The Experts below are selected from a list of 666 Experts worldwide ranked by ideXlab platform

Per Kristian Eide - One of the best experts on this subject based on the ideXlab platform.

  • delayed clearance of cerebrospinal fluid tracer from entorhinal cortex in idiopathic normal pressure hydrocephalus a Glymphatic magnetic resonance imaging study
    Journal of Cerebral Blood Flow and Metabolism, 2019
    Co-Authors: Geir Ringstad, Per Kristian Eide
    Abstract:

    The Glymphatic System plays a key role for clearance of waste solutes from the rodent brain. We recently found evidence of Glymphatic circulation in the human brain when using magnetic resonance im...

  • the human visual pathway communicates directly with the subarachnoid space
    Investigative Ophthalmology & Visual Science, 2019
    Co-Authors: Henrik Holvin Jacobsen, Geir Ringstad, Oystein Kalsnes Jorstad, Tiril Sandell, Per Kristian Eide
    Abstract:

    Purpose: Explore in vivo whether there is direct communication between the cerebrospinal fluid (CSF) and extravascular compartment of human visual pathway structures. Methods: A prospective and observational study included 10 subjects who underwent intrathecal gadolinium-enhanced magnetic resonance imaging (MRI) for suspected CSF circulation disorder, but with a negative result and with no known ophthalmic diseases. After precontrast T1-weighted MRI, 0.5 mL of gadobutrol (Gadovist, 1.0 mmol/mL) was injected intrathecally. Gadobutrol distributes in the extravascular space, and served as a CSF tracer. Consecutive MRI scans were obtained throughout 24 to 48 hours. To assess gadobutrol contrast enrichment, regions of interest (ROIs) were placed at multiple locations along the visual pathway, from the primary visual cortex to the eye's vitreous body. CSF tracer dependent T1 signal was measured in each ROI. A linear mixed-model was used for statistical analyses. Results: CSF tracer enrichment was found within the optic nerve, optic chiasm, optic tract, and primary visual cortex (P < 0.001). Peak tracer enrichment in the visual pathway generally occurred after 24 hours and was preceded by peak enhancement in the prechiasmatic cistern after 4 to 6 hours. Conclusions: The results indicate direct communication between CSF of subarachnoid space and the extravascular space of the human visual pathway. Extravascular entry of the CSF tracer is a prerequisite for a Glymphatic System, the present findings may suggest its presence. The existence of a Glymphatic System in the human visual pathway could bring novel perspectives on the pathophysiology and treatment of ophthalmic diseases.

  • the human visual pathway communicates directly with the subarachnoid space
    Investigative Ophthalmology & Visual Science, 2019
    Co-Authors: Henrik Holvin Jacobsen, Geir Ringstad, Oystein Kalsnes Jorstad, Tiril Sandell, Per Kristian Eide
    Abstract:

    Purpose: Explore in vivo whether there is direct communication between the cerebrospinal fluid (CSF) and extravascular compartment of human visual pathway structures. Methods: A prospective and observational study included 10 subjects who underwent intrathecal gadolinium-enhanced magnetic resonance imaging (MRI) for suspected CSF circulation disorder, but with a negative result and with no known ophthalmic diseases. After precontrast T1-weighted MRI, 0.5 mL of gadobutrol (Gadovist, 1.0 mmol/mL) was injected intrathecally. Gadobutrol distributes in the extravascular space, and served as a CSF tracer. Consecutive MRI scans were obtained throughout 24 to 48 hours. To assess gadobutrol contrast enrichment, regions of interest (ROIs) were placed at multiple locations along the visual pathway, from the primary visual cortex to the eye's vitreous body. CSF tracer dependent T1 signal was measured in each ROI. A linear mixed-model was used for statistical analyses. Results: CSF tracer enrichment was found within the optic nerve, optic chiasm, optic tract, and primary visual cortex (P < 0.001). Peak tracer enrichment in the visual pathway generally occurred after 24 hours and was preceded by peak enhancement in the prechiasmatic cistern after 4 to 6 hours. Conclusions: The results indicate direct communication between CSF of subarachnoid space and the extravascular space of the human visual pathway. Extravascular entry of the CSF tracer is a prerequisite for a Glymphatic System, the present findings may suggest its presence. The existence of a Glymphatic System in the human visual pathway could bring novel perspectives on the pathophysiology and treatment of ophthalmic diseases.

  • mri with intrathecal mri gadolinium contrast medium administration a possible method to assess Glymphatic function in human brain
    Acta radiologica short reports, 2015
    Co-Authors: Per Kristian Eide, Geir Ringstad
    Abstract:

    Recently, the “Glymphatic System” of the brain has been discovered in rodents, which is a paravascular, transparenchymal route for clearance of excess brain metabolites and distribution of compounds in the cerebrospinal fluid. It has already been demonstrated that intrathecally administered gadolinium (Gd) contrast medium distributes along this route in rats, but so far not in humans. A 27-year-old woman underwent magnetic resonance imaging (MRI) with intrathecal administration of gadobutrol, which distributed throughout her entire brain after 1 and 4.5 h. MRI with intrathecal Gd may become a tool to study Glymphatic function in the human brain.

Geir Ringstad - One of the best experts on this subject based on the ideXlab platform.

  • delayed clearance of cerebrospinal fluid tracer from entorhinal cortex in idiopathic normal pressure hydrocephalus a Glymphatic magnetic resonance imaging study
    Journal of Cerebral Blood Flow and Metabolism, 2019
    Co-Authors: Geir Ringstad, Per Kristian Eide
    Abstract:

    The Glymphatic System plays a key role for clearance of waste solutes from the rodent brain. We recently found evidence of Glymphatic circulation in the human brain when using magnetic resonance im...

  • the human visual pathway communicates directly with the subarachnoid space
    Investigative Ophthalmology & Visual Science, 2019
    Co-Authors: Henrik Holvin Jacobsen, Geir Ringstad, Oystein Kalsnes Jorstad, Tiril Sandell, Per Kristian Eide
    Abstract:

    Purpose: Explore in vivo whether there is direct communication between the cerebrospinal fluid (CSF) and extravascular compartment of human visual pathway structures. Methods: A prospective and observational study included 10 subjects who underwent intrathecal gadolinium-enhanced magnetic resonance imaging (MRI) for suspected CSF circulation disorder, but with a negative result and with no known ophthalmic diseases. After precontrast T1-weighted MRI, 0.5 mL of gadobutrol (Gadovist, 1.0 mmol/mL) was injected intrathecally. Gadobutrol distributes in the extravascular space, and served as a CSF tracer. Consecutive MRI scans were obtained throughout 24 to 48 hours. To assess gadobutrol contrast enrichment, regions of interest (ROIs) were placed at multiple locations along the visual pathway, from the primary visual cortex to the eye's vitreous body. CSF tracer dependent T1 signal was measured in each ROI. A linear mixed-model was used for statistical analyses. Results: CSF tracer enrichment was found within the optic nerve, optic chiasm, optic tract, and primary visual cortex (P < 0.001). Peak tracer enrichment in the visual pathway generally occurred after 24 hours and was preceded by peak enhancement in the prechiasmatic cistern after 4 to 6 hours. Conclusions: The results indicate direct communication between CSF of subarachnoid space and the extravascular space of the human visual pathway. Extravascular entry of the CSF tracer is a prerequisite for a Glymphatic System, the present findings may suggest its presence. The existence of a Glymphatic System in the human visual pathway could bring novel perspectives on the pathophysiology and treatment of ophthalmic diseases.

  • the human visual pathway communicates directly with the subarachnoid space
    Investigative Ophthalmology & Visual Science, 2019
    Co-Authors: Henrik Holvin Jacobsen, Geir Ringstad, Oystein Kalsnes Jorstad, Tiril Sandell, Per Kristian Eide
    Abstract:

    Purpose: Explore in vivo whether there is direct communication between the cerebrospinal fluid (CSF) and extravascular compartment of human visual pathway structures. Methods: A prospective and observational study included 10 subjects who underwent intrathecal gadolinium-enhanced magnetic resonance imaging (MRI) for suspected CSF circulation disorder, but with a negative result and with no known ophthalmic diseases. After precontrast T1-weighted MRI, 0.5 mL of gadobutrol (Gadovist, 1.0 mmol/mL) was injected intrathecally. Gadobutrol distributes in the extravascular space, and served as a CSF tracer. Consecutive MRI scans were obtained throughout 24 to 48 hours. To assess gadobutrol contrast enrichment, regions of interest (ROIs) were placed at multiple locations along the visual pathway, from the primary visual cortex to the eye's vitreous body. CSF tracer dependent T1 signal was measured in each ROI. A linear mixed-model was used for statistical analyses. Results: CSF tracer enrichment was found within the optic nerve, optic chiasm, optic tract, and primary visual cortex (P < 0.001). Peak tracer enrichment in the visual pathway generally occurred after 24 hours and was preceded by peak enhancement in the prechiasmatic cistern after 4 to 6 hours. Conclusions: The results indicate direct communication between CSF of subarachnoid space and the extravascular space of the human visual pathway. Extravascular entry of the CSF tracer is a prerequisite for a Glymphatic System, the present findings may suggest its presence. The existence of a Glymphatic System in the human visual pathway could bring novel perspectives on the pathophysiology and treatment of ophthalmic diseases.

  • mri with intrathecal mri gadolinium contrast medium administration a possible method to assess Glymphatic function in human brain
    Acta radiologica short reports, 2015
    Co-Authors: Per Kristian Eide, Geir Ringstad
    Abstract:

    Recently, the “Glymphatic System” of the brain has been discovered in rodents, which is a paravascular, transparenchymal route for clearance of excess brain metabolites and distribution of compounds in the cerebrospinal fluid. It has already been demonstrated that intrathecally administered gadolinium (Gd) contrast medium distributes along this route in rats, but so far not in humans. A 27-year-old woman underwent magnetic resonance imaging (MRI) with intrathecal administration of gadobutrol, which distributed throughout her entire brain after 1 and 4.5 h. MRI with intrathecal Gd may become a tool to study Glymphatic function in the human brain.

Henrik Holvin Jacobsen - One of the best experts on this subject based on the ideXlab platform.

  • the human visual pathway communicates directly with the subarachnoid space
    Investigative Ophthalmology & Visual Science, 2019
    Co-Authors: Henrik Holvin Jacobsen, Geir Ringstad, Oystein Kalsnes Jorstad, Tiril Sandell, Per Kristian Eide
    Abstract:

    Purpose: Explore in vivo whether there is direct communication between the cerebrospinal fluid (CSF) and extravascular compartment of human visual pathway structures. Methods: A prospective and observational study included 10 subjects who underwent intrathecal gadolinium-enhanced magnetic resonance imaging (MRI) for suspected CSF circulation disorder, but with a negative result and with no known ophthalmic diseases. After precontrast T1-weighted MRI, 0.5 mL of gadobutrol (Gadovist, 1.0 mmol/mL) was injected intrathecally. Gadobutrol distributes in the extravascular space, and served as a CSF tracer. Consecutive MRI scans were obtained throughout 24 to 48 hours. To assess gadobutrol contrast enrichment, regions of interest (ROIs) were placed at multiple locations along the visual pathway, from the primary visual cortex to the eye's vitreous body. CSF tracer dependent T1 signal was measured in each ROI. A linear mixed-model was used for statistical analyses. Results: CSF tracer enrichment was found within the optic nerve, optic chiasm, optic tract, and primary visual cortex (P < 0.001). Peak tracer enrichment in the visual pathway generally occurred after 24 hours and was preceded by peak enhancement in the prechiasmatic cistern after 4 to 6 hours. Conclusions: The results indicate direct communication between CSF of subarachnoid space and the extravascular space of the human visual pathway. Extravascular entry of the CSF tracer is a prerequisite for a Glymphatic System, the present findings may suggest its presence. The existence of a Glymphatic System in the human visual pathway could bring novel perspectives on the pathophysiology and treatment of ophthalmic diseases.

  • the human visual pathway communicates directly with the subarachnoid space
    Investigative Ophthalmology & Visual Science, 2019
    Co-Authors: Henrik Holvin Jacobsen, Geir Ringstad, Oystein Kalsnes Jorstad, Tiril Sandell, Per Kristian Eide
    Abstract:

    Purpose: Explore in vivo whether there is direct communication between the cerebrospinal fluid (CSF) and extravascular compartment of human visual pathway structures. Methods: A prospective and observational study included 10 subjects who underwent intrathecal gadolinium-enhanced magnetic resonance imaging (MRI) for suspected CSF circulation disorder, but with a negative result and with no known ophthalmic diseases. After precontrast T1-weighted MRI, 0.5 mL of gadobutrol (Gadovist, 1.0 mmol/mL) was injected intrathecally. Gadobutrol distributes in the extravascular space, and served as a CSF tracer. Consecutive MRI scans were obtained throughout 24 to 48 hours. To assess gadobutrol contrast enrichment, regions of interest (ROIs) were placed at multiple locations along the visual pathway, from the primary visual cortex to the eye's vitreous body. CSF tracer dependent T1 signal was measured in each ROI. A linear mixed-model was used for statistical analyses. Results: CSF tracer enrichment was found within the optic nerve, optic chiasm, optic tract, and primary visual cortex (P < 0.001). Peak tracer enrichment in the visual pathway generally occurred after 24 hours and was preceded by peak enhancement in the prechiasmatic cistern after 4 to 6 hours. Conclusions: The results indicate direct communication between CSF of subarachnoid space and the extravascular space of the human visual pathway. Extravascular entry of the CSF tracer is a prerequisite for a Glymphatic System, the present findings may suggest its presence. The existence of a Glymphatic System in the human visual pathway could bring novel perspectives on the pathophysiology and treatment of ophthalmic diseases.

Oystein Kalsnes Jorstad - One of the best experts on this subject based on the ideXlab platform.

  • the human visual pathway communicates directly with the subarachnoid space
    Investigative Ophthalmology & Visual Science, 2019
    Co-Authors: Henrik Holvin Jacobsen, Geir Ringstad, Oystein Kalsnes Jorstad, Tiril Sandell, Per Kristian Eide
    Abstract:

    Purpose: Explore in vivo whether there is direct communication between the cerebrospinal fluid (CSF) and extravascular compartment of human visual pathway structures. Methods: A prospective and observational study included 10 subjects who underwent intrathecal gadolinium-enhanced magnetic resonance imaging (MRI) for suspected CSF circulation disorder, but with a negative result and with no known ophthalmic diseases. After precontrast T1-weighted MRI, 0.5 mL of gadobutrol (Gadovist, 1.0 mmol/mL) was injected intrathecally. Gadobutrol distributes in the extravascular space, and served as a CSF tracer. Consecutive MRI scans were obtained throughout 24 to 48 hours. To assess gadobutrol contrast enrichment, regions of interest (ROIs) were placed at multiple locations along the visual pathway, from the primary visual cortex to the eye's vitreous body. CSF tracer dependent T1 signal was measured in each ROI. A linear mixed-model was used for statistical analyses. Results: CSF tracer enrichment was found within the optic nerve, optic chiasm, optic tract, and primary visual cortex (P < 0.001). Peak tracer enrichment in the visual pathway generally occurred after 24 hours and was preceded by peak enhancement in the prechiasmatic cistern after 4 to 6 hours. Conclusions: The results indicate direct communication between CSF of subarachnoid space and the extravascular space of the human visual pathway. Extravascular entry of the CSF tracer is a prerequisite for a Glymphatic System, the present findings may suggest its presence. The existence of a Glymphatic System in the human visual pathway could bring novel perspectives on the pathophysiology and treatment of ophthalmic diseases.

  • the human visual pathway communicates directly with the subarachnoid space
    Investigative Ophthalmology & Visual Science, 2019
    Co-Authors: Henrik Holvin Jacobsen, Geir Ringstad, Oystein Kalsnes Jorstad, Tiril Sandell, Per Kristian Eide
    Abstract:

    Purpose: Explore in vivo whether there is direct communication between the cerebrospinal fluid (CSF) and extravascular compartment of human visual pathway structures. Methods: A prospective and observational study included 10 subjects who underwent intrathecal gadolinium-enhanced magnetic resonance imaging (MRI) for suspected CSF circulation disorder, but with a negative result and with no known ophthalmic diseases. After precontrast T1-weighted MRI, 0.5 mL of gadobutrol (Gadovist, 1.0 mmol/mL) was injected intrathecally. Gadobutrol distributes in the extravascular space, and served as a CSF tracer. Consecutive MRI scans were obtained throughout 24 to 48 hours. To assess gadobutrol contrast enrichment, regions of interest (ROIs) were placed at multiple locations along the visual pathway, from the primary visual cortex to the eye's vitreous body. CSF tracer dependent T1 signal was measured in each ROI. A linear mixed-model was used for statistical analyses. Results: CSF tracer enrichment was found within the optic nerve, optic chiasm, optic tract, and primary visual cortex (P < 0.001). Peak tracer enrichment in the visual pathway generally occurred after 24 hours and was preceded by peak enhancement in the prechiasmatic cistern after 4 to 6 hours. Conclusions: The results indicate direct communication between CSF of subarachnoid space and the extravascular space of the human visual pathway. Extravascular entry of the CSF tracer is a prerequisite for a Glymphatic System, the present findings may suggest its presence. The existence of a Glymphatic System in the human visual pathway could bring novel perspectives on the pathophysiology and treatment of ophthalmic diseases.

Jeffrey J Iliff - One of the best experts on this subject based on the ideXlab platform.

  • linking traumatic brain injury sleep disruption and post traumatic headache a potential role for Glymphatic pathway dysfunction
    Current Pain and Headache Reports, 2019
    Co-Authors: Juan Piantino, Miranda M Lim, Craig D Newgard, Jeffrey J Iliff
    Abstract:

    Traumatic brain injury (TBI) is a major public health concern in the USA and worldwide. Sleep disruption and headaches are two of the most common problems reported by patients after TBI. In this manuscript, we review the current knowledge regarding the relation between post-traumatic sleep disruption and headaches. We also describe the role of the Glymphatic System as a potential link between TBI, sleep, and headaches. Recent studies show a reciprocal relation between post-traumatic sleep disruption and headaches: patients with sleep disruption after TBI report more headaches, and post-traumatic headaches are a risk factor for developing disrupted sleep. Despite this clinical association, the exact mechanisms linking post-traumatic sleep disruption and headaches are not well understood. The Glymphatic pathway, a newly described brain–wide network of perivascular spaces that supports the clearance of interstitial solutes and wastes from the brain, is active primarily during sleep, and becomes dysfunctional after TBI. We propose a model where changes in Glymphatic function caused by TBI and post-traumatic sleep disruption may impair the clearance of neuropeptides involved in the pathogenesis of post-traumatic headaches, such as CGRP. The relation between TBI, post-traumatic sleep disruption, and post-traumatic headaches, although well documented in the literature, remains poorly understood. Dysfunction of the Glymphatic System caused by TBI offers a novel and exiting explanation to this clinically observed phenomenon. The proposed model, although theoretical, could provide important mechanistic insights to the TBI-sleep-headache association.

  • The Glymphatic System and Brain Interstitial Fluid Homeostasis
    Primer on Cerebrovascular Diseases, 2017
    Co-Authors: Jeffrey J Iliff, A. S. Thrane, M. Nedergaard
    Abstract:

    This chapter reviews the basis of brain interstitial fluid homeostasis and discusses the roles of the Glymphatic System in the clearance of fluid and solutes. The anatomical organization of the Glymphatic System and its drainage into cervical and meningeal lymph vessels, as well as the role of astrocytes, the perivascular space, and the sleep–wake cycle in the regulation of interstitial space and bulk flow, are described. The existence of the Glymphatic System opens up new ways to understand the mechanisms underlying brain fluid dynamics and acute edema formation following stroke. Influx of cerebrospinal fluid along the perivascular spaces surrounding cerebral arteries and failure of ischemic cells to clear excess interstitial fluid, as well as perivasculitis, likely contribute to cytotoxic and vasogenic brain edema. As such, diagnostic imaging or manipulation of the Glymphatic pathway may unlock novel therapeutic opportunities for cerebrovascular disease.

  • evaluating Glymphatic pathway function utilizing clinically relevant intrathecal infusion of csf tracer
    Journal of Translational Medicine, 2013
    Co-Authors: Jeffrey J Iliff, Lijun Yang, Benjamin T Kress, Harris J Weber, Meenakshisundaram Thiyagarajan, Baozhi Wang, Rashid Deane, Helene Benveniste
    Abstract:

    Background Neurodegenerative diseases such as Alzheimer’s are associated with the aggregation of endogenous peptides and proteins that contribute to neuronal dysfunction and loss. The Glymphatic System, a brain-wide perivascular pathway along which cerebrospinal fluid (CSF) and interstitial fluid (ISF) rapidly exchange, has recently been identified as a key contributor to the clearance of interstitial solutes from the brain, including amyloid β. These findings suggest that measuring changes in Glymphatic pathway function may be an important prognostic for evaluating neurodegenerative disease susceptibility or progression. However, no clinically acceptable approach to evaluate Glymphatic pathway function in humans has yet been developed.