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Wang Q, Pan M, Kreiss L, Samaei S, Carp SA, Johansson JD, Zhang Y, Wu M, Horstmeyer R, Diop M, Li DDU. A comprehensive overview of diffuse correlation spectroscopy: theoretical framework, recent advances in hardware, analysis, and applications. Neuroimage 2024:120793. [PMID: 39153520 DOI: 10.1016/j.neuroimage.2024.120793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2024] [Revised: 07/23/2024] [Accepted: 08/14/2024] [Indexed: 08/19/2024] Open
Abstract
Diffuse correlation spectroscopy (DCS) is a powerful tool for assessing microvascular hemodynamic in deep tissues. Recent advances in sensors, lasers, and deep learning have further boosted the development of new DCS methods. However, newcomers might feel overwhelmed, not only by the already-complex DCS theoretical framework but also by the broad range of component options and system architectures. To facilitate new entry to this exciting field, we present a comprehensive review of DCS hardware architectures (continuous-wave, frequency-domain, and time-domain) and summarize corresponding theoretical models. Further, we discuss new applications of highly integrated silicon single-photon avalanche diode (SPAD) sensors in DCS, compare SPADs with existing sensors, and review other components (lasers, sensors, and correlators), as well as data analysis tools, including deep learning. Potential applications in medical diagnosis are discussed and an outlook for the future directions is provided, to offer effective guidance to embark on DCS research.
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Affiliation(s)
- Quan Wang
- University of Strathclyde, Department of Biomedical Engineering, Faculty of Engineering, Glasgow, United Kingdom
| | - Mingliang Pan
- University of Strathclyde, Department of Biomedical Engineering, Faculty of Engineering, Glasgow, United Kingdom
| | - Lucas Kreiss
- Duke University, Department of Biomedical Engineering, Durham, North Carolina, United States
| | - Saeed Samaei
- Western University, Department of Medical and Biophysics, Schulich School of Medical & Dentistry, London, Ontario, Canada; Imaging Program, Lawson Health Research Institute, London, Ontario, Canada
| | - Stefan A Carp
- Harvard Medical School, Massachusetts General Hospital, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, United States
| | | | - Yuanzhe Zhang
- University of Strathclyde, Department of Biomedical Engineering, Faculty of Engineering, Glasgow, United Kingdom
| | - Melissa Wu
- Duke University, Department of Biomedical Engineering, Durham, North Carolina, United States
| | - Roarke Horstmeyer
- Duke University, Department of Biomedical Engineering, Durham, North Carolina, United States
| | - Mamadou Diop
- Western University, Department of Medical and Biophysics, Schulich School of Medical & Dentistry, London, Ontario, Canada
| | - David Day-Uei Li
- University of Strathclyde, Department of Biomedical Engineering, Faculty of Engineering, Glasgow, United Kingdom.
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Robinson MB, Cheng TY, Renna M, Wu MM, Kim B, Cheng X, Boas DA, Franceschini MA, Carp SA. Comparing the performance potential of speckle contrast optical spectroscopy and diffuse correlation spectroscopy for cerebral blood flow monitoring using Monte Carlo simulations in realistic head geometries. NEUROPHOTONICS 2024; 11:015004. [PMID: 38282721 PMCID: PMC10821780 DOI: 10.1117/1.nph.11.1.015004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 12/13/2023] [Accepted: 01/08/2024] [Indexed: 01/30/2024]
Abstract
Significance The non-invasive measurement of cerebral blood flow based on diffuse optical techniques has seen increased interest as a research tool for cerebral perfusion monitoring in critical care and functional brain imaging. Diffuse correlation spectroscopy (DCS) and speckle contrast optical spectroscopy (SCOS) are two such techniques that measure complementary aspects of the fluctuating intensity signal, with DCS quantifying the temporal fluctuations of the signal and SCOS quantifying the spatial blurring of a speckle pattern. With the increasing interest in the use of these techniques, a thorough comparison would inform new adopters of the benefits of each technique. Aim We systematically evaluate the performance of DCS and SCOS for the measurement of cerebral blood flow. Approach Monte Carlo simulations of dynamic light scattering in an MRI-derived head model were performed. For both DCS and SCOS, estimates of sensitivity to cerebral blood flow changes, coefficient of variation of the measured blood flow, and the contrast-to-noise ratio of the measurement to the cerebral perfusion signal were calculated. By varying complementary aspects of data collection between the two methods, we investigated the performance benefits of different measurement strategies, including altering the number of modes per optical detector, the integration time/fitting time of the speckle measurement, and the laser source delivery strategy. Results Through comparison across these metrics with simulated detectors having realistic noise properties, we determine several guiding principles for the optimization of these techniques and report the performance comparison between the two over a range of measurement properties and tissue geometries. We find that SCOS outperforms DCS in terms of contrast-to-noise ratio for the cerebral blood flow signal in the ideal case simulated here but note that SCOS requires careful experimental calibrations to ensure accurate measurements of cerebral blood flow. Conclusion We provide design principles by which to evaluate the development of DCS and SCOS systems for their use in the measurement of cerebral blood flow.
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Affiliation(s)
- Mitchell B. Robinson
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Boston, Massachusetts, United States
| | - Tom Y. Cheng
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Boston, Massachusetts, United States
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Marco Renna
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Boston, Massachusetts, United States
| | - Melissa M. Wu
- Duke University, Department of Biomedical Engineering, Durham, North Carolina, United States
| | - Byungchan Kim
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Xiaojun Cheng
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - David A. Boas
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Maria Angela Franceschini
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Boston, Massachusetts, United States
| | - Stefan A. Carp
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Boston, Massachusetts, United States
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Cowdrick KR, Akbar M, Boodooram T, Harris LH, Bai S, Brothers RO, Arrington M, Lee SY, Khemani K, Gee B, Buckley EM. Impaired cerebrovascular reactivity in pediatric sickle cell disease using diffuse correlation spectroscopy. BIOMEDICAL OPTICS EXPRESS 2023; 14:5696-5708. [PMID: 38021121 PMCID: PMC10659811 DOI: 10.1364/boe.499274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/11/2023] [Accepted: 09/12/2023] [Indexed: 12/01/2023]
Abstract
Cerebrovascular reactivity (CVR), defined as the ability of cerebral vasculature to dilate in response to a vasodilatory stimulus, is an integral mechanism in brain homeostasis that is thought to be impaired in sickle cell disease (SCD). This study used diffuse correlation spectroscopy and a simple breath-hold stimulus to quantify CVR non-invasively in a cohort of 12 children with SCD and 14 controls. Median [interquartile range] CVR was significantly decreased in SCD compared to controls (2.03 [1.31, 2.44] versus 3.49 [3.00, 4.11] %/mmHg, p = 0.028). These results suggest DCS may provide a feasible means to routinely monitor CVR impairments in pediatric SCD.
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Affiliation(s)
- Kyle R. Cowdrick
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Drive NE, Atlanta, GA 30322, USA
| | - Mariam Akbar
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Drive NE, Atlanta, GA 30322, USA
| | - Tisha Boodooram
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Drive NE, Atlanta, GA 30322, USA
| | - LaBeausha H. Harris
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Drive NE, Atlanta, GA 30322, USA
| | - Shasha Bai
- Pediatric Biostatistics Core, Emory University School of Medicine, 1405 Clifton Road NE, Atlanta, GA 30322, USA
| | - Rowan O. Brothers
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Drive NE, Atlanta, GA 30322, USA
| | - Michael Arrington
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Drive NE, Atlanta, GA 30322, USA
| | - Seung Yup Lee
- Department of Electrical and Computer Engineering, Kennesaw State University, 840 Polytechnic Lane, Marietta, GA 30060, USA
| | - Kirsma Khemani
- Aflac Cancer and Blood Disorders Center, Division of Pediatric Hematology/Oncology, Children's Healthcare of Atlanta, 2015 Uppergate Drive, Atlanta, GA 30322, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Beatrice Gee
- Aflac Cancer and Blood Disorders Center, Division of Pediatric Hematology/Oncology, Children's Healthcare of Atlanta, 2015 Uppergate Drive, Atlanta, GA 30322, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Erin M. Buckley
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Drive NE, Atlanta, GA 30322, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
- Children's Research Scholar, Children's Healthcare of Atlanta, 2015 Uppergate Drive, Atlanta, GA 30322, USA
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Sanford EL, Akorede R, Miller I, Morriss MC, Nandy K, Raman L, Busch DR. Association Between Disrupted Cerebral Autoregulation and Radiographic Neurologic Injury for Children on Extracorporeal Membrane Oxygenation: A Prospective Pilot Study. ASAIO J 2023; 69:e315-e321. [PMID: 37172001 DOI: 10.1097/mat.0000000000001970] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023] Open
Abstract
Validation of a real-time monitoring device to evaluate the risk or occurrence of neurologic injury while on extracorporeal membrane oxygenation (ECMO) may aid clinicians in prevention and treatment. Therefore, we performed a pilot prospective cohort study of children under 18 years old on ECMO to analyze the association between cerebral blood pressure autoregulation as measured by diffuse correlation spectroscopy (DCS) and radiographic neurologic injury. DCS measurements of regional cerebral blood flow were collected on enrolled patients and correlated with mean arterial blood pressure to determine the cerebral autoregulation metric termed DCSx. The primary outcome of interest was radiographic neurologic injury on eligible computed tomography (CT) or magnetic resonance imaging (MRI) scored by a blinded pediatric neuroradiologist utilizing a previously validated scale. Higher DCSx scores, which indicate disruption of cerebral autoregulation, were associated with higher radiographic neurologic injury score (slope, 11.0; 95% confidence interval [CI], 0.29-22). Patients with clinically significant neurologic injury scores of 10 or more had higher median DCSx measures than patients with lower neurologic injury scores (0.48 vs . 0.13; p = 0.01). Our study indicates that obtaining noninvasive DCS measures for children on ECMO is feasible and disruption of cerebral autoregulation determined from DCS is associated with higher radiographic neurologic injury score.
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Affiliation(s)
- Ethan L Sanford
- From the Department of Anesthesiology and Pain Management, UT Southwestern Medical Center/Children's Medical Center, Dallas, Texas
- Division of Pediatric Critical Care Medicine, UT Southwestern Medical Center/Children's Medical Center, Dallas, Texas
| | - Rufai Akorede
- From the Department of Anesthesiology and Pain Management, UT Southwestern Medical Center/Children's Medical Center, Dallas, Texas
| | - Isabel Miller
- UT Southwestern Medical Center Medical School, Dallas, Texas
| | - Michael Craig Morriss
- Department of Radiology, UT Southwestern Medical Center/Children's Medical Center, Dallas, Texas
| | - Karabi Nandy
- Peter O'Donnell Jr. School of Public Health, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Lakshmi Raman
- Division of Pediatric Critical Care Medicine, UT Southwestern Medical Center/Children's Medical Center, Dallas, Texas
| | - David R Busch
- From the Department of Anesthesiology and Pain Management, UT Southwestern Medical Center/Children's Medical Center, Dallas, Texas
- Department of Neurology, UT Southwestern Medical Center, Dallas, Texas
- Department of Biomedical Engineering, UT Southwestern Medical Center, Dallas, Texas
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Cowdrick KR, Urner T, Sathialingam E, Fang Z, Quadri A, Turrentine K, Yup Lee S, Buckley EM. Agreement in cerebrovascular reactivity assessed with diffuse correlation spectroscopy across experimental paradigms improves with short separation regression. NEUROPHOTONICS 2023; 10:025002. [PMID: 37034012 PMCID: PMC10079775 DOI: 10.1117/1.nph.10.2.025002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 03/07/2023] [Indexed: 06/19/2023]
Abstract
Significance Cerebrovascular reactivity (CVR), i.e., the ability of cerebral vasculature to dilate or constrict in response to vasoactive stimuli, is a biomarker of vascular health. Exogenous administration of inhaled carbon dioxide, i.e., hypercapnia (HC), remains the "gold-standard" intervention to assess CVR. More tolerable paradigms that enable CVR quantification when HC is difficult/contraindicated have been proposed. However, because these paradigms feature mechanistic differences in action, an assessment of agreement of these more tolerable paradigms to HC is needed. Aim We aim to determine the agreement of CVR assessed during HC, breath-hold (BH), and resting state (RS) paradigms. Approach Healthy adults were subject to HC, BH, and RS paradigms. End tidal carbon dioxide (EtCO2) and cerebral blood flow (CBF, assessed with diffuse correlation spectroscopy) were monitored continuously. CVR (%/mmHg) was quantified via linear regression of CBF versus EtCO2 or via a general linear model (GLM) that was used to minimize the influence of systemic and extracerebral signal contributions. Results Strong agreement ( CCC ≥ 0.69 ; R ≥ 0.76 ) among CVR paradigms was demonstrated when utilizing a GLM to regress out systemic/extracerebral signal contributions. Linear regression alone showed poor agreement across paradigms ( CCC ≤ 0.35 ; R ≤ 0.45 ). Conclusions More tolerable experimental paradigms coupled with regression of systemic/extracerebral signal contributions may offer a viable alternative to HC for assessing CVR.
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Affiliation(s)
- Kyle R. Cowdrick
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Tara Urner
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Eashani Sathialingam
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Zhou Fang
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Ayesha Quadri
- Children’s Healthcare of Atlanta and Emory University School of Medicine, Department of Pediatrics, Atlanta, Georgia, United States
- Morehouse School of Medicine, Atlanta, Georgia, United States
| | - Katherine Turrentine
- Children’s Healthcare of Atlanta and Emory University School of Medicine, Department of Pediatrics, Atlanta, Georgia, United States
| | - Seung Yup Lee
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
- Kennesaw State University, Department of Electrical and Computer Engineering, Marietta, Georgia, United States
| | - Erin M. Buckley
- Georgia Institute of Technology and Emory University, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
- Children’s Healthcare of Atlanta and Emory University School of Medicine, Department of Pediatrics, Atlanta, Georgia, United States
- Children’s Healthcare of Atlanta, Children’s Research Scholar, Atlanta, Georgia, United States
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Ayaz H, Baker WB, Blaney G, Boas DA, Bortfeld H, Brady K, Brake J, Brigadoi S, Buckley EM, Carp SA, Cooper RJ, Cowdrick KR, Culver JP, Dan I, Dehghani H, Devor A, Durduran T, Eggebrecht AT, Emberson LL, Fang Q, Fantini S, Franceschini MA, Fischer JB, Gervain J, Hirsch J, Hong KS, Horstmeyer R, Kainerstorfer JM, Ko TS, Licht DJ, Liebert A, Luke R, Lynch JM, Mesquida J, Mesquita RC, Naseer N, Novi SL, Orihuela-Espina F, O’Sullivan TD, Peterka DS, Pifferi A, Pollonini L, Sassaroli A, Sato JR, Scholkmann F, Spinelli L, Srinivasan VJ, St. Lawrence K, Tachtsidis I, Tong Y, Torricelli A, Urner T, Wabnitz H, Wolf M, Wolf U, Xu S, Yang C, Yodh AG, Yücel MA, Zhou W. Optical imaging and spectroscopy for the study of the human brain: status report. NEUROPHOTONICS 2022; 9:S24001. [PMID: 36052058 PMCID: PMC9424749 DOI: 10.1117/1.nph.9.s2.s24001] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
This report is the second part of a comprehensive two-part series aimed at reviewing an extensive and diverse toolkit of novel methods to explore brain health and function. While the first report focused on neurophotonic tools mostly applicable to animal studies, here, we highlight optical spectroscopy and imaging methods relevant to noninvasive human brain studies. We outline current state-of-the-art technologies and software advances, explore the most recent impact of these technologies on neuroscience and clinical applications, identify the areas where innovation is needed, and provide an outlook for the future directions.
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Affiliation(s)
- Hasan Ayaz
- Drexel University, School of Biomedical Engineering, Science, and Health Systems, Philadelphia, Pennsylvania, United States
- Drexel University, College of Arts and Sciences, Department of Psychological and Brain Sciences, Philadelphia, Pennsylvania, United States
| | - Wesley B. Baker
- Children’s Hospital of Philadelphia, Division of Neurology, Philadelphia, Pennsylvania, United States
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Giles Blaney
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
| | - David A. Boas
- Boston University Neurophotonics Center, Boston, Massachusetts, United States
- Boston University, College of Engineering, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Heather Bortfeld
- University of California, Merced, Departments of Psychological Sciences and Cognitive and Information Sciences, Merced, California, United States
| | - Kenneth Brady
- Lurie Children’s Hospital, Northwestern University Feinberg School of Medicine, Department of Anesthesiology, Chicago, Illinois, United States
| | - Joshua Brake
- Harvey Mudd College, Department of Engineering, Claremont, California, United States
| | - Sabrina Brigadoi
- University of Padua, Department of Developmental and Social Psychology, Padua, Italy
| | - Erin M. Buckley
- Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
- Emory University School of Medicine, Department of Pediatrics, Atlanta, Georgia, United States
| | - Stefan A. Carp
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, United States
| | - Robert J. Cooper
- University College London, Department of Medical Physics and Bioengineering, DOT-HUB, London, United Kingdom
| | - Kyle R. Cowdrick
- Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Joseph P. Culver
- Washington University School of Medicine, Department of Radiology, St. Louis, Missouri, United States
| | - Ippeita Dan
- Chuo University, Faculty of Science and Engineering, Tokyo, Japan
| | - Hamid Dehghani
- University of Birmingham, School of Computer Science, Birmingham, United Kingdom
| | - Anna Devor
- Boston University, College of Engineering, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Turgut Durduran
- ICFO – The Institute of Photonic Sciences, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
- Institució Catalana de Recerca I Estudis Avançats (ICREA), Barcelona, Spain
| | - Adam T. Eggebrecht
- Washington University in St. Louis, Mallinckrodt Institute of Radiology, St. Louis, Missouri, United States
| | - Lauren L. Emberson
- University of British Columbia, Department of Psychology, Vancouver, British Columbia, Canada
| | - Qianqian Fang
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Sergio Fantini
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
| | - Maria Angela Franceschini
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, United States
| | - Jonas B. Fischer
- ICFO – The Institute of Photonic Sciences, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
| | - Judit Gervain
- University of Padua, Department of Developmental and Social Psychology, Padua, Italy
- Université Paris Cité, CNRS, Integrative Neuroscience and Cognition Center, Paris, France
| | - Joy Hirsch
- Yale School of Medicine, Department of Psychiatry, Neuroscience, and Comparative Medicine, New Haven, Connecticut, United States
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Keum-Shik Hong
- Pusan National University, School of Mechanical Engineering, Busan, Republic of Korea
- Qingdao University, School of Automation, Institute for Future, Qingdao, China
| | - Roarke Horstmeyer
- Duke University, Department of Biomedical Engineering, Durham, North Carolina, United States
- Duke University, Department of Electrical and Computer Engineering, Durham, North Carolina, United States
- Duke University, Department of Physics, Durham, North Carolina, United States
| | - Jana M. Kainerstorfer
- Carnegie Mellon University, Department of Biomedical Engineering, Pittsburgh, Pennsylvania, United States
- Carnegie Mellon University, Neuroscience Institute, Pittsburgh, Pennsylvania, United States
| | - Tiffany S. Ko
- Children’s Hospital of Philadelphia, Division of Cardiothoracic Anesthesiology, Philadelphia, Pennsylvania, United States
| | - Daniel J. Licht
- Children’s Hospital of Philadelphia, Division of Neurology, Philadelphia, Pennsylvania, United States
| | - Adam Liebert
- Polish Academy of Sciences, Nalecz Institute of Biocybernetics and Biomedical Engineering, Warsaw, Poland
| | - Robert Luke
- Macquarie University, Department of Linguistics, Sydney, New South Wales, Australia
- Macquarie University Hearing, Australia Hearing Hub, Sydney, New South Wales, Australia
| | - Jennifer M. Lynch
- Children’s Hospital of Philadelphia, Division of Cardiothoracic Anesthesiology, Philadelphia, Pennsylvania, United States
| | - Jaume Mesquida
- Parc Taulí Hospital Universitari, Critical Care Department, Sabadell, Spain
| | - Rickson C. Mesquita
- University of Campinas, Institute of Physics, Campinas, São Paulo, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology, Campinas, São Paulo, Brazil
| | - Noman Naseer
- Air University, Department of Mechatronics and Biomedical Engineering, Islamabad, Pakistan
| | - Sergio L. Novi
- University of Campinas, Institute of Physics, Campinas, São Paulo, Brazil
- Western University, Department of Physiology and Pharmacology, London, Ontario, Canada
| | | | - Thomas D. O’Sullivan
- University of Notre Dame, Department of Electrical Engineering, Notre Dame, Indiana, United States
| | - Darcy S. Peterka
- Columbia University, Zuckerman Mind Brain Behaviour Institute, New York, United States
| | | | - Luca Pollonini
- University of Houston, Department of Engineering Technology, Houston, Texas, United States
| | - Angelo Sassaroli
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
| | - João Ricardo Sato
- Federal University of ABC, Center of Mathematics, Computing and Cognition, São Bernardo do Campo, São Paulo, Brazil
| | - Felix Scholkmann
- University of Bern, Institute of Complementary and Integrative Medicine, Bern, Switzerland
- University of Zurich, University Hospital Zurich, Department of Neonatology, Biomedical Optics Research Laboratory, Zürich, Switzerland
| | - Lorenzo Spinelli
- National Research Council (CNR), IFN – Institute for Photonics and Nanotechnologies, Milan, Italy
| | - Vivek J. Srinivasan
- University of California Davis, Department of Biomedical Engineering, Davis, California, United States
- NYU Langone Health, Department of Ophthalmology, New York, New York, United States
- NYU Langone Health, Department of Radiology, New York, New York, United States
| | - Keith St. Lawrence
- Lawson Health Research Institute, Imaging Program, London, Ontario, Canada
- Western University, Department of Medical Biophysics, London, Ontario, Canada
| | - Ilias Tachtsidis
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Yunjie Tong
- Purdue University, Weldon School of Biomedical Engineering, West Lafayette, Indiana, United States
| | - Alessandro Torricelli
- Politecnico di Milano, Dipartimento di Fisica, Milan, Italy
- National Research Council (CNR), IFN – Institute for Photonics and Nanotechnologies, Milan, Italy
| | - Tara Urner
- Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Heidrun Wabnitz
- Physikalisch-Technische Bundesanstalt (PTB), Berlin, Germany
| | - Martin Wolf
- University of Zurich, University Hospital Zurich, Department of Neonatology, Biomedical Optics Research Laboratory, Zürich, Switzerland
| | - Ursula Wolf
- University of Bern, Institute of Complementary and Integrative Medicine, Bern, Switzerland
| | - Shiqi Xu
- Duke University, Department of Biomedical Engineering, Durham, North Carolina, United States
| | - Changhuei Yang
- California Institute of Technology, Department of Electrical Engineering, Pasadena, California, United States
| | - Arjun G. Yodh
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
| | - Meryem A. Yücel
- Boston University Neurophotonics Center, Boston, Massachusetts, United States
- Boston University, College of Engineering, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Wenjun Zhou
- University of California Davis, Department of Biomedical Engineering, Davis, California, United States
- China Jiliang University, College of Optical and Electronic Technology, Hangzhou, Zhejiang, China
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7
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Sakuma T, Shinomiya S, Takahara Y, Mizuno S. Awake Hypercapnic Ventilatory Response in Obstructive Sleep Apnea Syndrome. SLEEP MEDICINE RESEARCH 2022. [DOI: 10.17241/smr.2021.01172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background and Objective Decreased ventilatory response to carbon dioxide or hypercapnic ventilatory response (HCVR) is a feature of pediatric obstructive sleep apnea (OSA) and is also known to diminish during sleep in obese adolescents (age, 12–16 years) with OSA. It reduces minute ventilation, air flow, and tidal volume during inspiration, as well as upper airway obstruction. The purpose of this study was to investigate awake HCVR in adult patients with OSA and to elucidate its association with sleep apnea.Methods HCVR was measured before performing polysomnography (PSG). PSG is performed as the evaluation method during sleep, and the severity of apnea is evaluated by apnea hypopnea index. Patient background, PSG data and HCVR were examined.Results Awake HCVR was greater in patients with severe OSA than in patients with mild and moderate OSA, and in severe OSA patients, the HCVR during awaking was higher in patients with larger changes in saturation of percutaneous oxygen during sleep. Awake HCVR did not differ by age, but it was greater in morbidly obese patients with OSA than in thin patients with OSA. The most frequent apnea pattern of OSA was obstructive, regardless of severity; although with an increasing severity of OSA, the central pattern decreased and the mixed pattern increased in frequency. The appearance of the mixed pattern increased in the augmented HCVR group.Conclusions This study suggested that awake HCVR could be used as an index of progression and a factor to determine the effects of treatment in patients with OSA.
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8
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Bullock T, Giesbrecht B, Beaudin AE, Goodyear BG, Poulin MJ. Effects of changes in end-tidal PO 2 and PCO 2 on neural responses during rest and sustained attention. Physiol Rep 2021; 9:e15106. [PMID: 34755481 PMCID: PMC8578925 DOI: 10.14814/phy2.15106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/08/2021] [Accepted: 10/10/2021] [Indexed: 01/23/2023] Open
Abstract
Impairments of cognitive function during alterations in arterial blood gases (e.g., high-altitude hypoxia) may result from the disruption of neurovascular coupling; however, the link between changes in arterial blood gases, cognition, and cerebral blood flow (CBF) is poorly understood. To interrogate this link, we developed a multimodal empirical strategy capable of monitoring neural correlates of cognition and CBF simultaneously. Human participants performed a sustained attention task during hypoxia, hypercapnia, hypocapnia, and normoxia while electroencephalographic (EEG) activity and CBF (middle and posterior cerebral arteries; transcranial Doppler ultrasound) were simultaneously measured. The protocol alternated between rest and engaging in a visual target detection task that required participants to monitor a sequence of brief-duration colored circles and detect infrequent, longer duration circles (targets). The target detection task was overlaid on a large, circular checkerboard that provided robust visual stimulation. Spectral decomposition and event-related potential (ERP) analyses were applied to the EEG data to investigate spontaneous and task-specific fluctuations in neural activity. There were three main sets of findings: (1) spontaneous alpha oscillatory activity was modulated as a function of arterial CO2 (hypocapnia and hypercapnia), (2) task-related neurovascular coupling was disrupted by all arterial blood gas manipulations, and (3) changes in task-related alpha and theta band activity and attenuation of the P3 ERP component amplitude were observed during hypocapnia. Since alpha and theta are linked with suppression of visual processing and executive control and P3 amplitude with task difficulty, these data suggest that transient arterial blood gas changes can modulate multiple stages of cognitive information processing.
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Affiliation(s)
- Tom Bullock
- Department of Psychological and Brain SciencesUniversity of CaliforniaSanta BarbaraCaliforniaUSA
- Institute for Collaborative BiotechnologiesUniversity of CaliforniaSanta BarbaraCaliforniaUSA
| | - Barry Giesbrecht
- Department of Psychological and Brain SciencesUniversity of CaliforniaSanta BarbaraCaliforniaUSA
- Institute for Collaborative BiotechnologiesUniversity of CaliforniaSanta BarbaraCaliforniaUSA
- Interdepartmental Graduate Program in Dynamical NeuroscienceUniversity of CaliforniaSanta BarbaraCaliforniaUSA
| | - Andrew E. Beaudin
- Department of Physiology & PharmacologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteCumming School of MedicineUniversity of CalgaryCalgaryAlbertaCanada
| | - Bradley G. Goodyear
- Hotchkiss Brain InstituteCumming School of MedicineUniversity of CalgaryCalgaryAlbertaCanada
- Department of Clinical NeurosciencesUniversity of CalgaryCalgaryAlbertaCanada
- Department of RadiologyUniversity of CalgaryCalgaryAlbertaCanada
| | - Marc J. Poulin
- Department of Physiology & PharmacologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteCumming School of MedicineUniversity of CalgaryCalgaryAlbertaCanada
- Department of Clinical NeurosciencesUniversity of CalgaryCalgaryAlbertaCanada
- O’Brien Institute for Public HealthUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryCalgaryAlbertaCanada
- Faculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
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9
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Wu MM, Chan ST, Mazumder D, Tamborini D, Stephens KA, Deng B, Farzam P, Chu JY, Franceschini MA, Qu JZ, Carp SA. Improved accuracy of cerebral blood flow quantification in the presence of systemic physiology cross-talk using multi-layer Monte Carlo modeling. NEUROPHOTONICS 2021; 8:015001. [PMID: 33437846 PMCID: PMC7779997 DOI: 10.1117/1.nph.8.1.015001] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 12/09/2020] [Indexed: 05/08/2023]
Abstract
Significance: Contamination of diffuse correlation spectroscopy (DCS) measurements of cerebral blood flow (CBF) due to systemic physiology remains a significant challenge in the clinical translation of DCS for neuromonitoring. Tunable, multi-layer Monte Carlo-based (MC) light transport models have the potential to remove extracerebral flow cross-talk in cerebral blood flow index ( CBF i ) estimates. Aim: We explore the effectiveness of MC DCS models in recovering accurate CBF i changes in the presence of strong systemic physiology variations during a hypercapnia maneuver. Approach: Multi-layer slab and head-like realistic (curved) geometries were used to run MC simulations of photon propagation through the head. The simulation data were post-processed into models with variable extracerebral thicknesses and used to fit DCS multi-distance intensity autocorrelation measurements to estimate CBF i timecourses. The results of the MC CBF i values from a set of human subject hypercapnia sessions were compared with CBF i values estimated using a semi-infinite analytical model, as commonly used in the field. Results: Group averages indicate a gradual systemic increase in blood flow following a different temporal profile versus the expected rapid CBF response. Optimized MC models, guided by several intrinsic criteria and a pressure modulation maneuver, were able to more effectively separate CBF i changes from scalp blood flow influence than the analytical fitting, which assumed a homogeneous medium. Three-layer models performed better than two-layer ones; slab and curved models achieved largely similar results, though curved geometries were closer to physiological layer thicknesses. Conclusion: Three-layer, adjustable MC models can be useful in separating distinct changes in scalp and brain blood flow. Pressure modulation, along with reasonable estimates of physiological parameters, can help direct the choice of appropriate layer thicknesses in MC models.
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Affiliation(s)
- Melissa M. Wu
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Suk-Tak Chan
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Dibbyan Mazumder
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Davide Tamborini
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Kimberly A. Stephens
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Bin Deng
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Parya Farzam
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Joyce Yawei Chu
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Maria Angela Franceschini
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Jason Zhensheng Qu
- Massachusetts General Hospital, Harvard Medical School, Department of Anesthesia, Critical Care and Pain Medicine, Boston, Massachusetts, United States
| | - Stefan A. Carp
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
- Address all correspondence to Stefan A. Carp,
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10
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Milej D, Abdalmalak A, Rajaram A, St. Lawrence K. Direct assessment of extracerebral signal contamination on optical measurements of cerebral blood flow, oxygenation, and metabolism. NEUROPHOTONICS 2020; 7:045002. [PMID: 33062801 PMCID: PMC7540337 DOI: 10.1117/1.nph.7.4.045002] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 09/04/2020] [Indexed: 05/08/2023]
Abstract
Significance: Near-infrared spectroscopy (NIRS) combined with diffuse correlation spectroscopy (DCS) provides a noninvasive approach for monitoring cerebral blood flow (CBF), oxygenation, and oxygen metabolism. However, these methods are vulnerable to signal contamination from the scalp. Our work evaluated methods of reducing the impact of this contamination using time-resolved (TR) NIRS and multidistance (MD) DCS. Aim: The magnitude of scalp contamination was evaluated by measuring the flow, oxygenation, and metabolic responses to a global hemodynamic challenge. Contamination was assessed by collecting data with and without impeding scalp blood flow. Approach: Experiments involved healthy participants. A pneumatic tourniquet was used to cause scalp ischemia, as confirmed by contrast-enhanced NIRS, and a computerized gas system to generate a hypercapnic challenge. Results: Comparing responses acquired with and without the tourniquet demonstrated that the TR-NIRS technique could reduce scalp contributions in hemodynamic signals up to 4 times (r SD = 3 cm ) and 6 times (r SD = 4 cm ). Similarly, blood flow responses from the scalp and brain could be separated by analyzing MD DCS data with a multilayer model. Using these techniques, there was no change in metabolism during hypercapnia, as expected, despite large increases in CBF and oxygenation. Conclusion: NIRS/DCS can accurately monitor CBF and metabolism with the appropriate enhancement to depth sensitivity, highlighting the potential of these techniques for neuromonitoring.
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Affiliation(s)
- Daniel Milej
- Lawson Health Research Institute, Imaging Program, London, Ontario, Canada
- Western University, Department of Medical Biophysics, London, Ontario, Canada
| | - Androu Abdalmalak
- Lawson Health Research Institute, Imaging Program, London, Ontario, Canada
- Western University, Department of Medical Biophysics, London, Ontario, Canada
| | - Ajay Rajaram
- Lawson Health Research Institute, Imaging Program, London, Ontario, Canada
- Western University, Department of Medical Biophysics, London, Ontario, Canada
| | - Keith St. Lawrence
- Lawson Health Research Institute, Imaging Program, London, Ontario, Canada
- Western University, Department of Medical Biophysics, London, Ontario, Canada
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11
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Ko TS, Mavroudis CD, Baker WB, Morano VC, Mensah-Brown K, Boorady TW, Schmidt AL, Lynch JM, Busch DR, Gentile J, Bratinov G, Lin Y, Jeong S, Melchior RW, Rosenthal TM, Shade BC, Schiavo KL, Xiao R, Gaynor JW, Yodh AG, Kilbaugh TJ, Licht DJ. Non-invasive optical neuromonitoring of the temperature-dependence of cerebral oxygen metabolism during deep hypothermic cardiopulmonary bypass in neonatal swine. J Cereb Blood Flow Metab 2020; 40:187-203. [PMID: 30375917 PMCID: PMC6928559 DOI: 10.1177/0271678x18809828] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Management of deep hypothermic (DH) cardiopulmonary bypass (CPB), a critical neuroprotective strategy, currently relies on non-invasive temperature to guide cerebral metabolic suppression during complex cardiac surgery in neonates. Considerable inter-subject variability in temperature response and residual metabolism may contribute to the persisting risk for postoperative neurological injury. To characterize and mitigate this variability, we assess the sufficiency of conventional nasopharyngeal temperature (NPT) guidance, and in the process, validate combined non-invasive frequency-domain diffuse optical spectroscopy (FD-DOS) and diffuse correlation spectroscopy (DCS) for direct measurement of cerebral metabolic rate of oxygen (CMRO2). During CPB, n = 8 neonatal swine underwent cooling from normothermia to 18℃, sustained DH perfusion for 40 min, and then rewarming to simulate cardiac surgery. Continuous non-invasive and invasive measurements of intracranial temperature (ICT) and CMRO2 were acquired. Significant hysteresis (p < 0.001) between cooling and rewarming periods in the NPT versus ICT and NPT versus CMRO2 relationships were found. Resolution of this hysteresis in the ICT versus CMRO2 relationship identified a crucial insufficiency of conventional NPT guidance. Non-invasive CMRO2 temperature coefficients with respect to NPT (Q10 = 2.0) and ICT (Q10 = 2.5) are consistent with previous reports and provide further validation of FD-DOS/DCS CMRO2 monitoring during DH CPB to optimize management.
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Affiliation(s)
- Tiffany S Ko
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.,Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA.,Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Constantine D Mavroudis
- Division of Cardiovascular Surgery, Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Wesley B Baker
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Vincent C Morano
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
| | - Kobina Mensah-Brown
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Timothy W Boorady
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | | | - Jennifer M Lynch
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - David R Busch
- Department of Anesthesiology & Pain Management, University of Texas Southwestern, Dallas, TX, USA.,Department of Neurology & Neurotherapeutics, University of Texas Southwestern, Dallas, TX, USA
| | - Javier Gentile
- Division of Cardiothoracic Surgery, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - George Bratinov
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Yuxi Lin
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Sejin Jeong
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Richard W Melchior
- Department of Perfusion Services, Cardiac Center, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Tami M Rosenthal
- Department of Perfusion Services, Cardiac Center, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Brandon C Shade
- Department of Perfusion Services, Cardiac Center, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Kellie L Schiavo
- Department of Perfusion Services, Cardiac Center, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Rui Xiao
- Department of Pediatrics, Division of Biostatistics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - J William Gaynor
- Division of Cardiothoracic Surgery, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Arjun G Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
| | - Todd J Kilbaugh
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Daniel J Licht
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
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12
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Squair JW, Lee AHX, Sarafis ZK, Coombs G, Barak O, Cragg JJ, Mijacika T, Pecotic R, Krassioukov AV, Dogas Z, Dujic Z, Phillips AA. Sleep-disordered breathing is associated with brain vascular reactivity in spinal cord injury. Neurology 2019; 93:e2181-e2191. [PMID: 31694923 DOI: 10.1212/wnl.0000000000008619] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 06/20/2019] [Indexed: 01/01/2023] Open
Abstract
OBJECTIVE To determine the population-level odds of individuals with spinal cord injury (SCI) experiencing fatigue and sleep apnea, to elucidate relationships with level and severity of injury, and to examine associations with abnormal cerebrovascular responsiveness. METHODS We used population-level data, meta-analyses, and primary physiologic assessments to provide a large-scale integrated assessment of sleep-related complications after SCI. Population-level and meta-analyses included more than 60,000 able-bodied individuals and more than 1,800 individuals with SCI. Physiologic assessments were completed on a homogenous sample of individuals with cervical SCI and matched controls. We examined the prevalence of (1) self-reported chronic fatigue, (2) clinically identified sleep apnea, and 3) cerebrovascular responsiveness to changing CO2. RESULTS Logistic regression revealed a 7-fold elevated odds of chronic fatigue after SCI (odds ratio [OR] 7.9, 95% confidence interval [CI] 3.5-16.2), and that fatigue and trouble sleeping are correlated with the level and severity of injury. We further show that those with SCI experience elevated risk of clinically defined sleep-disordered breathing in more than 600 individuals with SCI (pooled OR 3.1, 95% CI 1.3-7.5). We confirmed that individuals with SCI experience a high rate of clinically defined sleep apnea using primary polysomnography assessments. We then provide evidence using syndromic analysis that sleep-disordered breathing is a factor strongly associated with impaired cerebrovascular responsiveness to CO2 in patients with SCI. CONCLUSIONS Individuals with SCI have an increased prevalence of sleep-disordered breathing, which may partially underpin their increased risk of stroke. There is thus a need to integrate sleep-related breathing examinations into routine care for individuals with SCI.
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Affiliation(s)
- Jordan W Squair
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia
| | - Amanda H X Lee
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia
| | - Zoe K Sarafis
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia
| | - Geoff Coombs
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia
| | - Otto Barak
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia
| | - Jacquelyn J Cragg
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia
| | - Tanja Mijacika
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia
| | - Renata Pecotic
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia
| | - Andrei V Krassioukov
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia
| | - Zoran Dogas
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia
| | - Zeljko Dujic
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia
| | - Aaron A Phillips
- From the Departments of Physiology and Pharmacology, Clinical Neurosciences, and Cardiac Sciences (J.W.S., A.A.P.), and Hotchkiss Brain Institute, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine (J.W.S., A.A.P.), University of Calgary; Centre for Heart, Lung and Vascular Health, Faculty of Health and Social Development (G.C.), University of British Columbia Okanagan, Kelowna; International Collaboration on Repair Discoveries (ICORD) (J.W.S., A.H.X.L., Z.K.S., J.J.C., A.V.K.), MD/PhD Training Program (J.W.S.), and Department of Experimental Medicine (J.W.S., A.H.X.L.), Faculty of Medicine, and Faculty of Pharmaceutical Sciences (J.J.C.), University of British Columbia, Vancouver, Canada; Department of Integrative Physiology (O.B., T.M., Z.D.) and Department of Neuroscience, Split Sleep Medicine Center (R.P., Z.D.), University of Split School of Medicine, Split, Croatia; and Department of Physiology (O.B.), University of Novi Sad Medical School, Serbia.
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Tabone L, Khirani S, Olmo Arroyo J, Amaddeo A, Sabil A, Fauroux B. Cerebral Oxygenation During Respiratory Events in Children with Sleep-Disordered Breathing and Associated Disorders. J Pediatr 2019; 214:134-140.e7. [PMID: 31540763 DOI: 10.1016/j.jpeds.2019.07.040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 06/12/2019] [Accepted: 07/12/2019] [Indexed: 11/16/2022]
Abstract
OBJECTIVES To evaluate changes in cerebral oxygenation by means of near-infrared spectroscopy during respiratory events in children with sleep-disordered breathing (SDB) and associated disorders. STUDY DESIGN Sixty-five children suspected of having SDB underwent a respiratory polygraphy with simultaneous recording of cerebral oxygenation indices. Respiratory events were analyzed by type of event, duration, variations of pulse oximetry (oxygen saturation [SpO2]), cerebral tissue oxygenation index (TOI), and heart rate. Data were categorized according to the severity of SDB and age. RESULTS There were 540 obstructive and mixed apneas, 172 central apneas, and 393 obstructive hypopneas analyzed. The mean decreases in SpO2 and TOI were 4.1 ± 3.1% and 3.4 ± 2.8%, respectively. The mean TOI decrease was significantly smaller for obstructive hypopnea compared with apneas. The TOI decrease was significantly less in children with mild SDB as compared with those with moderate-to-severe SDB and in children >7 years as compared with those <7 years old. TOI decreases correlated significantly with SpO2 decreases, duration of event, and age, regardless of the type of event. In a multivariable regression model, predictive factors of TOI decreases were the type of respiratory event, SpO2 decrease, apnea-hypopnea index, and age. CONCLUSIONS In children with SDB and associated disorders, cerebral oxygenation variations depend on the type of respiratory event, severity of SDB, and age.
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Affiliation(s)
- Laurence Tabone
- Research Unit French Institute of Health and Medical Research U 955, team 13, Créteil, France.
| | - Sonia Khirani
- Pediatric noninvasive ventilation and sleep unit, AP-HP, Necker Hospital, Paris, France; EA 7330 VIFASOM (Vigilance, Fatigue, Sleep and Public Health), Paris Descartes University, Paris, France; ASV Santé, Gennevilliers, France
| | - Jorge Olmo Arroyo
- Pediatric noninvasive ventilation and sleep unit, AP-HP, Necker Hospital, Paris, France
| | - Alessandro Amaddeo
- Pediatric noninvasive ventilation and sleep unit, AP-HP, Necker Hospital, Paris, France; EA 7330 VIFASOM (Vigilance, Fatigue, Sleep and Public Health), Paris Descartes University, Paris, France
| | | | - Brigitte Fauroux
- Pediatric noninvasive ventilation and sleep unit, AP-HP, Necker Hospital, Paris, France; EA 7330 VIFASOM (Vigilance, Fatigue, Sleep and Public Health), Paris Descartes University, Paris, France
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14
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Favilla CG, Forti RM, Zamzam A, Detre JA, Mullen MT, Yodh AG, Kasner SE, Busch DR, Baker WB, Mesquita RC, Kung D, Messé SR. Perfusion Enhancement with Respiratory Impedance After Stroke (PERI-Stroke). Neurotherapeutics 2019; 16:1296-1303. [PMID: 31140115 PMCID: PMC6985403 DOI: 10.1007/s13311-019-00744-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Intrathoracic pressure influences cardiac output and may affect cerebral blood flow (CBF). We aimed to quantify the cerebral hemodynamic response to intrathoracic pressure reduction in patients with acute ischemic stroke using a noninvasive respiratory impedance (RI) device. We assessed low-level (6 cm H2O) and high-level (12 cm H2O) RI in 17 spontaneously breathing patients within 72 h of anterior circulation acute ischemic stroke. Average age was 65 years, and 35% were female. Frontal lobe tissue perfusion and middle cerebral artery velocity (MCAv) were continuously monitored with optical diffuse correlation spectroscopy (DCS) and transcranial Doppler ultrasound, respectively. High-level RI resulted in a 7% increase in MCAv (p = 0.004). MCAv varied across all studied levels (baseline vs low-level vs high-level, p = 0.006), with a significant test of trend (p = 0.002). Changes were not seen in DCS measured tissue perfusion by nonparametric pairwise comparison. Mixed effects regression analysis identified a small increase in both MCAv (low-level RI: β 2.1, p < 0.001; high-level RI: β 5.0, p < 0.001) and tissue-level flow (low-level RI: β 5.4, p < 0.001; high-level RI: β 5.9, p < 0.001). There was a small increase in mean arterial pressure during low-level and high-level RI, 4% (p = 0.013) and 4% (p = 0.017), respectively. End-tidal CO2 remained stable throughout the protocol. RI was well tolerated. Manipulating intrathoracic pressure via noninvasive RI was safe and produced a small but measurable increase in cerebral perfusion in acute ischemic stroke patients. Future studies are warranted to assess whether RI is feasible and tolerable for prolonged use in hyperacute stroke management.
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Affiliation(s)
- Christopher G Favilla
- Department of Neurology, University of Pennsylvania, Philadelphia, USA.
- Department of Neurology, Hospital of the University of Pennsylvania, 3400 Spruce St, 3 West Gates, Philadelphia, PA, 19104-4283, USA.
| | - Rodrigo M Forti
- Department of Physics & Astronomy, University of Pennsylvania, Philadelphia, USA
- Institute of Physics, University of Campinas, Campinas, 13083-859, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology, Campinas, 13083-888, Brazil
| | - Ahmad Zamzam
- Department of Neurology, University of Pennsylvania, Philadelphia, USA
| | - John A Detre
- Department of Neurology, University of Pennsylvania, Philadelphia, USA
- Department of Radiology, University of Pennsylvania, Philadelphia, USA
| | - Michael T Mullen
- Department of Neurology, University of Pennsylvania, Philadelphia, USA
| | - Arjun G Yodh
- Department of Physics & Astronomy, University of Pennsylvania, Philadelphia, USA
| | - Scott E Kasner
- Department of Neurology, University of Pennsylvania, Philadelphia, USA
| | - David R Busch
- Department of Physics & Astronomy, University of Pennsylvania, Philadelphia, USA
- Department of Anesthesiology & Pain Management, University of Texas Southwestern, Dallas, USA
- Department Neurology & Neurotherapeutics, University of Texas Southwestern, Dallas, USA
| | - Wesley B Baker
- Department of Physics & Astronomy, University of Pennsylvania, Philadelphia, USA
- Department of Neurology, Children's Hospital of Philadelphia, Philadelphia, USA
| | - Rickson C Mesquita
- Institute of Physics, University of Campinas, Campinas, 13083-859, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology, Campinas, 13083-888, Brazil
| | - David Kung
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, USA
| | - Steven R Messé
- Department of Neurology, University of Pennsylvania, Philadelphia, USA
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15
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Portable Near-Infrared Technologies and Devices for Noninvasive Assessment of Tissue Hemodynamics. JOURNAL OF HEALTHCARE ENGINEERING 2019; 2019:3750495. [PMID: 30891170 PMCID: PMC6390246 DOI: 10.1155/2019/3750495] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 12/24/2018] [Accepted: 01/14/2019] [Indexed: 12/29/2022]
Abstract
Tissue hemodynamics, including the blood flow, oxygenation, and oxygen metabolism, are closely associated with many diseases. As one of the portable optical technologies to explore human physiology and assist in healthcare, near-infrared diffuse optical spectroscopy (NIRS) for tissue oxygenation measurement has been developed for four decades. In recent years, a dynamic NIRS technology, namely, diffuse correlation spectroscopy (DCS), has been emerging as a portable tool for tissue blood flow measurement. In this article, we briefly describe the basic principle and algorithms for static NIRS and dynamic NIRS (i.e., DCS). Then, we elaborate on the NIRS instrumentation, either commercially available or custom-made, as well as their applications to physiological studies and clinic. The extension of NIRS/DCS from spectroscopy to imaging was depicted, followed by introductions of advanced algorithms that were recently proposed. The future prospective of the NIRS/DCS and their feasibilities for routine utilization in hospital is finally discussed.
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16
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Impaired cerebral oxygenation and exercise tolerance in patients with severe obstructive sleep apnea syndrome. Sleep Med 2018; 51:37-46. [DOI: 10.1016/j.sleep.2018.06.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 06/25/2018] [Accepted: 06/27/2018] [Indexed: 11/19/2022]
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17
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Eichhorn L, Doerner J, Luetkens JA, Lunkenheimer JM, Dolscheid-Pommerich RC, Erdfelder F, Fimmers R, Nadal J, Stoffel-Wagner B, Schild HH, Hoeft A, Zur B, Naehle CP. Cardiovascular magnetic resonance assessment of acute cardiovascular effects of voluntary apnoea in elite divers. J Cardiovasc Magn Reson 2018; 20:40. [PMID: 29909774 PMCID: PMC6004697 DOI: 10.1186/s12968-018-0455-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 05/08/2018] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Prolonged breath holding results in hypoxemia and hypercapnia. Compensatory mechanisms help maintain adequate oxygen supply to hypoxia sensitive organs, but burden the cardiovascular system. The aim was to investigate human compensatory mechanisms and their effects on the cardiovascular system with regard to cardiac function and morphology, blood flow redistribution, serum biomarkers of the adrenergic system and myocardial injury markers following prolonged apnoea. METHODS Seventeen elite apnoea divers performed maximal breath-hold during cardiovascular magnetic resonance imaging (CMR). Two breath-hold sessions were performed to assess (1) cardiac function, myocardial tissue properties and (2) blood flow. In between CMR sessions, a head MRI was performed for the assessment of signs of silent brain ischemia. Urine and blood samples were analysed prior to and up to 4 h after the first breath-hold. RESULTS Mean breath-hold time was 297 ± 52 s. Left ventricular (LV) end-systolic, end-diastolic, and stroke volume increased significantly (p < 0.05). Peripheral oxygen saturation, LV ejection fraction, LV fractional shortening, and heart rate decreased significantly (p < 0.05). Blood distribution was diverted to cerebral regions with no significant changes in the descending aorta. Catecholamine levels, high-sensitivity cardiac troponin, and NT-pro-BNP levels increased significantly, but did not reach pathological levels. CONCLUSION Compensatory effects of prolonged apnoea substantially burden the cardiovascular system. CMR tissue characterisation did not reveal acute myocardial injury, indicating that the resulting cardiovascular stress does not exceed compensatory physiological limits in healthy subjects. However, these compensatory mechanisms could overly tax those limits in subjects with pre-existing cardiac disease. For divers interested in competetive apnoea diving, a comprehensive medical exam with a special focus on the cardiovascular system may be warranted. TRIAL REGISTRATION This prospective single-centre study was approved by the institutional ethics committee review board. It was retrospectively registered under ClinicalTrials.gov (Trial registration: NCT02280226 . Registered 29 October 2014).
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Affiliation(s)
- L. Eichhorn
- Department of Anaesthesiology and Intensive Care Medicine, University Hospital of Bonn, Bonn, Germany
| | - J. Doerner
- Department of Radiology, University Hospital of Bonn, Bonn, Germany
- Department of Radiology, University Hospital of Cologne, Cologne, Germany
| | - J. A. Luetkens
- Department of Radiology, University Hospital of Bonn, Bonn, Germany
| | | | | | - F. Erdfelder
- Department of Anaesthesiology and Intensive Care Medicine, University Hospital of Bonn, Bonn, Germany
| | - R. Fimmers
- Medical Biometry, Information Technology and Epidemiology, University of Bonn, Bonn, Germany
| | - J. Nadal
- Medical Biometry, Information Technology and Epidemiology, University of Bonn, Bonn, Germany
| | - B. Stoffel-Wagner
- Institute for Medical Biometry, Informatics and Epidemiology (IMBIE), Bonn, Germany
| | - H. H. Schild
- Department of Radiology, University Hospital of Bonn, Bonn, Germany
| | - A. Hoeft
- Department of Anaesthesiology and Intensive Care Medicine, University Hospital of Bonn, Bonn, Germany
| | - B. Zur
- Institute for Medical Biometry, Informatics and Epidemiology (IMBIE), Bonn, Germany
| | - C. P. Naehle
- Department of Radiology, University Hospital of Bonn, Bonn, Germany
- Department of Radiology, University Hospital of Cologne, Cologne, Germany
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18
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Tamanyan K, Walter LM, Weichard A, Davey MJ, Nixon GM, Biggs SN, Horne RSC. Age Effects on Cerebral Oxygenation and Behavior in Children with Sleep-disordered Breathing. Am J Respir Crit Care Med 2018; 197:1468-1477. [DOI: 10.1164/rccm.201709-1825oc] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Knarik Tamanyan
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Paediatrics, Monash University, Melbourne, Victoria, Australia; and
| | - Lisa M. Walter
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Paediatrics, Monash University, Melbourne, Victoria, Australia; and
| | - Aidan Weichard
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Paediatrics, Monash University, Melbourne, Victoria, Australia; and
| | - Margot J. Davey
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Paediatrics, Monash University, Melbourne, Victoria, Australia; and
- Melbourne Children’s Sleep Centre, Monash Children’s Hospital, Melbourne, Victoria, Australia
| | - Gillian M. Nixon
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Paediatrics, Monash University, Melbourne, Victoria, Australia; and
- Melbourne Children’s Sleep Centre, Monash Children’s Hospital, Melbourne, Victoria, Australia
| | - Sarah N. Biggs
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Paediatrics, Monash University, Melbourne, Victoria, Australia; and
| | - Rosemary S. C. Horne
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Paediatrics, Monash University, Melbourne, Victoria, Australia; and
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19
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Busch DR, Davis J, Kogler A, Galler RM, Parthasarathy AB, Yodh AG, Floyd TF. Laser safety in fiber-optic monitoring of spinal cord hemodynamics: a preclinical evaluation. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-9. [PMID: 29923371 PMCID: PMC8357330 DOI: 10.1117/1.jbo.23.6.065003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 05/30/2018] [Indexed: 05/02/2023]
Abstract
The prevention and treatment of spinal cord injury are focused upon the maintenance of spinal cord blood flow, yet no technology exists to monitor spinal cord ischemia. We recently demonstrated continuous monitoring of spinal cord ischemia with diffuse correlation and optical spectroscopies using an optical probe. Prior to clinical translation of this technology, it is critically important to demonstrate the safety profile of spinal cord exposure to the required light. To our knowledge, this is the first report of in situ safety testing of such a monitor. We expose the spinal cord to laser light utilizing a custom fiber-optic epidural probe in a survival surgery model (11 adult Dorset sheep). We compare the tissue illumination from our instrument with the American National Standards Institute maximum permissible exposures. We experimentally evaluate neurological and pathological outcomes of the irradiated sheep associated with prolonged exposure to the laser source and evaluate heating in ex vivo spinal cord samples. Spinal cord tissue was exposed to light levels at ∼18 × the maximum permissible exposure for the eye and ∼ ( 1 / 3 ) × for the skin. Multidisciplinary testing revealed no functional neurological sequelae, histopathologic evidence of laser-related injury to the spinal cord, or significant temperature changes in ex vivo samples. Low tissue irradiance and the lack of neurological, pathological, and temperature changes upon prolonged exposure to the laser source offer evidence that spinal cord tissues can be monitored safely with near-infrared optical probes placed within the epidural space.
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Affiliation(s)
- David R. Busch
- University of Texas Southwestern, Department of Anesthesiology and Pain Management, Dallas Texas, United States
- University of Texas Southwestern, Department of Neurology and Neurotherapeutics, Dallas, Texas, United States
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
- Address all correspondence to: David R. Busch, E-mail: ; Thomas F. Floyd, E-mail:
| | - James Davis
- Stony Brook University Medical Center, Department of Pathology, Stony Brook, New York, United States
| | - Angela Kogler
- Stony Brook University Medical Center, Department of Anesthesiology, Stony Brook, New York, United States
- Stony Brook University, Department of Biomedical Engineering, Stony Brook, New York, United States
| | - Robert M. Galler
- Stony Brook University Medical Center, Department of Neurosurgery, Stony Brook, New York, United States
| | - Ashwin B. Parthasarathy
- University of South Florida, Department of Electrical Engineering, Tampa, Florida, United States
| | - Arjun G. Yodh
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
| | - Thomas F. Floyd
- University of Texas Southwestern, Department of Anesthesiology and Pain Management, Dallas Texas, United States
- Address all correspondence to: David R. Busch, E-mail: ; Thomas F. Floyd, E-mail:
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20
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Gregori-Pla C, Cotta G, Blanco I, Zirak P, Giovannella M, Mola A, Fortuna A, Durduran T, Mayos M. Cerebral vasoreactivity in response to a head-of-bed position change is altered in patients with moderate and severe obstructive sleep apnea. PLoS One 2018. [PMID: 29538409 PMCID: PMC5851619 DOI: 10.1371/journal.pone.0194204] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Motivation Obstructive sleep apnea (OSA) can impair cerebral vasoreactivity and is associated with an increased risk of cerebrovascular disease. Unfortunately, an easy-to-use, non-invasive, portable monitor of cerebral vasoreactivity does not exist. Therefore, we have evaluated the use of near-infrared diffuse correlation spectroscopy to measure the microvascular cerebral blood flow (CBF) response to a mild head-of-bed position change as a biomarker for the evaluation of cerebral vasoreactivity alteration due to chronic OSA. Furthermore, we have monitored the effect of two years of continuous positive airway pressure (CPAP) treatment on the cerebral vasoreactivity. Methodology CBF was measured at different head-of-bed position changes (supine to 30° to supine) in sixty-eight patients with OSA grouped according to severity (forty moderate to severe, twenty-eight mild) and in fourteen control subjects without OSA. A subgroup (n = 13) with severe OSA was measured again after two years of CPAP treatment. Results All patients and controls showed a similar CBF response after changing position from supine to 30° (p = 0.819), with a median (confidence interval) change of -17.5 (-10.3, -22.9)%. However, when being tilted back to the supine position, while the control group (p = 0.091) and the mild patients with OSA (p = 0.227) recovered to the initial baseline, patients with moderate and severe OSA did not recover to the baseline (9.8 (0.8, 12.9)%, p < 0.001) suggesting altered cerebral vasoreactivity. This alteration was correlated with OSA severity defined by the apnea-hypopnea index, and with mean nocturnal arterial oxygen saturation. The CBF response was normalized after two years of CPAP treatment upon follow-up measurements. Conclusion In conclusion, microvascular CBF response to a head-of-bed challenge measured by diffuse correlation spectroscopy suggests that moderate and severe patients with OSA have altered cerebral vasoreactivity related to OSA severity. This may normalize after two years of CPAP treatment.
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Affiliation(s)
- Clara Gregori-Pla
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels (Barcelona), Spain
- * E-mail:
| | - Gianluca Cotta
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels (Barcelona), Spain
| | - Igor Blanco
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels (Barcelona), Spain
| | - Peyman Zirak
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels (Barcelona), Spain
| | - Martina Giovannella
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels (Barcelona), Spain
| | - Anna Mola
- Department of Respiratory Medicine, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Ana Fortuna
- Department of Respiratory Medicine, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Turgut Durduran
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels (Barcelona), Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Mercedes Mayos
- Department of Respiratory Medicine, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
- CIBER Enfermedades Respiratorias (CibeRes) (CB06/06), Madrid, Spain
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21
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Chen HL, Lin HC, Lu CH, Chen PC, Huang CC, Chou KH, Su MC, Friedman M, Chen YW, Lin WC. Systemic inflammation and alterations to cerebral blood flow in obstructive sleep apnea. J Sleep Res 2017; 26:789-798. [PMID: 28513057 DOI: 10.1111/jsr.12553] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 03/09/2017] [Indexed: 01/08/2023]
Abstract
Systemic inflammation and alterations to regional cerebral blood flow (CBF) have been reported previously in obstructive sleep apnea (OSA). This study utilized arterial spin labelling (ASL) perfusion magnetic resonance imaging (MRI) to evaluate CBF in OSA patients and determine its relationship with systemic inflammation. Twenty male patients with moderate and severe OSA [apnea-hypopnea index (AHI) >15] and 16 healthy male volunteers (AHI <5) were recruited. Early- or late-phase changes in leucocyte apoptosis and its subsets were determined by flow cytometry. Perfusion MRI data were acquired with a pulsed continuous ASL technique. The CBF maps were compared using voxel-based statistics to determine differences between the OSA and control groups. The differences in CBF, clinical severity and leucocyte apoptosis were correlated. Exploratory groupwise comparison between the two groups revealed that the OSA patients exhibited low CBF values in the vulnerable regions. The lower regional CBF values were correlated with higher clinical disease severity and leucocyte apoptosis. OSA impairs cerebral perfusion in vulnerable regions, and this deficit is associated with increased disease severity. The apparent correlation between systemic inflammation and cerebral perfusion may be indicative of haemodynamic alterations and their consequences in OSA.
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Affiliation(s)
- Hsiu-Ling Chen
- Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan.,Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Hsin-Ching Lin
- Department of Otolaryngology, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan.,Sleep Center, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Cheng-Hsien Lu
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan.,Department of Biological Science, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Pei-Chin Chen
- Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Chih-Cheng Huang
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Kun-Hsien Chou
- Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Mao-Chang Su
- Sleep Center, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.,Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Michael Friedman
- Division of Sleep Surgery, Department of Otolaryngology-Head and Neck Surgery, Rush University Medical Center, Chicago, IL, USA
| | - Yi-Wen Chen
- Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Wei-Che Lin
- Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan
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22
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Shang Y, Li T, Yu G. Clinical applications of near-infrared diffuse correlation spectroscopy and tomography for tissue blood flow monitoring and imaging. Physiol Meas 2017; 38:R1-R26. [PMID: 28199219 PMCID: PMC5726862 DOI: 10.1088/1361-6579/aa60b7] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Blood flow is one such available observable promoting a wealth of physiological insight both individually and in combination with other metrics. APPROACH Near-infrared diffuse correlation spectroscopy (DCS) and, to a lesser extent, diffuse correlation tomography (DCT), have increasingly received interest over the past decade as noninvasive methods for tissue blood flow measurements and imaging. DCS/DCT offers several attractive features for tissue blood flow measurements/imaging such as noninvasiveness, portability, high temporal resolution, and relatively large penetration depth (up to several centimeters). MAIN RESULTS This review first introduces the basic principle and instrumentation of DCS/DCT, followed by presenting clinical application examples of DCS/DCT for the diagnosis and therapeutic monitoring of diseases in a variety of organs/tissues including brain, skeletal muscle, and tumor. SIGNIFICANCE Clinical study results demonstrate technical versatility of DCS/DCT in providing important information for disease diagnosis and intervention monitoring.
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Affiliation(s)
- Yu Shang
- Key Laboratory of Instrumentation Science & Dynamic Measurement, North University of China, No.3 Xueyuan Road, Taiyuan, Shanxi 030051, China
| | - Ting Li
- State Key Lab Elect Thin Film & Integrated Device, University of Electronic Science & Technology of China, Chengdu, Sichuan 610054, China
| | - Guoqiang Yu
- Department of Biomedical Engineering, University of Kentucky, 514C RMB, 143 Graham Avenue, Lexington, KY 40506-0108, USA
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23
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Eichhorn L, Kessler F, Böhnert V, Erdfelder F, Reckendorf A, Meyer R, Ellerkmann RK. A Model to Simulate Clinically Relevant Hypoxia in Humans. J Vis Exp 2016. [PMID: 28060323 DOI: 10.3791/54933] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In case of apnea, arterial partial pressure of oxygen (pO2) decreases, while partial pressure of carbon dioxide (pCO2) increases. To avoid damage to hypoxia sensitive organs such as the brain, compensatory circulatory mechanisms help to maintain an adequate oxygen supply. This is mainly achieved by increased cerebral blood flow. Intermittent hypoxia is a commonly seen phenomenon in patients with obstructive sleep apnea. Acute airway obstruction can also result in hypoxia and hypercapnia. Until now, no adequate model has been established to simulate these dynamics in humans. Previous investigations focusing on human hypoxia used inhaled hypoxic gas mixtures. However, the resulting hypoxia was combined with hyperventilation and is therefore more representative of high altitude environments than of apnea. Furthermore, the transferability of previously performed animal experiments to humans is limited and the pathophysiological background of apnea induced physiological changes is poorly understood. In this study, healthy human apneic divers were utilized to mimic clinically relevant hypoxia and hypercapnia during apnea. Additionally, pulse-oximetry and Near Infrared Spectroscopy (NIRS) were used to evaluate changes in cerebral and peripheral oxygen saturation before, during, and after apnea.
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Affiliation(s)
- Lars Eichhorn
- Department of Anaesthesiology and Intensive Care Medicine, University Hospital of Bonn;
| | - Florian Kessler
- Department of Anaesthesiology and Intensive Care Medicine, University Hospital of Bonn
| | - Volker Böhnert
- Institute of Clinical Chemistry and Clinical Pharmacology, University of Bonn
| | - Felix Erdfelder
- Department of Anaesthesiology and Intensive Care Medicine, University Hospital of Bonn
| | - Anja Reckendorf
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover
| | | | - Richard K Ellerkmann
- Department of Anaesthesiology and Intensive Care Medicine, University Hospital of Bonn
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Busch DR, Rusin CG, Miller-Hance W, Kibler K, Baker WB, Heinle JS, Fraser CD, Yodh AG, Licht DJ, Brady KM. Continuous cerebral hemodynamic measurement during deep hypothermic circulatory arrest. BIOMEDICAL OPTICS EXPRESS 2016; 7:3461-3470. [PMID: 27699112 PMCID: PMC5030024 DOI: 10.1364/boe.7.003461] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 08/05/2016] [Accepted: 08/08/2016] [Indexed: 05/03/2023]
Abstract
While survival of children with complex congenital heart defects has improved in recent years, roughly half suffer neurological deficits suspected to be related to cerebral ischemia. Here we report the first demonstration of optical diffuse correlation spectroscopy (DCS) for continuous and non-invasive monitoring of cerebral microvascular blood flow during complex human neonatal or cardiac surgery. Comparison between DCS and Doppler ultrasound flow measurements during deep hypothermia, circulatory arrest, and rewarming were in good agreement. Looking forward, DCS instrumentation, alone and with NIRS, could provide access to flow and metabolic biomarkers needed by clinicians to adjust neuroprotective therapy during surgery.
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Affiliation(s)
- David R. Busch
- Division of Neurology, Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, PA, 19104, USA
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Craig G. Rusin
- Departments of Pediatrics and Cardiology, Baylor College of Medicine, Houston, TX, 77030 USA
| | - Wanda Miller-Hance
- Department of Pediatric Cardiovascular Anesthesiology, Baylor College of Medicine, Houston, TX, 77030 USA
| | - Kathy Kibler
- Department of Pediatrics, Texas Children’s Hospital, Houston, TX, 77030, USA
| | - Wesley B. Baker
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Anesthesiology and Critical Care, Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jeffrey S. Heinle
- Department of Surgery, Texas Children’s Hospital, Houston, TX, 77030, USA
| | - Charles D. Fraser
- Department of Surgery, Texas Children’s Hospital, Houston, TX, 77030, USA
| | - Arjun G. Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Daniel J. Licht
- Division of Neurology, Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, PA, 19104, USA
| | - Kenneth M. Brady
- Department of Anesthesiology, Baylor College of Medicine, Houston, TX, 77030, USA
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