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Highton D, Caldwell M, Tachtsidis I, Elwell CE, Smith M, Cooper CE. The influence of carbon dioxide on cerebral metabolism and oxygen consumption: combining multimodal monitoring with dynamic systems modelling. Biol Open 2024; 13:bio060087. [PMID: 38180242 PMCID: PMC10810564 DOI: 10.1242/bio.060087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 11/22/2023] [Indexed: 01/06/2024] Open
Abstract
Hypercapnia increases cerebral blood flow. The effects on cerebral metabolism remain incompletely understood although studies show an oxidation of cytochrome c oxidase, Complex IV of the mitochondrial respiratory chain. Systems modelling was combined with previously published non-invasive measurements of cerebral tissue oxygenation, cerebral blood flow, and cytochrome c oxidase redox state to evaluate any metabolic effects of hypercapnia. Cerebral tissue oxygen saturation and cytochrome oxidase redox state were measured with broadband near infrared spectroscopy and cerebral blood flow velocity with transcranial Doppler ultrasound. Data collected during 5-min hypercapnia in awake human volunteers were analysed using a Fick model to determine changes in brain oxygen consumption and a mathematical model of cerebral hemodynamics and metabolism (BrainSignals) to inform on mechanisms. Either a decrease in metabolic substrate supply or an increase in metabolic demand modelled the cytochrome oxidation in hypercapnia. However, only the decrease in substrate supply explained both the enzyme redox state changes and the Fick-calculated drop in brain oxygen consumption. These modelled outputs are consistent with previous reports of CO2 inhibition of mitochondrial succinate dehydrogenase and isocitrate dehydrogenase. Hypercapnia may have physiologically significant effects suppressing oxidative metabolism in humans and perturbing mitochondrial signalling pathways in health and disease.
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Affiliation(s)
- David Highton
- Neurocritical Care Unit, University College London Hospitals, National Hospital for Neurology & Neurosurgery, London WC1N 3BG, UK
- Princess Alexandra Hospital Southside Clinical Unit, University of Queensland, Brisbane QLD 4102, Australia
| | - Matthew Caldwell
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, UK
| | - Ilias Tachtsidis
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, UK
| | - Clare E. Elwell
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, UK
| | - Martin Smith
- Neurocritical Care Unit, University College London Hospitals, National Hospital for Neurology & Neurosurgery, London WC1N 3BG, UK
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, UK
| | - Chris E. Cooper
- School of Sport, Rehabilitation and Exercise Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
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2
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McDevitt WM, Farley M, Martin-Lamb D, Jones TJ, Morris KP, Seri S, Scholefield BR. Feasibility of non-invasive neuro-monitoring during extracorporeal membrane oxygenation in children. Perfusion 2023; 38:547-556. [PMID: 35212252 DOI: 10.1177/02676591211066804] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Detection of neurological complications during extracorporeal membrane oxygenation (ECMO) may be enhanced with non-invasive neuro-monitoring. We investigated the feasibility of non-invasive neuro-monitoring in a paediatric intensive care (PIC) setting. METHODS In a single centre, prospective cohort study we assessed feasibility of recruitment, and neuro-monitoring via somatosensory evoked potentials (SSEP), electroencephalography (EEG) and near infrared spectroscopy (NIRS) during venoarterial (VA) ECMO in paediatric patients (0-15 years). Measures were obtained within 24h of cannulation, during an intermediate period, and finally at decannulation or echo stress testing. SSEP/EEG/NIRS measures were correlated with neuro-radiology findings, and clinical outcome assessed via the Pediatric cerebral performance category (PCPC) scale 30 days post ECMO cannulation. RESULTS We recruited 14/20 (70%) eligible patients (median age: 9 months; IQR:4-54, 57% male) over an 18-month period, resulting in a total of 42 possible SSEP/EEG/NIRS measurements. Of these, 32/42 (76%) were completed. Missed recordings were due to lack of access/consent within 24 h of cannulation (5/42, 12%) or PIC death/discharge (5/42, 12%). In each patient, the majority of SSEP (8/14, 57%), EEG (8/14, 57%) and NIRS (11/14, 79%) test results were within normal limits. All patients with abnormal neuroradiology (4/10, 40%), and 6/7 (86%) with poor outcome (PCPC ≥4) developed indirect SSEP, EEG or NIRS measures of neurological complications prior to decannulation. No study-related adverse events or neuro-monitoring data interpreting issues were experienced. CONCLUSION Non-invasive neuro-monitoring (SSEP/EEG/NIRS) during ECMO is feasible and may provide early indication of neurological complications in this high-risk population.
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Affiliation(s)
- William M McDevitt
- Department of Neurophysiology, 156630Birmingham Children's Hospital Birmingham, UK
| | - Margaret Farley
- Paediatric Intensive Care Unit, 156630Birmingham Children's Hospital, Birmingham, UK
| | - Darren Martin-Lamb
- Department of Neurophysiology, 156630Birmingham Children's Hospital Birmingham, UK
| | - Timothy J Jones
- Department of Cardiac Surgery, 156630Birmingham Children's Hospital, Birmingham, UK.,Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
| | - Kevin P Morris
- Paediatric Intensive Care Unit, 156630Birmingham Children's Hospital, Birmingham, UK.,Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - Stefano Seri
- Department of Neurophysiology, 156630Birmingham Children's Hospital Birmingham, UK.,Aston Brain Centre, School of Life and Health Sciences, Aston University, Birmingham, UK
| | - Barnaby R Scholefield
- Paediatric Intensive Care Unit, 156630Birmingham Children's Hospital, Birmingham, UK.,Birmingham Acute Care Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
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Jiang S, Carpenter LL, Jiang H. Optical neuroimaging: advancing transcranial magnetic stimulation treatments of psychiatric disorders. Vis Comput Ind Biomed Art 2022; 5:22. [PMID: 36071259 PMCID: PMC9452613 DOI: 10.1186/s42492-022-00119-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 08/22/2022] [Indexed: 11/10/2022] Open
Abstract
Transcranial magnetic stimulation (TMS) has been established as an important and effective treatment for various psychiatric disorders. However, its effectiveness has likely been limited due to the dearth of neuronavigational tools for targeting purposes, unclear ideal stimulation parameters, and a lack of knowledge regarding the physiological response of the brain to TMS in each psychiatric condition. Modern optical imaging modalities, such as functional near-infrared spectroscopy and diffuse optical tomography, are promising tools for the study of TMS optimization and functional targeting in psychiatric disorders. They possess a unique combination of high spatial and temporal resolutions, portability, real-time capability, and relatively low costs. In this mini-review, we discuss the advent of optical imaging techniques and their innovative use in several psychiatric conditions including depression, panic disorder, phobias, and eating disorders. With further investment and research in the development of these optical imaging approaches, their potential will be paramount for the advancement of TMS treatment protocols in psychiatry.
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Gomez A, Sainbhi AS, Froese L, Batson C, Slack T, Stein KY, Cordingley DM, Mathieu F, Zeiler FA. The Quantitative Associations Between Near Infrared Spectroscopic Cerebrovascular Metrics and Cerebral Blood Flow: A Scoping Review of the Human and Animal Literature. Front Physiol 2022; 13:934731. [PMID: 35910568 PMCID: PMC9335366 DOI: 10.3389/fphys.2022.934731] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 06/09/2022] [Indexed: 11/13/2022] Open
Abstract
Cerebral blood flow (CBF) is an important physiologic parameter that is vital for proper cerebral function and recovery. Current widely accepted methods of measuring CBF are cumbersome, invasive, or have poor spatial or temporal resolution. Near infrared spectroscopy (NIRS) based measures of cerebrovascular physiology may provide a means of non-invasively, topographically, and continuously measuring CBF. We performed a systematically conducted scoping review of the available literature examining the quantitative relationship between NIRS-based cerebrovascular metrics and CBF. We found that continuous-wave NIRS (CW-NIRS) was the most examined modality with dynamic contrast enhanced NIRS (DCE-NIRS) being the next most common. Fewer studies assessed diffuse correlation spectroscopy (DCS) and frequency resolved NIRS (FR-NIRS). We did not find studies examining the relationship between time-resolved NIRS (TR-NIRS) based metrics and CBF. Studies were most frequently conducted in humans and animal studies mostly utilized large animal models. The identified studies almost exclusively used a Pearson correlation analysis. Much of the literature supported a positive linear relationship between changes in CW-NIRS based metrics, particularly regional cerebral oxygen saturation (rSO2), and changes in CBF. Linear relationships were also identified between other NIRS based modalities and CBF, however, further validation is needed.
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Affiliation(s)
- Alwyn Gomez
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- Section of Neurosurgery, Department of Surgery, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- *Correspondence: Alwyn Gomez,
| | - Amanjyot Singh Sainbhi
- Biomedical Engineering, Faculty of Engineering, University of Manitoba, Winnipeg, MB, Canada
| | - Logan Froese
- Biomedical Engineering, Faculty of Engineering, University of Manitoba, Winnipeg, MB, Canada
| | - Carleen Batson
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Trevor Slack
- Biomedical Engineering, Faculty of Engineering, University of Manitoba, Winnipeg, MB, Canada
| | - Kevin Y. Stein
- Biomedical Engineering, Faculty of Engineering, University of Manitoba, Winnipeg, MB, Canada
| | - Dean M. Cordingley
- Applied Health Sciences Program, University of Manitoba, Winnipeg, MB, Canada
- Pan Am Clinic Foundation, Winnipeg, MB, Canada
| | - Francois Mathieu
- Interdepartmental Division of Critical Care, Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Frederick A. Zeiler
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- Section of Neurosurgery, Department of Surgery, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- Biomedical Engineering, Faculty of Engineering, University of Manitoba, Winnipeg, MB, Canada
- Centre on Aging, University of Manitoba, Winnipeg, MB, Canada
- Division of Anaesthesia, Department of Medicine, Addenbrooke’s Hospital, University of Cambridge, Cambridge, MA, United Kingdom
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
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The Use of Supercontinuum Laser Sources in Biomedical Diffuse Optics: Unlocking the Power of Multispectral Imaging. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11104616] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Optical techniques based on diffuse optics have been around for decades now and are making their way into the day-to-day medical applications. Even though the physics foundations of these techniques have been known for many years, practical implementation of these technique were hindered by technological limitations, mainly from the light sources and/or detection electronics. In the past 20 years, the developments of supercontinuum laser (SCL) enabled to unlock some of these limitations, enabling the development of system and methodologies relevant for medical use, notably in terms of spectral monitoring. In this review, we focus on the use of SCL in biomedical diffuse optics, from instrumentation and methods developments to their use for medical applications. A total of 95 publications were identified, from 1993 to 2021. We discuss the advantages of the SCL to cover a large spectral bandwidth with a high spectral power and fast switching against the disadvantages of cost, bulkiness, and long warm up times. Finally, we summarize the utility of using such light sources in the development and application of diffuse optics in biomedical sciences and clinical applications.
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New Directions in Exercise Prescription: Is There a Role for Brain-Derived Parameters Obtained by Functional Near-Infrared Spectroscopy? Brain Sci 2020; 10:brainsci10060342. [PMID: 32503207 PMCID: PMC7348779 DOI: 10.3390/brainsci10060342] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/25/2020] [Accepted: 05/29/2020] [Indexed: 02/06/2023] Open
Abstract
In the literature, it is well established that regular physical exercise is a powerful strategy to promote brain health and to improve cognitive performance. However, exact knowledge about which exercise prescription would be optimal in the setting of exercise–cognition science is lacking. While there is a strong theoretical rationale for using indicators of internal load (e.g., heart rate) in exercise prescription, the most suitable parameters have yet to be determined. In this perspective article, we discuss the role of brain-derived parameters (e.g., brain activity) as valuable indicators of internal load which can be beneficial for individualizing the exercise prescription in exercise–cognition research. Therefore, we focus on the application of functional near-infrared spectroscopy (fNIRS), since this neuroimaging modality provides specific advantages, making it well suited for monitoring cortical hemodynamics as a proxy of brain activity during physical exercise.
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Weatherall A, Poynter E, Garner A, Lee A. Near-infrared spectroscopy monitoring in a pre-hospital trauma patient cohort: An analysis of successful signal collection. Acta Anaesthesiol Scand 2020; 64:117-123. [PMID: 31287156 DOI: 10.1111/aas.13444] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 06/16/2019] [Accepted: 06/18/2019] [Indexed: 11/29/2022]
Abstract
BACKGROUND Noninvasive monitoring of cerebral physiology could potentially guide pre-hospital management of patients with traumatic injuries. Near-infrared spectroscopy (NIRS) is one such modality but the consistency of monitoring performance remains unclear. This study assessed the proportion of successful signal collection during pre-hospital care. METHODS As part of a prospective observational study, an independent study observer placed three sensors for a Nonin 7610 NIRS device; two on the forehead and one on the forearm. NIRS records were analysed for time of adequate monitoring signal in each sensor (>70% of total pre-hospital time). We also compared pre-hospital scene and transport times for patients with or without NIRS monitoring. RESULTS Sixty-three patients with monitoring sensors applied were compared to 255 patients where no study observer was on board and 97 without NIRS monitoring for various reasons within the same time period. The proportion of pre-hospital time with successful monitoring (>70%) was 71.4% (45 of 63) for all three sensors, with at least two sensors functional in 90.4% (57 of 63). The median (interquartile range) scene time was 19 (11-23) minutes in patients with NIRS monitoring compared to 18 (11-27) minutes without NIRS monitoring (P = .570). There was no difference in the median (interquartile range) total pre-hospital time between patients with or without monitoring sensors (72 [59-89] versus 72 [59-80] minutes; P = .605). CONCLUSIONS In this pre-hospital observational feasibility study with dedicated personnel an acceptable proportion of measurement time was achieved in over 90% of monitored subjects. Addition of NIRS monitoring did not alter pre-hospital scene or transport times in this research setting.
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Affiliation(s)
- Andrew Weatherall
- CareFlight Northmead New South Wales Australia
- Discipline of Child and Adolescent Health, Faculty of Medicine and Health The University of Sydney Sydney New South Wales Australia
| | | | - Alan Garner
- CareFlight Northmead New South Wales Australia
| | - Anna Lee
- Department of Anaesthesia and Intensive Care The Chinese University of Hong Kong Sha Tin Hong Kong
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8
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Zaleski KL, Kussman BD. Near-Infrared Spectroscopy in Pediatric Congenital Heart Disease. J Cardiothorac Vasc Anesth 2019; 34:489-500. [PMID: 31582201 DOI: 10.1053/j.jvca.2019.08.048] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 08/07/2019] [Accepted: 08/27/2019] [Indexed: 12/13/2022]
Abstract
Near-infrared spectroscopy (NIRS) is widely used to monitor tissue oxygenation in the pediatric cardiac surgical population. Clinicians who use NIRS must understand the underlying measurement principles in order to interpret and use this monitoring modality appropriately. The aims of this narrative review are to provide a brief overview of NIRS technology, discuss the normative and critical values of cerebral and somatic tissue oxygen saturation and the interpretation of these values, present the clinical studies (and their limitations) of NIRS as a perioperative monitoring modality in the pediatric congenital heart disease population, and introduce the emerging and future applications of NIRS.
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Affiliation(s)
- Katherine L Zaleski
- Department of Anesthesiology, Perioperative, and Critical Care Medicine, Division of Cardiac Anesthesia, Boston Children's Hospital, Boston, MA.
| | - Barry D Kussman
- Department of Anesthesiology, Perioperative, and Critical Care Medicine, Division of Cardiac Anesthesia, Boston Children's Hospital, Boston, MA
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9
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Skowno JJ. Hemodynamic monitoring in children with heart disease: Overview of newer technologies. Paediatr Anaesth 2019; 29:467-474. [PMID: 30667124 DOI: 10.1111/pan.13590] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 12/26/2018] [Accepted: 01/14/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Justin J Skowno
- Department of Anaesthesia, The Children's Hospital at Westmead, Sydney, NSW, Australia.,Discipline of Child and Adolescent Health, Faculty of Medicine and Health, The University of Sydney, NSW, Australia
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10
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Nasr VG, Bergersen LT, Lin HM, Benni PB, Bernier RS, Anderson ME, Kussman BD. Validation of a Second-Generation Near-Infrared Spectroscopy Monitor in Children With Congenital Heart Disease. Anesth Analg 2019; 128:661-668. [DOI: 10.1213/ane.0000000000002796] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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11
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Bortfeld H. Functional near-infrared spectroscopy as a tool for assessing speech and spoken language processing in pediatric and adult cochlear implant users. Dev Psychobiol 2018; 61:430-443. [PMID: 30588618 DOI: 10.1002/dev.21818] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 11/04/2018] [Accepted: 11/16/2018] [Indexed: 11/11/2022]
Abstract
Much of what is known about the course of auditory learning in following cochlear implantation is based on behavioral indicators that users are able to perceive sound. Both prelingually deafened children and postlingually deafened adults who receive cochlear implants display highly variable speech and language processing outcomes, although the basis for this is poorly understood. To date, measuring neural activity within the auditory cortex of implant recipients of all ages has been challenging, primarily because the use of traditional neuroimaging techniques is limited by the implant itself. Functional near-infrared spectroscopy (fNIRS) is an imaging technology that works with implant users of all ages because it is non-invasive, compatible with implant devices, and not subject to electrical artifacts. Thus, fNIRS can provide insight into processing factors that contribute to variations in spoken language outcomes in implant users, both children and adults. There are important considerations to be made when using fNIRS, particularly with children, to maximize the signal-to-noise ratio and to best identify and interpret cortical responses. This review considers these issues, recent data, and future directions for using fNIRS as a tool to understand spoken language processing in children and adults who hear through a cochlear implant.
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Affiliation(s)
- Heather Bortfeld
- Psychological Sciences, University of California, Merced, Merced, California
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12
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Liu G, Guo Z, Sun X, Chai W, Qi L, Li H, Zheng J, Guo T, He Z, Zhang X, Zhu J, Luo Y. Monitoring of the Effect of Cerebral Autoregulation on Delayed Cerebral Ischemia in Patients with Aneurysmal Subarachnoid Hemorrhage. World Neurosurg 2018; 118:e269-e275. [DOI: 10.1016/j.wneu.2018.06.170] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 06/19/2018] [Accepted: 06/20/2018] [Indexed: 11/15/2022]
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13
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Nasr VG, Twite MD, Walker SG, Kussman BD, Motta P, Mittnacht AJC, Mossad EB. Selected 2017 Highlights in Congenital Cardiac Anesthesia. J Cardiothorac Vasc Anesth 2018; 32:1546-1555. [PMID: 29699846 DOI: 10.1053/j.jvca.2018.03.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Vivian G Nasr
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Boston, MA
| | - Mark D Twite
- Department of Anesthesiology, University of Colorado and Children's Hospital Colorado, Anschutz Medical Campus, Aurora, CO
| | - Scott G Walker
- Department of Anesthesiology, Indiana University School of Medicine, Riley Hospital for Children, Indianapolis, IN
| | - Barry D Kussman
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Boston, MA
| | - Pablo Motta
- Division of Pediatric Cardiovascular Anesthesia, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
| | - Alexander J C Mittnacht
- Department of Anesthesiology, Perioperative and Pain Medicine, the Icahn School of Medicine at Mount Sinai, New York, NY.
| | - Emad B Mossad
- Division of Pediatric Cardiovascular Anesthesia, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
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Kussman BD, Laussen PC, Benni PB, McGowan FX, McElhinney DB. Cerebral Oxygen Saturation in Children With Congenital Heart Disease and Chronic Hypoxemia. Anesth Analg 2017; 125:234-240. [PMID: 28514318 DOI: 10.1213/ane.0000000000002073] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Increased hemoglobin (Hb) concentration accompanying hypoxemia is a compensatory response to maintain tissue oxygen delivery. Near infrared spectroscopy (NIRS) is used clinically to detect abnormalities in the balance of cerebral tissue oxygen delivery and consumption, including in children with congenital heart disease (CHD). Although NIRS-measured cerebral tissue O2 saturation (ScO2) correlates with arterial oxygen saturation (SaO2), jugular bulb O2 saturation (SjbO2), and Hb, little data exist on the interplay between these factors and cerebral O2 extraction (COE). This study investigated the associations of ScO2 and ΔSaO2-ScO2 with SaO2 and Hb and verified the normal range of ScO2 in children with CHD. METHODS Children undergoing cardiac catheterization for CHD were enrolled in a calibration and validation study of the FORE-SIGHT NIRS monitor. Two pairs of simultaneous arterial and jugular bulb samples were drawn for co-oximetry, calculation of a reference ScO2 (REF CX), and estimation of COE. Pearson correlation and linear regression were used to determine relationships between O2 saturation parameters and Hb. Data were also analyzed according to diagnostic group defined as acyanotic (SaO2 ≥ 90%) and cyanotic (SaO2 < 90%). RESULTS Of 65 children studied, acceptable jugular bulb samples (SjbO2 absolute difference between samples ≤10%) were obtained in 57 (88%). The ΔSaO2-SjbO2, ΔSaO2-ScO2, and ΔSaO2-REF CX were positively correlated with SaO2 and negatively correlated with Hb (all P < .001). Although by diagnostic group ScO2 differed statistically (P = .002), values in the cyanotic patients were within the range considered normal (69% ± 6%). COE estimated by the difference between arterial and jugular bulb O2 content (ΔCaO2-CjbO2, mL O2/100 mL) was not different for cyanotic and acyanotic patients (P = .10), but estimates using ΔSaO2-SjbO2, ΔSaO2-ScO2, or ΔSaO2-ScO2/SaO2 were significantly different between the cyanotic and acyanotic children (P < .001). CONCLUSIONS Children with adequately compensated chronic hypoxemia appear to have ScO2 values within the normal range. The ΔSaO2-ScO2 is inversely related to Hb, with the implication that in the presence of reduced Hb, particularly if coupled with a decreased cardiac output, the ScO2 can fall to values associated with brain injury in laboratory studies.
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Affiliation(s)
- Barry D Kussman
- From the *Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Boston, Massachusetts; †Department of Critical Care Medicine, Hospital for Sick Children, Toronto, Ontario, Canada; ‡CAS Medical Systems Inc, Branford, Connecticut; §Department of Anesthesiology and Critical Care Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; and ‖Department of Cardiothoracic Surgery, Stanford Medical Center, Palo Alto, California
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15
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Ferradal SL, Yuki K, Vyas R, Ha CG, Yi F, Stopp C, Wypij D, Cheng HH, Newburger JW, Kaza AK, Franceschini MA, Kussman BD, Grant PE. Non-invasive Assessment of Cerebral Blood Flow and Oxygen Metabolism in Neonates during Hypothermic Cardiopulmonary Bypass: Feasibility and Clinical Implications. Sci Rep 2017; 7:44117. [PMID: 28276534 PMCID: PMC5343476 DOI: 10.1038/srep44117] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 02/02/2017] [Indexed: 02/01/2023] Open
Abstract
The neonatal brain is extremely vulnerable to injury during periods of hypoxia and/or ischemia. Risk of brain injury is increased during neonatal cardiac surgery, where pre-existing hemodynamic instability and metabolic abnormalities are combined with long periods of low cerebral blood flow and/or circulatory arrest. Our understanding of events associated with cerebral hypoxia-ischemia during cardiopulmonary bypass (CPB) remains limited, largely due to inadequate tools to quantify cerebral oxygen delivery and consumption non-invasively and in real-time. This pilot study aims to evaluate cerebral blood flow (CBF) and oxygen metabolism (CMRO2) intraoperatively in neonates by combining two novel non-invasive optical techniques: frequency-domain near-infrared spectroscopy (FD-NIRS) and diffuse correlation spectroscopy (DCS). CBF and CMRO2 were quantified before, during and after deep hypothermic cardiopulmonary bypass (CPB) in nine neonates. Our results show significantly decreased CBF and CMRO2 during hypothermic CPB. More interestingly, a change of coupling between both variables is observed during deep hypothermic CPB in all subjects. Our results are consistent with previous studies using invasive techniques, supporting the concept of FD-NIRS/DCS as a promising technology to monitor cerebral physiology in neonates providing the potential for individual optimization of surgical management.
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Affiliation(s)
- Silvina L Ferradal
- Fetal-Neonatal Neuroimaging &Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Koichi Yuki
- Department of Anesthesiology, Perioperative &Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Rutvi Vyas
- Fetal-Neonatal Neuroimaging &Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Christopher G Ha
- Fetal-Neonatal Neuroimaging &Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Francesca Yi
- Fetal-Neonatal Neuroimaging &Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Christian Stopp
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - David Wypij
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Henry H Cheng
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Jane W Newburger
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Aditya K Kaza
- Department of Cardiovascular Surgery, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Maria A Franceschini
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Barry D Kussman
- Department of Anesthesiology, Perioperative &Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - P Ellen Grant
- Fetal-Neonatal Neuroimaging &Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Dinish US, Wong CL, Sriram S, Ong WK, Balasundaram G, Sugii S, Olivo M. Diffuse Optical Spectroscopy and Imaging to Detect and Quantify Adipose Tissue Browning. Sci Rep 2017; 7:41357. [PMID: 28145475 PMCID: PMC5286412 DOI: 10.1038/srep41357] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 12/20/2016] [Indexed: 02/08/2023] Open
Abstract
Adipose (fat) tissue is a complex metabolic organ that is highly active and essential. In contrast to white adipose tissue (WAT), brown adipose tissue (BAT) is deemed metabolically beneficial because of its ability to burn calories through heat production. The conversion of WAT-resident adipocytes to “beige” or “brown-like” adipocytes has recently attracted attention. However, it typically takes a few days to analyze and confirm this browning of WAT through conventional molecular, biochemical, or histological methods. Moreover, accurate quantification of the overall browning process is not possible by any of these methods. In this context, we report the novel application of diffuse reflectance spectroscopy (DRS) and multispectral imaging (MSI) to detect and quantify the browning process in mice. We successfully demonstrated the time-dependent increase in browning of WAT, following its induction through β-adrenergic agonist injections. The results from these optical techniques were confirmed with those of standard molecular and biochemical assays, which measure gene and protein expression levels of UCP1 and PGC-1α, as well as with histological examinations. We envision that the reported optical methods can be developed into a fast, real time, cost effective and easy to implement imaging approach for quantification of the browning process in adipose tissue.
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Affiliation(s)
- U S Dinish
- Bio Optical Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore
| | - Chi Lok Wong
- Bio Optical Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore
| | - Sandhya Sriram
- Fat Metabolism and Stem Cell Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore
| | - Wee Kiat Ong
- Fat Metabolism and Stem Cell Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore
| | - Ghayathri Balasundaram
- Bio Optical Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore
| | - Shigeki Sugii
- Fat Metabolism and Stem Cell Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore.,Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore
| | - Malini Olivo
- Bio Optical Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore.,School of Physics, National University of Ireland Galway, Ireland
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Noninvasive Vascular Methods for Detection of Delayed Cerebral Ischemia After Subarachnoid Hemorrhage. J Clin Neurophysiol 2016; 33:260-7. [DOI: 10.1097/wnp.0000000000000271] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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18
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Saliba J, Bortfeld H, Levitin DJ, Oghalai JS. Functional near-infrared spectroscopy for neuroimaging in cochlear implant recipients. Hear Res 2016; 338:64-75. [PMID: 26883143 DOI: 10.1016/j.heares.2016.02.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 12/18/2015] [Accepted: 02/12/2016] [Indexed: 10/22/2022]
Abstract
Functional neuroimaging can provide insight into the neurobiological factors that contribute to the variations in individual hearing outcomes following cochlear implantation. To date, measuring neural activity within the auditory cortex of cochlear implant (CI) recipients has been challenging, primarily because the use of traditional neuroimaging techniques is limited in people with CIs. Functional near-infrared spectroscopy (fNIRS) is an emerging technology that offers benefits in this population because it is non-invasive, compatible with CI devices, and not subject to electrical artifacts. However, there are important considerations to be made when using fNIRS to maximize the signal to noise ratio and to best identify meaningful cortical responses. This review considers these issues, the current data, and future directions for using fNIRS as a clinical application in individuals with CIs. This article is part of a Special Issue entitled <Annual Reviews 2016>.
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Affiliation(s)
- Joe Saliba
- Department of Otolaryngology - Head and Neck Surgery, Stanford University, Stanford, CA 94305, USA; Department of Otolaryngology - Head and Neck Surgery, McGill University, 1001 Boul. Decarie, Montreal, QC, Canada
| | - Heather Bortfeld
- Psychological Sciences, University of California-Merced, 5200 North Lake Road, Merced, CA 95343, USA
| | - Daniel J Levitin
- Department of Psychology, McGill University, 1205 Avenue Penfield, H3A 1B1, Montreal, QC, Canada
| | - John S Oghalai
- Department of Otolaryngology - Head and Neck Surgery, Stanford University, Stanford, CA 94305, USA.
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Chen W, Wang X, Wang B, Wang Y, Zhang Y, Zhao H, Gao F. Lock-in-photon-counting-based highly-sensitive and large-dynamic imaging system for continuous-wave diffuse optical tomography. BIOMEDICAL OPTICS EXPRESS 2016; 7:499-511. [PMID: 26977358 PMCID: PMC4771467 DOI: 10.1364/boe.7.000499] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 12/21/2015] [Accepted: 01/13/2016] [Indexed: 05/25/2023]
Abstract
We implemented a novel lock-in photon-counting detection architecture that combines the ultra-high sensitivity of the photon-counting detection and the measurement parallelism of the lock-in technique. Based on this technique, a dual-wavelength simultaneous measurement continuous wave diffuse optical tomography system was developed with a configuration of 16 sources and 16 detectors that works in a tandem serial-to-parallel fashion. Methodology validation and performance assessment of the system were conducted using phantom experiments that demonstrate excellent measurement linearity, moderate-term system stability, robustness to noise and negligible inter-wavelength crosstalk. 2-D imaging experiments further validate high sensitivity of the lock-in photon-counting methodology as well as high reliability of the proposed system. The advanced detection principle can be adapted to achieving a fully parallelized instrumentation for the extended applications.
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Affiliation(s)
- Weiting Chen
- Collage of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Xin Wang
- Collage of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Bingyuan Wang
- Collage of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Yihan Wang
- Collage of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Yanqi Zhang
- Collage of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Huijuan Zhao
- Collage of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
| | - Feng Gao
- Collage of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
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20
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Yao P, Guo W, Sheng X, Zhang D, Zhu X. A portable multi-channel wireless NIRS device for muscle activity real-time monitoring. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2014:3719-22. [PMID: 25570799 DOI: 10.1109/embc.2014.6944431] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Near-infrared spectroscopy (NIRS) is a relative new technology in monitoring muscle oxygenation and hemo-dynamics. This paper presents a portable multi-channel wireless NIRS device for real-time monitoring of muscle activity. The NIRS sensor is designed miniaturized and modularized, to make multi-site monitoring convenient. Wireless communication is applied to data transmission avoiding of cumbersome wires and the whole system is highly integrated. Special care is taken to eliminate motion artifact when designing the NIRS sensor and attaching it to human skin. Besides, the system is designed with high sampling rate so as to monitor rapid oxygenation changes during muscle activities. Dark noise and long-term drift tests have been carried out, and the result indicates the device has a good performance of accuracy and stability. In vivo experiments including arterial occlusion and isometric voluntary forearm muscle contraction were performed, demonstrating the system has the ability to monitor muscle oxygenation parameters effectively even in exercise.
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21
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Molinari F, Joy Martis R, Acharya UR, Meiburger KM, De Luca R, Petraroli G, Liboni W. Empirical mode decomposition analysis of near-infrared spectroscopy muscular signals to assess the effect of physical activity in type 2 diabetic patients. Comput Biol Med 2015; 59:1-9. [PMID: 25658504 DOI: 10.1016/j.compbiomed.2015.01.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 01/12/2015] [Accepted: 01/13/2015] [Indexed: 12/25/2022]
Abstract
Type 2 diabetes is a metabolic disorder that may cause major problems to several physiological systems. Exercise has proven to be very effective in the prevention, management and improvement of this pathology in patients. Muscle metabolism is often studied with near-infrared spectroscopy (NIRS), a noninvasive technique that can measure changes in the concentration of oxygenated (O2Hb) and reduced hemoglobin (HHb) of tissues. These NIRS signals are highly non-stationary, non-Gaussian and nonlinear in nature. The empirical mode decomposition (EMD) is used as a nonlinear adaptive model to extract information present in the NIRS signals. NIRS signals acquired from the tibialis anterior muscle of controls and type 2 diabetic patients are processed by EMD to yield three intrinsic mode functions (IMF). The sample entropy (SE), fractal dimension (FD), and Hurst exponent (HE) are computed from these IMFs. Subjects are monitored at the beginning of the study and after one year of a physical training programme. Following the exercise programme, we observed an increase in the SE and FD and a decrease in the HE in all diabetic subjects. Our results show the influence of physical exercise program in improving muscle performance and muscle drive by the central nervous system in the patients. A multivariate analysis of variance performed at the end of the training programme also indicated that the NIRS metabolic patterns of controls and diabetic subjects are more similar than at the beginning of the study. Hence, the proposed EMD technique applied to NIRS signals may be very useful to gain a non-invasive understanding of the neuromuscular and vascular impairment in diabetic subjects.
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Affiliation(s)
- Filippo Molinari
- Biolab, Department of Electronics and Telecommunications, Politecnico di Torino, Torino, Italy.
| | - Roshan Joy Martis
- Department of Electronics and Communication Engineering, St. Joseph Engineering College, Mangalore, India
| | - U Rajendra Acharya
- Department of Electronics and Computer Engineering, Ngee Ann Polytechnic, Singapore 599489, Singapore; Department of Biomedical Engineering, SIM University, Singapore, Singapore
| | - Kristen M Meiburger
- Biolab, Department of Electronics and Telecommunications, Politecnico di Torino, Torino, Italy
| | - Riccardo De Luca
- Diabetes Health Districts 8-9-10 Diabetes Unit ASL TO1 di Torino, Torino, Italy
| | - Giuliana Petraroli
- Diabetes Health Districts 8-9-10 Diabetes Unit ASL TO1 di Torino, Torino, Italy
| | - William Liboni
- "Un passo insieme" ONLUS Foundation, Valdellatorre, Torino, Italy
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22
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Bale G, Mitra S, Meek J, Robertson N, Tachtsidis I. A new broadband near-infrared spectroscopy system for in-vivo measurements of cerebral cytochrome-c-oxidase changes in neonatal brain injury. BIOMEDICAL OPTICS EXPRESS 2014; 5:3450-66. [PMID: 25360364 PMCID: PMC4206316 DOI: 10.1364/boe.5.003450] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 08/15/2014] [Accepted: 08/22/2014] [Indexed: 05/02/2023]
Abstract
We present a novel lens-based broadband near-infrared spectroscopy system to simultaneously measure cerebral changes in tissue oxygenation and haemodynamics via estimation of the changes in haemoglobin concentration; in addition to oxygen utilization via the measurement of the oxidation state of cytochrome-c-oxidase (CCO). We demonstrate the use of the system in a cohort of 6 newborn infants with neonatal encephalopathy in the Neonatal Intensive Care Unit for continuous measurement periods of up to 5 days. NIRS data was collected from above the frontal lobe on the left and right hemispheres simultaneously with systemic data to allow multimodal data analysis. This allowed us to study the NIRS variables in response to global pathophysiological events and we focused our analysis to spontaneous oxygen desaturations. We identified changes from the NIRS variables during 236 oxygen desaturations from over 212 hours of data with a change from the baseline to nadir of -12 ± 3%. There was a consistent negative change in the Δ[HbD] (= oxygenated - deoxygenated haemoglobin) and Δ[oxCCO] measurements, mean decreases were 3.0 ± 1.7μM and 0.22 ± 0.11μM, and a positive change in the Δ[HbT] (= oxygenated + deoxygenated haemoglobin) measurements across all subjects, mean increase was 0.85 ± 0.58μM. We have shown with a feasibility study that the relationship between haemoglobin oxygenation changes and CCO oxidation changes during these desaturation events was significantly associated with a magnetic resonance spectroscopy (MRS)-measured biomarker of injury severity (r = 0.91, p<0.01).
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Affiliation(s)
- Gemma Bale
- Department of Medical Physics and Bioengineering, Malet Place Engineering Building, University College London, UK
| | - Subhabrata Mitra
- Institute for Women’s Health, University College London and Neonatal Unit, University College London Hospitals Trust, London, UK
| | - Judith Meek
- Institute for Women’s Health, University College London and Neonatal Unit, University College London Hospitals Trust, London, UK
| | - Nicola Robertson
- Institute for Women’s Health, University College London and Neonatal Unit, University College London Hospitals Trust, London, UK
| | - Ilias Tachtsidis
- Department of Medical Physics and Bioengineering, Malet Place Engineering Building, University College London, UK
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23
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Gunadi S, Leung TS, Elwell CE, Tachtsidis I. Spatial sensitivity and penetration depth of three cerebral oxygenation monitors. BIOMEDICAL OPTICS EXPRESS 2014; 5:2896-912. [PMID: 25401006 PMCID: PMC4230856 DOI: 10.1364/boe.5.002896] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 07/16/2014] [Accepted: 07/16/2014] [Indexed: 05/03/2023]
Abstract
The spatial sensitivities of NIRO-100, ISS Oximeter and TRS-20 cerebral oxygenation monitors are mapped using the local perturbation method to inform on their penetration depths and susceptibilities to superficial contaminations. The results show that TRS-20 has the deepest mean penetration depth and is less sensitive than the other monitors to a localized absorption change in the superficial layer. However, an integration time of more than five seconds is required by the TRS-20 to achieve an acceptable level of signal-to-noise ratio, which is the poorest amongst the monitors. With the exception of NIRO-100 continuous wave method, the monitors are not significantly responsive to layer-wide absorption change that occurs in the superficial layer.
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24
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Re-evaluation of the near infrared spectra of mitochondrial cytochrome c oxidase: Implications for non invasive in vivo monitoring of tissues. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1882-1891. [PMID: 25175349 PMCID: PMC4331044 DOI: 10.1016/j.bbabio.2014.08.005] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 08/19/2014] [Accepted: 08/21/2014] [Indexed: 11/23/2022]
Abstract
We re-determined the near infrared (NIR) spectral signatures (650–980 nm) of the different cytochrome c oxidase redox centres, in the process separating them into their component species. We confirm that the primary contributor to the oxidase NIR spectrum between 700 and 980 nm is cupric CuA, which in the beef heart enzyme has a maximum at 835 nm. The 655 nm band characterises the fully oxidised haem a3/CuB binuclear centre; it is bleached either when one or more electrons are added to the binuclear centre or when the latter is modified by ligands. The resulting ‘perturbed’ binuclear centre is also characterised by a previously unreported broad 715–920 nm band. The NIR spectra of certain stable liganded species (formate and CO), and the unstable oxygen reaction compounds P and F, are similar, suggesting that the latter may resemble the stable species electronically. Oxidoreduction of haem a makes no contribution either to the 835 nm maximum or the 715 nm band. Our results confirm the ability of NIRS to monitor the CuA centre of cytochrome oxidase activity in vivo, although noting some difficulties in precise quantitative interpretations in the presence of perturbations of the haem a3/CuB binuclear centre. The NIR spectrum of cytochrome oxidase was deconvoluted into its component species. The dominant feature between 700 and 980 nm was confirmed as the CuA chromophore. There was no significant contribution from the haem a iron centre. A new feature between 715 and 920 nm was assigned to the haem a3/CuB binuclear centre. Changes in concentrations of oxygen intermediates P and F may be measurable in vivo.
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25
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Optical imaging of brain activation in Gambian infants. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 812:263-269. [PMID: 24729242 DOI: 10.1007/978-1-4939-0620-8_35] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Abstract
We used optical topography (OT) to investigate cognitive function in infants in rural Gambia. Images of changes in oxyhaemoglobin and deoxyhaemoglobin concentrations were reconstructed using a multispectral algorithm which uses the finite element method (FEM) to model the propagation of light through scattering tissue using the diffusion equation. High quality OT data enabled us to reconstruct images with robust representation of haemodynamic changes. OT is a feasible neuroimage technology for this resource-poor setting.
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26
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Banerjee J, Aladangady N. Biomarkers to decide red blood cell transfusion in newborn infants. Transfusion 2014; 54:2574-82. [DOI: 10.1111/trf.12670] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Revised: 02/19/2014] [Accepted: 02/21/2014] [Indexed: 02/05/2023]
Affiliation(s)
- Jayanta Banerjee
- Homerton University Hospital NHS Foundation Trust; London UK
- Barts and the London School of Medicine and Dentistry, Queen Mary University of London; London UK
- The Portland Hospital for Women and Children; London UK
| | - Narendra Aladangady
- Homerton University Hospital NHS Foundation Trust; London UK
- Barts and the London School of Medicine and Dentistry, Queen Mary University of London; London UK
- SDMC Medical School and Hospital; Dharwad India
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Zhang L, Sun J, Sun B, Luo Q, Gong H. Studying hemispheric lateralization during a Stroop task through near-infrared spectroscopy-based connectivity. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:57012. [PMID: 24862561 DOI: 10.1117/1.jbo.19.5.057012] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 04/30/2014] [Indexed: 05/28/2023]
Abstract
ABSTRACT. Near-infrared spectroscopy (NIRS) is a developing and promising functional brain imaging technology. Developing data analysis methods to effectively extract meaningful information from collected data is the major bottleneck in popularizing this technology. In this study, we measured hemodynamic activity of the prefrontal cortex (PFC) during a color-word matching Stroop task using NIRS. Hemispheric lateralization was examined by employing traditional activation and novel NIRS-based connectivity analyses simultaneously. Wavelet transform coherence was used to assess intrahemispheric functional connectivity. Spearman correlation analysis was used to examine the relationship between behavioral performance and activation/functional connectivity, respectively. In agreement with activation analysis, functional connectivity analysis revealed leftward lateralization for the Stroop effect and correlation with behavioral performance. However, functional connectivity was more sensitive than activation for identifying hemispheric lateralization. Granger causality was used to evaluate the effective connectivity between hemispheres. The results showed increased information flow from the left to the right hemispheres for the incongruent versus the neutral task, indicating a leading role of the left PFC. This study demonstrates that the NIRS-based connectivity can reveal the functional architecture of the brain more comprehensively than traditional activation, helping to better utilize the advantages of NIRS.
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Affiliation(s)
- Lei Zhang
- Huazhong University of Science and Technology-Wuhan National Laboratory for Optoelectronics, Britton Chance Center for Biomedical Photonics, Wuhan 430074, ChinabHuazhong University of Science and Technology, Department of Biomedical Engineering, MoE Key L
| | - Jinyan Sun
- Huazhong University of Science and Technology-Wuhan National Laboratory for Optoelectronics, Britton Chance Center for Biomedical Photonics, Wuhan 430074, ChinabHuazhong University of Science and Technology, Department of Biomedical Engineering, MoE Key L
| | - Bailei Sun
- Huazhong University of Science and Technology-Wuhan National Laboratory for Optoelectronics, Britton Chance Center for Biomedical Photonics, Wuhan 430074, ChinabHuazhong University of Science and Technology, Department of Biomedical Engineering, MoE Key L
| | - Qingming Luo
- Huazhong University of Science and Technology-Wuhan National Laboratory for Optoelectronics, Britton Chance Center for Biomedical Photonics, Wuhan 430074, ChinabHuazhong University of Science and Technology, Department of Biomedical Engineering, MoE Key L
| | - Hui Gong
- Huazhong University of Science and Technology-Wuhan National Laboratory for Optoelectronics, Britton Chance Center for Biomedical Photonics, Wuhan 430074, ChinabHuazhong University of Science and Technology, Department of Biomedical Engineering, MoE Key L
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Monitoring cerebral oxygenation during balloon occlusion with multichannel NIRS. J Cereb Blood Flow Metab 2014; 34:347-56. [PMID: 24301292 PMCID: PMC3915216 DOI: 10.1038/jcbfm.2013.207] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 10/25/2013] [Accepted: 10/30/2013] [Indexed: 01/22/2023]
Abstract
We report on oxygenation changes noninvasively recorded by multichannel continuous-wave near infrared spectroscopy (CW-NIRS) during endovascular neuroradiologic interventions requiring temporary balloon occlusion of arteries supplying the cerebral circulation. Digital subtraction angiography (DSA) provides reference data on the site, timing, and effectiveness of the flow stagnation as well as on the amount and direction of collateral circulation. This setting allows us to relate CW-NIRS findings to brain specific perfusion changes. We focused our analysis on the transition from normal perfusion to vessel occlusion, i.e., before hypoxia becomes clinically apparent. The localization of the maximal response correlated either with the core (occlusion of the middle cerebral artery) or with the watershed areas (occlusion of the internal carotid artery) of the respective vascular territories. In one patient with clinically and angiographically confirmed insufficient collateral flow during carotid artery occlusion, the total hemoglobin concentration became significantly asymmetric, with decreased values in the ipsilateral watershed area and contralaterally increased values. Multichannel CW-NIRS monitoring might serve as an objective and early predictive marker of critical perfusion changes during interventions-to prevent hypoxic damage of the brain. It also might provide valuable human reference data on oxygenation changes as they typically occur during acute stroke.
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Molinari F, Acharya UR, Martis RJ, De Luca R, Petraroli G, Liboni W. Entropy analysis of muscular near-infrared spectroscopy (NIRS) signals during exercise programme of type 2 diabetic patients: quantitative assessment of muscle metabolic pattern. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2013; 112:518-528. [PMID: 24075080 DOI: 10.1016/j.cmpb.2013.08.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 08/27/2013] [Accepted: 08/30/2013] [Indexed: 06/02/2023]
Abstract
Diabetes mellitus (DM) is a metabolic disorder that is widely rampant throughout the world population these days. The uncontrolled DM may lead to complications of eye, heart, kidney and nerves. The most common type of diabetes is the type 2 diabetes or insulin-resistant DM. Near-infrared spectroscopy (NIRS) technology is widely used in non-invasive monitoring of physiological signals. Three types of NIRS signals are used in this work: (i) variation in the oxygenated haemoglobin (O2Hb) concentration, (ii) deoxygenated haemoglobin (HHb), and (iii) ratio of oxygenated over the sum of the oxygenated and deoxygenated haemoglobin which is defined as: tissue oxygenation index (TOI) to analyze the effect of exercise on diabetes subjects. The NIRS signal has the characteristics of non-linearity and non-stationarity. Hence, the very small changes in this time series can be efficiently extracted using higher order statistics (HOS) method. Hence, in this work, we have used sample and HOS entropies to analyze these NIRS signals. These computer aided techniques will assist the clinicians to diagnose and monitor the health accurately and easily without any inter or intra observer variability. Results showed that after a one-year of physical exercise programme, all diabetic subjects increased the sample entropy of the NIRS signals, thus revealing a better muscle performance and an improved recruitment by the central nervous system. Moreover, after one year of physical therapy, diabetic subjects showed a NIRS muscular metabolic pattern that was not distinguished from that of controls. We believe that sample and bispectral entropy analysis is need when the aim is to compare the inner structure of the NIRS signals during muscle contraction, particularly when dealing with neuromuscular impairments.
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Affiliation(s)
- Filippo Molinari
- Biolab, Department of Electronics and Telecommunications, Politecnico di Torino, Torino, Italy.
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30
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Matthews PM, Coatney R, Alsaid H, Jucker B, Ashworth S, Parker C, Changani K. Technologies: preclinical imaging for drug development. DRUG DISCOVERY TODAY. TECHNOLOGIES 2013; 10:e343-e350. [PMID: 24050130 DOI: 10.1016/j.ddtec.2012.04.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Preclinical imaging with magnetic resonance imaging (MRI), computerised tomography (CT), ultrasound (US), positron emission tomography (PET) or single-photon emission computed tomography (SPECT) enable non-invasive measures of tissue structure, function or metabolism in vivo. The technologies can add value to preclinical studies by enabling dynamic pharmacological observations on the same animal and because of possibilities for relatively direct clinical translation. Potential benefits from the application of preclinical imaging should be considered routinely in drug development.
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31
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Jackson PA, Kennedy DO. The application of near infrared spectroscopy in nutritional intervention studies. Front Hum Neurosci 2013; 7:473. [PMID: 23964231 PMCID: PMC3741577 DOI: 10.3389/fnhum.2013.00473] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 07/29/2013] [Indexed: 11/29/2022] Open
Abstract
Functional near infrared spectroscopy (NIRS) is a non-invasive optical imaging technique used to monitor cerebral blood flow (CBF) and by proxy neuronal activation. The use of NIRS in nutritional intervention studies is a relatively novel application of this technique, with only a small, but growing, number of trials published to date. These trials—in which the effects on CBF following administration of dietary components such as caffeine, polyphenols and omega-3 polyunsaturated fatty acids are assessed—have successfully demonstrated NIRS as a sensitive measure of change in hemodynamic response during cognitive tasks in both acute and chronic treatment intervention paradigms. The existent research in this area has been limited by the constraints of the technique itself however advancements in the measurement technology, paired with studies endeavoring increased sophistication in number and locations of channels over the head should render the use of NIRS in nutritional interventions particularly valuable in advancing our understanding of the effects of nutrients and dietary components on the brain.
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Affiliation(s)
- Philippa A Jackson
- Faculty of Health and Life Sciences, Brain, Performance and Nutrition Research Centre, Northumbria University Newcastle upon Tyne, UK
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32
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Everdell NL, Airantzis D, Kolvya C, Suzuki T, Elwell CE. A portable wireless near-infrared spatially resolved spectroscopy system for use on brain and muscle. Med Eng Phys 2013; 35:1692-7. [PMID: 23706504 DOI: 10.1016/j.medengphy.2013.04.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2012] [Revised: 04/19/2013] [Accepted: 04/22/2013] [Indexed: 10/26/2022]
Abstract
We have designed, built and successfully tested a prototype portable and wireless near-infrared spectroscopy system. It takes forward the well-established series of NIRO spectroscopy instruments made by Hamamatsu Photonics (Hamamatsu City, Japan). It uses an identical optical probe, and has a data acquisition rate of 10 Hz. It illuminates the tissue with laser diode sources at 3 wavelengths of 775, 810 and 850 nm, and detects the reflected light with 2 silicon photodiode detectors at 2 different separations, enabling spatially resolved spectroscopy to be performed. We have tested it with both in vitro and in vivo experiments to establish its basic functionality for use in studies of both brain and muscle.
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Affiliation(s)
- N L Everdell
- Department of Medical Physics and Bioengineering, University College London, Gower Street, London, WC1E 6BT, UK.
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Ghosh A, Elwell C, Smith M. Review article: cerebral near-infrared spectroscopy in adults: a work in progress. Anesth Analg 2012; 115:1373-83. [PMID: 23144435 DOI: 10.1213/ane.0b013e31826dd6a6] [Citation(s) in RCA: 182] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Near-infrared spectroscopy (NIRS) has potential as a noninvasive brain monitor across a spectrum of disorders. In the last decade, there has been a rapid expansion of clinical experience using NIRS to monitor cerebral oxygenation, and there is some evidence that NIRS-guided brain protection protocols might lead to a reduction in perioperative neurologic complications after cardiac surgery. However, there are no data to support the wider application of NIRS during routine surgery under general anesthesia, and its application in brain injury, where it might be expected to have a key monitoring role, is undefined. Although increasingly sophisticated apparatuses, including broadband and time-resolved spectroscopy systems, provide insights into the potential of NIRS to measure regional cerebral oxygenation, hemodynamics, and metabolism in real-time, these innovations have yet to translate into effective monitor-guided brain protection treatment strategies. NIRS has many potential advantages over other neuromonitoring techniques, but further investigation and technological advances are necessary before it can be introduced more widely into clinical practice.
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Affiliation(s)
- Arnab Ghosh
- Department of Neurocritical Care, Box 30, The National Hospital for Neurology and Neurosurgery, University College London Hospitals, Queen Square, London WC1N 3BGUK
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Hallacoglu B, Sassaroli A, Wysocki M, Guerrero-Berroa E, Schnaider Beeri M, Haroutunian V, Shaul M, Rosenberg IH, Troen AM, Fantini S. Absolute measurement of cerebral optical coefficients, hemoglobin concentration and oxygen saturation in old and young adults with near-infrared spectroscopy. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:081406-1. [PMID: 23224167 PMCID: PMC3412596 DOI: 10.1117/1.jbo.17.8.081406] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2012] [Revised: 03/13/2012] [Accepted: 03/22/2012] [Indexed: 05/19/2023]
Abstract
We present near-infrared spectroscopy measurement of absolute cerebral hemoglobin concentration and saturation in a large sample of 36 healthy elderly (mean age, 85 ± 6 years) and 19 young adults (mean age, 28 ± 4 years). Non-invasive measurements were obtained on the forehead using a commercially available multi-distance frequency-domain system and analyzed using a diffusion theory model for a semi-infinite, homogeneous medium with semi-infinite boundary conditions. Our study included repeat measurements, taken five months apart, on 16 elderly volunteers that demonstrate intra-subject reproducibility of the absolute measurements with cross-correlation coefficients of 0.9 for absorption coefficient (μa), oxy-hemoglobin concentration ([HbO2]), and total hemoglobin concentration ([HbT]), 0.7 for deoxy-hemoglobin concentration ([Hb]), 0.8 for hemoglobin oxygen saturation (StO2), and 0.7 for reduced scattering coefficient (μ's). We found significant differences between the two age groups. Compared to young subjects, elderly subjects had lower cerebral [HbO2], [Hb], [HbT], and StO2 by 10 ± 4 μM, 4 ± 3 μM, 14 ± 5 μM, and 6%±5%, respectively. Our results demonstrate the reliability and robustness of multi-distance near-infrared spectroscopy measurements based on a homogeneous model in the human forehead on a large sample of human subjects. Absolute, non-invasive optical measurements on the brain, such as those presented here, can significantly advance the development of NIRS technology as a tool for monitoring resting/basal cerebral perfusion, hemodynamics, oxygenation, and metabolism.
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Affiliation(s)
- Bertan Hallacoglu
- Tufts University, Department of Biomedical Engineering, 4 Colby St, Medford, MA 02155, USA.
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O’Sullivan TD, Cerussi AE, Cuccia DJ, Tromberg BJ. Diffuse optical imaging using spatially and temporally modulated light. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:071311. [PMID: 22894472 PMCID: PMC3607494 DOI: 10.1117/1.jbo.17.7.071311] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 06/28/2012] [Indexed: 05/18/2023]
Abstract
The authors describe the development of diffuse optical imaging (DOI) technologies, specifically the use of spatial and temporal modulation to control near infrared light propagation in thick tissues. We present theory and methods of DOI focusing on model-based techniques for quantitative, in vivo measurements of endogenous tissue absorption and scattering properties. We specifically emphasize the common conceptual framework of the scalar photon density wave for both temporal and spatial frequency-domain approaches. After presenting the history, theoretical foundation, and instrumentation related to these methods, we provide a brief review of clinical and preclinical applications from our research as well as our outlook on the future of DOI technology.
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Affiliation(s)
- Thomas D. O’Sullivan
- University of California, Irvine, Laser Microbeam and Medical Program (LAMMP), Beckman Laser Institute and Medical Clinic, Irvine, California
| | - Albert E. Cerussi
- University of California, Irvine, Laser Microbeam and Medical Program (LAMMP), Beckman Laser Institute and Medical Clinic, Irvine, California
| | | | - Bruce J. Tromberg
- University of California, Irvine, Laser Microbeam and Medical Program (LAMMP), Beckman Laser Institute and Medical Clinic, Irvine, California
- Address all correspondence to: Bruce J. Tromberg, University of California, Irvine, Beckman Laser Institute and Medical Clinic, 1002 Health Sciences Road, Irvine, California 92612. Tel: +949 824 8705; Fax: 949 824 8413; E-mail:
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Francony G, Bouzat P, Payen JF. [Near infrared spectroscopy monitoring in the neurointensive care]. ACTA ACUST UNITED AC 2012; 31:e133-6. [PMID: 22683164 DOI: 10.1016/j.annfar.2012.04.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Near infrared spectroscopy (NIRS) can noninvasively measure cerebral saturation in oxygen, that permits to estimate brain oxygenation and metabolism. This technique could be incorporated into a multimodal monitoring for severely brain-injured patients. This review presents the principles of NIRS, its limits, the main results from clinical studies and its perspectives. More clinical studies are needed before recommending the routine use of NIRS in the ICU.
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Affiliation(s)
- G Francony
- Pôle anesthésie-réanimation, hôpital Michallon, BP 217, 38043 Grenoble cedex 09, France.
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Ferrari M, Quaresima V. A brief review on the history of human functional near-infrared spectroscopy (fNIRS) development and fields of application. Neuroimage 2012; 63:921-35. [PMID: 22510258 DOI: 10.1016/j.neuroimage.2012.03.049] [Citation(s) in RCA: 1089] [Impact Index Per Article: 90.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 02/21/2012] [Accepted: 03/16/2012] [Indexed: 12/14/2022] Open
Abstract
This review is aimed at celebrating the upcoming 20th anniversary of the birth of human functional near-infrared spectroscopy (fNIRS). After the discovery in 1992 that the functional activation of the human cerebral cortex (due to oxygenation and hemodynamic changes) can be explored by NIRS, human functional brain mapping research has gained a new dimension. fNIRS or optical topography, or near-infrared imaging or diffuse optical imaging is used mainly to detect simultaneous changes in optical properties of the human cortex from multiple measurement sites and displays the results in the form of a map or image over a specific area. In order to place current fNIRS research in its proper context, this paper presents a brief historical overview of the events that have shaped the present status of fNIRS. In particular, technological progresses of fNIRS are highlighted (i.e., from single-site to multi-site functional cortical measurements (images)), introduction of the commercial multi-channel systems, recent commercial wireless instrumentation and more advanced prototypes.
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Affiliation(s)
- Marco Ferrari
- Department of Health Sciences, University of L'Aquila, L'Aquila, Italy.
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Elwell CE, Kolyva C. Making light work: illuminating the future of biomedical optics. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2011; 369:4355-4357. [PMID: 22006894 DOI: 10.1098/rsta.2011.0303] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Affiliation(s)
- Clare E Elwell
- Department of Medical Physics and Bioengineering, University College London, UK.
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