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Shahdadian S, Wang X, Liu H. Directed physiological networks in the human prefrontal cortex at rest and post transcranial photobiomodulation. Sci Rep 2024; 14:10242. [PMID: 38702415 PMCID: PMC11068774 DOI: 10.1038/s41598-024-59879-7] [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: 09/28/2023] [Accepted: 04/16/2024] [Indexed: 05/06/2024] Open
Abstract
Cerebral infra-slow oscillation (ISO) is a source of vasomotion in endogenic (E; 0.005-0.02 Hz), neurogenic (N; 0.02-0.04 Hz), and myogenic (M; 0.04-0.2 Hz) frequency bands. In this study, we quantified changes in prefrontal concentrations of oxygenated hemoglobin (Δ[HbO]) and redox-state cytochrome c oxidase (Δ[CCO]) as hemodynamic and metabolic activity metrics, and electroencephalogram (EEG) powers as electrophysiological activity, using concurrent measurements of 2-channel broadband near-infrared spectroscopy and EEG on the forehead of 22 healthy participants at rest. After preprocessing, the multi-modality signals were analyzed using generalized partial directed coherence to construct unilateral neurophysiological networks among the three neurophysiological metrics (with simplified symbols of HbO, CCO, and EEG) in each E/N/M frequency band. The links in these networks represent neurovascular, neurometabolic, and metabolicvascular coupling (NVC, NMC, and MVC). The results illustrate that the demand for oxygen by neuronal activity and metabolism (EEG and CCO) drives the hemodynamic supply (HbO) in all E/N/M bands in the resting prefrontal cortex. Furthermore, to investigate the effect of transcranial photobiomodulation (tPBM), we performed a sham-controlled study by delivering an 800-nm laser beam to the left and right prefrontal cortex of the same participants. After performing the same data processing and statistical analysis, we obtained novel and important findings: tPBM delivered on either side of the prefrontal cortex triggered the alteration or reversal of directed network couplings among the three neurophysiological entities (i.e., HbO, CCO, and EEG frequency-specific powers) in the physiological network in the E and N bands, demonstrating that during the post-tPBM period, both metabolism and hemodynamic supply drive electrophysiological activity in directed network coupling of the prefrontal cortex (PFC). Overall, this study revealed that tPBM facilitates significant modulation of the directionality of neurophysiological networks in electrophysiological, metabolic, and hemodynamic activities.
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Affiliation(s)
- Sadra Shahdadian
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Xinlong Wang
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Hanli Liu
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, 76019, USA.
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Leadley G, Austin T, Bale G. Review of measurements and imaging of cytochrome-c-oxidase in humans using near-infrared spectroscopy: an update. BIOMEDICAL OPTICS EXPRESS 2024; 15:162-184. [PMID: 38223181 PMCID: PMC10783912 DOI: 10.1364/boe.501915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 11/21/2023] [Indexed: 01/16/2024]
Abstract
This review examines advancements in the measurement and imaging of oxidized cytochrome-c-oxidase (oxCCO) using near-infrared spectroscopy (NIRS) in humans since 2016. A total of 34 published papers were identified, with a focus on both adult and neonate populations. The NIRS-derived oxCCO signal has been demonstrated to correlate with physiological parameters and hemodynamics. New instrumentation, such as systems that allow the imaging of changes of oxCCO with diffuse optical tomography or combine the oxCCO measurement with diffuse correlation spectroscopy measures of blood flow, have advanced the field in the past decade. However, variability in its response across different populations and paradigms and lack of standardization limit its potential as a reliable and valuable indicator of brain health. Future studies should address these issues to fulfill the vision of oxCCO as a clinical biomarker.
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Affiliation(s)
- Georgina Leadley
- Department of Paediatrics, University of Cambridge, UK
- Department of Engineering, University of Cambridge, UK
- Department of Medical Physics and Biomedical Engineering, UCL, UK
| | - Topun Austin
- Department of Paediatrics, University of Cambridge, UK
| | - Gemma Bale
- Department of Engineering, University of Cambridge, UK
- Department of Physics, University of Cambridge, UK
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Li NC, Ioussoufovitch S, Diop M. HyperTRCSS: A hyperspectral time-resolved compressive sensing spectrometer for depth-sensitive monitoring of cytochrome-c-oxidase and blood oxygenation. JOURNAL OF BIOMEDICAL OPTICS 2024; 29:015002. [PMID: 38269084 PMCID: PMC10807872 DOI: 10.1117/1.jbo.29.1.015002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 12/21/2023] [Accepted: 01/04/2024] [Indexed: 01/26/2024]
Abstract
Significance Hyperspectral time-resolved (TR) near-infrared spectroscopy offers the potential to monitor cytochrome-c-oxidase (oxCCO) and blood oxygenation in the adult brain with minimal scalp/skull contamination. We introduce a hyperspectral TR spectrometer that uses compressive sensing to minimize acquisition time without compromising spectral range or resolution and demonstrate oxCCO and blood oxygenation monitoring in deep tissue. Aim Develop a hyperspectral TR compressive sensing spectrometer and use it to monitor oxCCO and blood oxygenation in deep tissue. Approach Homogeneous tissue-mimicking phantom experiments were conducted to confirm the spectrometer's sensitivity to oxCCO and blood oxygenation. Two-layer phantoms were used to evaluate the spectrometer's sensitivity to oxCCO and blood oxygenation in the bottom layer through a 10 mm thick static top layer. Results The spectrometer was sensitive to oxCCO and blood oxygenation changes in the bottom layer of the two-layer phantoms, as confirmed by concomitant measurements acquired directly from the bottom layer. Measures of oxCCO and blood oxygenation by the spectrometer were highly correlated with "gold standard" measures in the homogeneous and two-layer phantom experiments. Conclusions The results show that the hyperspectral TR compressive sensing spectrometer is sensitive to changes in oxCCO and blood oxygenation in deep tissue through a thick static top layer.
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Affiliation(s)
- Natalie C. Li
- Western University, School of Biomedical Engineering, Faculty of Engineering, London, Ontario, Canada
| | - Seva Ioussoufovitch
- Western University, School of Biomedical Engineering, Faculty of Engineering, London, Ontario, Canada
| | - Mamadou Diop
- Western University, School of Biomedical Engineering, Faculty of Engineering, London, Ontario, Canada
- Western University, Schulich School of Medicine and Dentistry, Department of Medical Biophysics, London, Ontario, Canada
- Lawson Health Research Institute, Imaging Program, London, Ontario, Canada
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Sissons C, Saeed F, Carter C, Lee K, Kerr K, Shahdadian S, Liu H. Unilateral Mitochondrial-Hemodynamic Coupling and Bilateral Connectivity in the Prefrontal Cortices of Young and Older Healthy Adults. Bioengineering (Basel) 2023; 10:1336. [PMID: 38002460 PMCID: PMC10669330 DOI: 10.3390/bioengineering10111336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/02/2023] [Accepted: 11/09/2023] [Indexed: 11/26/2023] Open
Abstract
A recent study demonstrated that noninvasive measurements of cortical hemodynamics and metabolism in the resting human prefrontal cortex can facilitate quantitative metrics of unilateral mitochondrial-hemodynamic coupling and bilateral connectivity in infraslow oscillation frequencies in young adults. The infraslow oscillation includes three distinct vasomotions with endogenic (E), neurogenic (N), and myogenic (M) frequency bands. The goal of this study was to prove the hypothesis that there are significant differences between young and older adults in the unilateral coupling (uCOP) and bilateral connectivity (bCON) in the prefrontal cortex. Accordingly, we performed measurements from 24 older adults (67.2 ± 5.9 years of age) using the same two-channel broadband near-infrared spectroscopy (bbNIRS) setup and resting-state experimental protocol as those in the recent study. After quantification of uCOP and bCON in three E/N/M frequencies and statistical analysis, we demonstrated that older adults had significantly weaker bilateral hemodynamic connectivity but significantly stronger bilateral metabolic connectivity than young adults in the M band. Furthermore, older adults exhibited significantly stronger unilateral coupling on both prefrontal sides in all E/N/M bands, particularly with a very large effect size in the M band (>1.9). These age-related results clearly support our hypothesis and were well interpreted following neurophysiological principles. The key finding of this paper is that the neurophysiological metrics of uCOP and bCON are highly associated with age and may have the potential to become meaningful features for human brain health and be translatable for future clinical applications, such as the early detection of Alzheimer's disease.
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Affiliation(s)
- Claire Sissons
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Fiza Saeed
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Caroline Carter
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Kathy Lee
- School of Social Work, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Kristen Kerr
- School of Social Work, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Sadra Shahdadian
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Hanli Liu
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX 76019, USA
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Harvey-Jones K, Lange F, Verma V, Bale G, Meehan C, Avdic-Belltheus A, Hristova M, Sokolska M, Torrealdea F, Golay X, Parfentyeva V, Durduran T, Bainbridge A, Tachtsidis I, Robertson NJ, Mitra S. Early assessment of injury with optical markers in a piglet model of neonatal encephalopathy. Pediatr Res 2023; 94:1675-1683. [PMID: 37308684 PMCID: PMC10624614 DOI: 10.1038/s41390-023-02679-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/25/2023] [Accepted: 05/08/2023] [Indexed: 06/14/2023]
Abstract
BACKGROUND Opportunities for adjunct therapies with cooling in neonatal encephalopathy are imminent; however, robust biomarkers of early assessment are lacking. Using an optical platform of broadband near-infrared spectroscopy and diffuse correlation spectroscopy to directly measure mitochondrial metabolism (oxCCO), oxygenation (HbD), cerebral blood flow (CBF), we hypothesised optical indices early (1-h post insult) after hypoxia-ischaemia (HI) predicts insult severity and outcome. METHODS Nineteen newborn large white piglets underwent continuous neuromonitoring as controls or following moderate or severe HI. Optical indices were expressed as mean semblance (phase difference) and coherence (spectral similarity) between signals using wavelet analysis. Outcome markers included the lactate/N-acetyl aspartate (Lac/NAA) ratio at 6 h on proton MRS and TUNEL cell count. RESULTS CBF-HbD semblance (cerebrovascular dysfunction) correlated with BGT and white matter (WM) Lac/NAA (r2 = 0.46, p = 0.004, r2 = 0.45, p = 0.004, respectively), TUNEL cell count (r2 = 0.34, p = 0.02) and predicted both initial insult (r2 = 0.62, p = 0.002) and outcome group (r2 = 0.65 p = 0.003). oxCCO-HbD semblance (cerebral metabolic dysfunction) correlated with BGT and WM Lac/NAA (r2 = 0.34, p = 0.01 and r2 = 0.46, p = 0.002, respectively) and differentiated between outcome groups (r2 = 0.43, p = 0.01). CONCLUSION Optical markers of both cerebral metabolic and vascular dysfunction 1 h after HI predicted injury severity and subsequent outcome in a pre-clinical model. IMPACT This study highlights the possibility of using non-invasive optical biomarkers for early assessment of injury severity following neonatal encephalopathy, relating to the outcome. Continuous cot-side monitoring of these optical markers can be useful for disease stratification in the clinical population and for identifying infants who might benefit from future adjunct neuroprotective therapies beyond cooling.
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Affiliation(s)
| | - Frederic Lange
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Vinita Verma
- Institute for Women's Health, University College London, London, UK
| | - Gemma Bale
- Department of Engineering and Department of Physics, University of Cambridge, Cambridge, UK
| | | | | | - Mariya Hristova
- Institute for Women's Health, University College London, London, UK
| | - Magdalena Sokolska
- Medical Physics and Biomedical Engineering, University College London Hospital, London, UK
| | - Francisco Torrealdea
- Medical Physics and Biomedical Engineering, University College London Hospital, London, UK
| | - Xavier Golay
- Institute of Neurology, University College London, London, UK
| | - Veronika Parfentyeva
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels (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
| | - Alan Bainbridge
- Medical Physics and Biomedical Engineering, University College London Hospital, London, UK
| | - Ilias Tachtsidis
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | | | - Subhabrata Mitra
- Institute for Women's Health, University College London, London, UK.
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Shahdadian S, Wang X, Liu H. Directed physiological networks in the human prefrontal cortex at rest and post transcranial photobiomodulation. RESEARCH SQUARE 2023:rs.3.rs-3393702. [PMID: 37886539 PMCID: PMC10602070 DOI: 10.21203/rs.3.rs-3393702/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
Cerebral infra-slow oscillation (ISO) is a source of vasomotion in endogenic (E; 0.005-0.02 Hz), neurogenic (N; 0.02-0.04 Hz), and myogenic (M; 0.04-0.2 Hz) frequency bands. In this study, we quantified changes in prefrontal concentrations of oxygenated hemoglobin ( Δ [ H b O ] ) and redox-state cytochrome c oxidase ( Δ [ C C O ] ) as hemodynamic and metabolic activity metrics, and electroencephalogram (EEG) powers as electrophysiological activity, using concurrent measurements of 2-channel broadband near-infrared spectroscopy and EEG on the forehead of 22 healthy participants at rest. After preprocessing, the multi-modality signals were analyzed using generalized partial directed coherence to construct unilateral neurophysiological networks among the three neurophysiological metrics (with simplified symbols of HbO, CCO, and EEG) in each E/N/M frequency band. The links in these networks represent neurovascular, neurometabolic, and metabolicvascular coupling (NVC, NMC, and MVC). The results illustrate that the demand for oxygen by neuronal activity and metabolism (EEG and CCO) drives the hemodynamic supply (HbO) in all E/N/M bands in the resting prefrontal cortex. Furthermore, to investigate the effect of transcranial photobiomodulation (tPBM), we performed a sham-controlled study by delivering an 800-nm laser beam to the left and right prefrontal cortex of the same participants. After performing the same data processing and statistical analysis, we obtained novel and important findings: tPBM delivered on either side of the prefrontal cortex triggered the alteration or reversal of directed network couplings among the three neurophysiological entities (i.e., HbO, CCO, and EEG frequency-specific powers) in the physiological network in the E and N bands, demonstrating that during the post-tPBM period, both metabolism and hemodynamic supply drive electrophysiological activity in directed network coupling of the PFC. Overall, this study revealed that tPBM facilitates significant modulation of the directionality of neurophysiological networks in electrophysiological, metabolic, and hemodynamic activities.
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Butters E, Srinivasan S, O'Brien JT, Su L, Bale G. A promising tool to explore functional impairment in neurodegeneration: A systematic review of near-infrared spectroscopy in dementia. Ageing Res Rev 2023; 90:101992. [PMID: 37356550 DOI: 10.1016/j.arr.2023.101992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 06/15/2023] [Accepted: 06/22/2023] [Indexed: 06/27/2023]
Abstract
This systematic review aimed to evaluate previous studies which used near-infrared spectroscopy (NIRS) in dementia given its suitability as a diagnostic and investigative tool in this population. From 800 identified records which used NIRS in dementia and prodromal stages, 88 studies were evaluated which employed a range of tasks testing memory (29), word retrieval (24), motor (8) and visuo-spatial function (4), and which explored the resting state (32). Across these domains, dementia exhibited blunted haemodynamic responses, often localised to frontal regions of interest, and a lack of task-appropriate frontal lateralisation. Prodromal stages, such as mild cognitive impairment, revealed mixed results. Reduced cognitive performance accompanied by either diminished functional responses or hyperactivity was identified, the latter suggesting a compensatory response not present at the dementia stage. Despite clear evidence of alterations in brain oxygenation in dementia and prodromal stages, a consensus as to the nature of these changes is difficult to reach. This is likely partially due to the lack of standardisation in optical techniques and processing methods for the application of NIRS to dementia. Further studies are required exploring more naturalistic settings and a wider range of dementia subtypes.
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Affiliation(s)
- Emilia Butters
- Department of Electrical Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, UK; Department of Psychiatry, School of Clinical Medicine, University of Cambridge, Cambridge, UK.
| | - Sruthi Srinivasan
- Department of Electrical Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, UK
| | - John T O'Brien
- Department of Psychiatry, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Li Su
- Department of Psychiatry, School of Clinical Medicine, University of Cambridge, Cambridge, UK; Department of Neuroscience, University of Sheffield, 385a Glossop Rd, Broomhall, Sheffield S10 2HQ, UK
| | - Gemma Bale
- Department of Physics, University of Cambridge, 19 JJ Thomson Avenue, Cambridge CB3 0FA, UK
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Caramelo I, Coelho M, Rosado M, Cardoso CMP, Dinis A, Duarte CB, Grãos M, Manadas B. Biomarkers of hypoxic-ischemic encephalopathy: a systematic review. World J Pediatr 2023; 19:505-548. [PMID: 37084165 PMCID: PMC10199106 DOI: 10.1007/s12519-023-00698-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 01/31/2023] [Indexed: 04/22/2023]
Abstract
BACKGROUND Current diagnostic criteria for hypoxic-ischemic encephalopathy in the early hours lack objective measurement tools. Therefore, this systematic review aims to identify putative molecules that can be used in diagnosis in daily clinical practice (PROSPERO ID: CRD42021272610). DATA SOURCES Searches were performed in PubMed, Web of Science, and Science Direct databases until November 2020. English original papers analyzing samples from newborns > 36 weeks that met at least two American College of Obstetricians and Gynecologists diagnostic criteria and/or imaging evidence of cerebral damage were included. Bias was assessed by the Newcastle-Ottawa Scale. The search and data extraction were verified by two authors separately. RESULTS From 373 papers, 30 met the inclusion criteria. Data from samples collected in the first 72 hours were extracted, and increased serum levels of neuron-specific enolase and S100-calcium-binding protein-B were associated with a worse prognosis in newborns that suffered an episode of perinatal asphyxia. In addition, the levels of glial fibrillary acidic protein, ubiquitin carboxyl terminal hydrolase isozyme-L1, glutamic pyruvic transaminase-2, lactate, and glucose were elevated in newborns diagnosed with hypoxic-ischemic encephalopathy. Moreover, pathway analysis revealed insulin-like growth factor signaling and alanine, aspartate and glutamate metabolism to be involved in the early molecular response to insult. CONCLUSIONS Neuron-specific enolase and S100-calcium-binding protein-B are potential biomarkers, since they are correlated with an unfavorable outcome of hypoxic-ischemic encephalopathy newborns. However, more studies are required to determine the sensitivity and specificity of this approach to be validated for clinical practice.
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Affiliation(s)
- Inês Caramelo
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal
- PhD Programme in Experimental Biology and Biomedicine, Institute for Interdisciplinary Research (IIIUC), University of Coimbra, Casa Costa Alemão, 3030-789, Coimbra, Portugal
| | - Margarida Coelho
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal
- Chemistry Department, Faculty of Sciences and Technology, University of Coimbra, 3004-535, Coimbra, Portugal
| | - Miguel Rosado
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal
- PhD Programme in Experimental Biology and Biomedicine, Institute for Interdisciplinary Research (IIIUC), University of Coimbra, Casa Costa Alemão, 3030-789, Coimbra, Portugal
| | | | - Alexandra Dinis
- Pediatric Intensive Care Unit, Hospital Pediátrico, Centro Hospitalar E Universitário de Coimbra, 3000-075, Coimbra, Portugal
| | - Carlos B Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal
- Department of Life Sciences, University of Coimbra, 3001-401, Coimbra, Portugal
| | - Mário Grãos
- Biocant, Technology Transfer Association, 3060-197, Cantanhede, Portugal
| | - Bruno Manadas
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal.
- Institute for Interdisciplinary Research, University of Coimbra (IIIUC), 3030-789, Coimbra, Portugal.
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Mathew A, Hassan HW, Korostynska O, Westad F, Mota-Silva E, Menichetti L, Mirtaheri P. In Vivo Analysis of a Biodegradable Magnesium Alloy Implant in an Animal Model Using Near-Infrared Spectroscopy. SENSORS (BASEL, SWITZERLAND) 2023; 23:3063. [PMID: 36991774 PMCID: PMC10057053 DOI: 10.3390/s23063063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 02/26/2023] [Accepted: 02/28/2023] [Indexed: 06/19/2023]
Abstract
Biodegradable magnesium-based implants offer mechanical properties similar to natural bone, making them advantageous over nonbiodegradable metallic implants. However, monitoring the interaction between magnesium and tissue over time without interference is difficult. A noninvasive method, optical near-infrared spectroscopy, can be used to monitor tissue's functional and structural properties. In this paper, we collected optical data from an in vitro cell culture medium and in vivo studies using a specialized optical probe. Spectroscopic data were acquired over two weeks to study the combined effect of biodegradable Mg-based implant disks on the cell culture medium in vivo. Principal component analysis (PCA) was used for data analysis. In the in vivo study, we evaluated the feasibility of using the near-infrared (NIR) spectra to understand physiological events in response to magnesium alloy implantation at specific time points (Day 0, 3, 7, and 14) after surgery. Our results show that the optical probe can detect variations in vivo from biological tissues of rats with biodegradable magnesium alloy "WE43" implants, and the analysis identified a trend in the optical data over two weeks. The primary challenge of in vivo data analysis is the complexity of the implant interaction near the interface with the biological medium.
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Affiliation(s)
- Anna Mathew
- Faculty of Technology, Art and Design, Department of Mechanical, Electronic and Chemical Engineering, OsloMet—Oslo Metropolitan University, 0130 Oslo, Norway
| | - Hafiz Wajahat Hassan
- Faculty of Technology, Art and Design, Department of Mechanical, Electronic and Chemical Engineering, OsloMet—Oslo Metropolitan University, 0130 Oslo, Norway
| | - Olga Korostynska
- Faculty of Technology, Art and Design, Department of Mechanical, Electronic and Chemical Engineering, OsloMet—Oslo Metropolitan University, 0130 Oslo, Norway
| | - Frank Westad
- Department of Engineering Cybernetics, Norwegian University of Science and Technology, 7034 Trondheim, Norway
| | - Eduarda Mota-Silva
- Institute of Clinical Physiology, National Research Council (IFC-CNR), San Cataldo Research Area, 56124 Pisa, Italy
- Institute of Life Sciences, Sant’Anna School of Advanced Studies, 56127 Pisa, Italy
| | - Luca Menichetti
- Institute of Clinical Physiology, National Research Council (IFC-CNR), San Cataldo Research Area, 56124 Pisa, Italy
| | - Peyman Mirtaheri
- Faculty of Technology, Art and Design, Department of Mechanical, Electronic and Chemical Engineering, OsloMet—Oslo Metropolitan University, 0130 Oslo, Norway
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Déli É, Peters JF, Kisvárday Z. How the Brain Becomes the Mind: Can Thermodynamics Explain the Emergence and Nature of Emotions? ENTROPY (BASEL, SWITZERLAND) 2022; 24:1498. [PMID: 37420518 PMCID: PMC9601684 DOI: 10.3390/e24101498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 10/07/2022] [Accepted: 10/11/2022] [Indexed: 07/09/2023]
Abstract
The neural systems' electric activities are fundamental for the phenomenology of consciousness. Sensory perception triggers an information/energy exchange with the environment, but the brain's recurrent activations maintain a resting state with constant parameters. Therefore, perception forms a closed thermodynamic cycle. In physics, the Carnot engine is an ideal thermodynamic cycle that converts heat from a hot reservoir into work, or inversely, requires work to transfer heat from a low- to a high-temperature reservoir (the reversed Carnot cycle). We analyze the high entropy brain by the endothermic reversed Carnot cycle. Its irreversible activations provide temporal directionality for future orientation. A flexible transfer between neural states inspires openness and creativity. In contrast, the low entropy resting state parallels reversible activations, which impose past focus via repetitive thinking, remorse, and regret. The exothermic Carnot cycle degrades mental energy. Therefore, the brain's energy/information balance formulates motivation, sensed as position or negative emotions. Our work provides an analytical perspective of positive and negative emotions and spontaneous behavior from the free energy principle. Furthermore, electrical activities, thoughts, and beliefs lend themselves to a temporal organization, an orthogonal condition to physical systems. Here, we suggest that an experimental validation of the thermodynamic origin of emotions might inspire better treatment options for mental diseases.
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Affiliation(s)
- Éva Déli
- Department of Anatomy, Histology, and Embryology, University of Debrecen, 4032 Debrecen, Hungary
| | - James F. Peters
- Department of Electrical & Computer Engineering, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
- Department of Mathematics, Adiyaman University, Adiyaman 02040, Turkey
| | - Zoltán Kisvárday
- Department of Anatomy, Histology, and Embryology, University of Debrecen, 4032 Debrecen, Hungary
- ELKH Neuroscience Research Group, University of Debrecen, 4032 Debrecen, Hungary
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Optical Monitoring in Neonatal Seizures. Cells 2022; 11:cells11162602. [PMID: 36010678 PMCID: PMC9407001 DOI: 10.3390/cells11162602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 07/30/2022] [Accepted: 08/16/2022] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Neonatal seizures remain a significant cause of morbidity and mortality worldwide. The past decade has resulted in substantial progress in seizure detection and understanding the impact seizures have on the developing brain. Optical monitoring such as cerebral near-infrared spectroscopy (NIRS) and broadband NIRS can provide non-invasive continuous real-time monitoring of the changes in brain metabolism and haemodynamics. AIM To perform a systematic review of optical biomarkers to identify changes in cerebral haemodynamics and metabolism during the pre-ictal, ictal, and post-ictal phases of neonatal seizures. METHOD A systematic search was performed in eight databases. The search combined the three broad categories: (neonates) AND (NIRS) AND (seizures) using the stepwise approach following PRISMA guidance. RESULTS Fifteen papers described the haemodynamic and/or metabolic changes observed with NIRS during neonatal seizures. No randomised controlled trials were identified during the search. Studies reported various changes occurring in the pre-ictal, ictal, and post-ictal phases of seizures. CONCLUSION Clear changes in cerebral haemodynamics and metabolism were noted during the pre-ictal, ictal, and post-ictal phases of seizures in neonates. Further studies are necessary to determine whether NIRS-based methods can be used at the cot-side to provide clear pathophysiological data in real-time during neonatal seizures.
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Shahdadian S, Wang X, Kang S, Carter C, Chaudhari A, Liu H. Prefrontal cortical connectivity and coupling of infraslow oscillation in the resting human brain: a 2-channel broadband NIRS study. Cereb Cortex Commun 2022; 3:tgac033. [PMID: 36072711 PMCID: PMC9441674 DOI: 10.1093/texcom/tgac033] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Revised: 07/19/2022] [Accepted: 07/23/2022] [Indexed: 11/12/2022] Open
Abstract
The resting-state infraslow oscillation (ISO) of the cerebral cortex reflects the neurophysiological state of the human brain. ISO results from distinct vasomotion with endogenic (E), neurogenic (N), and myogenic (M) frequency bands. Quantification of prefrontal ISO in cortical hemodynamics and metabolism in the resting human brain may facilitate the identification of objective features that are characteristic of certain brain disorders. The goal of this study was to explore and quantify the prefrontal ISO of the cortical concentration changes of oxygenated hemoglobin (Δ[HbO]) and redox-state cytochrome c oxidase (Δ[CCO]) as hemodynamic and metabolic activity metrics in all 3 E/N/M bands. Two-channel broadband near-infrared spectroscopy (2-bbNIRS) enabled measurements of the forehead of 26 healthy young participants in a resting state once a week for 5 weeks. After quantifying the ISO spectral amplitude (SA) and coherence at each E/N/M band, several key and statistically reliable metrics were obtained as features: (i) SA of Δ[HbO] at all E/N/M bands, (ii) SA of Δ[CCO] in the M band, (iii) bilateral connectivity of hemodynamics and metabolism across the E and N bands, and (iv) unilateral hemodynamic-metabolic coupling in each of the E and M bands. These features have promising potential to be developed as objective biomarkers for clinical applications in the future.
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Affiliation(s)
- Sadra Shahdadian
- Department of Bioengineering, The University of Texas at Arlington, 500 UTA Blvd, Arlington, TX 76019, United States
| | - Xinlong Wang
- Department of Bioengineering, The University of Texas at Arlington, 500 UTA Blvd, Arlington, TX 76019, United States
| | - Shu Kang
- Department of Bioengineering, The University of Texas at Arlington, 500 UTA Blvd, Arlington, TX 76019, United States
| | - Caroline Carter
- Department of Bioengineering, The University of Texas at Arlington, 500 UTA Blvd, Arlington, TX 76019, United States
| | - Akhil Chaudhari
- Department of Bioengineering, The University of Texas at Arlington, 500 UTA Blvd, Arlington, TX 76019, United States
| | - Hanli Liu
- Department of Bioengineering, The University of Texas at Arlington, 500 UTA Blvd, Arlington, TX 76019, United States
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13
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Oh Y, Nguyen N, Jung HJ, Choe Y, Kim JG. Changes in Cytochrome C Oxidase Redox State and Hemoglobin Concentration in Rat Brain During 810 nm Irradiation Measured by Broadband Near-Infrared Spectroscopy. Photobiomodul Photomed Laser Surg 2022; 40:315-324. [DOI: 10.1089/photob.2021.0089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yoonho Oh
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Nam Nguyen
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Korea
| | | | | | - Jae Gwan Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Korea
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14
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Broadband-NIRS System Identifies Epileptic Focus in a Child with Focal Cortical Dysplasia—A Case Study. Metabolites 2022; 12:metabo12030260. [PMID: 35323703 PMCID: PMC8951122 DOI: 10.3390/metabo12030260] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/03/2022] [Accepted: 03/12/2022] [Indexed: 12/10/2022] Open
Abstract
Epileptic seizures are transiently occurring symptoms due to abnormal excessive or synchronous neuronal activity in the brain. Previous functional near-infrared spectroscopy (fNIRS) studies during seizures have focused in only monitoring the brain oxygenation and haemodynamic changes. However, few tools are available to measure actual cellular metabolism during seizures, especially at the bedside. Here we use an in-house developed multichannel broadband NIRS (or bNIRS) system, that, alongside the changes in oxy-, deoxy- haemoglobin concentration (HbO2, HHb), also quantifies the changes in oxidised cytochrome-c-oxidase Δ(oxCCO), a marker of cellular oxygen metabolism, simultaneously over 16 different brain locations. We used bNIRS to measure metabolic activity alongside brain tissue haemodynamics/oxygenation during 17 epileptic seizures at the bedside of a 3-year-old girl with seizures due to an extensive malformation of cortical development in the left posterior quadrant. Simultaneously Video-EEG data was recorded from 12 channels. Whilst we did observe the expected increase in brain tissue oxygenation (HbD) during seizures, it was almost diminished in the area of the focal cortical dysplasia. Furthermore, in the area of seizure origination (epileptic focus) ΔoxCCO decreased significantly at the time of seizure generalization when compared to the mean change in all other channels. We hypothesize that this indicates an incapacity to sustain and increase brain tissue metabolism during seizures in the region of the epileptic focus.
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15
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Photobiomodulation at Different Wavelengths Boosts Mitochondrial Redox Metabolism and Hemoglobin Oxygenation: Lasers vs. Light-Emitting Diodes In Vivo. Metabolites 2022; 12:metabo12020103. [PMID: 35208178 PMCID: PMC8880116 DOI: 10.3390/metabo12020103] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/17/2022] [Accepted: 01/19/2022] [Indexed: 12/13/2022] Open
Abstract
Our group previously examined 8 min photobiomodulation (PBM) by 1064 nm laser on the human forearm in vivo to determine its significant effects on vascular hemodynamics and cytochrome c oxidase redox activity. Since PBM uses a wide array of wavelengths, in this paper, we investigated (i) whether different wavelengths of lasers induced different PBM effects, and (ii) if a light-emitting diode (LED) at a similar wavelength to a laser could induce similar PBM effects. A broadband near-infrared spectroscopy (bbNIRS) system was utilized to assess concentration changes in oxygenated hemoglobin (Δ[HbO]) and oxidized cytochrome c oxidase (Δ[oxCCO]) during and after PBM with lasers at 800 nm, 850 nm, and 1064 nm, as well as a LED at 810 nm. Two groups of 10 healthy participants were measured before, during, and after active and sham PBM on their forearms. All results were tested for significance using repeated measures ANOVA. Our results showed that (i) lasers at all three wavelengths enabled significant increases in Δ[HbO] and Δ[oxCCO] of the human forearm while the 1064 nm laser sustained the increases longer, and that (ii) the 810-nm LED with a moderate irradiance (≈135 mW/cm2) induced measurable and significant rises in Δ[HbO] and Δ[oxCCO] with respect to the sham stimulation on the human forearm.
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16
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Wang X, Ma LC, Shahdadian S, Wu A, Truong NCD, Liu H. Metabolic Connectivity and Hemodynamic-Metabolic Coherence of Human Prefrontal Cortex at Rest and Post Photobiomodulation Assessed by Dual-Channel Broadband NIRS. Metabolites 2022; 12:42. [PMID: 35050164 PMCID: PMC8778041 DOI: 10.3390/metabo12010042] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/27/2021] [Accepted: 01/04/2022] [Indexed: 02/05/2023] Open
Abstract
Billions of neurons in the human brain form neural networks with oscillation rhythms. Infra-slow oscillation (ISO) presents three main physiological sources: endogenic, neurogenic, and myogenic vasomotions. Having an in vivo methodology for the absolute quantification of ISO from the human brain can facilitate the detection of brain abnormalities in cerebral hemodynamic and metabolic activities. In this study, we introduced a novel measurement-plus-analysis framework for the non-invasive quantification of prefrontal ISO by (1) taking dual-channel broadband near infrared spectroscopy (bbNIRS) measurements from 12 healthy humans during a 6-min rest and 4-min post transcranial photobiomodulation (tPBM) and (2) performing wavelet transform coherence (WTC) analysis on the measured time series data. The WTC indexes (IC, between 0 and 1) enabled the assessment of ipsilateral hemodynamic-metabolic coherence and bilateral functional connectivity in each ISO band of the human prefrontal cortex. At rest, bilateral hemodynamic connectivity was consistent across the three ISO bands (IC ≅ 0.66), while bilateral metabolic connectivity was relatively weaker. For post-tPBM/sham comparison, our analyses revealed three key findings: 8-min, right-forehead, 1064-nm tPBM (1) enhanced the amplitude of metabolic oscillation bilaterally, (2) promoted the bilateral metabolic connectivity of neurogenic rhythm, and (3) made the main effect on endothelial cells, causing alteration of hemodynamic-metabolic coherence on each side of the prefrontal cortex.
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Affiliation(s)
| | | | | | | | | | - Hanli Liu
- Department of Bioengineering, University of Texas at Arlington, 500 UTA Blvd, Arlington, TX 76019, USA; (X.W.); (L.-C.M.); (S.S.); (A.W.); (N.C.D.T.)
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17
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Pampín-Suárez S, Arce-Diego JL, Tapia O, Pérez-Campo FM, Rodríguez-Rey JC, Fanjul-Vélez F. Cytotoxicity analysis of oxazine 4-perchlorate fluorescence nerve potential clinical biomarker for guided surgery. BIOMEDICAL OPTICS EXPRESS 2021; 13:197-208. [DOI: 10.1364/boe.447773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 11/08/2021] [Indexed: 11/12/2022]
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18
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Hashem M, Wu Y, Dunn JF. Quantification of cytochrome c oxidase and tissue oxygenation using CW-NIRS in a mouse cerebral cortex. BIOMEDICAL OPTICS EXPRESS 2021; 12:7632-7656. [PMID: 35003857 PMCID: PMC8713667 DOI: 10.1364/boe.435532] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 10/06/2021] [Accepted: 11/05/2021] [Indexed: 05/05/2023]
Abstract
We provide a protocol for measuring the absolute concentration of the oxidized and reduced state of cytochrome c oxidase (CCO) in the cerebral cortex of mice, using broadband continuous-wave NIRS. The algorithm (NIR-AQUA) allows for absolute quantification of CCO and deoxyhemoglobin. Combined with an anoxia pulse, this also allows for quantification of total hemoglobin, and tissue oxygen saturation. CCO in the cortex was 4.9 ± 0.1 μM (mean ± SD, n=6). In normoxia, 84% of CCO was oxidized. We include hypoxia and cyanide validation studies to show CCO can be quantified independently to hemoglobin. This can be applied to study oxidative metabolism in the many rodent models of neurological disease.
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Affiliation(s)
- Mada Hashem
- Biomedical Engineering Graduate Program, University of Calgary, Calgary, Alberta, Canada T2N 4N1, Canada
- Department of Radiology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1, Canada
- Hotchkiss Brain Institute, University of Calgary, Alberta, Canada T2N 4N1, Canada
- Experimental Imaging Centre, Cumming School of Medicine, University of Calgary, Alberta, Canada T2N 4N1, Canada
| | - Ying Wu
- Department of Radiology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1, Canada
- Hotchkiss Brain Institute, University of Calgary, Alberta, Canada T2N 4N1, Canada
- Experimental Imaging Centre, Cumming School of Medicine, University of Calgary, Alberta, Canada T2N 4N1, Canada
| | - Jeff F. Dunn
- Department of Radiology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1, Canada
- Hotchkiss Brain Institute, University of Calgary, Alberta, Canada T2N 4N1, Canada
- Experimental Imaging Centre, Cumming School of Medicine, University of Calgary, Alberta, Canada T2N 4N1, Canada
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19
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Association between cerebral oxygen saturation and brain injury in neonates receiving therapeutic hypothermia for neonatal encephalopathy. J Perinatol 2021; 41:269-277. [PMID: 33462339 DOI: 10.1038/s41372-020-00910-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 10/16/2020] [Accepted: 12/01/2020] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To assess the association of cerebral oxygen saturation (CrSO2) collected by near infrared spectroscopy (NIRS) during therapeutic hypothermia (TH) and rewarming with evidence of brain injury on post-rewarming MRI. STUDY DESIGN This retrospective cohort study included 49 infants, who received TH for mild to severe neonatal encephalopathy. Of those, 26 presented with brain injury assessed by a novel MRI grading system, whereas 23 had normal MRI scans. RESULTS CrSO2 increased significantly from the first to the second day of TH in infants with brain injury, whereas it remained stable in patients with normal MRI. Increasing mean CrSO2 values during rewarming was associated with brain injury (aOR 1.14; 95% CI 1.00-1.28), specifically with gray matter (GM) injury (aOR 1.23; 95% CI 1.02-1.49). The area under the ROC curve showed an excellent discrimination for GM involvement. CONCLUSION Clinically applied NIRS during TH and rewarming can assist in identifying the risk for brain injury.
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20
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Kovacsova Z, Bale G, Mitra S, Lange F, Tachtsidis I. Absolute quantification of cerebral tissue oxygen saturation with multidistance broadband NIRS in newborn brain. BIOMEDICAL OPTICS EXPRESS 2021; 12:907-925. [PMID: 33680549 PMCID: PMC7901317 DOI: 10.1364/boe.412088] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/27/2020] [Accepted: 11/27/2020] [Indexed: 05/23/2023]
Abstract
Tissue oximetry with near-infrared spectroscopy (NIRS) is a technique for the measurement of absolute tissue oxygen saturation (StO2). Offering a real-time and non-invasive assessment of brain oxygenation and haemodynamics, StO2 has potential to be used for the assessment of newborn brain injury. Multiple algorithms have been developed to measure StO2, however, issues with low measurement accuracy or extracranial tissue signal contamination remain. In this work, we present a novel algorithm to recover StO2 in the neonate, broadband multidistance oximetry (BRUNO), based on a measurement of the gradient of attenuation against distance measured with broadband NIRS. The performance of the algorithm was compared to two other published algorithms, broadband fitting (BF) and spatially resolved spectroscopy (SRS). The median error when recovering StO2 in light transport simulations on a neonatal head mesh was 0.4% with BRUNO, 4.2% with BF and 9.5% with SRS. BRUNO was more sensitive to brain tissue oxygenation changes, shown in layered head model simulations. Comparison of algorithm performance during full oxygenation-deoxygenation cycles in a homogeneous dynamic blood phantom showed significant differences in the dynamic range of the algorithms; BRUNO recovered StO2 over 0-100%, BF over 0-90% and SRS over 39-80%. Recovering StO2 from data collected in a neonate treated at the neonatal intensive care showed different baseline values; mean StO2 was 64.9% with BRUNO, 67.2% with BF and 73.2% with SRS. These findings highlight the effect of StO2 algorithm selection on oxygenation recovery; applying BRUNO in the clinical care setting could reveal further insight into complex haemodynamic processes occurring during neonatal brain injury.
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Affiliation(s)
- Zuzana Kovacsova
- Department of Medical Physics & Biomedical Engineering, University College London, London, WC1E 6BT, UK
| | - Gemma Bale
- Department of Medical Physics & Biomedical Engineering, University College London, London, WC1E 6BT, UK
- Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, UK
- Department of Physics, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Subhabrata Mitra
- Institute for Women’s Health, University College London and Neonatal Unit, University College London Hospitals Trust, London, NW1 2BU, UK
| | - Frédéric Lange
- Department of Medical Physics & Biomedical Engineering, University College London, London, WC1E 6BT, UK
| | - Ilias Tachtsidis
- Department of Medical Physics & Biomedical Engineering, University College London, London, WC1E 6BT, UK
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21
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Afara IO, Shaikh R, Nippolainen E, Querido W, Torniainen J, Sarin JK, Kandel S, Pleshko N, Töyräs J. Characterization of connective tissues using near-infrared spectroscopy and imaging. Nat Protoc 2021; 16:1297-1329. [PMID: 33462441 DOI: 10.1038/s41596-020-00468-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 11/20/2020] [Indexed: 02/06/2023]
Abstract
Near-infrared (NIR) spectroscopy is a powerful analytical method for rapid, non-destructive and label-free assessment of biological materials. Compared to mid-infrared spectroscopy, NIR spectroscopy excels in penetration depth, allowing intact biological tissue assessment, albeit at the cost of reduced molecular specificity. Furthermore, it is relatively safe compared to Raman spectroscopy, with no risk of laser-induced photothermal damage. A typical NIR spectroscopy workflow for biological tissue characterization involves sample preparation, spectral acquisition, pre-processing and analysis. The resulting spectrum embeds intrinsic information on the tissue's biomolecular, structural and functional properties. Here we demonstrate the analytical power of NIR spectroscopy for exploratory and diagnostic applications by providing instructions for acquiring NIR spectra, maps and images in biological tissues. By adapting and extending this protocol from the demonstrated application in connective tissues to other biological tissues, we expect that a typical NIR spectroscopic study can be performed by a non-specialist user to characterize biological tissues in basic research or clinical settings. We also describe how to use this protocol for exploratory study on connective tissues, including differentiating among ligament types, non-destructively monitoring changes in matrix formation during engineered cartilage development, mapping articular cartilage proteoglycan content across bovine patella and spectral imaging across the depth-wise zones of articular cartilage and subchondral bone. Depending on acquisition mode and experiment objectives, a typical exploratory study can be completed within 6 h, including sample preparation and data analysis.
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Affiliation(s)
- Isaac O Afara
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.
- School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Queensland, Australia.
| | - Rubina Shaikh
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
- Diagnostic Imaging Centre, Kuopio University Hospital, Kuopio, Finland
| | - Ervin Nippolainen
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
| | - William Querido
- Department of Bioengineering, Temple University, Philadelphia, PA, USA
| | - Jari Torniainen
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
| | - Jaakko K Sarin
- Diagnostic Imaging Centre, Kuopio University Hospital, Kuopio, Finland
| | - Shital Kandel
- Department of Bioengineering, Temple University, Philadelphia, PA, USA
| | - Nancy Pleshko
- Department of Bioengineering, Temple University, Philadelphia, PA, USA
| | - Juha Töyräs
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
- School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Queensland, Australia
- Diagnostic Imaging Centre, Kuopio University Hospital, Kuopio, Finland
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22
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Neonatal NIRS monitoring: recommendations for data capture and review of analytics. J Perinatol 2021; 41:675-688. [PMID: 33589724 PMCID: PMC7883881 DOI: 10.1038/s41372-021-00946-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 11/20/2020] [Accepted: 01/19/2021] [Indexed: 01/29/2023]
Abstract
Brain injury is one of the most consequential problems facing neonates, with many preterm and term infants at risk for cerebral hypoxia and ischemia. To develop effective neuroprotective strategies, the mechanistic basis for brain injury must be understood. The fragile state of neonates presents unique research challenges; invasive measures of cerebral blood flow and oxygenation assessment exceed tolerable risk profiles. Near-infrared spectroscopy (NIRS) can safely and non-invasively estimate cerebral oxygenation, a correlate of cerebral perfusion, offering insight into brain injury-related mechanisms. Unfortunately, lack of standardization in device application, recording methods, and error/artifact correction have left the field fractured. In this article, we provide a framework for neonatal NIRS research. Our goal is to provide a rational basis for NIRS data capture and processing that may result in better comparability between studies. It is also intended to serve as a primer for new NIRS researchers and assist with investigation initiation.
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23
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Harvey-Jones K, Lange F, Tachtsidis I, Robertson NJ, Mitra S. Role of Optical Neuromonitoring in Neonatal Encephalopathy-Current State and Recent Advances. Front Pediatr 2021; 9:653676. [PMID: 33898363 PMCID: PMC8062863 DOI: 10.3389/fped.2021.653676] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 03/15/2021] [Indexed: 11/19/2022] Open
Abstract
Neonatal encephalopathy (NE) in term and near-term infants is a significant global health problem; the worldwide burden of disease remains high despite the introduction of therapeutic hypothermia. Assessment of injury severity and effective management in the neonatal intensive care unit (NICU) relies on multiple monitoring modalities from systemic to brain-specific. Current neuromonitoring tools provide information utilized for seizure management, injury stratification, and prognostication, whilst systemic monitoring ensures multi-organ dysfunction is recognized early and supported wherever needed. The neuromonitoring technologies currently used in NE however, have limitations in either their availability during the active treatment window or their reliability to prognosticate and stratify injury confidently in the early period following insult. There is therefore a real need for a neuromonitoring tool that provides cot side, early and continuous monitoring of brain health which can reliably stratify injury severity, monitor response to current and emerging treatments, and prognosticate outcome. The clinical use of near-infrared spectroscopy (NIRS) technology has increased in recent years. Research studies within this population have also increased, alongside the development of both instrumentation and signal processing techniques. Increasing use of commercially available cerebral oximeters in the NICU, and the introduction of advanced optical measurements using broadband NIRS (BNIRS), frequency domain NIRS (FDNIRS), and diffuse correlation spectroscopy (DCS) have widened the scope by allowing the direct monitoring of oxygen metabolism and cerebral blood flow, both key to understanding pathophysiological changes and predicting outcome in NE. This review discusses the role of optical neuromonitoring in NE and why this modality may provide the next significant piece of the puzzle toward understanding the real time state of the injured newborn brain.
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Affiliation(s)
- Kelly Harvey-Jones
- Neonatology, EGA Institute for Women's Health, University College London, London, United Kingdom
| | - Frederic Lange
- Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Ilias Tachtsidis
- Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Nicola J Robertson
- Neonatology, EGA Institute for Women's Health, University College London, London, United Kingdom.,Edinburgh Neuroscience & Centre for Clinical Brain Sciences, The University of Edinburgh, Edinburgh, United Kingdom
| | - Subhabrata Mitra
- Neonatology, EGA Institute for Women's Health, University College London, London, United Kingdom
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24
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Russell-Buckland J, Kaynezhad P, Mitra S, Bale G, Bauer C, Lingam I, Meehan C, Avdic-Belltheus A, Martinello K, Bainbridge A, Robertson NJ, Tachtsidis I. Systems Biology Model of Cerebral Oxygen Delivery and Metabolism During Therapeutic Hypothermia: Application to the Piglet Model. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1269:31-38. [PMID: 33966191 DOI: 10.1007/978-3-030-48238-1_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Hypoxic ischaemic encephalopathy (HIE) is a significant cause of death and disability. Therapeutic hypothermia (TH) is the only available standard of treatment, but 45-55% of cases still result in death or neurodevelopmental disability following TH. This work has focussed on developing a new brain tissue physiology and biochemistry systems biology model that includes temperature effects, as well as a Bayesian framework for analysis of model parameter estimation. Through this, we can simulate the effects of temperature on brain tissue oxygen delivery and metabolism, as well as analyse clinical and experimental data to identify mechanisms to explain differing behaviour and outcome. Presented here is an application of the model to data from two piglets treated with TH following hypoxic-ischaemic injury showing different responses and outcome following treatment. We identify the main mechanism for this difference as the Q10 temperature coefficient for metabolic reactions, with the severely injured piglet having a median posterior value of 0.133 as opposed to the mild injury value of 5.48. This work demonstrates the use of systems biology models to investigate underlying mechanisms behind the varying response to hypothermic treatment.
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Affiliation(s)
- Joshua Russell-Buckland
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK.
| | - P Kaynezhad
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - S Mitra
- Institute for Women's Health, University College London, London, UK
| | - G Bale
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - C Bauer
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - I Lingam
- Institute for Women's Health, University College London, London, UK
| | - C Meehan
- Institute for Women's Health, University College London, London, UK
| | | | - K Martinello
- Institute for Women's Health, University College London, London, UK
| | - A Bainbridge
- Department of Medical Physics and Biomedical Engineering, University College London Hospital, London, UK
| | - N J Robertson
- Institute for Women's Health, University College London, London, UK
| | - I Tachtsidis
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
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25
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Bale G, Mitra S, Tachtsidis I. Metabolic brain measurements in the newborn: Advances in optical technologies. Physiol Rep 2020; 8:e14548. [PMID: 32889790 PMCID: PMC7507543 DOI: 10.14814/phy2.14548] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 01/12/2023] Open
Abstract
Neonatal monitoring in neonatal intensive care is pushing the technological boundaries of newborn brain monitoring in order to improve patient outcome. There is an urgent need of a cot side, real time monitoring for assessment of brain injury severity and neurodevelopmental outcome, in particular for term newborn infants with hypoxic-ischemic brain injury. This topical review discusses why brain tissue metabolic monitoring is important in this group of infants and introduces the currently used neuromonitoring techniques for metabolic monitoring in the neonatal intensive care unit (NICU). New optical techniques that can monitor changes in brain metabolism together with brain hemodynamics at the cot side are presented. Early studies from these emerging technologies have demonstrated their potential to deliver continuous information regarding cerebral physiological changes in sick newborn infants in real time. The promises of these new tools as well as their potential limitations are discussed.
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Affiliation(s)
- Gemma Bale
- Medical Physics and Biomedical EngineeringUniversity College LondonLondonUK
| | - Subhabrata Mitra
- Neonatology, EGA Institute for Women's HealthUniversity College LondonLondonUK
| | - Ilias Tachtsidis
- Medical Physics and Biomedical EngineeringUniversity College LondonLondonUK
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26
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Fanjul-Vélez F, Pampín-Suárez S, Arce-Diego JL. Application of Classification Algorithms to Diffuse Reflectance Spectroscopy Measurements for Ex Vivo Characterization of Biological Tissues. ENTROPY 2020; 22:e22070736. [PMID: 33286511 PMCID: PMC7517275 DOI: 10.3390/e22070736] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 06/25/2020] [Accepted: 06/30/2020] [Indexed: 12/31/2022]
Abstract
Biological tissue identification in real clinical scenarios is a relevant and unsolved medical problem, particularly in the operating room. Although it could be thought that healthy tissue identification is an immediate task, in practice there are several clinical situations that greatly impede this process. For instance, it could be challenging in open surgery in complex areas, such as the neck, where different structures are quite close together, with bleeding and other artifacts affecting visual inspection. Solving this issue requires, on one hand, a high contrast noninvasive technique and, on the other hand, powerful classification algorithms. Regarding the technique, optical diffuse reflectance spectroscopy has demonstrated such capabilities in the discrimination of tumoral and healthy biological tissues. The complex signals obtained, in the form of spectra, need to be adequately computed in order to extract relevant information for discrimination. As usual, accurate discrimination relies on massive measurements, some of which serve as training sets for the classification algorithms. In this work, diffuse reflectance spectroscopy is proposed, implemented, and tested as a potential technique for healthy tissue discrimination. A specific setup is built and spectral measurements on several ex vivo porcine tissues are obtained. The massive data obtained are then analyzed for classification purposes. First of all, considerations about normalization, detrending and noise are taken into account. Dimensionality reduction and tendencies extraction are also considered. Featured spectral characteristics, principal component or linear discrimination analysis are applied, as long as classification approaches based on k-nearest neighbors (k-NN), quadratic discrimination analysis (QDA) or Naïve Bayes (NB). Relevant parameters about classification accuracy are obtained and compared, including ANOVA tests. The results show promising values of specificity and sensitivity of the technique for some classification algorithms, even over 95%, which could be relevant for clinical applications in the operating room.
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Mitra S, Bale G, Meek J, Tachtsidis I, Robertson NJ. Cerebral Near Infrared Spectroscopy Monitoring in Term Infants With Hypoxic Ischemic Encephalopathy-A Systematic Review. Front Neurol 2020; 11:393. [PMID: 32536901 PMCID: PMC7267214 DOI: 10.3389/fneur.2020.00393] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 04/17/2020] [Indexed: 12/13/2022] Open
Abstract
Background: Neonatal hypoxic ischemic encephalopathy (HIE) remains a significant cause of mortality and morbidity worldwide. Cerebral near infrared spectroscopy (NIRS) can provide cot side continuous information about changes in brain hemodynamics, oxygenation and metabolism in real time. Objective: To perform a systematic review of cerebral NIRS monitoring in term and near-term infants with HIE. Search Methods: A systematic search was performed in Ovid EMBASE and Medline database from inception to November 2019. The search combined three broad categories: measurement (NIRS monitoring), disease condition [hypoxic ischemic encephalopathy (HIE)] and subject category (newborn infants) using a stepwise approach as per PRISMA guidance. Selection Criteria: Only human studies published in English were included. Data Collection and Analysis: Two authors independently selected, assessed the quality, and extracted data from the studies for this review. Results: Forty-seven studies on term and near-term infants following HIE were identified. Most studies measured multi-distance NIRS based cerebral tissue saturation using monitors that are referred to as cerebral oximeters. Thirty-nine studies were published since 2010; eight studies were published before this. Fifteen studies reviewed the neurodevelopmental outcome in relation to NIRS findings. No randomized study was identified. Conclusion: Commercial NIRS cerebral oximeters can provide important information regarding changes in cerebral oxygenation and hemodynamics following HIE and can be particularly helpful when used in combination with other neuromonitoring tools. Optical measurements of brain metabolism using broadband NIRS and cerebral blood flow using diffuse correlation spectroscopy add additional pathophysiological information. Further randomized clinical trials and large observational studies are necessary with proper study design to assess the utility of NIRS in predicting neurodevelopmental outcome and guiding therapeutic interventions.
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Affiliation(s)
- Subhabrata Mitra
- Neonatology, Institute for Women's Health, University College London, London, United Kingdom
| | - Gemma Bale
- Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Judith Meek
- Neonatology, Institute for Women's Health, University College London, London, United Kingdom
| | - Ilias Tachtsidis
- Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Nicola J. Robertson
- Neonatology, Institute for Women's Health, University College London, London, United Kingdom
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Pruitt T, Wang X, Wu A, Kallioniemi E, Husain MM, Liu H. Transcranial Photobiomodulation (tPBM) With 1,064-nm Laser to Improve Cerebral Metabolism of the Human Brain In Vivo. Lasers Surg Med 2020; 52:807-813. [PMID: 32173886 PMCID: PMC7492377 DOI: 10.1002/lsm.23232] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/02/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND OBJECTIVES In our previous proof-of-principle study, transcranial photobiomodulation (tPBM) with 1,064-nm laser was reported to significantly increase concentration changes of oxygenated hemoglobin (∆[HbO]) and oxidized-state cytochrome c oxidase (∆[oxi-CCO]) in the human brain. This paper further investigated (i) its validity in two different subsets of young human subjects at two study sites over a period of 3 years and (ii) age-related effects of tPBM by comparing sham-controlled increases of ∆[HbO] and ∆[oxi-CCO] between young and older adults. STUDY DESIGN/MATERIALS AND METHODS We measured sham-controlled ∆[HbO] and ∆[oxi-CCO] using broadband near-infrared spectroscopy (bb-NIRS) in 15 young (26.7 ± 2.7 years of age) and 5 older (68.2 ± 4.8 years of age) healthy normal subjects before, during, and after right-forehead tPBM/sham stimulation with 1,064-nm laser. Student t tests were used to test statistical differences in tPBM-induced ∆[HbO] and ∆[oxi-CCO] (i) between the 15 young subjects and those of 11 reported previously and (ii) between the two age groups measured in this study. RESULTS Statistical analysis showed that no significant difference existed in ∆[HbO] and ∆[oxi-CCO] during and post tPBM between the two subsets of young subjects at two study sites over a period of 3 years. Furthermore, the two age groups showed statistically identical net increases in sham-controlled ∆[HbO] and ∆[oxi-CCO]. CONCLUSIONS This study provided strong evidence to validate/confirm our previous findings that tPBM with 1,064-nm laser enables to increase cerebral ∆[HbO] and ∆[oxi-CCO] in the human brain, as measured by bb-NIRS. Overall, it demonstrated the robust reproducibility of tPBM being able to improve cerebral hemodynamics and metabolism of the human brain in vivo in both young and older adults. Lasers Surg. Med. © 2020 The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals, Inc.
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Affiliation(s)
- Tyrell Pruitt
- Department of Bioengineering, University of Texas at Arlington, 500 UTA Blvd, Arlington, Texas, 76019.,Department of Psychiatry, UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, Texas, 75390
| | - Xinlong Wang
- Department of Bioengineering, University of Texas at Arlington, 500 UTA Blvd, Arlington, Texas, 76019
| | - Anqi Wu
- Department of Bioengineering, University of Texas at Arlington, 500 UTA Blvd, Arlington, Texas, 76019
| | - Elisa Kallioniemi
- Department of Psychiatry, UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, Texas, 75390
| | - Mustafa M Husain
- Department of Psychiatry, UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, Texas, 75390
| | - Hanli Liu
- Department of Bioengineering, University of Texas at Arlington, 500 UTA Blvd, Arlington, Texas, 76019
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Pinti P, Tachtsidis I, Hamilton A, Hirsch J, Aichelburg C, Gilbert S, Burgess PW. The present and future use of functional near-infrared spectroscopy (fNIRS) for cognitive neuroscience. Ann N Y Acad Sci 2020; 1464:5-29. [PMID: 30085354 PMCID: PMC6367070 DOI: 10.1111/nyas.13948] [Citation(s) in RCA: 433] [Impact Index Per Article: 108.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 07/10/2018] [Accepted: 07/13/2018] [Indexed: 01/11/2023]
Abstract
The past few decades have seen a rapid increase in the use of functional near-infrared spectroscopy (fNIRS) in cognitive neuroscience. This fast growth is due to the several advances that fNIRS offers over the other neuroimaging modalities such as functional magnetic resonance imaging and electroencephalography/magnetoencephalography. In particular, fNIRS is harmless, tolerant to bodily movements, and highly portable, being suitable for all possible participant populations, from newborns to the elderly and experimental settings, both inside and outside the laboratory. In this review we aim to provide a comprehensive and state-of-the-art review of fNIRS basics, technical developments, and applications. In particular, we discuss some of the open challenges and the potential of fNIRS for cognitive neuroscience research, with a particular focus on neuroimaging in naturalistic environments and social cognitive neuroscience.
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Affiliation(s)
- Paola Pinti
- Department of Medical Physics and Biomedical EngineeringUniversity College LondonLondonUK
- Institute of Cognitive NeuroscienceUniversity College LondonLondonUK
| | - Ilias Tachtsidis
- Department of Medical Physics and Biomedical EngineeringUniversity College LondonLondonUK
| | - Antonia Hamilton
- Institute of Cognitive NeuroscienceUniversity College LondonLondonUK
| | - Joy Hirsch
- Department of Medical Physics and Biomedical EngineeringUniversity College LondonLondonUK
- Department of PsychiatryYale School of MedicineNew HavenConnecticut
- Department of NeuroscienceYale School of MedicineNew HavenConnecticut
- Comparative MedicineYale School of MedicineNew HavenConnecticut
| | | | - Sam Gilbert
- Institute of Cognitive NeuroscienceUniversity College LondonLondonUK
| | - Paul W. Burgess
- Institute of Cognitive NeuroscienceUniversity College LondonLondonUK
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30
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Islam MN, Guo K, Zhai T, Memmini AK, Martinez R, Meah CN, Kovelman I, Weissman D, Hu X, Kim J, Broglio S, Beard D, VAN DEN Bergh F, Alam H, Russo R. Brain Metabolism Monitoring through CCO Measurements Using All-Fiber-Integrated Super-Continuum Source. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2020; 11234. [PMID: 34168393 DOI: 10.1117/12.2550137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
For monitoring of concussion, brain function, organ condition and other medical applications, what is needed is a non-invasive method of monitoring tissue metabolism. MRI-based functional imaging technology detects changes in blood oxygenation, a correlate of neural activity, and thus may offer a prediction of prognosis in cases of concussion and other cerebral traumas. Yet, potential relationships between perturbations to cerebral metabolism and patient outcomes cannot be effectively exploited clinically because we lack a practical, low-cost, non-invasive means to monitor cerebral oxygenation and metabolism in the emergency department, operating room, or medical facilities. We have developed a device to optically assay the redox state of Cytochrome-C-Oxidase (CCO), the mitochondrial enzyme responsible for the last step of the electron transport chain. Changes in CCO redox reflect changes in respiratory flux, and thus changes in the rate of oxidative adenosine triphosphate (ATP) synthesis. In other words, changes in CCO reflect brain cell's metabolic activity more directly than the traditional blood oxygenation measurement methods. To non-invasively measure changes in CCO as well as blood oxygenation, we have developed a Super-Continuum Infrared Spectroscopy of Cytochrome-C-Oxidase (SCISCCO) system that uses an all-fiber integrated, super-continuum light source to simultaneously measure both of the new (CCO) and the traditional (blood oxygenation) markers of neural metabolism. The SCISCCO system is validated by confirming the near-infrared spectrum of CCO in vitro. To demonstrate in vivo feasibility, the measured responses of oxygenation and CCO responses to acute ischemia (e.g., blood pressure tests) in human participants are compared to data from the literature. Furthermore, we show that the new device's measurements of oxygenated (HbO) and deoxygenated (HbR) hemoglobin in response to breath hold challenges are principled and consistent with previously reported findings. The validated SCISCCO system is finally applied to measure cerebral oxygenation and the redox state of CCO in participants during an attention test protocol. Twenty-five healthy adults completed an attention task that included nine 60-second periods of attention task, interleaved with 60-s periods of resting baseline. It has been well established that the frontal lobe of the human brain is active during tasks of attention. We therefore predicted that attention task should elicit an increase in HbO concentration accompanied by a decrease in redox state of CCO (e.g., ratio of oxidized CCO to reduced CCO) in frontal lobe brain regions as measured with the SCISCCO system. Our findings are consistent with our predictions: HbO concentration increases while CCO concentration decreases during the attention blocks relative to the resting baseline, thereby indicating an increase in oxidative metabolism of the frontal lobe brain regions of interest. Our systematic, multi-method approach thus validates the new device as well as the validity of the metabolic biomarkers that it measures. The SCISCCO system could be a new tool for monitoring brain and organ metabolism, which could be invaluable for screening concussion patients or use in an operating or emergency room to gauge patient's organ response to treatments.
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Affiliation(s)
- Mohammed N Islam
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA.,Omni Sciences Inc., 2125 Bishop Circle West Dexter MI 48130
| | - Kaiwen Guo
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Tianqu Zhai
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Allyssa K Memmini
- Michigan Concussion Center, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Ramon Martinez
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Cynthia N Meah
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Ioulia Kovelman
- Department of Psychology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Daniel Weissman
- Department of Psychology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Xiaosu Hu
- School of Dentistry, Department of Biologic and Materials Sciences & Prosthodontics, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Jessica Kim
- Department of Psychology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Steven Broglio
- Michigan Concussion Center, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Daniel Beard
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Francoise VAN DEN Bergh
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Hasan Alam
- Department of Surgery, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Rachel Russo
- Department of Surgery, University of Michigan, Ann Arbor, Michigan 48109, USA.,United States Air Force, Medical Corps, Travis, AFB 94533
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Broadband NIRS Cerebral Evaluation of the Hemodynamic and Oxidative State of Cytochrome-c-Oxidase Responses to +Gz Acceleration in Healthy Volunteers. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1232:339-345. [PMID: 31893429 PMCID: PMC7612835 DOI: 10.1007/978-3-030-34461-0_43] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We used a miniature broadband NIRS system to monitor concentration changes in brain oxygenation (oxy- and deoxy- haemoglobin [HbO2], [HHb]) and oxidised cytochrome-c-oxidase ([oxCCO]) during a high +Gz acceleration, induced by a human centrifuge, on two healthy experienced volunteers (2 male, 34 and 37 years). We performed a sequence of several +Gz exposures that were terminated at the onset of visual symptoms (loss of peripheral vision). Systemic parameters were recorded (i.e. heart rate, blood pressure and arterial saturation), and brain tissue blood volume changes ([HbT] = [HbO2] + [HHb]) and oxygen delivery ([HbDiff] = [HbO2] - [HHb]) were calculated. Volunteer 1 demonstrated a decrease in [HbT] of −3.49 ± 0.02 μMol and [HbDiff] of −3.23 ± 0.44 μMol, and an increase of [oxCCO] of 0.42 ± 0.01μMol. Volunteer 2 demonstrated a decrease in [HbDiff] of −4.37 ± 0.23 μMol, and no significant change in [HbT] (0.53 ± 0.06 μMol) and [oxCCO] (0.09 ± 0.06 μMol). The variability of the brain metabolic response was related to the level of ischaemia, suggesting that suppression of metabolism was due to lack of glucose substrate delivery rather than oxygen availability.
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Developing a Model to Simulate the Effect of Hypothermia on Cerebral Blood Flow and Metabolism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1232:299-306. [DOI: 10.1007/978-3-030-34461-0_38] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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33
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Changes in Brain Tissue Oxygenation and Metabolism During Rewarming After Neonatal Encephalopathy are Related to Electrical Abnormality. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1232:25-31. [PMID: 31893390 DOI: 10.1007/978-3-030-34461-0_4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Hypoxic ischemic encephalopathy (HIE) leads to significant mortality and morbidity, and therapeutic hypothermia (TH) has become a standard of care following HIE. After TH, the body temperature is brought back to 37 °C. Early electroencephalography (EEG) is a reliable outcome biomarker following HIE. We hypothesized that changes in cerebral oxidative metabolism, measured as Δ[oxCCO], in relation to changes in brain tissue oxygenation (measured as Δ[HbD]) during rewarming will correlate with injury severity as evidenced on amplitude integrated EEG/EEG at initial presentation. Broadband near-infrared spectroscopy (NIRS) and systemic data were collected during rewarming from 14 infants following HIE over a mean period of 12.5 h. All infants were monitored with video EEG telemetry using a standard neonatal montage. aEEG and EEG background was classified into mild, moderate and severely abnormal groups based on the background pattern. Two infants had mild, 6 infants had moderate and another 6 infants had severe abnormality at presentation. The relationship between [oxCCO] and [HbD] was evaluated between two groups of infants with abnormal electrical activity (mild vs moderate to severe). A significant difference was noted between the groups in the relationship between [oxCCO] and [HbD] (as r2) (p = 0.02). This result indicates that the mitochondrial injury and deranged oxidative metabolism persists in the moderate to severely abnormal group during rewarming.
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34
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Bale G, Taylor N, Mitra S, Sudakou A, de Roever I, Meek J, Robertson N, Tachtsidis I. Near-Infrared Spectroscopy Measured Cerebral Blood Flow from Spontaneous Oxygenation Changes in Neonatal Brain Injury. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1232:3-9. [PMID: 31893387 DOI: 10.1007/978-3-030-34461-0_1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
Neonates with hypoxic-ischaemic (HI) brain injury were monitored using a broadband near-infrared spectroscopy (NIRS) system in the neonatal intensive care unit. The aim of this work is to use the NIRS cerebral oxygenation data (HbD = oxygenated-haemoglobin - deoxygenated-haemoglobin) combined with arterial saturation (SaO2) from pulse oximetry to calculate cerebral blood flow (CBF) based on the oxygen swing method, during spontaneous desaturation episodes. The method is based on Fick's principle and uses HbD as a tracer; when a sudden change in SaO2 occurs, the change in HbD represents a change in tracer concentration, and thus it is possible to estimate CBF. CBF was successfully calculated with broadband NIRS in 11 HIE infants (3 with severe injury) for 70 oxygenation events on the day of birth. The average CBF was 18.0 ± 12.7 ml 100 g-1 min-1 with a range of 4 ml 100 g-1 min-1 to 60 ml 100 g-1 min-1. For infants with severe HIE (as determined by magnetic resonance spectroscopy) CBF was significantly lower (p = 0.038, d = 1.35) than those with moderate HIE on the day of birth.
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Affiliation(s)
- Gemma Bale
- Medical Physics and Biomedical Engineering, University College London, London, UK.
| | - Nathan Taylor
- Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Subhabrata Mitra
- Institute for Women's Health, University College London, London, UK
| | - Aleh Sudakou
- Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Warsaw, Poland
| | - Isabel de Roever
- Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Judith Meek
- Institute for Women's Health, University College London, London, UK
| | - Nicola Robertson
- Institute for Women's Health, University College London, London, UK
| | - Ilias Tachtsidis
- Medical Physics and Biomedical Engineering, University College London, London, UK
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Broadband Time Domain Diffuse Optical Reflectance Spectroscopy: A Review of Systems, Methods, and Applications. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9245465] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This review presents recent developments and a wide overview of broadband time domain diffuse optical spectroscopy (TD-DOS). Various topics including physics of photon migration, advanced instrumentation, methods of analysis, applications covering multiple domains (tissue chromophore, in vivo studies, food, wood, pharmaceutical industry) are elaborated. The key role of standardization and recent studies in that direction are discussed. Towards the end, a brief outlook is presented on the current status and future trends in broadband TD-DOS.
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Kaynezhad P, Mitra S, Bale G, Bauer C, Lingam I, Meehan C, Avdic-Belltheus A, Martinello KA, Bainbridge A, Robertson NJ, Tachtsidis I. Quantification of the severity of hypoxic-ischemic brain injury in a neonatal preclinical model using measurements of cytochrome-c-oxidase from a miniature broadband-near-infrared spectroscopy system. NEUROPHOTONICS 2019; 6:045009. [PMID: 31737744 PMCID: PMC6855218 DOI: 10.1117/1.nph.6.4.045009] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 10/14/2019] [Indexed: 05/05/2023]
Abstract
We describe the development of a miniaturized broadband near-infrared spectroscopy system (bNIRS), which measures changes in cerebral tissue oxyhemoglobin ( [ HbO 2 ] ) and deoxyhemoglobin ([HHb]) plus tissue metabolism via changes in the oxidation state of cytochrome-c-oxidase ([oxCCO]). The system is based on a small light source and a customized mini-spectrometer. We assessed the instrument in a preclinical study in 27 newborn piglets undergoing transient cerebral hypoxia-ischemia (HI). We aimed to quantify the recovery of the HI insult and estimate the severity of the injury. The recovery in brain oxygenation ( Δ [ HbDiff ] = Δ [ HbO 2 ] - Δ [ HHb ] ), blood volume ( Δ [ HbT ] = Δ [ HbO 2 ] + Δ [ HHb ] ), and metabolism ( Δ [ oxCCO ] ) for up to 30 min after the end of HI were quantified in percentages using the recovery fraction (RF) algorithm, which quantifies the recovery of a signal with respect to baseline. The receiver operating characteristic analysis was performed on bNIRS-RF measurements compared to proton ( H 1 ) magnetic resonance spectroscopic (MRS)-derived thalamic lactate/N-acetylaspartate (Lac/NAA) measured at 24-h post HI insult; Lac/NAA peak area ratio is an accurate surrogate marker of neurodevelopmental outcome in babies with neonatal HI encephalopathy. The Δ [ oxCCO ] -RF cut-off threshold of 79% within 30 min of HI predicted injury severity based on Lac/NAA with high sensitivity (100%) and specificity (93%). A significant difference in thalamic Lac/NAA was noticed ( p < 0.0001 ) between the two groups based on this cut-off threshold of 79% Δ [ oxCCO ] -RF. The severe injury group ( n = 13 ) had ∼ 30 % smaller recovery in Δ [ HbDiff ] -RF ( p = 0.0001 ) and no significant difference was observed in Δ [ HbT ] -RF between groups. At 48 h post HI, significantly higher P 31 -MRS-measured inorganic phosphate/exchangeable phosphate pool (epp) ( p = 0.01 ) and reduced phosphocreatine/epp ( p = 0.003 ) were observed in the severe injury group indicating persistent cerebral energy depletion. Based on these results, the bNIRS measurement of the oxCCO recovery fraction offers a noninvasive real-time biomarker of brain injury severity within 30 min following HI insult.
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Affiliation(s)
- Pardis Kaynezhad
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
- Address all correspondence to Ilias Tachtsidis, E-mail:
| | - Subhabrata Mitra
- University College London, Institute for Women’s Health, London, United Kingdom
| | - Gemma Bale
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Cornelius Bauer
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Ingran Lingam
- University College London, Institute for Women’s Health, London, United Kingdom
| | - Christopher Meehan
- University College London, Institute for Women’s Health, London, United Kingdom
| | | | | | - Alan Bainbridge
- University College London Hospital, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Nicola J. Robertson
- University College London, Institute for Women’s Health, London, United Kingdom
| | - Ilias Tachtsidis
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
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Bale G, Mitra S, de Roever I, Sokolska M, Price D, Bainbridge A, Gunny R, Uria-Avellanal C, Kendall GS, Meek J, Robertson NJ, Tachtsidis I. Oxygen dependency of mitochondrial metabolism indicates outcome of newborn brain injury. J Cereb Blood Flow Metab 2019; 39:2035-2047. [PMID: 29775114 PMCID: PMC6775592 DOI: 10.1177/0271678x18777928] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
There is a need for a method of real-time assessment of brain metabolism during neonatal hypoxic-ischaemic encephalopathy (HIE). We have used broadband near-infrared spectroscopy (NIRS) to monitor cerebral oxygenation and metabolic changes in 50 neonates with HIE undergoing therapeutic hypothermia treatment. In 24 neonates, 54 episodes of spontaneous decreases in peripheral oxygen saturation (desaturations) were recorded between 6 and 81 h after birth. We observed differences in the cerebral metabolic responses to these episodes that were related to the predicted outcome of the injury, as determined by subsequent magnetic resonance spectroscopy derived lactate/N-acetyl-aspartate. We demonstrated that a strong relationship between cerebral metabolism (broadband NIRS-measured cytochrome-c-oxidase (CCO)) and cerebral oxygenation was associated with unfavourable outcome; this is likely to be due to a lower cerebral metabolic rate and mitochondrial dysfunction in severe encephalopathy. Specifically, a decrease in the brain tissue oxidation state of CCO greater than 0.06 µM per 1 µM brain haemoglobin oxygenation drop was able to predict the outcome with 64% sensitivity and 79% specificity (receiver operating characteristic area under the curve = 0.73). With further work on the implementation of this methodology, broadband NIRS has the potential to provide an early, cotside, non-invasive, clinically relevant metabolic marker of perinatal hypoxic-ischaemic injury.
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Affiliation(s)
- Gemma Bale
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Subhabrata Mitra
- Institute of Women's Health, University College London, London, UK
| | - Isabel de Roever
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Magdalena Sokolska
- Department of Medical Physics and Biomedical Engineering, University College London Hospital, London, UK
| | - David Price
- Department of Medical Physics and Biomedical Engineering, University College London Hospital, London, UK
| | - Alan Bainbridge
- Department of Medical Physics and Biomedical Engineering, University College London Hospital, London, UK
| | - Roxana Gunny
- Paediatric Neuroradiology, Great Ormond Street Hospital for Children, London, UK
| | | | - Giles S Kendall
- Neonatal Unit, University College London Hospital, London, UK
| | - Judith Meek
- Institute of Women's Health, University College London, London, UK
| | | | - Ilias Tachtsidis
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
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Sudakou A, Wojtkiewicz S, Lange F, Gerega A, Sawosz P, Tachtsidis I, Liebert A. Depth-resolved assessment of changes in concentration of chromophores using time-resolved near-infrared spectroscopy: estimation of cytochrome-c-oxidase uncertainty by Monte Carlo simulations. BIOMEDICAL OPTICS EXPRESS 2019; 10:4621-4635. [PMID: 31565513 PMCID: PMC6757481 DOI: 10.1364/boe.10.004621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 08/05/2019] [Accepted: 08/06/2019] [Indexed: 06/10/2023]
Abstract
Time-resolved near-infrared spectroscopy (TR-NIRS) measurements can be used to recover changes in concentrations of tissue constituents ( Δ C ) by applying the moments method and the Beer-Lambert law. In this work we carried out the error propagation analysis allowing to calculate the standard deviations of uncertainty in estimation of the Δ C . Here, we show the process of choosing wavelengths for the evaluation of hemodynamic (oxy-, deoxyhemoglobin) and metabolic (cytochrome-c-oxidase (CCO)) responses within the brain tissue as measured with an in-house developed TR-NIRS multi-wavelength system, which measures at 16 consecutive wavelengths separated by 12.5 nm and placed between 650 and 950 nm. Data generated with Monte Carlo simulations on three-layered model (scalp, skull, brain) for wavelengths range from 650 to 950 nm were used to carry out the error propagation analysis for varying choices of wavelengths. For a detector with a spectrally uniform responsivity, the minimal standard deviation of the estimated changes in CCO within the brain layer, σ Δ C CCO brain = 0.40 µM, was observed for the 16 consecutive wavelengths from 725 to 912.5 nm. For realistic a detector model, i.e. the spectral responsivity characteristic is considered, the minimum, σ Δ C CCO brain = 0.47 µM, was observed at the 16 consecutive wavelengths from 688 to 875 nm. We introduce the method of applying the error propagation analysis to data as measured with spectral TR-NIRS systems to calculate uncertainty of recovery of tissue constituents concentrations.
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Affiliation(s)
- Aleh Sudakou
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Trojdena 4, 02-109 Warsaw, Poland
| | - Stanislaw Wojtkiewicz
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Trojdena 4, 02-109 Warsaw, Poland
- School of Computer Science, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Frédéric Lange
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, United Kingdom
| | - Anna Gerega
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Trojdena 4, 02-109 Warsaw, Poland
| | - Piotr Sawosz
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Trojdena 4, 02-109 Warsaw, Poland
| | - Ilias Tachtsidis
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, United Kingdom
| | - Adam Liebert
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Trojdena 4, 02-109 Warsaw, Poland
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Holper L, Lan MJ, Brown PJ, Sublette ME, Burke A, Mann JJ. Brain cytochrome-c-oxidase as a marker of mitochondrial function: A pilot study in major depression using NIRS. Depress Anxiety 2019; 36:766-779. [PMID: 31111623 PMCID: PMC6716511 DOI: 10.1002/da.22913] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 03/12/2019] [Accepted: 04/22/2019] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Brain mitochondrial dysfunction is implicated in the pathophysiology of mood disorders. Brain cytochrome-c-oxidase (COX) activity is associated with the mitochondrial function. Near-infrared spectroscopy (NIRS) noninvasively measures oxidized COX (oxCOX) and tissue oxygenation index (TOI) reflecting cerebral blood flow and oxygenation. METHODS oxCOX and TOI were assessed in prefrontal cortex (Fp1/2, Brodmann area 10) in patients in a major depressive episode (N = 13) with major depressive disorder (MDD; N = 7) and bipolar disorder (BD; N = 6) compared with the controls (N = 10). One patient with MDD and all the patients with BD were taking medications. Computational modeling estimated oxCOX and TOI related indices of mitochondrial function and cerebral blood flow, respectively. RESULTS oxCOX was lower in patients than controls (p = .014) correlating inversely with depression severity (r = -.72; p = .006), driven primarily by lower oxCOX in BD compared with the controls. Computationally modeled mitochondrial parameters of the electron transport chain, such as the nicotinamide adenine dinucleotide ratio (NAD+ /NADH; p = .001) and the proton leak rate across the inner mitochondrial membrane (klk2 ; p = .008), were also lower in patients and correlated inversely with depression severity. No such effects were found for TOI. CONCLUSIONS In this pilot study, oxCOX and related mitochondrial parameters assessed by NIRS indicate an abnormal cerebral metabolic state in mood disorders proportional to depression severity, potentially providing a biomarker of antidepressant effect. Because the effect was driven by the medicated BD group, findings need to be evaluated in a larger, medication-free population.
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Affiliation(s)
- L Holper
- Division of Molecular Imaging and Neuropathology, Columbia University and New York State Psychiatric Institute, New York, NY,Department of Psychiatry, Psychotherapy, and Psychosomatics, University Hospital of Psychiatry Zurich, 8032 Zurich, Switzerland
| | - MJ Lan
- Division of Molecular Imaging and Neuropathology, Columbia University and New York State Psychiatric Institute, New York, NY
| | - PJ Brown
- Geriatric Psychiatry, Columbia University College of Physicians and Surgeons and New York State Psychiatric Institute, New York, NY
| | - ME Sublette
- Division of Molecular Imaging and Neuropathology, Columbia University and New York State Psychiatric Institute, New York, NY
| | - A Burke
- Division of Molecular Imaging and Neuropathology, Columbia University and New York State Psychiatric Institute, New York, NY
| | - JJ Mann
- Division of Molecular Imaging and Neuropathology, Columbia University and New York State Psychiatric Institute, New York, NY,Department of Radiology, Columbia University, New York, NY
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Changes in Cytochrome-C-Oxidase Account for Changes in Attenuation of Near-Infrared Light in the Healthy Infant Brain. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1072:7-12. [PMID: 30178316 PMCID: PMC6821534 DOI: 10.1007/978-3-319-91287-5_2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
A novel multi-wavelength broadband near infrared spectroscopy (NIRS) system has been employed to simultaneously measure haemodynamic changes alongside changes in cellular oxygen utilization by measurement of oxidation state of mitochondrial enzyme cytochrome-c-oxidase (oxCCO). The aim of this study was to investigate the role of oxCCO in neural responses to functional activation in infants. Studies were performed using a NIRS broadband system in 33 typically developing infants aged between 4 and 6 months. Responses were recorded over the right temporal lobe while infants were presented with engaging videos containing social and non-social content. Changes in the concentration of oxyhaemoglobin (Δ[HbO2]), deoxyhaemoglobin (Δ[HHb]) and Δ[oxCCO] were calculated using changes in attenuation of light at 120 wavelengths between 780 and 900 nm using the UCLn algorithm. The algorithm was also used to fit (a) HbO2 and HHb spectra (2 component fit) and (b) HbO2, HHb and oxCCO (3 component fit) to the change in attenuation occurring within an experimental block in different participants. Residuals resulting from these two fits were compared with oxidized-minus reduced CCO spectrum, calculated using the CCO specific extinction coefficient. A significant increase in oxCCO was found in response to the social stimuli (maximum increase 0.238 ± 0.13 μM). Residuals analysis showed that the best fits were achieved when oxCCO was included as a tissue chromophore. These results are the first reported significant change in oxCCO to stimulus-evoked activation in infants and may reveal vital information about oxygen metabolism during functional activation in the developing human brain.
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Russell-Buckland J, Bale G, de Roever I, Tachtsidis I. ABroAD: A Machine Learning Based Approach to Detect Broadband NIRS Artefacts. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1072:319-324. [PMID: 30178365 PMCID: PMC6142856 DOI: 10.1007/978-3-319-91287-5_51] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/29/2022]
Abstract
Artefacts are a common and unwanted aspect of any measurement process, especially in a clinical environment, with multiple causes such as environmental changes or motion. In near-infrared spectroscopy (NIRS), there are several existing methods that can be used to identify and remove artefacts to improve the quality of collected data.We have developed a novel Automatic Broadband Artefact Detection (ABroAD) process, using machine learning methods alongside broadband NIRS data to detect common measurement artefacts using the broadband intensity spectrum. Data were collected from eight subjects, using a broadband NIRS monitoring over the frontal lobe with two sensors. Six different artificial artefacts - vertical head movement, horizontal head movement, frowning, pressure, ambient light, torch light - were simulated using movement and light changes on eight subjects in a block test design. It was possible to identify both light artefacts to a good degree, as well as pressure artefacts. This is promising and, by expanding this work to larger datasets, it may be possible to create and train a machine learning pipeline to automate the detection of various artefacts, making the analysis of collected data more reliable.
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Affiliation(s)
| | - Gemma Bale
- Biomedical Optics Research Laboratory, University College London, London, UK
| | - Isabel de Roever
- Biomedical Optics Research Laboratory, University College London, London, UK
| | - Ilias Tachtsidis
- Biomedical Optics Research Laboratory, University College London, London, UK
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Lange F, Dunne L, Hale L, Tachtsidis I. MAESTROS: A Multiwavelength Time-Domain NIRS System to Monitor Changes in Oxygenation and Oxidation State of Cytochrome-C-Oxidase. IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS : A PUBLICATION OF THE IEEE LASERS AND ELECTRO-OPTICS SOCIETY 2019; 25:7100312. [PMID: 30450021 PMCID: PMC6054019 DOI: 10.1109/jstqe.2018.2833205] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/30/2018] [Accepted: 04/30/2018] [Indexed: 05/17/2023]
Abstract
We present a multiwavelength, multichannel, time-domain near-infrared spectroscopy system named MAESTROS. This instrument can measure absorption and scattering coefficients and can quantify the concentrations of oxy- and deoxy-haemoglobin ([HbO2], [HHb]), and oxidation state of cytochrome-c-oxidase ([oxCCO]). This system is composed of a supercontinuum laser source coupled with two acousto-optic tuneable filters. The light is collected by four photomultipliers tubes, connected to a router to redirect the signal to a single time-correlated single-photon counting card. The interface between the system and the tissue is based on optical fibres. This arrangement allows us to resolve up to 16 wavelengths, within the range of 650-900 nm, at a sampling rate compatible with the physiology (from 0.5 to 2 Hz). In this paper, we describe the system and assess its performance based on two specifically designed protocols for photon migration instruments, the basic instrument protocol and nEUROPt protocols, and on a well characterized liquid phantom based on Intralipid and water. Then, the ability to resolve [HbO2 ], [HHb], and [oxCCO] is demonstrated on a homogeneous liquid phantom, based on blood for [HbO2], [HHb], and yeast for [oxCCO]. In the future, the system could be used to monitor brain tissue physiology.
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Affiliation(s)
- Frederic Lange
- 1Biomedical Optics Research Laboratory Department of Medical Physics and Biomedical Engineering University College London LondonWC1E 6BTU.K
| | - Luke Dunne
- 1Biomedical Optics Research Laboratory Department of Medical Physics and Biomedical Engineering University College London LondonWC1E 6BTU.K
| | - Lucy Hale
- 2Biomedical Optics Research Laboratory Department of Medical Physics and Biomedical Engineering University College London LondonWC1E 6BTU.K
- 3Electronic and Electrical Engineering University College London LondonWC1E 7JEU.K
| | - Ilias Tachtsidis
- 1Biomedical Optics Research Laboratory Department of Medical Physics and Biomedical Engineering University College London LondonWC1E 6BTU.K
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Mitra S, Bale G, Highton D, Gunny R, Uria-Avellanal C, Bainbridge A, Sokolska M, Price D, Huertas-Ceballos A, Kendall GS, Meek J, Tachtsidis I, Robertson NJ. Pressure passivity of cerebral mitochondrial metabolism is associated with poor outcome following perinatal hypoxic ischemic brain injury. J Cereb Blood Flow Metab 2019; 39:118-130. [PMID: 28949271 PMCID: PMC6311664 DOI: 10.1177/0271678x17733639] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hypoxic ischemic encephalopathy (HIE) leads to significant morbidity and mortality. Impaired autoregulation after hypoxia-ischaemia has been suggested to contribute further to injury. Thalamic lactate/N-Acetylasperate (Lac/NAA) peak area ratio of > 0.3 on proton (1H) magnetic resonance spectroscopy (MRS) is associated with poor neurodevelopment outcome following HIE. Cytochrome-c-oxidase (CCO) plays a central role in mitochondrial oxidative metabolism and ATP synthesis. Using a novel broadband NIRS system, we investigated the impact of pressure passivity of cerebral metabolism (CCO), oxygenation (haemoglobin difference (HbD)) and cerebral blood volume (total haemoglobin (HbT)) in 23 term infants following HIE during therapeutic hypothermia (HT). Sixty-minute epochs of data from each infant were studied using wavelet analysis at a mean age of 48 h. Wavelet semblance (a measure of phase difference) was calculated to compare reactivity between mean arterial blood pressure (MABP) with oxCCO, HbD and HbT. OxCCO-MABP semblance correlated with thalamic Lac/NAA ( r = 0.48, p = 0.02). OxCCO-MABP semblance also differed between groups of infants with mild to moderate and severe injury measured using brain MRI score ( p = 0.04), thalamic Lac/NAA ( p = 0.04) and neurodevelopmental outcome at one year ( p = 0.04). Pressure passive changes in cerebral metabolism were associated with injury severity indicated by thalamic Lac/NAA, MRI scores and neurodevelopmental assessment at one year of age.
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Affiliation(s)
- Subhabrata Mitra
- 1 Institute for Women's Health, University College London, London, UK
| | - Gemma Bale
- 2 Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - David Highton
- 3 Neurocritical Care, National Hospital for Neurology & Neurosurgery, University College London, London, UK
| | - Roxanna Gunny
- 4 Paediatric Neuroradiology, Great Ormond Street Hospital for Children, London, UK
| | | | - Alan Bainbridge
- 5 Department of Medical Physics and Biomedical Engineering, University College London Hospital, London, UK
| | - Magdalena Sokolska
- 5 Department of Medical Physics and Biomedical Engineering, University College London Hospital, London, UK
| | - David Price
- 5 Department of Medical Physics and Biomedical Engineering, University College London Hospital, London, UK
| | | | - Giles S Kendall
- 6 Neonatal Unit, University College London Hospital, London, UK
| | - Judith Meek
- 1 Institute for Women's Health, University College London, London, UK
| | - Ilias Tachtsidis
- 2 Department of Medical Physics and Biomedical Engineering, University College London, London, UK
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de Roever I, Bale G, Mitra S, Meek J, Robertson NJ, Tachtsidis I. Investigation of the Pattern of the Hemodynamic Response as Measured by Functional Near-Infrared Spectroscopy (fNIRS) Studies in Newborns, Less Than a Month Old: A Systematic Review. Front Hum Neurosci 2018; 12:371. [PMID: 30333736 PMCID: PMC6176492 DOI: 10.3389/fnhum.2018.00371] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Accepted: 08/29/2018] [Indexed: 01/03/2023] Open
Abstract
It has been 20 years since functional near-infrared spectroscopy (fNIRS) was first used to investigate the evoked hemodynamic response to a stimulus in newborns. The hemodynamic response to functional activation is well-established in adults, with an observed increase in concentration change of oxygenated hemoglobin (Δ[HbO2]) and decrease in deoxygenated hemoglobin (Δ[HHb]). However, functional studies in newborns have revealed a mixed response, particularly with Δ[HHb] where an inconsistent change in direction is observed. The reason for this heterogeneity is unknown, with potential explanations arising from differing physiology in the developing brain, or differences in instrumentation or methodology. The aim of this review is to collate the findings from studies that have employed fNIRS to monitor cerebral hemodynamics in term newborn infants aged 1 day-1 month. A total of 46 eligible studies were identified; some studies investigated more than one stimulus type, resulting in a total of 51 reported results. The NIRS parameters reported varied across studies with 50/51 cases reporting Δ[HbO2], 39/51 reporting Δ[HHb], and 13/51 reporting total hemoglobin concentration Δ[HbT] (Δ[HbO2] + Δ[HHb]). However, of the 39 cases reporting Δ[HHb] in graphs or tables, only 24 studies explicitly discussed the response (i.e., direction of change) of this variable. In the studies where the fNIRS responses were discussed, 46/51 cases observed an increase in Δ[HbO2], 7/51 observed an increase or varied Δ[HHb], and 2/51 reported a varied or negative Δ[HbT]. An increase in Δ[HbO2] and decrease or no change in Δ[HHb] was observed in 15 studies. By reviewing this body of literature, we have identified that the majority of research articles reported an increase in Δ[HbO2] across various functional tasks and did not report the response of Δ[HHb]. Confirming the normal, healthy hemodynamic response in newborns will allow identification of unhealthy patterns and their association to normal neurodevelopment.
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Affiliation(s)
- Isabel de Roever
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Gemma Bale
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Subhabrata Mitra
- Department of Neonatology, Institute for Women's Health, University College London, London, United Kingdom
| | - Judith Meek
- Department of Neonatology, Institute for Women's Health, University College London, London, United Kingdom
| | - Nicola J. Robertson
- Department of Neonatology, Institute for Women's Health, University College London, London, United Kingdom
| | - Ilias Tachtsidis
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
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45
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Holper L, Mann JJ. Test-retest reliability of brain mitochondrial cytochrome-c-oxidase assessed by functional near-infrared spectroscopy. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-9. [PMID: 29766685 DOI: 10.1117/1.jbo.23.5.056006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 04/24/2018] [Indexed: 05/10/2023]
Abstract
Functional near-infrared spectroscopy (fNIRS) is a noninvasive method for measuring in vivo both hemodynamic and mitochondrial metabolic activities in brain cortical structures. Although the test-retest reliability of the hemodynamic measures, such as reflected by oxygenated (HbO2), deoxygenated (HHb) hemoglobin, and the tissue oxygenation index (TOI), has been previously reported to be good to excellent, the reliability of the metabolic signal indexed by oxidized cytochrome-c-oxidase (oxCCO) has not been reported. The present test-retest study compared the reliability of the metabolic and hemodynamic signals in 10 healthy participants undergoing hypo- and hypercapnia challenges. The primary reliability measure was the intraclass correlation coefficient (ICC). Results of both hypo- and hypercapnia showed that the oxCCO signal (ICC = 0.876 / 0.757) had robust reliability comparable with that of the HbO2 (ICC = 0.841 / 0.801), HHb (ICC = 0.804 / 0.571), and TOI (ICC = 0.574 / 0.614) signals. These findings show that the oxCCO signal can be assessed by fNIRS with comparable reliability to the hemodynamic measures. We discuss the results in light of current interest in a mitochondrial metabolic marker derived from fNIRS.
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Affiliation(s)
- Lisa Holper
- Columbia University, New York State Psychiatric Institute, Division of Molecular Imaging and Neuropa, United States
| | - J John Mann
- Columbia University, New York State Psychiatric Institute, Division of Molecular Imaging and Neuropa, United States
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Fanjul-Vélez F, Arévalo-Díaz L, Arce-Diego JL. Intra-class variability in diffuse reflectance spectroscopy: application to porcine adipose tissue. BIOMEDICAL OPTICS EXPRESS 2018; 9:2297-2303. [PMID: 29760988 PMCID: PMC5946789 DOI: 10.1364/boe.9.002297] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/05/2018] [Accepted: 04/09/2018] [Indexed: 05/06/2023]
Abstract
Optical diffuse reflectance spectroscopy (DRS) has great potential in the study, diagnosis, and discrimination of biological tissues. Discrimination is based on massive measurements that conform training sets. These sets are then used to classify tissues according to the biomedical application. Classification accuracy depends strongly on the training dataset, which typically comes from different samples of the same class, and from different points of the same sample. The variability of these measurements is not usually considered and is assumed to be purely random, although it could greatly influence the results. In this work, spectral variations within and between samples of different animals of ex-vivo porcine adipose tissue are evaluated. Algorithms for normalization, dimensionality reduction by principal component analysis, and variability control are applied. The PC analysis shows the dataset variability, even when a variability removal algorithm is applied. The projected data appear grouped by animal in the PC space. Mahalanobis distance is calculated for every group, and an ANOVA test is performed in order to estimate the variability. The results confirm that the variability is not random and is dependent at least on the anatomical location and the specific animal. The variability magnitude is significant, particularly if the classification accuracy is needed to be high. As a consequence, it should be taken generally into account in classification problems.
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47
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Beausoleil TP, Janaillac M, Barrington KJ, Lapointe A, Dehaes M. Cerebral oxygen saturation and peripheral perfusion in the extremely premature infant with intraventricular and/or pulmonary haemorrhage early in life. Sci Rep 2018; 8:6511. [PMID: 29695729 PMCID: PMC5916916 DOI: 10.1038/s41598-018-24836-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 04/09/2018] [Indexed: 12/29/2022] Open
Abstract
Extremely preterm infants are at higher risk of pulmonary (PH) and intraventricular (IVH) haemorrhage during the transitioning physiology due to immature cardiovascular system. Monitoring of haemodynamics can detect early abnormal circulation that may lead to these complications. We described time-frequency relationships between near infrared spectroscopy (NIRS) cerebral regional haemoglobin oxygen saturation (CrSO2) and preductal peripheral perfusion index (PI), capillary oxygen saturation (SpO2) and heart rate (HR) in extremely preterm infants in the first 72 h of life. Patients were sub-grouped in infants with PH and/or IVH (N H = 8) and healthy controls (N C = 11). Data were decomposed in wavelets allowing the analysis of localized variations of power. This approach allowed to quantify the percentage of time of significant cross-correlation, semblance, gain (transfer function) and coherence between signals. Ultra-low frequencies (<0.28 mHz) were analyzed as slow and prolonged periods of impaired circulation are considered more detrimental than transient fluctuations. Cross-correlation between CrSO2 and oximetry (PI, SpO2 and HR) as well as in-phase semblance and gain between CrSO2 and HR were significantly lower while anti-phase semblance between CrSO2 and HR was significantly higher in PH-IVH infants compared to controls. These differences may reflect haemodynamic instability associated with cerebrovascular autoregulation and hemorrhagic complications observed during the transitioning physiology.
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Affiliation(s)
- Thierry P Beausoleil
- Institute of Biomedical Engineering, University of Montréal, Montréal, Canada.,Research Centre, CHU Sainte-Justine, Montréal, Canada
| | - Marie Janaillac
- Department of Pediatrics, Division of Neonatology, CHU Sainte-Justine and University of Montréal, Montréal, Canada
| | - Keith J Barrington
- Research Centre, CHU Sainte-Justine, Montréal, Canada.,Department of Pediatrics, Division of Neonatology, CHU Sainte-Justine and University of Montréal, Montréal, Canada
| | - Anie Lapointe
- Department of Pediatrics, Division of Neonatology, CHU Sainte-Justine and University of Montréal, Montréal, Canada
| | - Mathieu Dehaes
- Research Centre, CHU Sainte-Justine, Montréal, Canada. .,Department of Radiology, Radio-oncology and Nuclear Medicine, University of Montréal, Montréal, Canada.
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Investigation of Confounding Factors in Measuring Tissue Saturation with NIRS Spatially Resolved Spectroscopy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1072:307-312. [PMID: 30178363 PMCID: PMC6142855 DOI: 10.1007/978-3-319-91287-5_49] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Performing absolute measurements of tissue saturation of the brain with near-infrared spectroscopy (NIRS) is a clinically desirable brain monitoring tool. Tissue oxygenation index (TOI) is an indicator of absolute tissue mixed arterial and venous oxygen saturation, and can be calculated using a NIRS technique called spatially resolved spectroscopy (SRS). SRS instruments measure the change of light attenuation with distance by using multiple light source-detector distances at two or more wavelengths. The aim of the study is to use broadband NIRS SRS data to investigate the effects on the calculation of TOI of different parameters: wavelength selection, scattering dependence, source-detector distance, and resolving for water. In total, 55 neonates with hypoxic-ischemic encephalopathy were monitored using a broadband multi-distance continuous wave NIRS system; 172 datasets were recorded. Using a "Standard" approach, TOI values between 0 and 100% ("good") were calculated in 157/172 datasets with a mean TOI of 50%. By changing the wavelength selection, the number of "good" data sets increases to 165/172 with a mean of 60%. Alteration of the dependence of scattering on wavelength acts as a constant which shifts the absolute value of TOI significantly (p < 0.05), demonstrating the importance of having a subject-appropriate estimation of scattering dependence. In general, changing the combination of source-detector distances does not significantly alter the TOI (the mean TOI ranges from 41% to 53%) which suggests that the algorithm is robust to different source-detector combinations. The study shows the broadband NIRS SRS algorithm gives the opportunity to explore the calculation of TOI and could further improve the measurement of tissue saturation in a clinical setting.
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Correlations between near-infrared spectroscopy, perfusion index, and cardiac outputs in extremely preterm infants in the first 72 h of life. Eur J Pediatr 2018; 177:541-550. [PMID: 29374830 DOI: 10.1007/s00431-018-3096-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 12/14/2017] [Accepted: 01/17/2018] [Indexed: 10/18/2022]
Abstract
UNLABELLED Haemodynamic assessment during the transitional period in preterm infants is challenging. We aimed to describe the relationships between cerebral regional tissue oxygen saturation (CrSO2), perfusion index (PI), echocardiographic, and clinical parameters in extremely preterm infants in their first 72 h of life. Twenty newborns born at < 28 weeks of gestation were continuously monitored with CrSO2 and preductal PI. Cardiac output was measured at H6, H24, H48, and H72. The median gestational age and birth weight were 25.0 weeks (24-26) and 750 g (655-920), respectively. CrSO2 and preductal PI had r values < 0.35 with blood gases, lactates, haemoglobin, and mean blood pressure. Cardiac output significantly increased over the 72 h of the study period. Fifteen patients had at least one episode of low left and/or right ventricular output (RVO), during which there was a strong correlation between CrSO2 and superior vena cava (SVC) flow (at H6 (r = 0.74) and H24 (r = 0.86)) and between PI and RVO (at H6 (r = 0.68) and H24 (r = 0.92)). Five patients had low SVC flow (≤ 40 mL/kg/min) at H6, during which PI was strongly correlated with RVO (r = 0.98). CONCLUSION CrSO2 and preductal PI are strongly correlated with cardiac output during low cardiac output states. What is Known: • Perfusion index and near-infrared spectroscopy are non-invasive tools to evaluate haemodynamics in preterm infants. • Pre- and postductal perfusion indexes strongly correlate with left ventricular output in term infants, and near-infrared spectroscopy has been validated to assess cerebral oxygenation in term and preterm infants. What is New: • Cerebral regional tissue oxygen saturation and preductal perfusion index were strongly correlated with cardiac output during low cardiac output states. • The strength of the correlation between cerebral regional tissue oxygen saturation, preductal perfusion index, and cardiac output varied in the first 72 h of life, reflecting the complexity of the transitional physiology.
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Wang X, Tian F, Reddy DD, Nalawade SS, Barrett DW, Gonzalez-Lima F, Liu H. Up-regulation of cerebral cytochrome-c-oxidase and hemodynamics by transcranial infrared laser stimulation: A broadband near-infrared spectroscopy study. J Cereb Blood Flow Metab 2017; 37:3789-3802. [PMID: 28178891 PMCID: PMC5718323 DOI: 10.1177/0271678x17691783] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Transcranial infrared laser stimulation (TILS) is a noninvasive form of brain photobiomulation. Cytochrome-c-oxidase (CCO), the terminal enzyme in the mitochondrial electron transport chain, is hypothesized to be the primary intracellular photoacceptor. We hypothesized that TILS up-regulates cerebral CCO and causes hemodynamic changes. We delivered 1064-nm laser stimulation to the forehead of healthy participants ( n = 11), while broadband near-infrared spectroscopy was utilized to acquire light reflectance from the TILS-treated cortical region before, during, and after TILS. Placebo experiments were also performed for accurate comparison. Time course of spectroscopic readings were analyzed and fitted to the modified Beer-Lambert law. With respect to the placebo readings, we observed (1) significant increases in cerebral concentrations of oxidized CCO (Δ[CCO]; >0.08 µM; p < 0.01), oxygenated hemoglobin (Δ[HbO]; >0.8 µM; p < 0.01), and total hemoglobin (Δ[HbT]; >0.5 µM; p < 0.01) during and after TILS, and (2) linear interplays between Δ[CCO] versus Δ[HbO] and between Δ[CCO] versus Δ[HbT]. Ratios of Δ[CCO]/Δ[HbO] and Δ[CCO]/Δ[HbT] were introduced as TILS-induced metabolic-hemodynamic coupling indices to quantify the coupling strength between TILS-enhanced cerebral metabolism and blood oxygen supply. This study provides the first demonstration that TILS causes up-regulation of oxidized CCO in the human brain, and contributes important insight into the physiological mechanisms.
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Affiliation(s)
- Xinlong Wang
- 1 Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA.,2 Joint Graduate Program between University of Texas at Arlington and UT Southwestern Medical Center at Dallas, University of Texas at Arlington, Arlington, TX, USA
| | - Fenghua Tian
- 1 Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA.,2 Joint Graduate Program between University of Texas at Arlington and UT Southwestern Medical Center at Dallas, University of Texas at Arlington, Arlington, TX, USA
| | - Divya D Reddy
- 1 Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA.,2 Joint Graduate Program between University of Texas at Arlington and UT Southwestern Medical Center at Dallas, University of Texas at Arlington, Arlington, TX, USA
| | - Sahil S Nalawade
- 1 Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA.,2 Joint Graduate Program between University of Texas at Arlington and UT Southwestern Medical Center at Dallas, University of Texas at Arlington, Arlington, TX, USA
| | - Douglas W Barrett
- 3 Department of Psychology and Institute for Neuroscience, the University of Texas at Austin, Austin, TX, USA
| | - Francisco Gonzalez-Lima
- 3 Department of Psychology and Institute for Neuroscience, the University of Texas at Austin, Austin, TX, USA
| | - Hanli Liu
- 1 Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA.,2 Joint Graduate Program between University of Texas at Arlington and UT Southwestern Medical Center at Dallas, University of Texas at Arlington, Arlington, TX, USA
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