1
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Toader AE, Fukuda M, Vazquez AL. Evaluation of calibrated and uncalibrated optical imaging approaches for relative cerebral oxygen metabolism measurements in awake mice. Physiol Meas 2024; 45:045007. [PMID: 38569522 DOI: 10.1088/1361-6579/ad3a2d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 04/03/2024] [Indexed: 04/05/2024]
Abstract
Objective. The continuous delivery of oxygen is critical to sustain brain function, and therefore, measuring brain oxygen consumption can provide vital physiological insight. In this work, we examine the impact of calibration and cerebral blood flow (CBF) measurements on the computation of the relative changes in the cerebral metabolic rate of oxygen consumption (rCMRO2) from hemoglobin-sensitive intrinsic optical imaging data. Using these data, we calculate rCMRO2, and calibrate the model using an isometabolic stimulus.Approach. We used awake head-fixed rodents to obtain hemoglobin-sensitive optical imaging data to test different calibrated and uncalibrated rCMRO2models. Hypercapnia was used for calibration and whisker stimulation was used to test the impact of calibration.Main results. We found that typical uncalibrated models can provide reasonable estimates of rCMRO2with differences as small as 7%-9% compared to their calibrated models. However, calibrated models showed lower variability and less dependence on baseline hemoglobin concentrations. Lastly, we found that supplying the model with measurements of CBF significantly reduced error and variability in rCMRO2change calculations.Significance. The effect of calibration on rCMRO2calculations remains understudied, and we systematically evaluated different rCMRO2calculation scenarios that consider including different measurement combinations. This study provides a quantitative comparison of these scenarios to evaluate trade-offs that can be vital to the design of blood oxygenation sensitive imaging experiments for rCMRO2calculation.
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Affiliation(s)
- A E Toader
- Departments of Radiology, University of Pittsburgh, Pittsburgh PA 15217, United States of America
| | - M Fukuda
- Departments of Radiology, University of Pittsburgh, Pittsburgh PA 15217, United States of America
| | - A L Vazquez
- Departments of Radiology, University of Pittsburgh, Pittsburgh PA 15217, United States of America
- Bioengineering, University of Pittsburgh, Pittsburgh PA 15217, United States of America
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2
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Amra LN, Mächler P, Fomin-Thunemann N, Kılıç K, Saisan P, Devor A, Thunemann M. Tissue Oxygen Depth Explorer: an interactive database for microscopic oxygen imaging data. Front Neuroinform 2023; 17:1278787. [PMID: 38088985 PMCID: PMC10711099 DOI: 10.3389/fninf.2023.1278787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 11/07/2023] [Indexed: 02/01/2024] Open
Affiliation(s)
- Layth N. Amra
- Department of Biomedical Engineering, Boston University, Boston, MA, United States
| | - Philipp Mächler
- Department of Physics, University of California, San Diego, La Jolla, CA, United States
| | | | - Kıvılcım Kılıç
- Department of Biomedical Engineering, Boston University, Boston, MA, United States
| | - Payam Saisan
- Department of Radiology, University of California, San Diego, La Jolla, CA, United States
| | - Anna Devor
- Department of Biomedical Engineering, Boston University, Boston, MA, United States
- Harvard Medical School, Martinos Center for Biomedical Imaging, MGH, Charlestown, MA, United States
| | - Martin Thunemann
- Department of Biomedical Engineering, Boston University, Boston, MA, United States
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3
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Ito H, Ibaraki M, Yamakuni R, Hakozaki M, Ukon N, Ishii S, Fukushima K, Kubo H, Takahashi K. Oxygen extraction fraction is not uniform in human brain: a positron emission tomography study. J Physiol Sci 2023; 73:25. [PMID: 37828449 DOI: 10.1186/s12576-023-00880-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 09/28/2023] [Indexed: 10/14/2023]
Abstract
The regional differences in cerebral oxygen extraction fraction (OEF) in brain were investigated using positron emission tomography (PET) in detail with consideration of systemic errors in PET measurement estimated by simulation studies. The cerebral blood flow (CBF), cerebral blood volume (CBV), OEF, and cerebral metabolic rate of oxygen (CMRO2) were measured on healthy men by PET with 15O-labeled gases. The OEF values in the pons and the parahippocampal gyrus were significantly smaller than in the other brain regions. The OEF value in the lateral side of the occipital cortex was largest among the cerebral cortical regions. Simulation studies have revealed that errors in OEF caused by regional differences in the distribution volume of 15O-labeled water, as well as errors in OEF caused by a mixture of gray and white matter, must be negligible. The regional differences in OEF in brain must exist which might be related to physiological meanings.Article title: Kindly check and confirm the edit made in the article title.I have checked the article title and it is OK as is. Trial registration: The UMIN clinical trial number: UMIN000033382, https://www.umin.ac.jp/ctr/index.htm.
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Affiliation(s)
- Hiroshi Ito
- Department of Radiology and Nuclear Medicine, Fukushima Medical University, 1 Hikariga-Oka, Fukushima, 960-1295, Japan.
- Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan.
| | - Masanobu Ibaraki
- Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain and Blood Vessels, 6-10 Senshu-Kubota-Machi, Akita, 010-0874, Japan.
| | - Ryo Yamakuni
- Department of Radiology and Nuclear Medicine, Fukushima Medical University, 1 Hikariga-Oka, Fukushima, 960-1295, Japan
| | - Motoharu Hakozaki
- Department of Radiology and Nuclear Medicine, Fukushima Medical University, 1 Hikariga-Oka, Fukushima, 960-1295, Japan
| | - Naoyuki Ukon
- Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan
| | - Shiro Ishii
- Department of Radiology and Nuclear Medicine, Fukushima Medical University, 1 Hikariga-Oka, Fukushima, 960-1295, Japan
| | - Kenji Fukushima
- Department of Radiology and Nuclear Medicine, Fukushima Medical University, 1 Hikariga-Oka, Fukushima, 960-1295, Japan
| | - Hitoshi Kubo
- School of Medical Sciences, Fukushima Medical University, Fukushima, Japan
| | - Kazuhiro Takahashi
- Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan
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4
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Wood TC, Cash D, MacNicol E, Simmons C, Kim E, Lythgoe DJ, Zelaya F, Turkheimer F. Non-Invasive measurement of the cerebral metabolic rate of oxygen using MRI in rodents. Wellcome Open Res 2022; 6:109. [PMID: 36081865 PMCID: PMC9428501 DOI: 10.12688/wellcomeopenres.16734.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/08/2022] [Indexed: 08/17/2023] Open
Abstract
Malfunctions of oxygen metabolism are suspected to play a key role in a number of neurological and psychiatric disorders, but this hypothesis cannot be properly investigated without an in-vivo non-invasive measurement of brain oxygen consumption. We present a new way to measure the Cerebral Metabolic Rate of Oxygen (CMRO 2) by combining two existing magnetic resonance imaging techniques, namely arterial spin-labelling and oxygen extraction fraction mapping. This method was validated by imaging rats under different anaesthetic regimes and was strongly correlated to glucose consumption measured by autoradiography.
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Affiliation(s)
- Tobias C Wood
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, SE5 8AF, UK
| | - Diana Cash
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, SE5 8AF, UK
| | - Eilidh MacNicol
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, SE5 8AF, UK
| | - Camilla Simmons
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, SE5 8AF, UK
| | - Eugene Kim
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, SE5 8AF, UK
| | - David J Lythgoe
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, SE5 8AF, UK
| | - Fernando Zelaya
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, SE5 8AF, UK
| | - Federico Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, SE5 8AF, UK
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5
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Xu M, Bo B, Pei M, Chen Y, Shu CY, Qin Q, Hirschler L, Warnking JM, Barbier EL, Wei Z, Lu H, Herman P, Hyder F, Liu ZJ, Liang Z, Thompson GJ. High-resolution relaxometry-based calibrated fMRI in murine brain: Metabolic differences between awake and anesthetized states. J Cereb Blood Flow Metab 2022; 42:811-825. [PMID: 34910894 PMCID: PMC9014688 DOI: 10.1177/0271678x211062279] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Functional magnetic resonance imaging (fMRI) techniques using the blood-oxygen level-dependent (BOLD) signal have shown great potential as clinical biomarkers of disease. Thus, using these techniques in preclinical rodent models is an urgent need. Calibrated fMRI is a promising technique that can provide high-resolution mapping of cerebral oxygen metabolism (CMRO2). However, calibrated fMRI is difficult to use in rodent models for several reasons: rodents are anesthetized, stimulation-induced changes are small, and gas challenges induce noisy CMRO2 predictions. We used, in mice, a relaxometry-based calibrated fMRI method which uses cerebral blood flow (CBF) and the BOLD-sensitive magnetic relaxation component, R2', the same parameter derived in the deoxyhemoglobin-dilution model of calibrated fMRI. This method does not use any gas challenges, which we tested on mice in both awake and anesthetized states. As anesthesia induces a whole-brain change, our protocol allowed us to overcome the former limitations of rodent studies using calibrated fMRI. We revealed 1.5-2 times higher CMRO2, dependent upon brain region, in the awake state versus the anesthetized state. Our results agree with alternative measurements of whole-brain CMRO2 in the same mice and previous human anesthesia studies. The use of calibrated fMRI in rodents has much potential for preclinical fMRI.
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Affiliation(s)
- Mengyang Xu
- iHuman Institute, ShanghaiTech University, Shanghai, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China.,Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Binshi Bo
- CAS Center for Excellence in Brain Sciences and Intelligence Technology, Institute of Neuroscience, Chinese Academy of Sciences, Shanghai, China
| | - Mengchao Pei
- CAS Center for Excellence in Brain Sciences and Intelligence Technology, Institute of Neuroscience, Chinese Academy of Sciences, Shanghai, China
| | - Yuyan Chen
- CAS Center for Excellence in Brain Sciences and Intelligence Technology, Institute of Neuroscience, Chinese Academy of Sciences, Shanghai, China
| | - Christina Y Shu
- Biomedical Engineering, Yale University, New Haven, CT, USA.,Magnetic Resonance Research Center (MRRC), Yale University, New Haven, CT, USA
| | - Qikai Qin
- iHuman Institute, ShanghaiTech University, Shanghai, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China.,Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China
| | - Lydiane Hirschler
- Grenoble Institut des Neurosciences, Inserm, Univ. Grenoble Alpes, Grenoble, France.,C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jan M Warnking
- Grenoble Institut des Neurosciences, Inserm, Univ. Grenoble Alpes, Grenoble, France
| | - Emmanuel L Barbier
- Grenoble Institut des Neurosciences, Inserm, Univ. Grenoble Alpes, Grenoble, France
| | - Zhiliang Wei
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
| | - Hanzhang Lu
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
| | - Peter Herman
- Magnetic Resonance Research Center (MRRC), Yale University, New Haven, CT, USA.,Quantitative Neuroscience with Magnetic Resonance (QNMR) Core Center, Yale University, New Haven, CT, USA.,Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA
| | - Fahmeed Hyder
- Biomedical Engineering, Yale University, New Haven, CT, USA.,Magnetic Resonance Research Center (MRRC), Yale University, New Haven, CT, USA.,Quantitative Neuroscience with Magnetic Resonance (QNMR) Core Center, Yale University, New Haven, CT, USA.,Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA
| | - Zhi-Jie Liu
- iHuman Institute, ShanghaiTech University, Shanghai, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China.,Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China
| | - Zhifeng Liang
- CAS Center for Excellence in Brain Sciences and Intelligence Technology, Institute of Neuroscience, Chinese Academy of Sciences, Shanghai, China
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6
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van Zijl PCM, Brindle K, Lu H, Barker PB, Edden R, Yadav N, Knutsson L. Hyperpolarized MRI, functional MRI, MR spectroscopy and CEST to provide metabolic information in vivo. Curr Opin Chem Biol 2021; 63:209-218. [PMID: 34298353 PMCID: PMC8384704 DOI: 10.1016/j.cbpa.2021.06.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 06/12/2021] [Accepted: 06/15/2021] [Indexed: 12/13/2022]
Abstract
Access to metabolic information in vivo using magnetic resonance (MR) technologies has generally been the niche of MR spectroscopy (MRS) and spectroscopic imaging (MRSI). Metabolic fluxes can be studied using the infusion of substrates labeled with magnetic isotopes, with the use of hyperpolarization especially powerful. Unfortunately, these promising methods are not yet accepted clinically, where fast, simple, and reliable measurement and diagnosis are key. Recent advances in functional MRI and chemical exchange saturation transfer (CEST) MRI allow the use of water imaging to study oxygen metabolism and tissue metabolite levels. These, together with the use of novel data analysis approaches such as machine learning for all of these metabolic MR approaches, are increasing the likelihood of their clinical translation.
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Affiliation(s)
- Peter C M van Zijl
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA.
| | - Kevin Brindle
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK
| | - Hanzhang Lu
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
| | - Peter B Barker
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
| | - Richard Edden
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
| | - Nirbhay Yadav
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
| | - Linda Knutsson
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Medical Radiation Physics, Lund University, Lund, Sweden
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7
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Germuska M, Chandler HL, Okell T, Fasano F, Tomassini V, Murphy K, Wise RG. Corrigendum: A Frequency-Domain Machine Learning Method for Dual-Calibrated fMRI Mapping of Oxygen Extraction Fraction (OEF) and Cerebral Metabolic Rate of Oxygen Consumption (CMRO 2). Front Artif Intell 2021; 4:614245. [PMID: 34327328 PMCID: PMC8313422 DOI: 10.3389/frai.2021.614245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 06/29/2021] [Indexed: 11/13/2022] Open
Affiliation(s)
- Michael Germuska
- Cardiff University Brain Research Imaging Centre (CUBRIC), Department of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Hannah Louise Chandler
- Cardiff University Brain Research Imaging Centre (CUBRIC), Department of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Thomas Okell
- FMRIB, Nuffield Department of Clinical Neurosciences, Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, United Kingdom
| | | | - Valentina Tomassini
- Cardiff University Brain Research Imaging Centre (CUBRIC), Department of Psychology, Cardiff University, Cardiff, United Kingdom.,Division of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine, Cardiff, United Kingdom.,Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio University" of Chieti-Pescara, Chieti, Italy
| | - Kevin Murphy
- Cardiff University Brain Research Imaging Centre (CUBRIC), Department of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Richard G Wise
- Cardiff University Brain Research Imaging Centre (CUBRIC), Department of Psychology, Cardiff University, Cardiff, United Kingdom.,Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio University" of Chieti-Pescara, Chieti, Italy.,Institute for Advanced Biomedical Technologies, "G. D'Annunzio University" of Chieti-Pescara, Chieti, Italy
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8
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Mächler P, Broggini T, Mateo C, Thunemann M, Fomin-Thunemann N, Doran PR, Sencan I, Kilic K, Desjardins M, Uhlirova H, Yaseen MA, Boas DA, Linninger AA, Vergassola M, Yu X, Lewis LD, Polimeni JR, Rosen BR, Sakadžić S, Buxton RB, Lauritzen M, Kleinfeld D, Devor A. A Suite of Neurophotonic Tools to Underpin the Contribution of Internal Brain States in fMRI. Curr Opin Biomed Eng 2021; 18:100273. [PMID: 33959688 PMCID: PMC8095678 DOI: 10.1016/j.cobme.2021.100273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Recent developments in optical microscopy, applicable for large-scale and longitudinal imaging of cortical activity in behaving animals, open unprecedented opportunities to gain a deeper understanding of neurovascular and neurometabolic coupling during different brain states. Future studies will leverage these tools to deliver foundational knowledge about brain state-dependent regulation of cerebral blood flow and metabolism as well as regulation as a function of brain maturation and aging. This knowledge is of critical importance to interpret hemodynamic signals observed with functional magnetic resonance imaging (fMRI).
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Affiliation(s)
- Philipp Mächler
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | - Thomas Broggini
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | - Celine Mateo
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | - Martin Thunemann
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | | | - Patrick R. Doran
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Ikbal Sencan
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Kivilcim Kilic
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Michèle Desjardins
- Département de Physique, de Génie Physique et d’Optique, Université Laval, Québec, QC G1V 0A6, Canada
| | - Hana Uhlirova
- Institute of Scientific Instruments of the Czech Academy of Science, Brno, Czech Republic
| | - Mohammad A. Yaseen
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA 02129, USA
- Department of Bioengineering, Northeastern University, Boston, MA 02115, USA
| | - David A. Boas
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Andreas A. Linninger
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Massimo Vergassola
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
- Département de Physique de l’Ecole Normale Supérieure, 75005 Paris, France
| | - Xin Yu
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Laura D. Lewis
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Jonathan R. Polimeni
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Bruce R. Rosen
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Sava Sakadžić
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Richard B. Buxton
- Department of Radiology, University of California San Diego, La Jolla, CA 92037, USA
| | - Martin Lauritzen
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen N 2200, Denmark
- Department of Clinical Neurophysiology, Glostrup Hospital, Glostrup 2600, Denmark
| | - David Kleinfeld
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
- Section on Neurobiology, University of California San Diego, La Jolla, CA 92093, USA
| | - Anna Devor
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA 02129, USA
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9
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Qi Y, He J. Neurophysiologic Profiling of At-Risk Low and Very Low Birth-Weight Infants Using Magnetic Resonance Imaging. Front Physiol 2021; 12:638868. [PMID: 33833688 PMCID: PMC8021729 DOI: 10.3389/fphys.2021.638868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 03/02/2021] [Indexed: 11/13/2022] Open
Abstract
Low birth-weight (LBW) and very low birth-weight (VLBW) newborns have increased risks of brain injuries, growth failure, motor difficulties, developmental coordination disorders or delay, and adult-onset vascular diseases. However, relatively little is known of the neurobiologic underpinnings. To clarify the pathophysiologic vulnerabilities of such neonates, we applied several advanced techniques for assessing brain physiology, namely T2-relaxation-under-spin-tagging (TRUST) magnetic resonance imaging (MRI) and phase-contrast (PC) MRI. This enabled quantification of oxygen extraction fraction (OEF), global cerebral blood flow (CBF), and cerebral metabolic rate of oxygen (CMRO2). A total of 50 neonates (LBW-VLBW, 41; term controls, 9) participated in this study. LBW-VLBW neonates were further stratified as those with (LBW-VLBW-a, 24) and without (LBW-VLBW-n, 17) structural MRI (sMRI) abnormalities. TRUST and PC MRI studies were undertaken to determine OEF, CBF, and CMRO2. Ultimately, CMRO2 proved significantly lower (p = 0.01) in LBW-VLBW (vs term) neonates, both LBW-VLBW-a and LBW-VLBW-n subsets showing significantly greater physiologic deficits than term controls (p = 0.03 and p = 0.04, respectively). CMRO2 and CBF in LBW-VLBW-a and LBW-VLBW-n subsets did not differ significantly (p > 0.05), although OEF showed a tendency to diverge (p = 0.15). However, OEF values in the LBW-VLBW-n subset differed significantly from those of term controls (p = 0.02). Compared with brain volume or body weight, these physiologic parameters yield higher area-under-the-curve (AUC) values for distinguishing neonates of the LBW-VLBW-a subset. The latter displayed distinct cerebral metabolic and hemodynamic, whereas changes were marginal in the LBW-VLBW-n subset (i.e., higher OEF and lower CBF and CMRO2) by comparison. Physiologic imaging may therefore be useful in identifying LBW-VLBW newborns at high risk of irreversible brain damage.
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Affiliation(s)
- Ying Qi
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Jingni He
- Department of Surgery, Shengjing Hospital of China Medical University, Shenyang, China
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10
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Ito H, Kubo H, Takahashi K, Nishijima KI, Ukon N, Nemoto A, Sugawara S, Yamakuni R, Ibaraki M, Ishii S. Integrated PET/MRI scanner with oxygen-15 labeled gases for quantification of cerebral blood flow, cerebral blood volume, cerebral oxygen extraction fraction and cerebral metabolic rate of oxygen. Ann Nucl Med 2021; 35:421-428. [PMID: 33502738 DOI: 10.1007/s12149-021-01578-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Accepted: 01/04/2021] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Measurement of cerebral blood flow (CBF), cerebral blood volume (CBV), cerebral oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO2) by PET with oxygen-15 labeled gases is useful for diagnosis and treatment planning in cases of chronic occlusive cerebrovascular disease. In the present study, CBF, CBV, OEF and CMRO2 were measured using the integrated design of PET/MRI scanner system. This is a first attempt to measure cerebral perfusion and oxygen metabolism using PET/MRI with oxygen-15 labeled gases. METHODS PET/MRI measurements with the steady-state method of oxygen-15 labeled gases, carbon monoxide (C15O), oxygen (15O2), and carbon dioxide (C15O2) were performed on nine healthy men. Two kinds of attenuation correction for PET were performed using MRI with Dixon sequence (DIXON) and Dixon sequence with model-based bone segmentation (DIXONbone). A real-time motion correction of PET images was also performed using simultaneously measured MR images to detect head motion. RESULTS Mean and SD values of CBF, CBV, OEF, and CMRO2 in the cerebral cortices with attenuation correction by DIXON were 31 ± 4 mL/100 mL/min, 2.7 ± 0.2 mL/mL, 0.40 ± 0.07, and 2.5 ± 0.3 mL/100 mL/min without real-time motion correction, and 33 ± 4 mL/100 mL/min, 2.7 ± 0.2 mL/mL, 0.40 ± 0.07, and 2.6 ± 0.3 mL/100 mL/min with real-time motion correction, respectively. Values with of CBF, CBV, OEF, and CMRO2 with attenuation correction by DIXONbone were 35 ± 5 mL/100 mL/min, 2.8 ± 0.2 mL/mL, 0.40 ± 0.07, and 2.8 ± 0.3 mL/100 mL/min without real-time motion correction, and 38 ± 5 mL/100 mL/min, 2.8 ± 0.2 mL/mL, 0.40 ± 0.07, and 3.0 ± 0.4 mL/100 mL/min with real-time motion correction, respectively. CONCLUSIONS Using PET/MRI with oxygen-15 labeled gases, CBF, CBV, OEF, and CMRO2 could be measured. Values of CBF, CBV, and CMRO2 measured with attenuation correction by DIXON were significantly lower than those measured with correction by DIXONbone. One of the reasons for this is that attenuation correction of DIXON does not take into consideration of the photon absorption by bone. OEF values, corresponding to ratios of CMRO2 to CBF, were not affected by attenuation correction methods. Values of CBF and CMRO2 with a real-time motion correction were significantly higher than those without correction. Using PET/MRI with adequate corrections, similar values of CBF, CBV, OEF, and CMRO2 as PET alone scanner system reported previously were obtained. TRAIL REGISTRATION The UMIN clinical trial number: UMIN000033382.
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Affiliation(s)
- Hiroshi Ito
- Department of Radiology and Nuclear Medicine, Fukushima Medical University, 1 Hikariga-oka, Fukushima, 960-1295, Japan.
- Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan.
| | - Hitoshi Kubo
- Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan
| | - Kazuhiro Takahashi
- Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan
| | - Ken-Ichi Nishijima
- Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan
| | - Naoyuki Ukon
- Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan
| | - Ayaka Nemoto
- Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan
| | - Shigeyasu Sugawara
- Department of Radiology and Nuclear Medicine, Fukushima Medical University, 1 Hikariga-oka, Fukushima, 960-1295, Japan
- Advanced Clinical Research Center, Fukushima Medical University, Fukushima, Japan
| | - Ryo Yamakuni
- Department of Radiology and Nuclear Medicine, Fukushima Medical University, 1 Hikariga-oka, Fukushima, 960-1295, Japan
| | - Masanobu Ibaraki
- Department of Radiology and Nuclear Medicine, Akita Research Institute of Brain and Blood Vessels, Akita, Japan
| | - Shiro Ishii
- Department of Radiology and Nuclear Medicine, Fukushima Medical University, 1 Hikariga-oka, Fukushima, 960-1295, Japan
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11
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Cho J, Ma Y, Spincemaille P, Pike GB, Wang Y. Cerebral oxygen extraction fraction: Comparison of dual-gas challenge calibrated BOLD with CBF and challenge-free gradient echo QSM+qBOLD. Magn Reson Med 2020; 85:953-961. [PMID: 32783233 DOI: 10.1002/mrm.28447] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 06/23/2020] [Accepted: 07/06/2020] [Indexed: 12/12/2022]
Abstract
PURPOSE To compare cortical gray matter oxygen extraction fraction (OEF) estimated from 2 MRI methods: (1) the quantitative susceptibility mapping (QSM) plus quantitative blood oxygen level dependent imaging (qBOLD) (QSM+qBOLD or QQ), and (2) the dual-gas calibrated-BOLD (DGCB) in healthy subjects; and to investigate the validity of iso-cerebral metabolic rate of oxygen consumption assumption during hypercapnia using QQ. METHODS In 10 healthy subjects, 3 tesla MRI including a multi-echo gradient echo sequence at baseline and hypercapnia for QQ, as well as an EPI dual-echo pseudo-continuous arterial spin labeling for DGCB, were performed under a hypercapnic and a hyperoxic condition. OEFs from QQ and DGCB were compared using region of interest analysis and paired t test. For QQ, cerebral metabolic rate of oxygen consumption = cerebral blood flow*OEF*arterial oxygen content was generated for both baseline and hypercapnia, which were compared. RESULTS Average OEF in cortical gray matter across 10 subjects from QQ versus DGCB was 35.5 ± 6.7% versus 38.0 ± 9.1% (P = .49) at baseline and 20.7 ± 4.4% versus 28.4 ± 7.6% (P = .02) in hypercapnia: OEF in cortical gray matter was significantly reduced as measured in QQ (P < .01) and in DGCB (P < .01). Cerebral metabolic rate of oxygen consumption (in μmol O2 /min/100 g) was 168.2 ± 54.1 at baseline from DGCB and was 153.1 ± 33.8 at baseline and 126.4 ± 34.2 (P < .01) in hypercapnia from QQ. CONCLUSION The differences in OEF obtained from QQ and DGCB are small and nonsignificant at baseline but are statistically significant during hypercapnia. In addition, QQ shows a cerebral metabolic rate of oxygen consumption decrease (17.4%) during hypercapnia.
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Affiliation(s)
- Junghun Cho
- Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - Yuhan Ma
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Pascal Spincemaille
- Department of Radiology, Weill Cornell Medical College, New York, New York, USA
| | - Gilbert Bruce Pike
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada.,Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Yi Wang
- Department of Radiology, Weill Cornell Medical College, New York, New York, USA.,Department of Biomedical Engineering, Cornell University, Ithaca, New York, USA
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12
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Kumar VHS, Gugino S, Nielsen L, Chandrasekharan P, Koenigsknecht C, Helman J, Lakshminrusimha S. Protection from systemic pyruvate at resuscitation in newborn lambs with asphyxial cardiac arrest. Physiol Rep 2020; 8:e14472. [PMID: 32596995 PMCID: PMC7322497 DOI: 10.14814/phy2.14472] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 05/04/2020] [Accepted: 05/10/2020] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Infants with hypoxic-ischemic injury often require cardiopulmonary resuscitation. Mitochondrial failure to generate adenosine triphosphate (ATP) during hypoxic-ischemic reperfusion injury contributes to cellular damage. Current postnatal strategies to improve outcome in hypoxic-ischemic injury need sophisticated equipment to perform servo-controlled cooling. Administration of intravenous pyruvate, an antioxidant with favorable effects on mitochondrial bioenergetics, is a simple intervention that can have a global impact. We hypothesize that the administration of pyruvate following the return of spontaneous circulation (ROSC) would improve cardiac function, systemic hemodynamics, and oxygen utilization in the brain in newborn lambs with cardiac arrest (CA). METHODS Term lambs were instrumented, delivered by C-section and asphyxia induced by umbilical cord occlusion along with clamping of the endotracheal tube until asystole; Lambs resuscitated following 5 min of CA; upon ROSC, lambs were randomized to receive pyruvate or saline infusion over 90 min and ventilated for 150 min postinfusion. Pulmonary and systemic hemodynamics and arterial gases monitored. We measured plasma pyruvate, tissue lactate, and ATP levels (heart and brain) in both groups. RESULTS Time to ROSC was not different between the two groups. Systolic and diastolic blood pressures, stroke volume, arterial oxygen content, and cerebral oxygen delivery were similar between the two groups. The cerebral metabolic rate of oxygen was higher following pyruvate infusion; higher oxygen consumption in the brain was associated with lower plasma levels but higher brain ATP levels compared to the saline group. CONCLUSIONS Pyruvate promotes energy generation accompanied by efficient oxygen utilization in the brain and may facilitate additional neuroprotection in the presence of hypoxic-ischemic injury.
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Affiliation(s)
| | - Sylvia Gugino
- Department of PediatricsUniversity at BuffaloBuffaloNYUSA
| | - Lori Nielsen
- Department of PediatricsUniversity at BuffaloBuffaloNYUSA
| | | | | | - Justin Helman
- Department of PediatricsUniversity at BuffaloBuffaloNYUSA
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13
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Germuska M, Chandler H, Okell T, Fasano F, Tomassini V, Murphy K, Wise R. A frequency-domain machine learning method for dual-calibrated fMRI mapping of oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen consumption (CMRO 2). Front Artif Intell 2020; 3. [PMID: 32885165 PMCID: PMC7116003 DOI: 10.3389/frai.2020.00012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Magnetic resonance imaging (MRI) offers the possibility to non-invasively map the brain's metabolic oxygen consumption (CMRO2), which is essential for understanding and monitoring neural function in both health and disease. However, in depth study of oxygen metabolism with MRI has so far been hindered by the lack of robust methods. One MRI method of mapping CMRO2 is based on the simultaneous acquisition of cerebral blood flow (CBF) and blood oxygen level dependent (BOLD) weighted images during respiratory modulation of both oxygen and carbon dioxide. Although this dual-calibrated methodology has shown promise in the research setting, current analysis methods are unstable in the presence of noise and/or are computationally demanding. In this paper, we present a machine learning implementation for the multi-parametric assessment of dual-calibrated fMRI data. The proposed method aims to address the issues of stability, accuracy, and computational overhead, removing significant barriers to the investigation of oxygen metabolism with MRI. The method utilizes a time-frequency transformation of the acquired perfusion and BOLD-weighted data, from which appropriate feature vectors are selected for training of machine learning regressors. The implemented machine learning methods are chosen for their robustness to noise and their ability to map complex non-linear relationships (such as those that exist between BOLD signal weighting and blood oxygenation). An extremely randomized trees (ET) regressor is used to estimate resting blood flow and a multi-layer perceptron (MLP) is used to estimate CMRO2 and the oxygen extraction fraction (OEF). Synthetic data with additive noise are used to train the regressors, with data simulated to cover a wide range of physiologically plausible parameters. The performance of the implemented analysis method is compared to published methods both in simulation and with in-vivo data (n = 30). The proposed method is demonstrated to significantly reduce computation time, error, and proportional bias in both CMRO2 and OEF estimates. The introduction of the proposed analysis pipeline has the potential to not only increase the detectability of metabolic difference between groups of subjects, but may also allow for single subject examinations within a clinical context.
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Affiliation(s)
- Michael Germuska
- CUBRIC, Department of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Hannah Chandler
- CUBRIC, Department of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Thomas Okell
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, United Kingdom
| | | | - Valentina Tomassini
- CUBRIC, Department of Psychology, Cardiff University, Cardiff, United Kingdom.,Division of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine, Cardiff, United Kingdom.,Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio University" of Chieti-Pescara, 66100, Chieti, Italy
| | - Kevin Murphy
- CUBRIC, Department of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Richard Wise
- CUBRIC, Department of Psychology, Cardiff University, Cardiff, United Kingdom.,Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio University" of Chieti-Pescara, 66100, Chieti, Italy.,Institute for Advanced Biomedical Technologies, "G. D'Annunzio University" of Chieti-Pescara, 66100, Chieti, Italy
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14
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Li W, Xu X, Liu P, Strouse JJ, Casella JF, Lu H, van Zijl PCM, Qin Q. Quantification of whole-brain oxygenation extraction fraction and cerebral metabolic rate of oxygen consumption in adults with sickle cell anemia using individual T 2 -based oxygenation calibrations. Magn Reson Med 2019; 83:1066-1080. [PMID: 31483528 DOI: 10.1002/mrm.27972] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 07/18/2019] [Accepted: 08/05/2019] [Indexed: 12/23/2022]
Abstract
PURPOSE To evaluate different T2 -oxygenation calibrations for estimating venous oxygenation in people with sickle cell anemia (SCA). METHODS Blood T2 values were measured at 3 T in the internal jugular veins of 12 healthy volunteers and 11 SCA participants with no history of stroke, recent transfusion, or renal impairment. T2 -oxygenation relationships of both sickled and normal blood samples were calibrated individually and compared with values generated from published models. After converting venous T2 values to venous oxygenation, whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen were calculated. RESULTS Sickle blood samples' oxygenation values calculated from our individual calibrations agreed well with measurements using a blood analyzer, whereas previous T2 calibrations based on normal blood samples showed 13%-19% underestimation. Meanwhile, oxygenation values calculated from previous grouped T2 calibration for sickle blood agreed well with experimental measurement on averaged values, but showed up to 20% variation for several individual samples. Using individual T2 calibrations, the whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen of SCA participants were 0.38 ± 0.08 and 172 ± 42 µmol/min/100 g, respectively, which were comparable to those values measured on healthy volunteers. CONCLUSION Our results confirm that sickle blood T2 values not only depend on the hematocrit and oxygenation values, but also on other hematological factors. The individual T2 calibrations minimized the effect of heterogeneity of sickle blood between different SCA populations and improved the accuracy of T2 -based oximetry. The measured oxygen extraction fraction and cerebral metabolic rate of oxygen of this group of SCA participants were found to not differ significantly from those of healthy individuals.
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Affiliation(s)
- Wenbo Li
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Xiang Xu
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Peiying Liu
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - John J Strouse
- Department of Pediatrics, Division of Pediatric Hematology, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Division of Hematology, Duke University, Durham, North Carolina
| | - James F Casella
- Department of Pediatrics, Division of Pediatric Hematology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Hanzhang Lu
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Peter C M van Zijl
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Qin Qin
- Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
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15
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Karthikeyan S, Fiksenbaum L, Grigorian A, Lu H, MacIntosh BJ, Goldstein BI. Normal Cerebral Oxygen Consumption Despite Elevated Cerebral Blood Flow in Adolescents With Bipolar Disorder: Putative Neuroimaging Evidence of Anomalous Energy Metabolism. Front Psychiatry 2019; 10:739. [PMID: 31681045 PMCID: PMC6798187 DOI: 10.3389/fpsyt.2019.00739] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 09/16/2019] [Indexed: 12/22/2022] Open
Abstract
Background: Regional cerebral blood flow (CBF) is reportedly altered in both adolescents and adults with bipolar disorder (BD). Whether these CBF differences are part of an overall imbalance in cerebral energy homeostasis remains unknown. Therefore, we examined global cerebral metabolic rate of oxygen consumption (CMRO2) as a physiological index of brain metabolism in adolescents with and without BD. Methods: One hundred and fifteen adolescents (mean age 17.3 ± 1.4 years), including 58 BD (type I, II, or not otherwise specified [NOS]) and 57 age-matched healthy controls (HCs) participated in this magnetic resonance imaging (MRI) study. Global estimates for venous blood oxygenation (Yv) and grey matter CBF were measured using T2-relaxation-under-spin-tagging (TRUST) and arterial spin labeling (ASL) MRI, respectively. CMRO2 was calculated using the Fick principle of arteriovenous difference to test for a group difference. We also examined CMRO2 in relation to mood states (i.e. euthymic, depressed, or hypomanic/mixed). Results: Although CBF was significantly higher in BD compared to HCs, there was no group difference in global CMRO2, nor Yv. Meanwhile, Yv significantly decreased with age, and females tended to have greater CBF and CMRO2 in comparison to males. Lastly, there was no significant association between CMRO2 and mood states. Conclusions: Our results indicate a potential mismatch between cerebral blood supply and oxygen metabolism in BD, suggesting inefficiency in energy homeostasis in the brain. Mapping CMRO2 would provide the spatial resolution to investigate regional alterations in metabolism, particularly in the brain regions where CBF is increased.
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Affiliation(s)
- Sudhir Karthikeyan
- Centre for Youth Bipolar Disorder, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Lisa Fiksenbaum
- Centre for Youth Bipolar Disorder, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Anahit Grigorian
- Centre for Youth Bipolar Disorder, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Bradley J MacIntosh
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada.,Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada.,Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Benjamin I Goldstein
- Centre for Youth Bipolar Disorder, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.,Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.,Department of Pharmacology, University of Toronto, Toronto, ON, Canada.,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
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16
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Qi Y, Liu P, Lin Z, Lu H, Wang X. Hemodynamic and Metabolic Assessment of Neonates With Punctate White Matter Lesions Using Phase-Contrast MRI and T2-Relaxation-Under-Spin-Tagging (TRUST) MRI. Front Physiol 2018; 9:233. [PMID: 29615927 PMCID: PMC5868490 DOI: 10.3389/fphys.2018.00233] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 03/01/2018] [Indexed: 11/23/2022] Open
Abstract
The brain's hemodynamic and metabolism of punctate white matter lesions (PWML) is poorly understood due to a scarcity of non-invasive imaging techniques. The aim of this study was to apply new MRI techniques to quantify cerebral metabolic rate of oxygen (CMRO2), global cerebral blood flow (CBF), oxygen saturation fractions in venous blood (Yv) and oxygen extraction fraction (OEF) in neonates with PWML, for better understanding of the pathophysiology of PWML. Fifty-one newborns were recruited continuously, including 23 neonatal patients with PWML and 28 normal control neonates. Phase-contrast (PC) MRI and T2-Relaxation-Under-Spin-Tagging (TRUST) MRI were performed for the measurement of CBF and Yv. OEF and CMRO2 were calculated from the CBF and Yv values. The total maturation score (TMS) was assessed for each neonate on standard T1, 2-weighted images to evaluate cerebral maturation. The CMRO2, CBF, Yv, and OEF values were compared between groups, and their associations with age and TMS were evaluated. Significant differences between PWML group and control group were found in CMRO2 (P = 0.020), CBF (P = 0.027), Yv (P = 0.012), OEF (P = 0.018). After age/maturation is accounted for, Yv and OEF showed significant dependence on the groups (P < 0.05). Newborns with PWML had lower OEF and higher Yv. CMRO2, CBF and brain volume were correlated with age (P < 0.001) and TMS (P < 0.05). It is feasible to use non-invasive MRI methods to measure cerebral oxygen supply and consumption in neonates with PWML. Newborns with PWML have lower oxygen consumption. Yv and OEF may be helpful for the diagnosis of PWML. The positive correlation between CBF and TMS, and between CMRO2 and TMS suggested that as myelination progresses, the blood supply and oxygen metabolism in the brain increase to meet the escalating energy demand.
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Affiliation(s)
- Ying Qi
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Peiying Liu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Zixuan Lin
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Xiaoming Wang
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China
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17
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Uhlirova H, Kılıç K, Tian P, Sakadžić S, Gagnon L, Thunemann M, Desjardins M, Saisan PA, Nizar K, Yaseen MA, Hagler DJ, Vandenberghe M, Djurovic S, Andreassen OA, Silva GA, Masliah E, Kleinfeld D, Vinogradov S, Buxton RB, Einevoll GT, Boas DA, Dale AM, Devor A. The roadmap for estimation of cell-type-specific neuronal activity from non-invasive measurements. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0356. [PMID: 27574309 DOI: 10.1098/rstb.2015.0356] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/14/2016] [Indexed: 12/22/2022] Open
Abstract
The computational properties of the human brain arise from an intricate interplay between billions of neurons connected in complex networks. However, our ability to study these networks in healthy human brain is limited by the necessity to use non-invasive technologies. This is in contrast to animal models where a rich, detailed view of cellular-level brain function with cell-type-specific molecular identity has become available due to recent advances in microscopic optical imaging and genetics. Thus, a central challenge facing neuroscience today is leveraging these mechanistic insights from animal studies to accurately draw physiological inferences from non-invasive signals in humans. On the essential path towards this goal is the development of a detailed 'bottom-up' forward model bridging neuronal activity at the level of cell-type-specific populations to non-invasive imaging signals. The general idea is that specific neuronal cell types have identifiable signatures in the way they drive changes in cerebral blood flow, cerebral metabolic rate of O2 (measurable with quantitative functional Magnetic Resonance Imaging), and electrical currents/potentials (measurable with magneto/electroencephalography). This forward model would then provide the 'ground truth' for the development of new tools for tackling the inverse problem-estimation of neuronal activity from multimodal non-invasive imaging data.This article is part of the themed issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'.
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Affiliation(s)
- Hana Uhlirova
- Department of Radiology, UCSD, La Jolla, CA 92093, USA CEITEC-Central European Institute of Technology and Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Brno, Czech Republic
| | - Kıvılcım Kılıç
- Department of Neurosciences, UCSD, La Jolla, CA 92093, USA
| | - Peifang Tian
- Department of Neurosciences, UCSD, La Jolla, CA 92093, USA Department of Physics, John Carroll University, University Heights, OH 44118, USA
| | - Sava Sakadžić
- Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA 02129, USA
| | - Louis Gagnon
- Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA 02129, USA
| | | | | | - Payam A Saisan
- Department of Neurosciences, UCSD, La Jolla, CA 92093, USA
| | - Krystal Nizar
- Neurosciences Graduate Program, UCSD, La Jolla, CA 92093, USA
| | - Mohammad A Yaseen
- Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA 02129, USA
| | | | - Matthieu Vandenberghe
- Department of Radiology, UCSD, La Jolla, CA 92093, USA NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital and University of Oslo, 0407 Oslo, Norway
| | - Srdjan Djurovic
- Department of Medical Genetics, Oslo University Hospital, 0407 Oslo, Norway NORMENT, KG Jebsen Centre for Psychosis Research, Department of Clinical Science, University of Bergen, 5020 Bergen, Norway
| | - Ole A Andreassen
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital and University of Oslo, 0407 Oslo, Norway
| | - Gabriel A Silva
- Department of Bioengineering, UCSD, La Jolla, CA 92093, USA Department of Opthalmology, UCSD, La Jolla, CA 92093, USA
| | | | - David Kleinfeld
- Department of Physics, UCSD, La Jolla, CA 92093, USA Department of Electrical and Computer Engineering, UCSD, La Jolla, CA 92093, USA Section of Neurobiology, UCSD, La Jolla, CA 92093, USA
| | - Sergei Vinogradov
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | | - Gaute T Einevoll
- Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, 1432 Ås, Norway Department of Physics, University of Oslo, 0316 Oslo, Norway
| | - David A Boas
- Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA 02129, USA
| | - Anders M Dale
- Department of Radiology, UCSD, La Jolla, CA 92093, USA Department of Neurosciences, UCSD, La Jolla, CA 92093, USA
| | - Anna Devor
- Department of Radiology, UCSD, La Jolla, CA 92093, USA Department of Neurosciences, UCSD, La Jolla, CA 92093, USA Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, MA 02129, USA
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18
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Xu F, Li W, Liu P, Hua J, Strouse JJ, Pekar JJ, Lu H, van Zijl PCM, Qin Q. Accounting for the role of hematocrit in between-subject variations of MRI-derived baseline cerebral hemodynamic parameters and functional BOLD responses. Hum Brain Mapp 2017; 39:344-353. [PMID: 29024300 DOI: 10.1002/hbm.23846] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 09/22/2017] [Accepted: 10/04/2017] [Indexed: 12/19/2022] Open
Abstract
Baseline hematocrit fraction (Hct) is a determinant for baseline cerebral blood flow (CBF) and between-subject variation of Hct thus causes variation in task-based BOLD fMRI signal changes. We first verified in healthy volunteers (n = 12) that Hct values can be derived reliably from venous blood T1 values by comparison with the conventional lab test. Together with CBF measured using phase-contrast MRI, this noninvasive estimation of Hct, instead of using a population-averaged Hct value, enabled more individual determination of oxygen delivery (DO2 ), oxygen extraction fraction (OEF), and cerebral metabolic rate of oxygen (CMRO2 ). The inverse correlation of CBF and Hct explained about 80% of between-subject variation of CBF in this relatively uniform cohort of subjects, as expected based on the regulation of DO2 to maintain constant CMRO2 . Furthermore, we compared the relationships of visual task-evoked BOLD response with Hct and CBF. We showed that Hct and CBF contributed 22%-33% of variance in BOLD signal and removing the positive correlation with Hct and negative correlation with CBF allowed normalization of BOLD signal with 16%-22% lower variability. The results of this study suggest that adjustment for Hct effects is useful for studies of MRI perfusion and BOLD fMRI. Hum Brain Mapp 39:344-353, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Feng Xu
- The Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland.,Developing Brain Research Lab, Children's National Medical Center, Washington DC, Washington
| | - Wenbo Li
- The Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Peiying Liu
- The Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Jun Hua
- The Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - John J Strouse
- Division of Hematology, Department of Medicine, Duke University, Durham, North Carolina
| | - James J Pekar
- The Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Peter C M van Zijl
- The Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Qin Qin
- The Russell H. Morgan Department of Radiology and Radiological Science, Division of MR Research, Johns Hopkins University School of Medicine, Baltimore, Maryland.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
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19
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Driver ID, Wise RG, Murphy K. Graded Hypercapnia-Calibrated BOLD: Beyond the Iso-metabolic Hypercapnic Assumption. Front Neurosci 2017; 11:276. [PMID: 28572755 PMCID: PMC5435758 DOI: 10.3389/fnins.2017.00276] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 04/28/2017] [Indexed: 01/27/2023] Open
Abstract
Calibrated BOLD is a promising technique that overcomes the sensitivity of conventional fMRI to the cerebrovascular state; measuring either the basal level, or the task-induced response of cerebral metabolic rate of oxygen consumption (CMRO2). The calibrated BOLD method is susceptible to errors in the measurement of the calibration parameter M, the theoretical BOLD signal change that would occur if all deoxygenated hemoglobin were removed. The original and most popular method for measuring M uses hypercapnia (an increase in arterial CO2), making the assumption that it does not affect CMRO2. This assumption has since been challenged and recent studies have used a corrective term, based on literature values of a reduction in basal CMRO2 with hypercapnia. This is not ideal, as this value may vary across subjects and regions of the brain, and will depend on the level of hypercapnia achieved. Here we propose a new approach, using a graded hypercapnia design and the assumption that CMRO2 changes linearly with hypercapnia level, such that we can measure M without assuming prior knowledge of the scale of CMRO2 change. Through use of a graded hypercapnia gas challenge, we are able to remove the bias caused by a reduction in basal CMRO2 during hypercapnia, whilst simultaneously calculating the dose-wise CMRO2 change with hypercapnia. When compared with assuming no change in CMRO2, this approach resulted in significantly lower M-values in both visual and motor cortices, arising from significant dose-dependent hypercapnia reductions in basal CMRO2 of 1.5 ± 0.6%/mmHg (visual) and 1.8 ± 0.7%/mmHg (motor), where mmHg is the unit change in end-tidal CO2 level. Variability in the basal CMRO2 response to hypercapnia, due to experimental differences and inter-subject variability, is accounted for in this approach, unlike previous correction approaches, which use literature values. By incorporating measurement of, and correction for, the reduction in basal CMRO2 during hypercapnia in the measurement of M-values, application of our approach will correct for an overestimation in both CMRO2 task-response values and absolute CMRO2.
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Affiliation(s)
- Ian D Driver
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff UniversityCardiff, United Kingdom
| | - Richard G Wise
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff UniversityCardiff, United Kingdom
| | - Kevin Murphy
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff UniversityCardiff, United Kingdom.,School of Physics and Astronomy, Cardiff UniversityCardiff, United Kingdom
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20
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Cao W, Chang YV, Englund EK, Song HK, Barhoum S, Rodgers ZB, Langham MC, Wehrli FW. High-speed whole-brain oximetry by golden-angle radial MRI. Magn Reson Med 2017; 79:217-223. [PMID: 28342212 DOI: 10.1002/mrm.26666] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Revised: 01/18/2017] [Accepted: 02/11/2017] [Indexed: 11/08/2022]
Abstract
PURPOSE To determine whole-brain cerebral metabolic rate of oxygen (CMRO2 ), an improved imaging approach, based on radial encoding, termed radial OxFlow (rOxFlow), was developed to simultaneously quantify draining vein venous oxygen saturation (SvO2 ) and total cerebral blood flow (tCBF). METHODS To evaluate the efficiency and precision of the rOxFlow sequence, 10 subjects were studied during a paradigm of repeated breath-holds with both rOxFlow and Cartesian OxFlow (cOxFlow) sequences. CMRO2 was calculated at baseline from OxFlow-measured data assuming an arterial O2 saturation of 97%, and the SvO2 and tCBF breath-hold responses were quantified. RESULTS Average neurometabolic-vascular parameters across the 10 subjects for cOxFlow and rOxFlow were, respectively: SvO2 (%) baseline: 64.6 ± 8.0 versus 64.2 ± 6.6; SvO2 peak: 70.5 ± 8.5 versus 72.6 ± 5.4; tCBF (mL/min/100 g) baseline: 39.2 ± 3.8 versus 40.6 ± 8.0; tCBF peak: 53.2 ± 5.1 versus 56.1 ± 11.7; CMRO2 (µmol O2 /min/100 g) baseline: 111.5 ± 26.8 versus 120.1 ± 19.6. The above measures were not significantly different between sequences (P > 0.05). CONCLUSION There was good agreement between the two methods in terms of the physiological responses measured. Comparing the two, rOxFlow provided higher temporal resolution and greater flexibility for reconstruction while maintaining high SNR. Magn Reson Med 79:217-223, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Wen Cao
- Laboratory for Structural, Physiologic and Functional Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Yulin V Chang
- Laboratory for Structural, Physiologic and Functional Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Erin K Englund
- Laboratory for Structural, Physiologic and Functional Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Hee Kwon Song
- Laboratory for Structural, Physiologic and Functional Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Suliman Barhoum
- Laboratory for Structural, Physiologic and Functional Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Zachary B Rodgers
- Laboratory for Structural, Physiologic and Functional Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Michael C Langham
- Laboratory for Structural, Physiologic and Functional Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Felix W Wehrli
- Laboratory for Structural, Physiologic and Functional Imaging, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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21
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Rodrigues Barreto F, Mangia S, Garrido Salmon CE. Effects of reduced oxygen availability on the vascular response and oxygen consumption of the activated human visual cortex. J Magn Reson Imaging 2016; 46:142-149. [PMID: 27807911 DOI: 10.1002/jmri.25537] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 10/18/2016] [Indexed: 11/11/2022] Open
Abstract
PURPOSE To identify the impact of reduced oxygen availability on the evoked vascular response upon visual stimulation in the healthy human brain by magnetic resonance imaging (MRI). MATERIALS AND METHODS Functional MRI techniques based on arterial spin labeling (ASL), blood oxygenation level-dependent (BOLD), and vascular space occupancy (VASO)-dependent contrasts were utilized to quantify the BOLD signal, cerebral blood flow (CBF), and volume (CBV) from nine subjects at 3T (7M/2F, 27.3 ± 3.6 years old) during normoxia and mild hypoxia. Changes in visual stimulus-induced oxygen consumption rates were also estimated with mathematical modeling. RESULTS Significant reductions in the extension of activated areas during mild hypoxia were observed in all three imaging contrasts: by 42.7 ± 25.2% for BOLD (n = 9, P = 0.002), 33.1 ± 24.0% for ASL (n = 9, P = 0.01), and 31.9 ± 15.6% for VASO images (n = 7, P = 0.02). Activated areas during mild hypoxia showed responses with similar amplitude for CBF (58.4 ± 18.7% hypoxia vs. 61.7 ± 16.1% normoxia, P = 0.61) and CBV (33.5 ± 17.5% vs. 25.2 ± 13.0%, P = 0.27), but not for BOLD (2.5 ± 0.8% vs. 4.1 ± 0.6%, P = 0.009). The estimated stimulus-induced increases of oxygen consumption were smaller during mild hypoxia as compared to normoxia (3.1 ± 5.0% vs. 15.5 ± 15.1%, P = 0.04). CONCLUSION Our results demonstrate an altered vascular and metabolic response during mild hypoxia upon visual stimulation. LEVEL OF EVIDENCE 2 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:142-149.
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Affiliation(s)
| | - Silvia Mangia
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA
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22
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Abstract
Oxygen plays a fundamental role in functional magnetic resonance imaging (FMRI). Blood oxygenation level-dependent (BOLD) imaging is the foundation stone of all FMRI and is still the essential workhorse of the vast majority of FMRI procedures. Hemoglobin may provide the magnetic properties that allow the technique to work, but it is oxygen that allows the contrast to effectively be switched on or off, and it is oxygen that we are interested in tracking in order to observe the oxygen metabolism changes. In general the changes in venous oxygen saturation are observed in order to infer changes in the correlated mechanisms, which can include changes in cerebral blood flow, metabolism, and the fraction of inspired oxygen. By independently manipulating the fraction of inspired oxygen it is possible to alter the amount of dissolved oxygen in the plasma, the venous saturation, or even the blood flow. The effects that these changes have on the observed MRI signal can be either a help or a hindrance depending on how well the changes induced are understood. The administration of supplemental inspired oxygen is in a unique position to provide a flexible, noninvasive, inexpensive, patient-friendly addition to the MRI toolkit to enable investigations to look beyond statistics and regions of interest, and actually produce calibrated, targeted measurements of blood flow, metabolism or pathology.
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Affiliation(s)
- Daniel Bulte
- FMRIB Centre, John Radcliffe Hospital, University of Oxford, Oxford, UK.
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23
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Maeda Y, Kudomi N, Sasakawa Y, Monden T, Kato K, Yamamoto Y, Kawai N, Nishiyama Y. Applicability of emission-based attenuation map for rapid CBF, OEF, and CMRO2 measurements using gaseous (15)O-labeled compounds. EJNMMI Phys 2015; 2:12. [PMID: 26501813 PMCID: PMC4545766 DOI: 10.1186/s40658-015-0115-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 04/20/2015] [Indexed: 12/01/2022] Open
Abstract
Background Cerebral blood flow (CBF), oxygen extraction fraction (OEF), and cerebral metabolic rate of oxygen (CMRO2) images have facilitated understanding of the pathophysiological basis of cerebrovascular disorders. Such parametric images can be rapidly, measured within around 15 min, using positron emission tomography (PET) with sequentially administered 15O-labeled oxygen and water. For further shortening, one option is to eliminate the transmission scan by applying an emission-based attenuation correction. Methods The validity of the present method was tested by comparing parametric values with emission-based attenuation correction to those with transmission-based correction. This was applied to 27 subjects who were diagnosed with or without cerebrovascular disorders. All subjects received the rapid CBF/OEF/CMRO2 PET measurements. An emission-based attenuation map was generated by estimating the edge of the brain tissue contour on an obtained sinogram and by assuming the uniform tissue coefficient to be 0.1 cm−1. Then images were reconstructed, and parametric images were computed. Results No difference was apparent between the emission- and transmission-based methods. Paired t-test showed no significant differences in CBF, OEF, or CMRO2 values between the emission- and transmission-based methods, except in the parietal and occipital and cerebellum and occipital regions, and the differences were less than 10%. The regression analysis showed a close correlation of r = 0.89 to 0.99. Conclusions The present study revealed that the attenuation correction can be performed by the emission-based estimation method and clinical PET duration can be shortened for the CBF, OEF, and CMRO2 gas study.
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Affiliation(s)
- Yukito Maeda
- Division of Social and Environmental Medicine, Graduate School of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan. .,Department of Clinical Radiology, Kagawa University Hospital, Kagawa, 761-0793, Japan.
| | - Nobuyuki Kudomi
- Department of Medical Physics, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan.
| | - Yasuhiro Sasakawa
- Department of Clinical Radiology, Kagawa University Hospital, Kagawa, 761-0793, Japan.
| | - Toshihide Monden
- Department of Clinical Radiology, Kagawa University Hospital, Kagawa, 761-0793, Japan.
| | - Koji Kato
- Department of Clinical Radiology, Kagawa University Hospital, Kagawa, 761-0793, Japan.
| | - Yuka Yamamoto
- Department of Radiology, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan.
| | - Nobuyuki Kawai
- Department of Neurological Surgery, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan.
| | - Yoshihiro Nishiyama
- Department of Radiology, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan.
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24
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Krishnamurthy LC, Mao D, King KS, Lu H. Correction and optimization of a T2-based approach to map blood oxygenation in small cerebral veins. Magn Reson Med 2015; 75:1100-9. [PMID: 25846113 DOI: 10.1002/mrm.25686] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 01/28/2015] [Accepted: 02/17/2015] [Indexed: 12/11/2022]
Abstract
PURPOSE Cerebral venous blood oxygenation (Yv ) is an important biomarker in brain physiology and function. The present study proposes a procedure to provide a quantitative map of the brain's intravascular Yv. THEORY AND METHODS The method is based on a pulse sequence, T2 -Relaxation-Under-Phase-Contrast (TRU-PC) MRI, with postprocessing approaches to correct eddy-current effects. A complete scan protocol consists of four TRU-PC scans sensitized to large and small vessels with anterior-posterior and foot-head flow-encoding directions, and the data are analyzed conjunctively. Eddy-current correction was performed by fitting the tissue phase to a hyperplane, and then subtracting the eddy-current phase from the measured vessel phase. The reproducibility of the Yv-maps was examined in five participants. Sensitivity of the Yv map to a caffeine challenge was studied in another five participants. RESULTS Removal of eddy-current induced artifact allowed for the correction of T2 measurements, as demonstrated in vivo and with simulation. A Yv-map depicting all vessels in the slice can be obtained with the proposed protocol. Test-retest variability of the Yv -map was 3.7 ± 1.2%. Yv reduction can be reliably detected (P < 0.001) following the caffeine ingestion. CONCLUSION With the proposed TRU-PC protocol and eddy-current correction procedure, an accurate, vessel-specific Yv map of the human brain can be obtained.
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Affiliation(s)
- Lisa C Krishnamurthy
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Department of Biomedical Engineering, University of Texas at Arlington, Arlington, Texas, USA
| | - Deng Mao
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Kevin S King
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Hanzhang Lu
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Department of Radiology, Johns Hopkins University, Baltimore, Maryland, USA
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25
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Jessen SB, Brazhe A, Lind BL, Mathiesen C, Thomsen K, Jensen K, Lauritzen M. GABAA Receptor-Mediated Bidirectional Control of Synaptic Activity, Intracellular Ca2+, Cerebral Blood Flow, and Oxygen Consumption in Mouse Somatosensory Cortex In Vivo. Cereb Cortex 2014; 25:2594-609. [PMID: 24692513 DOI: 10.1093/cercor/bhu058] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Neural activity regulates local increases in cerebral blood flow (ΔCBF) and the cortical metabolic rate of oxygen (ΔCMRO2) that constitutes the basis of BOLD functional neuroimaging signals. Glutamate signaling plays a key role in brain vascular and metabolic control; however, the modulatory effect of GABA is incompletely understood. Here we performed in vivo studies in mice to investigate how THIP (which tonically activates extrasynaptic GABAARs) and Zolpidem (a positive allosteric modulator of synaptic GABAARs) impact stimulation-induced ΔCBF, ΔCMRO2, local field potentials (LFPs), and fluorescent cytosolic Ca(2+) transients in neurons and astrocytes. Low concentrations of THIP increased ΔCBF and ΔCMRO2 at low stimulation frequencies. These responses were coupled to increased synaptic activity as indicated by LFP responses, and to Ca(2+) activities in neurons and astrocytes. Intermediate and high concentrations of THIP suppressed ΔCBF and ΔCMRO2 at high stimulation frequencies. Zolpidem had similar but less-pronounced effects, with similar dependence on drug concentration and stimulation frequency. Our present findings suggest that slight increases in both synaptic and extrasynaptic GABAAR activity might selectively gate and amplify transient low-frequency somatosensory inputs, filter out high-frequency inputs, and enhance vascular and metabolic responses that are likely to be reflected in BOLD functional neuroimaging signals.
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Affiliation(s)
- Sanne Barsballe Jessen
- Department of Neuroscience and Pharmacology, University of Copenhagen, 2200 Copenhagen N, Denmark Center for Healthy Aging, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Alexey Brazhe
- Biological Faculty Moscow State University, 119234 Moscow, Russia
| | - Barbara Lykke Lind
- Department of Neuroscience and Pharmacology, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Claus Mathiesen
- Department of Neuroscience and Pharmacology, University of Copenhagen, 2200 Copenhagen N, Denmark Center for Healthy Aging, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Kirsten Thomsen
- Department of Neuroscience and Pharmacology, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Kimmo Jensen
- Synaptic Physiology Laboratory, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Martin Lauritzen
- Department of Neuroscience and Pharmacology, University of Copenhagen, 2200 Copenhagen N, Denmark Center for Healthy Aging, University of Copenhagen, 2200 Copenhagen N, Denmark Department of Clinical Neurophysiology, Glostrup Hospital, 2600 Glostrup, Denmark
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26
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Liu P, Huang H, Rollins N, Chalak LF, Jeon T, Halovanic C, Lu H. Quantitative assessment of global cerebral metabolic rate of oxygen ( CMRO2) in neonates using MRI. NMR Biomed 2014; 27:332-40. [PMID: 24399806 PMCID: PMC3970939 DOI: 10.1002/nbm.3067] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 11/27/2013] [Accepted: 11/29/2013] [Indexed: 05/30/2023]
Abstract
The cerebral metabolic rate of oxygen (CMRO2) is the rate of oxygen consumption by the brain, and is thought to be a direct index of energy homeostasis and brain health. However, in vivo measurement of CMRO2 is challenging, in particular for the neonatal population, in whom conventional radiotracer methods are not applicable because of safety concerns. In this study, we propose a method to quantify global CMRO2 in neonates based on arteriovenous differences in oxygen content, and employ separate measurements of oxygenation and cerebral blood flow (CBF) parameters. Specifically, arterial and venous oxygenation levels were determined with pulse oximetry and the novel T2 relaxation under spin tagging (TRUST) MRI, respectively. Global CBF was measured with phase contrast (PC) flow velocity MRI. The proposed method was implemented on a standard 3-T MRI scanner without the need for any exogenous tracers, and the total scan duration was less than 5 min. We demonstrated the feasibility of this method in 12 healthy neonates within an age range of 35-42 gestational weeks. CMRO2 values were successfully obtained from 10 neonates. It was found that the average CMRO2 in this age range was 38.3 ± 17.7 µmol/100 g/min and was positively correlated with age (p = 0.007; slope, 5.2 µmol/100 g/min per week), although the highest CMRO2 value in this age range was still less than half of the adult level. Test-retest studies showed a coefficient of variation of 5.8 ± 2.2% between repeated CMRO2 measurements. In addition, given the highly variable blood flow velocity within this age range, it is recommended that the TRUST labeling thickness and position should be determined on a subject-by-subject basis, and an automatic algorithm was developed for this purpose. Although this method provides a global CMRO2 measure only, the clinical significance of an energy consumption marker and the convenience of this technique may make it a useful tool in the functional assessment of the neonatal population.
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Affiliation(s)
- Peiying Liu
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Texas, United States
| | - Hao Huang
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Texas, United States
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Nancy Rollins
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
- Children’s Medical Center of Dallas, Dallas, Texas, United States
| | - Lina F. Chalak
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Tina Jeon
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Texas, United States
| | - Cathy Halovanic
- Children’s Medical Center of Dallas, Dallas, Texas, United States
| | - Hanzhang Lu
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Texas, United States
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
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27
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Abstract
The precise mechanisms that give rise to the blood-oxygen-level-dependent (BOLD) activation differences that accompany age-related cognitive slowing remain fundamentally unknown. We sought to isolate the origin of age-related BOLD changes by comparing blood-flow and oxygen-metabolic constituents of the BOLD response using dual-echo arterial spin labeling during visual stimulation and CO2 ingestion. We hypothesized, and our results confirmed, that age-related changes in the ratio of fractional cerebral blood flow to fractional cerebral metabolic rate of oxygen consumption (ΔCBF/ΔCMRO2) lead to the BOLD changes that are observed in older adults. ΔCBF/ΔCMRO2 was also significantly related to performance, suggesting that age-related cognitive slowing results from neural cell assemblies that operate less efficiently, requiring greater oxygen metabolism that is not matched by blood-flow changes relative to younger adults. Age-related changes in ΔCBF/ΔCMRO2 are sufficient to explain variations in BOLD responding and performance cited throughout the literature, assuming no bias based on physiological baseline CMRO2.
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Affiliation(s)
- Joanna L Hutchison
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX 75080, USA
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28
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Hutchison JL, Shokri-Kojori E, Lu H, Rypma B. A BOLD Perspective on Age-Related Neurometabolic-Flow Coupling and Neural Efficiency Changes in Human Visual Cortex. Front Psychol 2013; 4:244. [PMID: 23653614 PMCID: PMC3642502 DOI: 10.3389/fpsyg.2013.00244] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2013] [Accepted: 04/14/2013] [Indexed: 11/22/2022] Open
Abstract
Age-related performance declines in visual tasks have been attributed to reductions in processing efficiency. The neural basis of these declines has been explored by comparing the blood-oxygen-level-dependent (BOLD) index of neural activity in older and younger adults during visual task performance. However, neural activity is one of many factors that change with age and lead to BOLD signal differences. We investigated the origin of age-related BOLD changes by comparing blood flow and oxygen metabolic constituents of BOLD signal. Subjects periodically viewed flickering annuli and pressed a button when detecting luminance changes in a central fixation cross. Using magnetic resonance dual-echo arterial spin labeling and CO2 ingestion, we observed age-equivalent (i.e., similar in older and younger groups) fractional cerebral blood flow (ΔCBF) in the presence of age-related increases in fractional cerebral metabolic rate of oxygen (ΔCMRO2). Reductions in ΔCBF responsiveness to increased ΔCMRO2 in elderly led to paradoxical age-related BOLD decreases. Age-related ΔCBF/ΔCMRO2 ratio decreases were associated with reaction times, suggesting that age-related slowing resulted from less efficient neural activity. We hypothesized that reduced vascular responsiveness to neural metabolic demand would lead to a reduction in ΔCBF/ΔCMRO2. A simulation of BOLD relative to ΔCMRO2 for lower and higher neurometabolic-flow coupling ratios (approximating those for old and young, respectively) indicated less BOLD signal change in old than young in relatively lower CMRO2 ranges, as well as greater BOLD signal change in young compared to old in relatively higher CMRO2 ranges. These results suggest that age-comparative studies relying on BOLD signal might be misinterpreted, as age-related BOLD changes do not merely reflect neural activity changes. Age-related declines in neurometabolic-flow coupling might lead to neural efficiency reductions that can adversely affect visual task performance.
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Affiliation(s)
- Joanna Lynn Hutchison
- School of Behavioral and Brain Sciences, University of Texas at DallasRichardson, TX, USA
- Department of Psychiatry, University of Texas Southwestern Medical CenterDallas, TX, USA
| | - Ehsan Shokri-Kojori
- School of Behavioral and Brain Sciences, University of Texas at DallasRichardson, TX, USA
| | - Hanzhang Lu
- Advanced Imaging Research Center, University of Texas Southwestern Medical CenterDallas, TX, USA
| | - Bart Rypma
- School of Behavioral and Brain Sciences, University of Texas at DallasRichardson, TX, USA
- Department of Psychiatry, University of Texas Southwestern Medical CenterDallas, TX, USA
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Lin AL, Lu H, Fox PT, Duong TQ. Cerebral Blood Volume Measurements - Gd_DTPA vs. VASO - and Their Relationship with Cerebral Blood Flow in Activated Human Visual Cortex. Open Neuroimag J 2011; 5:90-5. [PMID: 22253653 PMCID: PMC3245406 DOI: 10.2174/1874440001105010090] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2010] [Revised: 02/03/2011] [Accepted: 03/13/2011] [Indexed: 11/22/2022] Open
Abstract
Measurements of task-induced changes in cerebral blood volume (CBV) have been demonstrated using VAscular Space Occupancy (VASO) techniques (noninvasive and newly developed) and a contrast agent-based (Gd- DTPA) method (invasive but well-established) with functional magnetic resonance imaging (fMRI). We compared the two methods in determining CBV changes during multi-frequency visual stimulation (4 and 8 Hz). Specifically, we aimed to assess the impact of repetition time (TR) on CBV changes determination using VASO. With additional measurements of cerebral blood flow (CBF), the flow-volume coupling relationship (α value) and cerebral metabolic rate of oxygen were further determined. The results showed that i) using VASO, short TR (2s) caused overestimation of CBV changes, while long TR (6s) generated consistent CBV results, by comparison to the GD-DTPA method; ii) overestimation of CBV changes caused underestimated CMRO2 changes, but did not alter the frequency-related pattern, i.e., CMRO2 changes at 4 Hz were greater than those at 8 Hz regardless of the TR; and iii) the tasked-induced CBF-CBV coupling was stimulus frequency-dependent, i.e., α = 0.35-0.38 at 4 Hz and α = 0.51-0.53 at 8 Hz. Our data demonstrated that, with carefully chosen TRs, CBV measurements can be achieved non-invasively with VASO techniques.
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Affiliation(s)
- Ai-Ling Lin
- Research Imaging Institute, University of Texas Health Science Center, San Antonio, TX 78229, USA
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Abstract
Metabolic physiology and functional neuroimaging have played important and complementary roles over the past two decades. In particular, investigations of the mechanisms underlying functional neuroimaging signals have produced fundamental new insights into hemodynamic and metabolic regulation. However, controversies were also raised as regards the metabolic pathways (oxidative vs. non-oxidative) for meeting the energy demand and driving the increases in cerebral blood flow (CBF) during brain activation. In a recent study, with the concurrent functional MRI-MRS measurements, we found that task-evoked energy demand was predominately met through oxidative metabolism (approximately 98%), despite a small increase in cerebral metabolic rate of oxygen (12–17%). In addition, the task-induced increases in CBF were most likely mediated by anaerobic glycolysis rather than oxygen demand. These observations and others from functional neuroimaging support the activation-induced neuron-astrocyte interactions portrayed by the astrocyte-neuron lactate shuttle model. The concurrent developments of neuroimaging methods and metabolic physiology will also pave the way for the future investigation of cerebral hemodynamics and metabolism in disease states.
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Affiliation(s)
- Ai-Ling Lin
- Research Imaging Institute, University of Texas Health Science Center San Antonio, TX, USA
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Yücel MA, Devor A, Akin A, Boas DA. The Possible Role of CO(2) in Producing A Post-Stimulus CBF and BOLD Undershoot. Front Neuroenergetics 2009; 1:7. [PMID: 20027233 PMCID: PMC2795469 DOI: 10.3389/neuro.14.007.2009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Accepted: 10/08/2009] [Indexed: 12/04/2022]
Abstract
Comprehending the underlying mechanisms of neurovascular coupling is important for understanding the pathogenesis of neurodegenerative diseases related to uncoupling. Moreover, it elucidates the casual relation between the neural signaling and the hemodynamic responses measured with various imaging modalities such as functional magnetic resonance imaging (fMRI). There are mainly two hypotheses concerning this mechanism: a metabolic hypothesis and a neurogenic hypothesis. We have modified recent models of neurovascular coupling adding the effects of both NO (nitric oxide) kinetics, which is a well-known neurogenic vasodilator, and CO2 kinetics as a metabolic vasodilator. We have also added the Hodgkin–Huxley equations relating the membrane potentials to sodium influx through the membrane. Our results show that the dominant factor in the hemodynamic response is NO, however CO2 is important in producing a brief post-stimulus undershoot in the blood flow response that in turn modifies the fMRI blood oxygenation level-dependent post-stimulus undershoot. Our results suggest that increased cerebral blood flow during stimulation causes CO2 washout which then results in a post-stimulus hypocapnia induced vasoconstrictive effect.
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Affiliation(s)
- Meryem A Yücel
- Institute of Biomedical Engineering, Boğaziçi University Istanbul, Turkey
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