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Desmidt T, Dujardin PA, Andersson F, Brizard B, Réméniéras JP, Gissot V, Arlicot N, Barantin L, Espitalier F, Belzung C, Tanti A, Robert G, Bulteau S, Gallet Q, Kazour F, Cognet S, Camus V, El-Hage W, Poupin P, Karim HT. Changes in cerebral connectivity and brain tissue pulsations with the antidepressant response to an equimolar mixture of oxygen and nitrous oxide: an MRI and ultrasound study. Mol Psychiatry 2023; 28:3900-3908. [PMID: 37592013 DOI: 10.1038/s41380-023-02217-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 08/01/2023] [Accepted: 08/03/2023] [Indexed: 08/19/2023]
Abstract
Nitrous oxide (N2O) has recently emerged as a potential fast-acting antidepressant but the cerebral mechanisms involved in this effect remain speculative. We hypothesized that the antidepressant response to an Equimolar Mixture of Oxygen and Nitrous Oxide (EMONO) would be associated with changes in cerebral connectivity and brain tissue pulsations (BTP). Thirty participants (20 with a major depressive episode resistant to at least one antidepressant and 10 healthy controls-HC, aged 25-50, only females) were exposed to a 1-h single session of EMONO and followed for 1 week. We defined response as a reduction of at least 50% in the MADRS score 1 week after exposure. Cerebral connectivity of the Anterior Cingulate Cortex (ACC), using ROI-based resting state fMRI, and BTP, using ultrasound Tissue Pulsatility Imaging, were compared before and rapidly after exposure (as well as during exposure for BTP) among HC, non-responders and responders. We conducted analyses to compare group × time, group, and time effects. Nine (45%) depressed participants were considered responders and eleven (55%) non-responders. In responders, we observed a significant reduction in the connectivity of the subgenual ACC with the precuneus. Connectivity of the supracallosal ACC with the mid-cingulate also significantly decreased after exposure in HC and in non-responders. BTP significantly increased in the three groups between baseline and gas exposure, but the increase in BTP within the first 10 min was only significant in responders. We found that a single session of EMONO can rapidly modify the functional connectivity in the subgenual ACC-precuneus, nodes within the default mode network, in depressed participants responders to EMONO. In addition, larger increases in BTP, associated with a significant rise in cerebral blood flow, appear to promote the antidepressant response, possibly by facilitating optimal drug delivery to the brain. Our study identified potential cerebral mechanisms related to the antidepressant response of N2O, as well as potential markers for treatment response with this fast-acting antidepressant.
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Affiliation(s)
- Thomas Desmidt
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.
- CHU de Tours, Tours, France.
- CIC 1415, CHU de Tours, Inserm, Tours, France.
| | | | | | - Bruno Brizard
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
| | | | | | - Nicolas Arlicot
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
- CHU de Tours, Tours, France
| | | | - Fabien Espitalier
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
- CHU de Tours, Tours, France
| | | | - Arnaud Tanti
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
| | - Gabriel Robert
- Behavior and Basal Ganglia Host Team 4712, University of Rennes 1, Rennes, France Department of Psychiatry, Rennes University Hospital, Guillaume Régnier Hospital Centre, Rennes, France
| | - Samuel Bulteau
- Addictology and Liaison Psychiatry Department, CHU de Nantes, 44000, Nantes, France
| | - Quentin Gallet
- Department of Psychiatry, University Hospital, Angers, France
| | - François Kazour
- Department of Psychiatry, University Hospital, Angers, France
| | | | - Vincent Camus
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
- CHU de Tours, Tours, France
| | - Wissam El-Hage
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
- CHU de Tours, Tours, France
- CIC 1415, CHU de Tours, Inserm, Tours, France
| | | | - Helmet T Karim
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
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Kumosa LS. Commonly Overlooked Factors in Biocompatibility Studies of Neural Implants. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2205095. [PMID: 36596702 PMCID: PMC9951391 DOI: 10.1002/advs.202205095] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 11/16/2022] [Indexed: 06/17/2023]
Abstract
Biocompatibility of cutting-edge neural implants, surgical tools and techniques, and therapeutic technologies is a challenging concept that can be easily misjudged. For example, neural interfaces are routinely gauged on how effectively they determine active neurons near their recording sites. Tissue integration and toxicity of neural interfaces are frequently assessed histologically in animal models to determine tissue morphological and cellular changes in response to surgical implantation and chronic presence. A disconnect between histological and efficacious biocompatibility exists, however, as neuronal numbers frequently observed near electrodes do not match recorded neuronal spiking activity. The downstream effects of the myriad surgical and experimental factors involved in such studies are rarely examined when deciding whether a technology or surgical process is biocompatible. Such surgical factors as anesthesia, temperature excursions, bleed incidence, mechanical forces generated, and metabolic conditions are known to have strong systemic and thus local cellular and extracellular consequences. Many tissue markers are extremely sensitive to the physiological state of cells and tissues, thus significantly impacting histological accuracy. This review aims to shed light on commonly overlooked factors that can have a strong impact on the assessment of neural biocompatibility and to address the mismatch between results stemming from functional and histological methods.
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Affiliation(s)
- Lucas S. Kumosa
- Neuronano Research CenterDepartment of Experimental Medical ScienceMedical FacultyLund UniversityMedicon Village, Byggnad 404 A2, Scheelevägen 8Lund223 81Sweden
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Almudayni A, Alharbi M, Chowdhury A, Ince J, Alablani F, Minhas JS, Lecchini-Visintini A, Chung EML. Magnetic resonance imaging of the pulsing brain: a systematic review. MAGMA (NEW YORK, N.Y.) 2023; 36:3-14. [PMID: 36242710 PMCID: PMC9992013 DOI: 10.1007/s10334-022-01043-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 09/15/2022] [Accepted: 10/03/2022] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To perform a systematic review of the literature exploring magnetic resonance imaging (MRI) methods for measuring natural brain tissue pulsations (BTPs) in humans. METHODS A prospective systematic search of MEDLINE, SCOPUS and OpenGrey databases was conducted by two independent reviewers using a pre-determined strategy. The search focused on identifying reported measurements of naturally occurring BTP motion in humans. Studies involving non-human participants, MRI in combination with other modalities, MRI during invasive procedures and MRI studies involving externally applied tests were excluded. Data from the retrieved records were combined to create Forest plots comparing brain tissue displacement between Chiari-malformation type 1 (CM-I) patients and healthy controls using an independent samples t-test. RESULTS The search retrieved 22 eligible articles. Articles described 5 main MRI techniques for visualisation or quantification of intrinsic brain motion. MRI techniques generally agreed that the amplitude of BTPs varies regionally from 0.04 mm to ~ 0.80 mm, with larger tissue displacements occurring closer to the centre and base of the brain compared to peripheral regions. Studies of brain pathology using MRI BTP measurements are currently limited to tumour characterisation, idiopathic intracranial hypertension (IIH), and CM-I. A pooled analysis confirmed that displacement of tissue in the cerebellar tonsillar region of CM-I patients was + 0.31 mm [95% CI 0.23, 0.38, p < 0.0001] higher than in healthy controls. DISCUSSION MRI techniques used for measurements of brain motion are at an early stage of development with high heterogeneity across the methods used. Further work is required to provide normative data to support systematic BTPs characterisation in health and disease.
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Affiliation(s)
- Alanoud Almudayni
- College of Applied Medical Sciences, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia. .,Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Room 419, Robert Kilpatrick Building, Leicester Royal Infirmary, Infirmary Square, Leicester, LE1 5WW, UK.
| | - Meshal Alharbi
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Room 419, Robert Kilpatrick Building, Leicester Royal Infirmary, Infirmary Square, Leicester, LE1 5WW, UK.,College of Applied Medical Sciences, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Alimul Chowdhury
- University Hospitals of Leicester NHS Trust, Leicester, LE1 5WW, UK
| | - Jonathan Ince
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Room 419, Robert Kilpatrick Building, Leicester Royal Infirmary, Infirmary Square, Leicester, LE1 5WW, UK
| | - Fatmah Alablani
- College of Applied Medical Sciences, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia.,Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Room 419, Robert Kilpatrick Building, Leicester Royal Infirmary, Infirmary Square, Leicester, LE1 5WW, UK
| | - Jatinder Singh Minhas
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Room 419, Robert Kilpatrick Building, Leicester Royal Infirmary, Infirmary Square, Leicester, LE1 5WW, UK.,National Institute for Health Research Leicester Biomedical Research Centre, University of Leicester, Leicester, LE5 4PW, UK
| | - Andrea Lecchini-Visintini
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Room 419, Robert Kilpatrick Building, Leicester Royal Infirmary, Infirmary Square, Leicester, LE1 5WW, UK.,School of Electronics and Computer Science, University of Southampton, Southampton, SO17 1BJ, UK
| | - Emma Ming Lin Chung
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Room 419, Robert Kilpatrick Building, Leicester Royal Infirmary, Infirmary Square, Leicester, LE1 5WW, UK. .,University Hospitals of Leicester NHS Trust, Leicester, LE1 5WW, UK. .,National Institute for Health Research Leicester Biomedical Research Centre, University of Leicester, Leicester, LE5 4PW, UK. .,School of Life Course and Population Sciences, King's College London, Room 3.25a, Shepherd's House, Guy's Campus, King's College London, London, SE1 7EH, UK.
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Huotari N, Tuunanen J, Raitamaa L, Raatikainen V, Kananen J, Helakari H, Tuovinen T, Järvelä M, Kiviniemi V, Korhonen V. Cardiovascular Pulsatility Increases in Visual Cortex Before Blood Oxygen Level Dependent Response During Stimulus. Front Neurosci 2022; 16:836378. [PMID: 35185462 PMCID: PMC8853630 DOI: 10.3389/fnins.2022.836378] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 01/13/2022] [Indexed: 11/13/2022] Open
Abstract
The physiological pulsations that drive tissue fluid homeostasis are not well characterized during brain activation. Therefore, we used fast magnetic resonance encephalography (MREG) fMRI to measure full band (0–5 Hz) blood oxygen level-dependent (BOLDFB) signals during a dynamic visual task in 23 subjects. This revealed brain activity in the very low frequency (BOLDVLF) as well as in cardiac and respiratory bands. The cardiovascular hemodynamic envelope (CHe) signal correlated significantly with the visual BOLDVLF response, considered as an independent signal source in the V1-V2 visual cortices. The CHe preceded the canonical BOLDVLF response by an average of 1.3 (± 2.2) s. Physiologically, the observed CHe signal could mark increased regional cardiovascular pulsatility following vasodilation.
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Affiliation(s)
- Niko Huotari
- Oulu Functional Neuro Imaging Group, Research Unit of Medical Imaging Physics and Technology (MIPT), University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Medical Research Center (MRC), Oulu University Hospital, Oulu, Finland
- *Correspondence: Niko Huotari,
| | - Johanna Tuunanen
- Oulu Functional Neuro Imaging Group, Research Unit of Medical Imaging Physics and Technology (MIPT), University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Medical Research Center (MRC), Oulu University Hospital, Oulu, Finland
| | - Lauri Raitamaa
- Oulu Functional Neuro Imaging Group, Research Unit of Medical Imaging Physics and Technology (MIPT), University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Medical Research Center (MRC), Oulu University Hospital, Oulu, Finland
| | - Ville Raatikainen
- Oulu Functional Neuro Imaging Group, Research Unit of Medical Imaging Physics and Technology (MIPT), University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Medical Research Center (MRC), Oulu University Hospital, Oulu, Finland
| | - Janne Kananen
- Oulu Functional Neuro Imaging Group, Research Unit of Medical Imaging Physics and Technology (MIPT), University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Medical Research Center (MRC), Oulu University Hospital, Oulu, Finland
| | - Heta Helakari
- Oulu Functional Neuro Imaging Group, Research Unit of Medical Imaging Physics and Technology (MIPT), University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Medical Research Center (MRC), Oulu University Hospital, Oulu, Finland
| | - Timo Tuovinen
- Oulu Functional Neuro Imaging Group, Research Unit of Medical Imaging Physics and Technology (MIPT), University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Medical Research Center (MRC), Oulu University Hospital, Oulu, Finland
| | - Matti Järvelä
- Oulu Functional Neuro Imaging Group, Research Unit of Medical Imaging Physics and Technology (MIPT), University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Medical Research Center (MRC), Oulu University Hospital, Oulu, Finland
| | - Vesa Kiviniemi
- Oulu Functional Neuro Imaging Group, Research Unit of Medical Imaging Physics and Technology (MIPT), University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Medical Research Center (MRC), Oulu University Hospital, Oulu, Finland
| | - Vesa Korhonen
- Oulu Functional Neuro Imaging Group, Research Unit of Medical Imaging Physics and Technology (MIPT), University of Oulu, Oulu, Finland
- Department of Diagnostic Radiology, Medical Research Center (MRC), Oulu University Hospital, Oulu, Finland
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5
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Desmidt T, Dujardin PA, Brizard B, Réméniéras JP, Gissot V, Dufour-Rainfray D, Atanasova B, Kazour F, Belzung C, Camus V, El-Hage W. Decrease in ultrasound Brain Tissue Pulsations as a potential surrogate marker of response to antidepressant. J Psychiatr Res 2022; 146:186-191. [PMID: 34995994 DOI: 10.1016/j.jpsychires.2021.12.056] [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: 10/02/2021] [Revised: 12/21/2021] [Accepted: 12/30/2021] [Indexed: 11/25/2022]
Abstract
Previous cross-sectional studies found excessive Brain Tissue Pulsations (BTP) in mid-life depression, which could constitute a mechanism of brain damage in depression. However, it remains unclear whether successful antidepressant therapy restores BTP amplitudes. In this prospective study, we investigated longitudinal changes in BTP in patients with a major depressive episode (MDE), among responders and non-responders to escitalopram. Fifty-two individuals with a MDE, free of antidepressants at baseline, were included in an 8-week open-labeled escitalopram trial. Ultrasound Tissue Pulsatility Imaging (TPI) was applied to measure resting BTP and BTP reactivity in an orthostatic challenge, at baseline and at week 8. TPI data were available for 48 participants divided into responders (n = 28, 58.3%) and non-responders (n = 20, 41.7%) according to change in the MADRS score. MaxBTP significantly decreased between baseline and week 8, only in responders. In addition, changes in MaxBTP during the orthostatic challenge were no longer significant at week 8 but only in responders. Because excessive BTP constitutes a potential mechanism for brain damage, our results suggest that a successful pharmacotherapy could benefit patients to lower the risk of brain damage in individuals with depression, a population exposed to stroke, small arteries disease and brain atrophy. TPI could provide a surrogate biomarker to monitor antidepressant response and brain health in depression in clinical routine.
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Affiliation(s)
- Thomas Desmidt
- UMR 1253, IBrain, Université de Tours, Inserm, Tours, France; CHU de Tours, Tours, France.
| | | | - Bruno Brizard
- UMR 1253, IBrain, Université de Tours, Inserm, Tours, France
| | | | | | - Diane Dufour-Rainfray
- UMR 1253, IBrain, Université de Tours, Inserm, Tours, France; CHU de Tours, Tours, France
| | | | - François Kazour
- UMR 1253, IBrain, Université de Tours, Inserm, Tours, France; CHU de Tours, Tours, France
| | | | - Vincent Camus
- UMR 1253, IBrain, Université de Tours, Inserm, Tours, France; CHU de Tours, Tours, France
| | - Wissam El-Hage
- UMR 1253, IBrain, Université de Tours, Inserm, Tours, France; CIC 1415, CHU de Tours, Inserm, Tours, France; CHU de Tours, Tours, France
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6
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Siragusa MA, Rufin T, Courtois R, Belzung C, Andersson F, Brizard B, Dujardin PA, Cottier JP, Patat F, Réméniéras JP, Gissot V, El-Hage W, Camus V, Desmidt T. Left amygdala volume and brain tissue pulsatility are associated with neuroticism: an MRI and ultrasound study. Brain Imaging Behav 2021; 15:1499-1507. [PMID: 32761564 DOI: 10.1007/s11682-020-00348-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Brain changes associated with the personality trait of neuroticism have been partly elucidated. While subcortical brain volume changes, especially a larger amygdala, appear consistent in high neuroticism, functional changes, such as cerebral blood flow (CBF) differences, have shown conflicting results, possibly because of the limitations in methods of CBF measurement. In our study, we investigated changes in amygdala volume and CBF-related function associated with neuroticism in healthy and depressed subjects using both conventional magnetic resonance imaging (MRI) measures of brain volume and the innovative technique of ultrasound Tissue Pulsatility Imaging (TPI), which has a high level of detection in measuring brain tissue pulsatility (BTP). Middle-aged females with depression (n = 25) and without depression (n = 25) underwent clinical examination, magnetic resonance imaging (MRI) and ultrasound assessment (TPI). Neuroticism was positively associated with left amygdala volume and mean BTP in individuals without depression, in both simple and multiple regressions that included potential confounding factors such as age and body mass index. No association was found in the depressed group. We confirmed the role of the left amygdala in the brain physiology of neuroticism in nondepressed individuals. Moreover, we identified a novel mechanism associated with high neuroticism, namely BTP, that may reflect greater CBF and account for the increased risk of cerebrovascular disease in individuals with high neuroticism. Because neuroticism is considered a risk factor for depression, our paper provides potential objective biomarkers for the identification of subjects at risk for depression.
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Affiliation(s)
| | | | - Robert Courtois
- CRIAVS Centre-Val de Loire, CHRU de Tours, Tours, France
- Département de Psychologie, EE 1901 'Qualipsy' (Qualité de vie et Santé psychologique), Université François Rabelais de Tours, Tours, France
| | | | | | - Bruno Brizard
- UMR 1253, iBrain, Inserm, Université de Tours, Tours, France
| | | | - Jean-Philippe Cottier
- UMR 1253, iBrain, Inserm, Université de Tours, Tours, France
- CHRU de Tours, Tours, France
| | - Frédéric Patat
- UMR 1253, iBrain, Inserm, Université de Tours, Tours, France
- CHRU de Tours, Tours, France
- CIC 1415, CHU de Tours, Inserm, Tours, France
| | | | | | - Wissam El-Hage
- UMR 1253, iBrain, Inserm, Université de Tours, Tours, France
- CHRU de Tours, Tours, France
- CIC 1415, CHU de Tours, Inserm, Tours, France
| | - Vincent Camus
- UMR 1253, iBrain, Inserm, Université de Tours, Tours, France
- CHRU de Tours, Tours, France
| | - Thomas Desmidt
- UMR 1253, iBrain, Inserm, Université de Tours, Tours, France.
- CHRU de Tours, Tours, France.
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7
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Acute ischemic stroke diagnosis using brain tissue pulsations. J Neurol Sci 2020; 419:117164. [DOI: 10.1016/j.jns.2020.117164] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 08/15/2020] [Accepted: 09/28/2020] [Indexed: 01/29/2023]
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8
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Turner P, Banahan C, Alharbi M, Ince J, Venturini S, Berger S, Bnini I, Campbell J, Beach KW, Horsfield M, Oura M, Lecchini-Visintini A, Chung EML. Brain Tissue Pulsation in Healthy Volunteers. ULTRASOUND IN MEDICINE & BIOLOGY 2020; 46:3268-3278. [PMID: 32980160 DOI: 10.1016/j.ultrasmedbio.2020.08.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 07/16/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
It is well known that the brain pulses with each cardiac cycle, but interest in measuring cardiac-induced brain tissue pulsations (BTPs) is relatively recent. This study was aimed at generating BTP reference data from healthy patients for future clinical comparisons and modelling. BTPs were measured through the forehead and temporal positions as a function of age, sex, heart rate, mean arterial pressure and pulse pressure. A multivariate regression model was developed based on transcranial tissue Doppler BTP measurements from 107 healthy adults (56 male) aged from 20-81 y. A subset of 5 participants (aged 20-49 y) underwent a brain magnetic resonance imaging scan to relate the position of the ultrasound beam to anatomy. BTP amplitudes were found to vary widely between patients (from ∼4 to ∼150 µm) and were strongly associated with pulse pressure. Comparison with magnetic resonance images confirmed regional variations in BTP with depth and probe position.
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Affiliation(s)
- Poppy Turner
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK; Department of Engineering, University of Leicester, Leicester, UK
| | - Caroline Banahan
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK; Department of Medical Physics, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Meshal Alharbi
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Jonathan Ince
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Sara Venturini
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Stefanie Berger
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Imane Bnini
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - James Campbell
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Kirk W Beach
- University of Washington, Seattle, Washington, USA
| | | | | | | | - Emma M L Chung
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK; Department of Medical Physics, University Hospitals of Leicester NHS Trust, Leicester, UK; Leicester Cardiovascular Biomedical Research Centre, Leicester, UK.
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Diagnostic Ability of Radiofrequency Ultrasound in Parkinson’s Disease Compared to Conventional Transcranial Sonography and Magnetic Resonance Imaging. Diagnostics (Basel) 2020; 10:diagnostics10100778. [PMID: 33023076 PMCID: PMC7601601 DOI: 10.3390/diagnostics10100778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/28/2020] [Accepted: 09/30/2020] [Indexed: 11/17/2022] Open
Abstract
We aimed to estimate tissue displacements’ parameters in midbrain using ultrasound radiofrequency (RF) signals and to compare diagnostic ability of this RF transcranial sonography (TCS)-based dynamic features of disease affected tissues with conventional TCS (cTCS) and magnetic resonance imaging (MRI) while differentiating patients with Parkinson’s disease (PD) from healthy controls (HC). US tissue displacement waveform parametrization by RF TCS for endogenous brain tissue motion, standard neurological examination, cTCS and MRI data collection were performed for 20 PD patients and for 20 age- and sex-matched HC in a prospective manner. Three logistic regression models were constructed, and receiver operating characteristic (ROC) curve analyses were applied. The model constructed of RF TCS-based brain tissue displacement parameters—frequency of high-end spectra peak and root mean square—revealed presumably increased anisotropy in the midbrain and demonstrated rather good diagnostic ability in the PD evaluation, although it was not superior to that of the cTCS or MRI. Future studies are needed in order to establish the true place of RF TCS detected tissue displacement parameters for the evaluation of pathologically affected brain tissue.
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10
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Alharbi M, Turner P, Ince J, Oura M, Ebirim KU, Almudayni A, Lecchini-Visintini A, Minhas JS, Chung EM. The Effects of Hypocapnia on Brain Tissue Pulsations. Brain Sci 2020; 10:E614. [PMID: 32899967 PMCID: PMC7565182 DOI: 10.3390/brainsci10090614] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 09/02/2020] [Accepted: 09/03/2020] [Indexed: 11/16/2022] Open
Abstract
Hypocapnia is known to affect patients with acute stroke and plays a key role in governing cerebral autoregulation. However, the impact of hypocapnia on brain tissue pulsations (BTPs) is relatively unexplored. As BTPs are hypothesised to result from cerebrovascular resistance to the inflow of pulsatile arterial blood, it has also been hypothesised that cerebral autoregulation changes mediated by hypocapnia will alter BTP amplitude. This healthy volunteer study reports measurements of BTPs obtained using transcranial tissue Doppler (TCTD). Thirty participants underwent hyperventilation to induce mild hypocapnia. BTP amplitude, EtCO2, blood pressure, and heart rate were then analysed to explore the impact of hypocapnia on BTP amplitude. Significant changes in BTP amplitude were noted during recovery from hypocapnia, but not during the hyperventilation manoeuvre itself. However, a significant increase in heart rate and pulse pressure and decrease in mean arterial pressure were also observed to accompany hypocapnia, which may have confounded our findings. Whilst further investigation is required, the results of this study provide a starting point for better understanding of the effects of carbon dioxide levels on BTPs. Further research in this area is needed to identify the major physiological drivers of BTPs and quantify their interactions with other aspects of cerebral haemodynamics.
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Affiliation(s)
- Meshal Alharbi
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (M.A.); (P.T.); (J.I.); (A.A.); (J.S.M.)
- College of Applied Medical Sciences, King Saud bin Abdulaziz University for Health Sciences, Riyadh 14611, Saudi Arabia
| | - Poppy Turner
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (M.A.); (P.T.); (J.I.); (A.A.); (J.S.M.)
- School of Engineering, University of Leicester, Leicester LE1 7RH, UK; (K.U.E.); (A.L.-V.)
| | - Jonathan Ince
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (M.A.); (P.T.); (J.I.); (A.A.); (J.S.M.)
| | - Mitsuhiro Oura
- Nihon Kohden Corporation, Tokorozawa-shi, Saitama 359-0037, Japan;
| | - Kelechi U. Ebirim
- School of Engineering, University of Leicester, Leicester LE1 7RH, UK; (K.U.E.); (A.L.-V.)
| | - Alanoud Almudayni
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (M.A.); (P.T.); (J.I.); (A.A.); (J.S.M.)
- College of Applied Medical Sciences, King Sattam bin Abdulaziz University for Health Sciences, Kharj 11564, Saudi Arabia
| | | | - Jatinder S. Minhas
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (M.A.); (P.T.); (J.I.); (A.A.); (J.S.M.)
- University Hospitals of Leicester NHS Trust, Leicester LE1 5WW, UK
- NIHR Leicester Biomedical Research Centre, Leicester LE5 4PW, UK
| | - Emma M.L. Chung
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM) Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (M.A.); (P.T.); (J.I.); (A.A.); (J.S.M.)
- University Hospitals of Leicester NHS Trust, Leicester LE1 5WW, UK
- NIHR Leicester Biomedical Research Centre, Leicester LE5 4PW, UK
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Siragusa MA, Réméniéras JP, Bouakaz A, Escoffre JM, Patat F, Dujardin PA, Brizard B, Belzung C, Camus V, El-Hage W, Desmidt T. A systematic review of ultrasound imaging and therapy in mental disorders. Prog Neuropsychopharmacol Biol Psychiatry 2020; 101:109919. [PMID: 32169563 DOI: 10.1016/j.pnpbp.2020.109919] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 03/06/2020] [Accepted: 03/09/2020] [Indexed: 02/06/2023]
Abstract
BACKGROUND Increasing evidence suggests that ultrasound (US) imaging may provide biomarkers and therapeutic options in mental disorders. We systematically reviewed the literature to provide a global overview of the possibilities of US for psychiatry. METHODS Original English language articles published between January 2000 and September 2019 were identified through databases searching and analyzed to summarize existing evidence according to PRISMA methodology. RESULTS A total of 81 articles were included. Various US techniques and markers have been used in mental disorders, including Transcranial Doppler and Intima-Media Thickness. Most of the studies have focused on characterizing the pathophysiology of mental disorders, especially vascular physiology. Studies on therapeutic applications are still scarce. DISCUSSION US imaging has proved to be useful in characterizing vascular impairment and structural and functional brain changes in mental disorders. Preliminary findings also suggest potential interests for therapeutic applications. Growing evidence suggests that US imaging could provide a non-invasive, portable and low-cost tool for pathophysiological characterization, prognostic assessment and therapeutic applications in mental disorders.
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Affiliation(s)
| | | | - Ayache Bouakaz
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
| | | | - Frédéric Patat
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France; CHU de Tours, Tours, France; CIC 1415, CHU Tours, Inserm, Tours Cedex, France
| | | | - Bruno Brizard
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
| | | | - Vincent Camus
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France; CHU de Tours, Tours, France
| | - Wissam El-Hage
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France; CHU de Tours, Tours, France; CIC 1415, CHU Tours, Inserm, Tours Cedex, France
| | - Thomas Desmidt
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France; CHU de Tours, Tours, France.
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Ultrasonic Assessment of the Medial Temporal Lobe Tissue Displacements in Alzheimer’s Disease. Diagnostics (Basel) 2020; 10:diagnostics10070452. [PMID: 32635379 PMCID: PMC7399840 DOI: 10.3390/diagnostics10070452] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 06/30/2020] [Accepted: 07/01/2020] [Indexed: 12/31/2022] Open
Abstract
We aim to estimate brain tissue displacements in the medial temporal lobe (MTL) using backscattered ultrasound radiofrequency (US RF) signals, and to assess the diagnostic ability of brain tissue displacement parameters for the differentiation of patients with Alzheimer’s disease (AD) from healthy controls (HC). Standard neuropsychological evaluation and transcranial sonography (TCS) for endogenous brain tissue motion data collection are performed for 20 patients with AD and for 20 age- and sex-matched HC in a prospective manner. Essential modifications of our previous method in US waveform parametrization, raising the confidence of micrometer-range displacement signals in the presence of noise, are done. Four logistic regression models are constructed, and receiver operating characteristic (ROC) curve analyses are applied. All models have cut-offs from 61.0 to 68.5% and separate AD patients from HC with a sensitivity of 89.5% and a specificity of 100%. The area under a ROC curve of predicted probability in all models is excellent (from 95.2 to 95.7%). According to our models, AD patients can be differentiated from HC by a sharper morphology of some individual MTL spatial point displacements (i.e., by spreading the spectrum of displacements to the high-end frequencies with higher variability across spatial points within a region), by lower displacement amplitude differences between adjacent spatial points (i.e., lower strain), and by a higher interaction of these attributes.
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When classical music relaxes the brain: An experimental study using Ultrasound Brain Tissue Pulsatility Imaging. Int J Psychophysiol 2020; 150:29-36. [PMID: 31987868 DOI: 10.1016/j.ijpsycho.2020.01.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 01/20/2020] [Accepted: 01/21/2020] [Indexed: 01/25/2023]
Abstract
INTRODUCTION Recent evidence suggests that biomechanical parameters of the brain, such as Brain Tissue Pulsatility (BTP), could be involved in emotional reactivity. However, no study has investigated the impact of an emotional task on BTP. We used the ultrasound method of Tissue Pulsatility Imaging (TPI) to assess changes in BTP to exciting and relaxing classical music, in a musical perception task, as a validated paradigm to assess emotional reactivity. METHODS 25 healthy volunteers were exposed via earphones to four 5-minute musical excerpts (two exciting and two relaxing musical excerpts) presented in a randomized order and intersected by 5 silence periods. Measures of BTP, Heart Rate (HR) and Skin Conductance (SC) were collected during the entire task. RESULTS The BTP significantly decreased with relaxing music compared to silence, and especially with the excerpt 'Entrance of the Shades' by Minkus. The HR and SC, but not Heart Rate Variability, were also decreased with relaxing music. We found no significant effect of exciting music. DISCUSSION We report, for the first time, that classical relaxing music decreases the amplitude of the brain pulsatile movements related to cerebral blood flow and mechanical properties of the brain parenchyma, which provides further evidence of the involvement of BTP in emotional reactivity. In addition, we validate the use of TPI as a non-invasive, portable and low cost tool for studies in psychophysiology, with the potential to be implemented as a biomarker in musicotherapy trials notably.
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Quantification of Endogenous Brain Tissue Displacement Imaging by Radiofrequency Ultrasound. Diagnostics (Basel) 2020; 10:diagnostics10020057. [PMID: 31973031 PMCID: PMC7168898 DOI: 10.3390/diagnostics10020057] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 01/15/2020] [Accepted: 01/16/2020] [Indexed: 12/31/2022] Open
Abstract
The purpose of this paper is a quantification of displacement parameters used in the imaging of brain tissue endogenous motion using ultrasonic radiofrequency (RF) signals. In a preclinical study, an ultrasonic diagnostic system with RF output was equipped with dedicated signal processing software and subject head-ultrasonic transducer stabilization. This allowed the use of RF scanning frames for the calculation of micrometer-range displacements, excluding sonographer-induced motions. Analysis of quantitative displacement estimates in dynamical phantom experiments showed that displacements of 55 µm down to 2 µm were quantified as confident according to Pearson correlation between signal fragments (minimum p ≤ 0.001). The same algorithm and scanning hardware were used in experiments and clinical imaging which allows translating phantom results to Alzheimer's disease patients and healthy elderly subjects as examples. The confident quantitative displacement waveforms of six in vivo heart-cycle episodes ranged from 8 µm up to 263 µm (Pearson correlation p ≤ 0.01). Displacement time sequences showed promising possibilities to evaluate the morphology of endogenous displacement signals at each point of the scanning plane, while displacement maps-regional distribution of displacement parameters-were essential for tissue characterization.
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15
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Ince J, Alharbi M, Minhas JS, Chung EM. Ultrasound measurement of brain tissue movement in humans: A systematic review. ULTRASOUND : JOURNAL OF THE BRITISH MEDICAL ULTRASOUND SOCIETY 2019; 28:70-81. [PMID: 32528543 DOI: 10.1177/1742271x19894601] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 11/07/2019] [Indexed: 11/15/2022]
Abstract
Introduction It has long been suggested that ultrasound could be used to measure brain tissue pulsations in humans, but potential clinical applications are relatively unexplored. The aim of this systematic review was to explore and synthesise available literature on ultrasound measurement of brain tissue motion in humans. Methods Our systematic review was designed to include predefined study selection criteria, quality evaluation, and a data extraction pro-forma, registered prospectively on PROSPERO (CRD42018114117). The systematic review was conducted by two independent reviewers. Results Ten studies were eligible for the evidence synthesis and qualitative evaluation. All eligible studies confirmed that brain tissue motion over the cardiac cycle could be measured using ultrasound; however, data acquisition, analysis, and outcomes varied. The majority of studies used tissue pulsatility imaging, with the right temporal window as the acquisition point. Currently available literature is largely exploratory, with measurements of brain tissue displacement over a narrow range of health conditions and ages. Explored health conditions include orthostatic hypotension and depression. Conclusion Further studies are needed to assess variability in brain tissue motion estimates across larger cohorts of healthy subjects and in patients with various medical conditions. This would be important for informing sample size estimates to ensure future studies are appropriately powered. Future research would also benefit from a consistent framework for data analysis and reporting, to facilitate comparative research and meta-analysis. Following standardisation and further healthy participant studies, future work should focus on assessing the clinical utility of brain tissue pulsation measurements in cerebrovascular disease states.
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Affiliation(s)
- Jonathan Ince
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHIASM) Cardiovascular Sciences Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Meshal Alharbi
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHIASM) Cardiovascular Sciences Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.,College of Applied Medical Sciences, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Jatinder S Minhas
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHIASM) Cardiovascular Sciences Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.,National Institute for Health Research Leicester Biomedical Research Centre, Leicester, UK
| | - Emma Ml Chung
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHIASM) Cardiovascular Sciences Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.,National Institute for Health Research Leicester Biomedical Research Centre, Leicester, UK
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Argentati C, Morena F, Tortorella I, Bazzucchi M, Porcellati S, Emiliani C, Martino S. Insight into Mechanobiology: How Stem Cells Feel Mechanical Forces and Orchestrate Biological Functions. Int J Mol Sci 2019; 20:E5337. [PMID: 31717803 PMCID: PMC6862138 DOI: 10.3390/ijms20215337] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 10/23/2019] [Accepted: 10/25/2019] [Indexed: 12/12/2022] Open
Abstract
The cross-talk between stem cells and their microenvironment has been shown to have a direct impact on stem cells' decisions about proliferation, growth, migration, and differentiation. It is well known that stem cells, tissues, organs, and whole organisms change their internal architecture and composition in response to external physical stimuli, thanks to cells' ability to sense mechanical signals and elicit selected biological functions. Likewise, stem cells play an active role in governing the composition and the architecture of their microenvironment. Is now being documented that, thanks to this dynamic relationship, stemness identity and stem cell functions are maintained. In this work, we review the current knowledge in mechanobiology on stem cells. We start with the description of theoretical basis of mechanobiology, continue with the effects of mechanical cues on stem cells, development, pathology, and regenerative medicine, and emphasize the contribution in the field of the development of ex-vivo mechanobiology modelling and computational tools, which allow for evaluating the role of forces on stem cell biology.
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Affiliation(s)
- Chiara Argentati
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via del Giochetto, 06126 Perugia, Italy; (C.A.); (F.M.); (I.T.); (M.B.); (S.P.); (C.E.)
| | - Francesco Morena
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via del Giochetto, 06126 Perugia, Italy; (C.A.); (F.M.); (I.T.); (M.B.); (S.P.); (C.E.)
| | - Ilaria Tortorella
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via del Giochetto, 06126 Perugia, Italy; (C.A.); (F.M.); (I.T.); (M.B.); (S.P.); (C.E.)
| | - Martina Bazzucchi
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via del Giochetto, 06126 Perugia, Italy; (C.A.); (F.M.); (I.T.); (M.B.); (S.P.); (C.E.)
| | - Serena Porcellati
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via del Giochetto, 06126 Perugia, Italy; (C.A.); (F.M.); (I.T.); (M.B.); (S.P.); (C.E.)
| | - Carla Emiliani
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via del Giochetto, 06126 Perugia, Italy; (C.A.); (F.M.); (I.T.); (M.B.); (S.P.); (C.E.)
- CEMIN, Center of Excellence on Nanostructured Innovative Materials, Via del Giochetto, 06126 Perugia, Italy
| | - Sabata Martino
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via del Giochetto, 06126 Perugia, Italy; (C.A.); (F.M.); (I.T.); (M.B.); (S.P.); (C.E.)
- CEMIN, Center of Excellence on Nanostructured Innovative Materials, Via del Giochetto, 06126 Perugia, Italy
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Desmidt T, Andersson F, Brizard B, Dujardin PA, Cottier JP, Patat F, Réméniéras JP, Gissot V, El-Hage W, Camus V. Ultrasound Measures of Brain Pulsatility Correlate with Subcortical Brain Volumes in Healthy Young Adults. ULTRASOUND IN MEDICINE & BIOLOGY 2018; 44:2307-2313. [PMID: 30131259 DOI: 10.1016/j.ultrasmedbio.2018.06.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 06/20/2018] [Accepted: 06/25/2018] [Indexed: 06/08/2023]
Abstract
Increasing evidence suggests that brain pulsatility is involved in the pathophysiology of various neurological and psychiatric disorders. However, it remains unclear whether high brain pulsatility is damaging to or protective of the brain in normal conditions, and this could depend on the age of the individual and the methods used to measure brain pulsatility. The goal of our study was to investigate associations between subcortical volumes and brain pulsatility as assessed with ultrasound in healthy young adults using both a conventional method (transcranial Doppler pulsatility index [TCD-PI]) and the innovative method of tissue pulsatility imaging (TPI), which allows a high level of detection of small brain movements (micrometers). Twenty-five females aged 18-55 with no history of significant medical disorder underwent magnetic resonance imaging and ultrasound assessment. The volumes of six subcortical regions known to be particularly sensitive to change in cerebral blood flow were measured and compared with brain pulsatility as assessed with TCD-PI and TPI. TCD-PI and TPI measures positively correlated with all subcortical regions, with the caudate nucleus having the strongest association. Linear regressions found that TCD-PI and TPI measures of brain pulsatility explained 16% to 67% of the variance of the subcortical volumes. Our results suggest that a greater pulsatility as assessed with ultrasound in healthy young adults may constitute a protective factor for brain structure. Ultrasound measures of brain pulsatility may be appropriate to provide costless, non-invasive, portable and highly sensitive markers of cerebral blood flow pulsatility related to brain structure.
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Affiliation(s)
- Thomas Desmidt
- CHRU de Tours, Pôle de Psychiatrie, Tours, France; UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.
| | | | - Bruno Brizard
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
| | | | - Jean-Philippe Cottier
- CHRU de Tours, Pôle de Psychiatrie, Tours, France; UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
| | - Frédéric Patat
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France; CIC 1415, Centre d'Investigation Clinique, Inserm, CHRU de Tours, Tours, France
| | | | - Valérie Gissot
- CIC 1415, Centre d'Investigation Clinique, Inserm, CHRU de Tours, Tours, France
| | - Wissam El-Hage
- CHRU de Tours, Pôle de Psychiatrie, Tours, France; UMR 1253, iBrain, Université de Tours, Inserm, Tours, France; CIC 1415, Centre d'Investigation Clinique, Inserm, CHRU de Tours, Tours, France
| | - Vincent Camus
- CHRU de Tours, Pôle de Psychiatrie, Tours, France; UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
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18
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Angel L, Bouazzaoui B, Isingrini M, Fay S, Taconnat L, Vanneste S, Ledoux M, Gissot V, Hommet C, Andersson F, Barantin L, Cottier JP, Pasco J, Desmidt T, Patat F, Camus V, Remenieras JP. Brain tissue pulsatility mediates cognitive and electrophysiological changes in normal aging: Evidence from ultrasound tissue pulsatility imaging (TPI). Brain Cogn 2018; 123:74-80. [DOI: 10.1016/j.bandc.2018.02.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 01/19/2018] [Accepted: 02/01/2018] [Indexed: 11/15/2022]
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Brain Tissue Pulsatility is Increased in Midlife Depression: a Comparative Study Using Ultrasound Tissue Pulsatility Imaging. Neuropsychopharmacology 2017; 42:2575-2582. [PMID: 28585568 PMCID: PMC5686485 DOI: 10.1038/npp.2017.113] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 05/20/2017] [Accepted: 05/30/2017] [Indexed: 01/09/2023]
Abstract
Cerebrovascular disease (CVD) is consistently associated with late-life depression but poorly documented in midlife depression. It can be hypothesized that the relatively low sensitivity of conventional neuroimaging techniques does not allow the detection of subtle CVD in midlife depression. We used tissue pulsatility imaging (TPI), a novel ultrasound (US) neuroimaging technique that has demonstrated good sensitivity to detect changes in the pulsatility of small brain volumes, to identify early and subtle changes in brain vascular function in midlife depression. We compared the maximum and mean brain tissue pulsatility (MaxBTP and MeanBTP), as identified by TPI, between three groups of middle-aged females matched for age: patients with depression (n=25), patients with remitted depression (n=24) and community controls (n=25). MRI arterial spin labeling, white matter hyperintensities (WMHs) and transcranial doppler (TCD) were used as control conventional markers for CVD. We found no difference in the MRI and TCD measures among the three groups. In contrast, depressive patients showed an increased BTP related to the mean global brain pulsatility (MeanBTP) and no change related to large vessels (MaxBTP) in comparison with the remitted and control groups. US neuroimaging is a highly accurate method to detect brain pulsatility changes related to cerebrovascular functioning, and TPI identified an increased BTP in midlife depressed patients, suggesting early and subtle vascular impairments in this population at risk for CVD such as stroke or WMHs. Because high pulsatility could represent prodromal cerebrovascular changes that damage the brain over time, this paper provides a potential target for blocking the progression of CVD.
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Ultrasound Tissue Pulsatility Imaging Suggests Impairment in Global Brain Pulsatility and Small Vessels in Elderly Patients with Orthostatic Hypotension. J Stroke Cerebrovasc Dis 2017; 26:246-251. [DOI: 10.1016/j.jstrokecerebrovasdis.2016.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 09/03/2016] [Indexed: 11/18/2022] Open
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Vickers J, Kirkcaldie M, Phipps A, King A. Alterations in neurofilaments and the transformation of the cytoskeleton in axons may provide insight into the aberrant neuronal changes of Alzheimer’s disease. Brain Res Bull 2016; 126:324-333. [DOI: 10.1016/j.brainresbull.2016.07.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 01/09/2023]
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Kirkcaldie MTK, Collins JM. The axon as a physical structure in health and acute trauma. J Chem Neuroanat 2016; 76:9-18. [PMID: 27233660 DOI: 10.1016/j.jchemneu.2016.05.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 05/22/2016] [Accepted: 05/22/2016] [Indexed: 10/21/2022]
Abstract
The physical structure of neurons - dendrites converging on the soma, with an axon conveying activity to distant locations - is uniquely tied to their function. To perform their role, axons need to maintain structural precision in the soft, gelatinous environment of the central nervous system and the dynamic, flexible paths of nerves in the periphery. This requires close mechanical coupling between axons and the surrounding tissue, as well as an elastic, robust axoplasm resistant to pinching and flattening, and capable of sustaining transport despite physical distortion. These mechanical properties arise primarily from the properties of the internal cytoskeleton, coupled to the axonal membrane and the extracellular matrix. In particular, the two large constituents of the internal cytoskeleton, microtubules and neurofilaments, are braced against each other and flexibly interlinked by specialised proteins. Recent evidence suggests that the primary function of neurofilament sidearms is to structure the axoplasm into a linearly organised, elastic gel. This provides support and structure to the contents of axons in peripheral nerves subject to bending, protecting the relatively brittle microtubule bundles and maintaining them as transport conduits. Furthermore, a substantial proportion of axons are myelinated, and this thick jacket of membrane wrappings alters the form, function and internal composition of the axons to which it is applied. Together these structures determine the physical properties and integrity of neural tissue, both under conditions of normal movement, and in response to physical trauma. The effects of traumatic injury are directly dependent on the physical properties of neural tissue, especially axons, and because of axons' extreme structural specialisation, post-traumatic effects are usually characterised by particular modes of axonal damage. The physical realities of axons in neural tissue are integral to both normal function and their response to injury, and require specific consideration in evaluating research models of neurotrauma.
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Affiliation(s)
- Matthew T K Kirkcaldie
- School of Medicine, University of Tasmania, Australia; Wicking Dementia Research and Education Centre, Faculty of Health, University of Tasmania, Australia.
| | - Jessica M Collins
- Wicking Dementia Research and Education Centre, Faculty of Health, University of Tasmania, Australia
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Xu C, Yuan C, Stutzman E, Canton G, Comess KA, Beach KW. Quest for the Vulnerable Atheroma: Carotid Stenosis and Diametric Strain--A Feasibility Study. ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:699-716. [PMID: 26705891 PMCID: PMC4744121 DOI: 10.1016/j.ultrasmedbio.2015.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 10/05/2015] [Accepted: 11/02/2015] [Indexed: 06/05/2023]
Abstract
The Bernoulli effect may result in eruption of a vulnerable carotid atheroma, causing a stroke. We measured electrocardiography (ECG)-registered QRS intra-stenotic blood velocity and atheroma strain dynamics in carotid artery walls using ultrasonic tissue Doppler methods, providing displacement and time resolutions of 0.1 μm and 3.7 ms. Of 22 arteries, 1 had a peak systolic velocity (PSV) >280 cm/s, 4 had PSVs between 165 and 280 cm/s and 17 had PSVs <165 cm/s. Eight arteries with PSVs <65 cm/s and 4 of 9 with PSVs between 65 and 165 cm/s had normal systolic diametric expansion (0% and 7%) and corresponding systolic wall thinning. The remaining 10 arteries had abnormal systolic strain dynamics, 2 with diametric reduction (>-0.05 mm), 2 with extreme wall expansion (>0.1 mm), 2 with extreme wall thinning (>-0.1 mm) and 4 with combinations. Decreases in systolic diameter and/or extreme systolic arterial wall thickening may indicate imminent atheroma rupture.
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Affiliation(s)
- Canxing Xu
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Chun Yuan
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Department of Radiology, Vascular Imaging Laboratory, University of Washington, Seattle, Washington, USA
| | - Edward Stutzman
- D. E. Strandness, Jr. Vascular Laboratory, University of Washington Medical Center, Seattle, Washington, USA
| | - Gador Canton
- Department of Radiology, Vascular Imaging Laboratory, University of Washington, Seattle, Washington, USA
| | | | - Kirk W Beach
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Department of Radiology, Vascular Imaging Laboratory, University of Washington, Seattle, Washington, USA; Department of Surgery, University of Washington, Seattle, Washington, USA.
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Levy Nogueira M, Epelbaum S, Steyaert JM, Dubois B, Schwartz L. Mechanical stress models of Alzheimer's disease pathology. Alzheimers Dement 2015; 12:324-33. [PMID: 26718585 DOI: 10.1016/j.jalz.2015.10.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 09/11/2015] [Accepted: 10/15/2015] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Extracellular accumulation of amyloid-β protein and intracellular accumulation of tau in brain tissues have been described in animal models of Alzheimer's disease (AD) and mechanical stress-based diseases of different mechanisms, such as traumatic brain injury (TBI), arterial hypertension (HTN), and normal pressure hydrocephalus (NPH). METHODS We provide a brief overview of experimental models of TBI, HTN, and NPH showing features of tau-amyloid pathology, neuroinflammation, and neuronal loss. RESULTS "Alzheimer-like" hallmarks found in these mechanical stress-based models were compared with AD features found in transgenic models. DISCUSSION The goal of this review is, therefore, to build on current concepts of onset and progression of AD lesions. We point to the importance of accumulated mechanical stress in brain as an environmental and endogenous factor that pushes protein deposition and neuronal injury over the disease threshold. We further encourage the development of preventing strategies and drug screening based on mechanical stress models.
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Affiliation(s)
- Marcel Levy Nogueira
- Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Département de Neurologie, Hôpital de la Pitié-Salpêtrière, AP-HP, Paris, France; Institut des Neurosciences Translationnelles de Paris (IHU-A-ICM), Institut du Cerveau et de la Moelle Epinière (ICM), Paris, France; Laboratoire d'informatique (LIX), UMR 7161, Ecole Polytechnique, Université Paris-Saclay, Palaiseau, France.
| | - Stéphane Epelbaum
- Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Département de Neurologie, Hôpital de la Pitié-Salpêtrière, AP-HP, Paris, France; INSERM, CNRS, UMR-S975, Institut du Cerveau et de la Moelle Epinière (ICM), Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Hôpital de la Pitié-Salpêtrière, AP-HP, Paris, France
| | - Jean-Marc Steyaert
- Laboratoire d'informatique (LIX), UMR 7161, Ecole Polytechnique, Université Paris-Saclay, Palaiseau, France
| | - Bruno Dubois
- Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Département de Neurologie, Hôpital de la Pitié-Salpêtrière, AP-HP, Paris, France; Institut des Neurosciences Translationnelles de Paris (IHU-A-ICM), Institut du Cerveau et de la Moelle Epinière (ICM), Paris, France; INSERM, CNRS, UMR-S975, Institut du Cerveau et de la Moelle Epinière (ICM), Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Hôpital de la Pitié-Salpêtrière, AP-HP, Paris, France
| | - Laurent Schwartz
- Laboratoire d'informatique (LIX), UMR 7161, Ecole Polytechnique, Université Paris-Saclay, Palaiseau, France
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Levy Nogueira M, da Veiga Moreira J, Baronzio GF, Dubois B, Steyaert JM, Schwartz L. Mechanical Stress as the Common Denominator between Chronic Inflammation, Cancer, and Alzheimer's Disease. Front Oncol 2015; 5:197. [PMID: 26442209 PMCID: PMC4585184 DOI: 10.3389/fonc.2015.00197] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 08/24/2015] [Indexed: 11/13/2022] Open
Abstract
The pathogenesis of common diseases, such as Alzheimer's disease (AD) and cancer, are currently poorly understood. Inflammation is a common risk factor for cancer and AD. Recent data, provided by our group and from others, demonstrate that increased pressure and inflammation are synonymous. There is a continuous increase in pressure from inflammation to fibrosis and then cancer. This is in line with the numerous papers reporting high interstitial pressure in cancer. But most authors focus on the role of pressure in the lack of delivery of chemotherapy in the center of the tumor. Pressure may also be a key factor in carcinogenesis. Increased pressure is responsible for oncogene activation and cytokine secretion. Accumulation of mechanical stress plays a key role in the development of diseases of old age, such as cardiomyopathy, atherosclerosis, and osteoarthritis. Growing evidence suggest also a possible link between mechanical stress in the pathogenesis of AD. The aim of this review is to describe environmental and endogenous mechanical factors possibly playing a pivotal role in the mechanism of chronic inflammation, AD, and cancer.
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Affiliation(s)
- Marcel Levy Nogueira
- Département de Neurologie, Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Hôpital de la Pitié-Salpêtrière, AP-HP , Paris , France ; Institut des Neurosciences Translationnelles de Paris (IHU-A-ICM), Institut du Cerveau et de la Moelle Epinière (ICM) , Paris , France ; UMR 7161, Laboratoire d'informatique (LIX), Ecole Polytechnique, Université Paris-Saclay , Palaiseau , France
| | - Jorgelindo da Veiga Moreira
- UMR 7161, Laboratoire d'informatique (LIX), Ecole Polytechnique, Université Paris-Saclay , Palaiseau , France
| | | | - Bruno Dubois
- Département de Neurologie, Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Hôpital de la Pitié-Salpêtrière, AP-HP , Paris , France ; Institut des Neurosciences Translationnelles de Paris (IHU-A-ICM), Institut du Cerveau et de la Moelle Epinière (ICM) , Paris , France ; UMR-S975, CNRS, INSERM, Institut du Cerveau et de la Moelle Epinière (ICM) , Paris , France
| | - Jean-Marc Steyaert
- UMR 7161, Laboratoire d'informatique (LIX), Ecole Polytechnique, Université Paris-Saclay , Palaiseau , France
| | - Laurent Schwartz
- UMR 7161, Laboratoire d'informatique (LIX), Ecole Polytechnique, Université Paris-Saclay , Palaiseau , France
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Ultrasound measurements of brain tissue pulsatility correlate with the volume of MRI white-matter hyperintensity. J Cereb Blood Flow Metab 2014; 34:942-4. [PMID: 24714033 PMCID: PMC4050254 DOI: 10.1038/jcbfm.2014.58] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Revised: 01/12/2014] [Accepted: 02/22/2014] [Indexed: 11/08/2022]
Abstract
White-matter hyperintensity (WMH) is frequently seen in magnetic resonance imaging (MRI), but the complete physiopathology of WMH remains to be elucidated. In this study, we sought to determine whether there is an association between the maximum brain tissue displacement (maxBTD), as assessed by ultrasound, and the WMH, as observed by MRI. Nine healthy women aged 60 to 85 years underwent ultrasound and MRI assessments. We found a significant negative correlation between maxBTD and WMH (ρ=-0.86, P<0.001), suggesting a link between cerebral hypoperfusion and WMH.
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Certon D, Ternifi R, Boulme A, Legros M, Minonzio JG, Talmant M, Patat F, Remenieras JP. Low frequency cMUT technology: Application to measurement of brain movement and assessment of bone quality. Ing Rech Biomed 2013. [DOI: 10.1016/j.irbm.2013.01.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Abstract
All cells are influenced by mechanical forces. In the brain, force-generating and load-bearing proteins twist, turn, ratchet, flex, compress, expand and bend to mediate neuronal signalling and plasticity. Although the functions of mechanosensitive proteins have been thoroughly described in classical sensory systems, the effects of endogenous mechanical energy on cellular function in the brain have received less attention, and many working models in neuroscience do not currently integrate principles of cellular mechanics. An understanding of cellular-mechanical concepts is essential to allow the integration of mechanobiology into ongoing studies of brain structure and function.
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Desmidt T, Hachemi ME, Remenieras JP, Lecomte P, Ferreira-Maldent N, Patat F, Camus V. Ultrasound Brain Tissue Pulsatility is decreased in middle aged and elderly type 2 diabetic patients with depression. Psychiatry Res 2011; 193:63-4. [PMID: 21592742 DOI: 10.1016/j.pscychresns.2011.01.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2010] [Revised: 11/29/2010] [Accepted: 01/06/2011] [Indexed: 11/28/2022]
Abstract
We used Tissue Pulsatility Imaging (TPI) to compare the Brain Tissue Pulsatility (BTP) in depressed (n=11) and non-depressed (n=13) type-2 diabetic non-demented patients aged 50 years and older. Both maximum and mean BTP were significantly decreased in depressed diabetic subjects compared to non-depressed diabetic subjects.
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Keller CJ, Cash SS, Narayanan S, Wang C, Kuzniecky R, Carlson C, Devinsky O, Thesen T, Doyle W, Sassaroli A, Boas DA, Ulbert I, Halgren E. Intracranial microprobe for evaluating neuro-hemodynamic coupling in unanesthetized human neocortex. J Neurosci Methods 2009; 179:208-18. [PMID: 19428529 DOI: 10.1016/j.jneumeth.2009.01.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Revised: 01/27/2009] [Accepted: 01/29/2009] [Indexed: 10/21/2022]
Abstract
Measurement of the blood-oxygen-level dependent (BOLD) response with fMRI has revolutionized cognitive neuroscience and is increasingly important in clinical care. The BOLD response reflects changes in deoxy-hemoglobin concentration, blood volume, and blood flow. These hemodynamic changes ultimately result from neuronal firing and synaptic activity, but the linkage between these domains is complex, poorly understood, and may differ across species, cortical areas, diseases, and cognitive states. We describe here a technique that can measure neural and hemodynamic changes simultaneously from cortical microdomains in waking humans. We utilize a "laminar optode," a linear array of microelectrodes for electrophysiological measures paired with a micro-optical device for hemodynamic measurements. Optical measurements include laser Doppler to estimate cerebral blood flow as well as point spectroscopy to estimate oxy- and deoxy-hemoglobin concentrations. The microelectrode array records local field potential gradients (PG) and multi-unit activity (MUA) at 24 locations spanning the cortical depth, permitting estimation of population trans-membrane current flows (Current Source Density, CSD) and population cell firing in each cortical lamina. Comparison of the laminar CSD/MUA profile with the origins and terminations of cortical circuits allows activity in specific neuronal circuits to be inferred and then directly compared to hemodynamics. Access is obtained in epileptic patients during diagnostic evaluation for surgical therapy. Validation tests with relatively well-understood manipulations (EKG, breath-holding, cortical electrical stimulation) demonstrate the expected responses. This device can provide a new and robust means for obtaining detailed, quantitative data for defining neurovascular coupling in awake humans.
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Affiliation(s)
- Corey J Keller
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA.
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Kucewicz JC, Dunmire B, Giardino ND, Leotta DF, Paun M, Dager SR, Beach KW. Tissue pulsatility imaging of cerebral vasoreactivity during hyperventilation. ULTRASOUND IN MEDICINE & BIOLOGY 2008; 34:1200-1208. [PMID: 18336991 PMCID: PMC2582389 DOI: 10.1016/j.ultrasmedbio.2008.01.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2007] [Revised: 11/02/2007] [Accepted: 01/02/2008] [Indexed: 05/26/2023]
Abstract
Tissue pulsatility imaging (TPI) is an ultrasonic technique that is being developed at the University of Washington to measure tissue displacement or strain as a result of blood flow over the cardiac and respiratory cycles. This technique is based in principle on plethysmography, an older nonultrasound technology for measuring expansion of a whole limb or body part due to perfusion. TPI adapts tissue Doppler signal processing methods to measure the "plethysmographic" signal from hundreds or thousands of sample volumes in an ultrasound image plane. This paper presents a feasibility study to determine if TPI can be used to assess cerebral vasoreactivity. Ultrasound data were collected transcranially through the temporal acoustic window from four subjects before, during and after voluntary hyperventilation. In each subject, decreases in tissue pulsatility during hyperventilation were observed that were statistically correlated with the subject's end-tidal CO2 measurements. (
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Affiliation(s)
- John C Kucewicz
- Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, Seattle, WA, USA.
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