Life Sciences and Medicine, Institute of Pharmaceutical Science, King's College London, Franklin Wilkins Building 3.82, 150 Stamford St, London, SE1 9NH, UK
| | - Damir Janigro
- Flocel Inc., Cleveland, OH, USA
- Department of Physiology, Case Western Reserve University, Cleveland, OH, USA
| | - Robert G Thorne
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison School of Pharmacy, Madison, WI, USA.
- Clinical Neuroengineering Training Program, University of Wisconsin-Madison, Madison, WI, USA.
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, USA.
- Cellular and Molecular Pathology Graduate Training Program, University of Wisconsin-Madison, Madison, WI, USA.
- Institute for Clinical and Translational Research, University of Wisconsin-Madison, Madison, WI, USA.
- , 5113 Rennebohm Hall, 777 Highland Avenue, Madison, WI, 53705, USA.
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41
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Würzer B, Laza C, Pons-Kühnemann J, Kaps M, Junge B, Roessler FC. Speckle Tracking in Transcranial Ultrasound Allows Noninvasive Analysis of Pulsation Patterns of the Third Ventricle. ULTRASONIC IMAGING 2018; 40:127-138. [PMID: 29207924 DOI: 10.1177/0161734617745670] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Cerebrospinal fluid (CSF) flow is sensitive to many cerebral disorders. We aimed to develop a noninvasive bedside method to detect physiological and pathological CSF phenomena by measuring pulsation patterns of the third ventricle. By transcranial B-mode ultrasound, electrocardiography (ECG)-gated video loops of the third ventricle were acquired. "Speckle tracking" software was used to quantify the relative change of its width. We conducted measurements of nine cardiac cycles in 11 healthy subjects in sitting and in supine position during Valsalva maneuver to investigate the influence of an increased intracranial pressure on the relative deformation of the third ventricle. In one patient with occlusive hydrocephalus, 19 cardiac cycles were measured in sitting position before and after removal of a tumorous obstruction of the aqueduct of Sylvius. Healthy subjects expressed a pulse-related increased width of the third ventricle ([Formula: see text]: +5.69, 95% confidence interval [CI] = [4.38, 7.00]). No significant difference was found between the sitting and the supine position in healthy adults. In the preoperative state of occlusive hydrocephalus, we found a negative, pulse-related deformation ([Formula: see text]: -1.86, 95% CI = [-2.15, -1.58]) with delayed onset. After surgery, the deformation pattern resembled that of our healthy controls. The difference between pre- and postoperative condition was significant (p < 0.001). Transcranial B-mode sonography can be used to record small movements of the sidewalls of the third ventricle. This noninvasive bedside method is suitable to assess CSF pulsatility within the third ventricle and might be able to distinguish between physiological and pathological flows.
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Affiliation(s)
- Benjamin Würzer
- 1 Department of Neurology, Justus-Liebig University Giessen, Giessen, Germany
| | - Cristina Laza
- 2 Clinic of Neurology, County Clinical Emergency Hospital "Sfântul Apostol Andrei," Constanța, Romania
| | - Jörn Pons-Kühnemann
- 3 Medical Statistics, Institute of Medical Informatics, Justus-Liebig University Giessen, Giessen, Germany
| | - Manfred Kaps
- 1 Department of Neurology, Justus-Liebig University Giessen, Giessen, Germany
| | - Bernd Junge
- 1 Department of Neurology, Justus-Liebig University Giessen, Giessen, Germany
| | - Florian C Roessler
- 1 Department of Neurology, Justus-Liebig University Giessen, Giessen, Germany
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Khani M, Xing T, Gibbs C, Oshinski JN, Stewart GR, Zeller JR, Martin BA. Nonuniform Moving Boundary Method for Computational Fluid Dynamics Simulation of Intrathecal Cerebrospinal Flow Distribution in a Cynomolgus Monkey. J Biomech Eng 2018; 139:2625663. [PMID: 28462417 DOI: 10.1115/1.4036608] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Indexed: 11/08/2022]
Abstract
A detailed quantification and understanding of cerebrospinal fluid (CSF) dynamics may improve detection and treatment of central nervous system (CNS) diseases and help optimize CSF system-based delivery of CNS therapeutics. This study presents a computational fluid dynamics (CFD) model that utilizes a nonuniform moving boundary approach to accurately reproduce the nonuniform distribution of CSF flow along the spinal subarachnoid space (SAS) of a single cynomolgus monkey. A magnetic resonance imaging (MRI) protocol was developed and applied to quantify subject-specific CSF space geometry and flow and define the CFD domain and boundary conditions. An algorithm was implemented to reproduce the axial distribution of unsteady CSF flow by nonuniform deformation of the dura surface. Results showed that maximum difference between the MRI measurements and CFD simulation of CSF flow rates was <3.6%. CSF flow along the entire spine was laminar with a peak Reynolds number of ∼150 and average Womersley number of ∼5.4. Maximum CSF flow rate was present at the C4-C5 vertebral level. Deformation of the dura ranged up to a maximum of 134 μm. Geometric analysis indicated that total spinal CSF space volume was ∼8.7 ml. Average hydraulic diameter, wetted perimeter, and SAS area were 2.9 mm, 37.3 mm and 27.24 mm2, respectively. CSF pulse wave velocity (PWV) along the spine was quantified to be 1.2 m/s.
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Affiliation(s)
- Mohammadreza Khani
- Neurophysiological Imaging and Modeling Laboratory, Department of Biological Engineering, University of Idaho, Moscow, ID 83844 e-mail:
| | - Tao Xing
- Department of Mechanical Engineering, University of Idaho, Moscow, ID 83844 e-mail:
| | - Christina Gibbs
- Neurophysiological Imaging and Modeling Laboratory, Department of Biological Engineering, University of Idaho, Moscow, ID 83844 e-mail:
| | - John N Oshinski
- Department of Radiology, Emory University, Atlanta, GA 30322 e-mail:
| | | | | | - Bryn A Martin
- Neurophysiological Imaging and Modeling Laboratory, Department of Biological Engineering, University of Idaho, Moscow, ID 83844 e-mail:
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Barten DM, Cadelina GW, Weed MR. Dosing, collection, and quality control issues in cerebrospinal fluid research using animal models. HANDBOOK OF CLINICAL NEUROLOGY 2018; 146:47-64. [PMID: 29110779 DOI: 10.1016/b978-0-12-804279-3.00004-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Cerebrospinal fluid (CSF) is a complex fluid filling the ventricular system and surrounding the brain and spinal cord. Although the bulk of CSF is created by the choroid plexus, a significant fraction derives from the interstitial fluid in the brain and spinal cord parenchyma. For this reason, CSF can often be used as a source of pharmacodynamic and prognostic biomarkers to reflect biochemical changes occurring within the brain. For instance, CSF biomarkers can be used to diagnose and track progression of disease as well as understand pharmacokinetic and pharmacodynamic relationships in clinical trials. To facilitate the use of these biomarkers in humans, studies in preclinical species are often valuable. This review summarizes methods for preclinical CSF collection for biomarkers from mice, rats, and nonhuman primates. In addition, dosing directly into CSF is increasingly being used to improve drug levels in the brain. Therefore, this review also summarizes the state of the art in CSF dosing in these preclinical species.
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Affiliation(s)
- Donna M Barten
- Genetically Defined Diseases, Bristol-Myers Squibb, Wallingford, CT, United States
| | - Gregory W Cadelina
- Genetically Defined Diseases, Bristol-Myers Squibb, Wallingford, CT, United States
| | - Michael R Weed
- Genetically Defined Diseases, Bristol-Myers Squibb, Wallingford, CT, United States; RxGen, Inc, New Haven, CT, United States.
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44
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Cerebrospinal Fluid Dynamics and Intrathecal Delivery. Neuromodulation 2018. [DOI: 10.1016/b978-0-12-805353-9.00067-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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45
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Luc JGY, Pierre CA, Phan K, Vahedein YS, Liberson AS, Cornwell WK, Phillips SJ, Tchantchaleishvili V. Fluid structure interaction model analysis of cerebrospinal fluid circulation in patients with continuous-flow left ventricular assist devices. Int J Artif Organs 2017; 41:0. [PMID: 29148023 DOI: 10.5301/ijao.5000657] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/23/2017] [Indexed: 11/20/2022]
Abstract
PURPOSE The current 1-dimensional fluid structure interaction model (FSI) for understanding cerebrospinal fluid (CSF) circulation requires pulsatility as a precondition and has not been applied to patients with continuous-flow left ventricular assist devices (CF-LVAD) where pulsatility is chronically reduced. Our study aims to characterize the behavior of CSF pressure and flow in patients with CF-LVADs using a computational FSI model. METHODS Utilizing the computational FSI model, CSF production in choroid plexuses of the 4 ventricles was specified as a boundary condition for the model. The other source of production from capillary ultrafiltrate spaces was accounted for by the mass conservation equation. The primary CSF absorption sites (i.e., arachnoid granulations) were treated as the outlet boundary conditions. We established a low pulse wave to represent patients with a CF-LVAD. RESULTS From the model, low pulse conditions resulted in a reduction in CSF pressure amplitude and velocity though the overall flow rate was unchanged. CONCLUSIONS The existing FSI model is not a suitable representation of CSF flow in CF-LVAD patients. More studies are needed to elucidate the role of pulsatility in CSF flow and the compensatory changes in CSF production and absorption that occur in patients with CF-LVADs in whom pulsatility is diminished.
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Affiliation(s)
- Jessica G Y Luc
- Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB - Canada
| | - Clifford A Pierre
- Department of Neurosurgery, University of Rochester Medical Center, Rochester, NY - USA
| | - Kevin Phan
- Faculty of Medicine, University of Sydney, Sydney - Australia
| | - Yashar S Vahedein
- Kate Gleason College of Engineering, Rochester Institute of Technology, Rochester, NY - USA
| | - Alexander S Liberson
- Kate Gleason College of Engineering, Rochester Institute of Technology, Rochester, NY - USA
| | - William K Cornwell
- Division of Cardiology, Department of Internal Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO - USA
| | - Steven J Phillips
- National Library of Medicine, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, MD - USA
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Goffin C, Leonhardt S, Radermacher K. The Role of a Dynamic Craniospinal Compliance in NPH—A Review and Future Challenges. IEEE Rev Biomed Eng 2017; 10:310-322. [DOI: 10.1109/rbme.2016.2620493] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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47
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Tangen K, Narasimhan NS, Sierzega K, Preden T, Alaraj A, Linninger AA. Clearance of Subarachnoid Hemorrhage from the Cerebrospinal Fluid in Computational and In Vitro Models. Ann Biomed Eng 2016; 44:3478-3494. [DOI: 10.1007/s10439-016-1681-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 06/18/2016] [Indexed: 12/30/2022]
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48
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Bianciardi M, Toschi N, Polimeni JR, Evans KC, Bhat H, Keil B, Rosen BR, Boas DA, Wald LL. The pulsatility volume index: an indicator of cerebrovascular compliance based on fast magnetic resonance imaging of cardiac and respiratory pulsatility. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2016; 374:20150184. [PMID: 27044992 PMCID: PMC4822444 DOI: 10.1098/rsta.2015.0184] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/26/2015] [Indexed: 05/03/2023]
Abstract
The influence of cardiac activity on the viscoelastic properties of intracranial tissue is one of the mechanisms through which brain-heart interactions take place, and is implicated in cerebrovascular disease. Cerebrovascular disease risk is not fully explained by current risk factors, including arterial compliance. Cerebrovascular compliance is currently estimated indirectly through Doppler sonography and magnetic resonance imaging (MRI) measures of blood velocity changes. In order to meet the need for novel cerebrovascular disease risk factors, we aimed to design and validate an MRI indicator of cerebrovascular compliance based on direct endogenous measures of blood volume changes. We implemented a fast non-gated two-dimensional MRI pulse sequence based on echo-planar imaging (EPI) with ultra-short repetition time (approx. 30-50 ms), which stepped through slices every approximately 20 s. We constrained the solution of the Bloch equations for spins moving faster than a critical speed to produce an endogenous contrast primarily dependent on spin volume changes, and an approximately sixfold signal gain compared with Ernst angle acquisitions achieved by the use of a 90° flip angle. Using cardiac and respiratory peaks detected on physiological recordings, average cardiac and respiratory MRI pulse waveforms in several brain compartments were obtained at 7 Tesla, and used to derive a compliance indicator, the pulsatility volume index (pVI). The pVI, evaluated in larger cerebral arteries, displayed significant variation within and across vessels. Multi-echo EPI showed the presence of significant pulsatility effects in both S0 and [Formula: see text] signals, compatible with blood volume changes. Lastly, the pVI dynamically varied during breath-holding compared with normal breathing, as expected for a compliance indicator. In summary, we characterized and performed an initial validation of a novel MRI indicator of cerebrovascular compliance, which might prove useful to investigate brain-heart interactions in cerebrovascular disease and other disorders.
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Affiliation(s)
- Marta Bianciardi
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Building 149, 13th Street, Charlestown, Boston, MA 02129, USA
| | - Nicola Toschi
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Building 149, 13th Street, Charlestown, Boston, MA 02129, USA Medical Physics Section, Department of Biomedicine and Prevention, Faculty of Medicine, University of Rome 'Tor Vergata', Via Montpellier 1, 00133 Rome, Italy
| | - Jonathan R Polimeni
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Building 149, 13th Street, Charlestown, Boston, MA 02129, USA
| | - Karleyton C Evans
- Department of Psychiatry, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Building 149, 13th Street, Charlestown, Boston, MA 02129, USA
| | - Himanshu Bhat
- Siemens Healthcare, Building 149, 13th Street, Charlestown, Boston, MA 02129, USA
| | - Boris Keil
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Building 149, 13th Street, Charlestown, Boston, MA 02129, USA Institute for Medical Physics and Radiation Protection, Life Science Engineering, Mittelhessen University of Applied Science, Wiesenstrasse 14, 35390 Giessen, Germany
| | - Bruce R Rosen
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Building 149, 13th Street, Charlestown, Boston, MA 02129, USA
| | - David A Boas
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Building 149, 13th Street, Charlestown, Boston, MA 02129, USA
| | - Lawrence L Wald
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Building 149, 13th Street, Charlestown, Boston, MA 02129, USA
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49
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Martin BA, Yiallourou TI, Pahlavian SH, Thyagaraj S, Bunck AC, Loth F, Sheffer DB, Kröger JR, Stergiopulos N. Inter-operator Reliability of Magnetic Resonance Image-Based Computational Fluid Dynamics Prediction of Cerebrospinal Fluid Motion in the Cervical Spine. Ann Biomed Eng 2015; 44:1524-37. [PMID: 26446009 DOI: 10.1007/s10439-015-1449-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 09/03/2015] [Indexed: 11/30/2022]
Abstract
For the first time, inter-operator dependence of MRI based computational fluid dynamics (CFD) modeling of cerebrospinal fluid (CSF) in the cervical spinal subarachnoid space (SSS) is evaluated. In vivo MRI flow measurements and anatomy MRI images were obtained at the cervico-medullary junction of a healthy subject and a Chiari I malformation patient. 3D anatomies of the SSS were reconstructed by manual segmentation by four independent operators for both cases. CFD results were compared at nine axial locations along the SSS in terms of hydrodynamic and geometric parameters. Intraclass correlation (ICC) assessed the inter-operator agreement for each parameter over the axial locations and coefficient of variance (CV) compared the percentage of variance for each parameter between the operators. Greater operator dependence was found for the patient (0.19 < ICC < 0.99) near the craniovertebral junction compared to the healthy subject (ICC > 0.78). For the healthy subject, hydraulic diameter and Womersley number had the least variance (CV = ~2%). For the patient, peak diastolic velocity and Reynolds number had the smallest variance (CV = ~3%). These results show a high degree of inter-operator reliability for MRI-based CFD simulations of CSF flow in the cervical spine for healthy subjects and a lower degree of reliability for patients with Type I Chiari malformation.
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Affiliation(s)
- Bryn A Martin
- Neurophysiological Imaging and Modeling Laboratory, Department of Biological Engineering, The University of Idaho, 875 Perimeter Drive MS 0904, Moscow, ID, 83844-0904, USA.
| | - Theresia I Yiallourou
- Laboratory of Hemodynamics and Cardiovascular Technology, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Soroush Heidari Pahlavian
- Department of Mechanical Engineering, Conquer Chiari Research Center, The University of Akron, Akron, OH, USA
| | - Suraj Thyagaraj
- Department of Mechanical Engineering, Conquer Chiari Research Center, The University of Akron, Akron, OH, USA
| | - Alexander C Bunck
- Department of Radiology, University Hospital of Cologne, Cologne, Germany.,Department of Clinical Radiology, University of Muenster, Münster, Germany
| | - Francis Loth
- Department of Mechanical Engineering, Conquer Chiari Research Center, The University of Akron, Akron, OH, USA
| | - Daniel B Sheffer
- Department of Biomedical Engineering, The University of Akron, Akron, OH, USA
| | - Jan Robert Kröger
- Department of Radiology, University Hospital of Cologne, Cologne, Germany.,Department of Clinical Radiology, University of Muenster, Münster, Germany
| | - Nikolaos Stergiopulos
- Laboratory of Hemodynamics and Cardiovascular Technology, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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50
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A Review of Computational Methods to Predict the Risk of Rupture of Abdominal Aortic Aneurysms. BIOMED RESEARCH INTERNATIONAL 2015; 2015:861627. [PMID: 26509168 PMCID: PMC4609803 DOI: 10.1155/2015/861627] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 05/26/2015] [Indexed: 12/02/2022]
Abstract
Computational methods have played an important role in health care in recent years, as determining parameters that affect a certain medical condition is not possible in experimental conditions in many cases. Computational fluid dynamics (CFD) methods have been used to accurately determine the nature of blood flow in the cardiovascular and nervous systems and air flow in the respiratory system, thereby giving the surgeon a diagnostic tool to plan treatment accordingly. Machine learning or data mining (MLD) methods are currently used to develop models that learn from retrospective data to make a prediction regarding factors affecting the progression of a disease. These models have also been successful in incorporating factors such as patient history and occupation. MLD models can be used as a predictive tool to determine rupture potential in patients with abdominal aortic aneurysms (AAA) along with CFD-based prediction of parameters like wall shear stress and pressure distributions. A combination of these computer methods can be pivotal in bridging the gap between translational and outcomes research in medicine. This paper reviews the use of computational methods in the diagnosis and treatment of AAA.
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