scholarly journals Anthropomorphic Model of Intrathecal Cerebrospinal Fluid Dynamics Within the Spinal Subarachnoid Space: Spinal Cord Nerve Roots Increase Steady-Streaming

2018 ◽  
Vol 140 (8) ◽  
Author(s):  
Mohammadreza Khani ◽  
Lucas R. Sass ◽  
Tao Xing ◽  
M. Keith Sharp ◽  
Olivier Balédent ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Spinal Cord ◽  
Cerebrospinal Fluid ◽  
Cfd Model ◽  
Csf Flow ◽  
Nerve Roots ◽  
Csf Dynamics ◽  
Steady Streaming ◽  
Spinal Subarachnoid Space ◽  
The Impact

Cerebrospinal fluid (CSF) dynamics are thought to play a vital role in central nervous system (CNS) physiology. The objective of this study was to investigate the impact of spinal cord (SC) nerve roots (NR) on CSF dynamics. A subject-specific computational fluid dynamics (CFD) model of the complete spinal subarachnoid space (SSS) with and without anatomically realistic NR and nonuniform moving dura wall deformation was constructed. This CFD model allowed detailed investigation of the impact of NR on CSF velocities that is not possible in vivo using magnetic resonance imaging (MRI) or other noninvasive imaging methods. Results showed that NR altered CSF dynamics in terms of velocity field, steady-streaming, and vortical structures. Vortices occurred in the cervical spine around NR during CSF flow reversal. The magnitude of steady-streaming CSF flow increased with NR, in particular within the cervical spine. This increase was located axially upstream and downstream of NR due to the interface of adjacent vortices that formed around NR.

scholarly journals In vitro and Numerical Simulation of Blood Removal from Cerebrospinal Fluid: Comparison of Lumbar Drain to Neurapheresis Therapy

2020 ◽  
Author(s):  
Mohammadreza Khani ◽  
Lucas Sass ◽  
M. Keith Sharp ◽  
Aaron McCabe ◽  
Laura Zitella Verbick ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Subarachnoid Space ◽  
Cfd Model ◽  
Tracer Concentration ◽  
Steady Streaming ◽  
Lumbar Drain ◽  
Spinal Subarachnoid Space ◽  
Subject Specific ◽  
The Impact

Abstract Background: Blood removal from cerebrospinal fluid (CSF) in post-subarachnoid hemorrhage patients may reduce the risk of related secondary brain injury. We formulated a computational fluid dynamics (CFD) model to investigate the impact of a dual-lumen catheter-based CSF filtration system, called Neurapheresis TM therapy, on blood removal from CSF compared to lumbar drain. Methods: A subject-specific multiphase CFD model of CSF system-wide solute transport was constructed based on MRI measurements. The Neurapheresis catheter geometry was added to the model within the spinal subarachnoid space. Neurapheresis flow aspiration and return rate was 2.0 and 1.8 (mL/min), versus 0.2 (mL/min) drainage for lumbar drain. Blood was modeled as a bulk fluid phase within CSF with a 10% initial tracer concentration and identical viscosity and density as CSF. Subject-specific oscillatory CSF flow was applied at the model inlet. The dura and spinal cord geometry were considered to be stationary. Spatial-temporal tracer concentration was quantified based on time-average steady-streaming velocities throughout the domain under Neurapheresis therapy and lumbar drain. To help verify CFD results, an optically clear in vitro CSF model was constructed with fluorescein used as a blood surrogate. Quantitative comparison of numerical and in vitro results was performed by linear regression of spatial-temporal tracer concentration over 24-hours. Results: After 24-hours, tracer concentration was reduced to 4.9% under Neurapheresis therapy compared to 6.5% under lumbar drain. Tracer clearance was most rapid between the catheter aspiration and return ports. Neurapheresis therapy was found to have a greater impact on steady-streaming compared to lumbar drain. Steady-streaming in the cranial SAS was ~50X smaller than in the spinal subarachnoid space for both cases. CFD results were strongly correlated with the in vitro spatial-temporal tracer concentration under Neurapheresis therapy (R 2 =0.89 with +2.13% and -1.93% tracer concentration confidence interval). Conclusion: A subject-specific CFD model of CSF system-wide solute transport was used to investigate the impact of Neurapheresis therapy on tracer removal from CSF compared to lumbar drain over a 24-hour period. Neurapheresis therapy was found to substantially increase tracer clearance compared to lumbar drain. The multiphase CFD results were verified by in vitro fluorescein tracer experiments.

scholarly journals In vitro and Numerical Simulation of Blood Removal from Cerebrospinal Fluid: Comparison of Lumbar Drain to Neurapheresis Therapy

2020 ◽  
Author(s):  
Mohammadreza Khani ◽  
Lucas Sass ◽  
M. Keith Sharp ◽  
Aaron McCabe ◽  
Laura Zitella Verbick ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Subarachnoid Space ◽  
Cfd Model ◽  
Tracer Concentration ◽  
Steady Streaming ◽  
Lumbar Drain ◽  
Spinal Subarachnoid Space ◽  
Subject Specific ◽  
The Impact

Abstract Background: Blood removal from cerebrospinal fluid (CSF) in post-subarachnoid hemorrhage patients may reduce the risk of related secondary brain injury. We formulated a computational fluid dynamics (CFD) model to investigate the impact of a dual-lumen catheter-based CSF filtration system, called Neurapheresis TM therapy, on blood removal from CSF compared to lumbar drain. Methods: A subject-specific multiphase CFD model of CSF system-wide solute transport was constructed based on MRI measurements. The Neurapheresis catheter geometry was added to the model within the spinal subarachnoid space. Neurapheresis flow aspiration and return rate was 2.0 and 1.8 (mL/min), versus 0.2 (mL/min) drainage for lumbar drain. Blood was modeled as a bulk fluid phase within CSF with a 10% initial tracer concentration and identical viscosity and density as CSF. Subject-specific oscillatory CSF flow was applied at the model inlet. The dura and spinal cord geometry were considered to be stationary. Spatial-temporal tracer concentration was quantified based on time-average steady-streaming velocities throughout the domain under Neurapheresis therapy and lumbar drain. To help verify CFD results, an optically clear in vitro CSF model was constructed with fluorescein used as a blood surrogate. Quantitative comparison of numerical and in vitro results was performed by linear regression of spatial-temporal tracer concentration over 24-hours. Results: After 24-hours, tracer concentration was reduced to 4.9% under Neurapheresis therapy compared to 6.5% under lumbar drain. Tracer clearance was most rapid between the catheter aspiration and return ports. Neurapheresis therapy was found to have a greater impact on steady-streaming compared to lumbar drain. Steady-streaming in the cranial SAS was ~50X smaller than in the spinal subarachnoid space for both cases. CFD results were strongly correlated with the in vitro spatial-temporal tracer concentration under Neurapheresis therapy (R 2 =0.89 with +2.13% and -1.93% tracer concentration confidence interval). Conclusion: A subject-specific CFD model of CSF system-wide solute transport was used to investigate the impact of Neurapheresis therapy on tracer removal from CSF compared to lumbar drain over a 24-hour period. Neurapheresis therapy was found to substantially increase tracer clearance compared to lumbar drain. The multiphase CFD results were verified by in vitro fluorescein tracer experiments.

Cerebrospinal Fluid Dynamics in the Cervical Spine: Importance of Fine Anatomical Structures

2013 ◽  
Author(s):  
S. H. Pahlavian ◽  
T. I. Yiallourou ◽  
R. S. Tubbs ◽  
A. Bunck ◽  
M. Goodin ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Cerebrospinal Fluid ◽  
Cervical Spine ◽  
Cfd Simulations ◽  
Nerve Roots ◽  
Csf Dynamics ◽  
Anatomical Structures ◽  
Spinal Subarachnoid Space ◽  
Computational Fluid Dynamics Cfd ◽  
Fine Structures

Fine anatomical structures, including nerve roots and denticulate ligaments, can significantly influence cerebrospinal fluid (CSF) dynamics inside the spinal subarachnoid space (SSS). In this study, we completed computational fluid dynamics (CFD) simulations based on subject specific geometries of the cervical spine with and without idealized fine structures (nerve roots and denticulate ligaments, NRDL). The results show that NRDL had a significant impact on CSF dynamics in terms of velocity distribution, flow streamlines, bidirectional nature of the flow and the pressure drop.

scholarly journals The Impact of Spinal Cord Nerve Roots and Denticulate Ligaments on Cerebrospinal Fluid Dynamics in the Cervical Spine

PLoS ONE ◽  
2014 ◽  
Vol 9 (4) ◽  
pp. e91888 ◽  
Author(s):  
Soroush Heidari Pahlavian ◽  
Theresia Yiallourou ◽  
R. Shane Tubbs ◽  
Alexander C. Bunck ◽  
Francis Loth ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Spinal Cord ◽  
Cerebrospinal Fluid ◽  
Cervical Spine ◽  
Cerebrospinal Fluid Dynamics ◽  
Nerve Roots ◽  
The Impact

scholarly journals Impact of Neurapheresis System on Intrathecal Cerebrospinal Fluid Dynamics: A Computational Fluid Dynamics Study

2019 ◽  
Vol 142 (2) ◽  
Author(s):  
Mohammadreza Khani ◽  
Lucas R. Sass ◽  
Aaron R. McCabe ◽  
Laura M. Zitella Verbick ◽  
Shivanand P. Lad ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Cerebrospinal Fluid ◽  
Removal Rate ◽  
Maximum Flow ◽  
Cfd Model ◽  
Flow Loop ◽  
Steady Streaming ◽  
Lumbar Drain ◽  
The Impact

Abstract It has been hypothesized that early and rapid filtration of blood from cerebrospinal fluid (CSF) in postsubarachnoid hemorrhage patients may reduce hospital stay and related adverse events. In this study, we formulated a subject-specific computational fluid dynamics (CFD) model to parametrically investigate the impact of a novel dual-lumen catheter-based CSF filtration system, the Neurapheresis™ system (Minnetronix Neuro, Inc., St. Paul, MN), on intrathecal CSF dynamics. The operating principle of this system is to remove CSF from one location along the spine (aspiration port), externally filter the CSF routing the retentate to a waste bag, and return permeate (uncontaminated CSF) to another location along the spine (return port). The CFD model allowed parametric simulation of how the Neurapheresis system impacts intrathecal CSF velocities and steady–steady streaming under various Neurapheresis flow settings ranging from 0.5 to 2.0 ml/min and with a constant retentate removal rate of 0.2 ml/min simulation of the Neurapheresis system were compared to a lumbar drain simulation with a typical CSF removal rate setting of 0.2 ml/min. Results showed that the Neurapheresis system at a maximum flow of 2.0 ml/min increased average steady streaming CSF velocity 2× in comparison to lumbar drain (0.190 ± 0.133 versus 0.093 ± 0.107 mm/s, respectively). This affect was localized to the region within the Neurapheresis flow loop. The mean velocities introduced by the flow loop were relatively small in comparison to normal cardiac-induced CSF velocities.

scholarly journals Flow induced by ependymal cilia dominates near-wall cerebrospinal fluid dynamics in the lateral ventricles

2014 ◽  
Vol 11 (94) ◽  
pp. 20131189 ◽  
Author(s):  
Bercan Siyahhan ◽  
Verena Knobloch ◽  
Diane de Zélicourt ◽  
Mahdi Asgari ◽  
Marianne Schmid Daners ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Cerebrospinal Fluid ◽  
Choroid Plexus ◽  
Wall Motion ◽  
Csf Flow ◽  
Csf Dynamics ◽  
Lateral Ventricles ◽  
Ependymal Cilia ◽  
Neuronal Guidance ◽  
Near Wall

While there is growing experimental evidence that cerebrospinal fluid (CSF) flow induced by the beating of ependymal cilia is an important factor for neuronal guidance, the respective contribution of vascular pulsation-driven macroscale oscillatory CSF flow remains unclear. This work uses computational fluid dynamics to elucidate the interplay between macroscale and cilia-induced CSF flows and their relative impact on near-wall dynamics. Physiological macroscale CSF dynamics are simulated in the ventricular space using subject-specific anatomy, wall motion and choroid plexus pulsations derived from magnetic resonance imaging. Near-wall flow is quantified in two subdomains selected from the right lateral ventricle, for which dynamic boundary conditions are extracted from the macroscale simulations. When cilia are neglected, CSF pulsation leads to periodic flow reversals along the ventricular surface, resulting in close to zero time-averaged force on the ventricle wall. The cilia promote more aligned wall shear stresses that are on average two orders of magnitude larger compared with those produced by macroscopic pulsatile flow. These findings indicate that CSF flow-mediated neuronal guidance is likely to be dominated by the action of the ependymal cilia in the lateral ventricles, whereas CSF dynamics in the centre regions of the ventricles is driven predominantly by wall motion and choroid plexus pulsation.

scholarly journals Syringomyelia secondary to cervical spondylosis: Case report and review of literature

2014 ◽  
Vol 05 (S 01) ◽  
pp. S078-S082 ◽  
Author(s):  
Savitr Sastri Bhagavathula Venkata ◽  
Arivazhagan Arimappamagan ◽  
Spiros Lafazanos ◽  
Nupur Pruthi
Keyword(s):  
Spinal Cord ◽  
Cerebrospinal Fluid ◽  
Cervical Spondylosis ◽  
Cine Mri ◽  
Rare Entity ◽  
Causal Association ◽  
Review Of Literature ◽  
Csf Flow ◽  
Spinal Subarachnoid Space ◽  
Intensity Changes

ABSTRACTSyringomyelia secondary to cervical spondylosis is a rare entity to encounter in clinical practice. We discuss the case of a 53-year-old lady who presented with a syringomyelic syndrome and was found to have cervical spondylosis on imaging. Cine-MRI revealed an obstruction of cerebrospinal fluid (CSF) flow in the cervical spinal subarachnoid space. Decompression of the same led to clinical and radiological improvement. There is a potential causal association between cervical spondylosis and syringomyelia. MRI CSF flow studies may help in deciding the course of treatment in such cases. A subset of patients with cervical spondylosis and concurrent spinal cord signal intensity changes may show reversal of the same following intervention.

scholarly journals In vitro and Numerical Simulation of Blood Removal from Cerebrospinal Fluid: Comparison of Lumbar Drain to Neurapheresis Therapy

2020 ◽  
Author(s):  
Mohammadreza Khani ◽  
Lucas Sass ◽  
M. Keith Sharp ◽  
Aaron McCabe ◽  
Laura Zitella Verbick ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Solute Transport ◽  
Cfd Model ◽  
Tracer Concentration ◽  
Steady Streaming ◽  
Lumbar Drain ◽  
Subject Specific ◽  
Multiphase Cfd ◽  
The Impact

Abstract Background: Blood removal from cerebrospinal fluid (CSF) in post-subarachnoid hemorrhage patients may reduce the risk of related secondary brain injury. We formulated a computational fluid dynamics (CFD) model to investigate the impact of a dual-lumen catheter-based CSF filtration system, called NeurapheresisTM therapy, on blood removal from CSF compared to lumbar drain. Methods: A subject-specific multiphase CFD model of CSF system-wide solute transport was constructed based on MRI measurements. The Neurapheresis catheter geometry was added to the model within the spinal subarachnoid space (SAS). Neurapheresis flow aspiration and return rate was 2.0 and 1.8 mL/min, versus 0.2 mL/min drainage for lumbar drain. Blood was modeled as a bulk fluid phase within CSF with a 10% initial tracer concentration and identical viscosity and density as CSF. Subject-specific oscillatory CSF flow was applied at the model inlet. The dura and spinal cord geometry were considered to be stationary. Spatial-temporal tracer concentration was quantified based on time-average steady-streaming velocities throughout the domain under Neurapheresis therapy and lumbar drain. To help verify CFD results, an optically clear in vitro CSF model was constructed with fluorescein used as a blood surrogate. Quantitative comparison of numerical and in vitro results was performed by linear regression of spatial-temporal tracer concentration over 24-hours.Results: After 24-hours, tracer concentration was reduced to 4.9% under Neurapheresis therapy compared to 6.5% under lumbar drain. Tracer clearance was most rapid between the catheter aspiration and return ports. Neurapheresis therapy was found to have a greater impact on steady-streaming compared to lumbar drain. Steady-streaming in the cranial SAS was ~50X smaller than in the spinal SAS for both cases. CFD results were strongly correlated with the in vitro spatial-temporal tracer concentration under Neurapheresis therapy (R2=0.89 with +2.13% and -1.93% tracer concentration confidence interval). Conclusion: A subject-specific CFD model of CSF system-wide solute transport was used to investigate the impact of Neurapheresis therapy on tracer removal from CSF compared to lumbar drain over a 24-hour period. Neurapheresis therapy was found to substantially increase tracer clearance compared to lumbar drain. The multiphase CFD results were verified by in vitro fluorescein tracer experiments.

Evaluation of the central canal of the spinal cord in experimentally induced hydrocephalus

1978 ◽  
Vol 48 (6) ◽  
pp. 970-974 ◽  
Author(s):  
A. Everette James ◽  
William J. Flor ◽  
Gary R. Novak ◽  
Ernst-Peter Strecker ◽  
Barry Burns
Keyword(s):  
Spinal Cord ◽  
Cerebrospinal Fluid ◽  
Experimental Model ◽  
Alternative Pathway ◽  
Central Canal ◽  
Communicating Hydrocephalus ◽  
Csf Flow ◽  
Content Type ◽  
Histological Appearance ◽  
Fine Print

✓ The central canal of the spinal cord has been proposed as a significant compensatory alternative pathway of cerebrospinal fluid (CSF) flow in hydrocephalus. Ten dogs were made hydrocephalic by a relatively atraumatic experimental model that simulates the human circumstance of chronic communicating hydrocephalus. The central canal was studied by histopathology and compared with 10 normal control dogs. In both groups the central canal of the spinal cord was normal in size, configuration, and histological appearance. In this experimental model dilatation of the canal and increased movement of CSF does not appear to be a compensatory alternative pathway.

Unknown fatal encephalomyelopolyradiculoneuritis in a child. A case report

2021 ◽  
Vol 2 (2) ◽  
pp. 100-106
Author(s):  
Aleksandra I. Pavlyuchkova ◽  
Aleksey S. Kotov
Keyword(s):  
Spinal Cord ◽  
Cerebrospinal Fluid ◽  
Genetic Diseases ◽  
Cranial Nerves ◽  
Unknown Etiology ◽  
Active Therapy ◽  
Nerve Roots ◽  
Child Patient ◽  
Brain And Spinal Cord ◽  
The Brain

In childhood, various infectious, autoimmune, genetic diseases can manifest. We present a case of fatal encephalomyelopolyradiculoneuritis of unknown etiology in a 9-year-old child. Patient N.K. in February 2019, noted an increase in temperature to subfebrile values, received symptomatic and antibiotic therapy without effect. An increase in protein and lymphocytes was found in the cerebrospinal fluid. According to MRI data, the emergence of more and more foci of the pathological signal in the brain and spinal cord, cranial nerves and nerve roots of the lumbar plexus was noted. Known infectious and autoimmune diseases were excluded. Despite active therapy with glucocorticoids, antibiotics, antiviral drugs, immunoglobulin, the disease continued to progress, and the patient died in April 2020.

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