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Shali RK, Setarehdan SK, Seifi B. Functional near-infrared spectroscopy based blood pressure variations and hemodynamic activity of brain monitoring following postural changes: A systematic review. Physiol Behav 2024; 281:114574. [PMID: 38697274 DOI: 10.1016/j.physbeh.2024.114574] [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: 12/19/2023] [Revised: 04/03/2024] [Accepted: 04/26/2024] [Indexed: 05/04/2024]
Abstract
Postural change from supine or sitting to standing up leads to displacement of 300 to 1000 mL of blood from the central parts of the body to the lower limb, which causes a decrease in venous return to the heart, hence decrease in cardiac output, causing a drop in blood pressure. This may lead to falling down, syncope, and in general reducing the quality of daily activities, especially in the elderly and anyone suffering from nervous system disorders such as Parkinson's or orthostatic hypotension (OH). Among different modalities to study brain function, functional near-infrared spectroscopy (fNIRS) is a neuroimaging method that optically measures the hemodynamic response in brain tissue. Concentration changes in oxygenated hemoglobin (HbO2) and deoxygenated hemoglobin (HHb) are associated with brain neural activity. fNIRS is significantly more tolerant to motion artifacts compared to fMRI, PET, and EEG. At the same time, it is portable, has a simple structure and usage, is safer, and much more economical. In this article, we systematically reviewed the literature to examine the history of using fNIRS in monitoring brain oxygenation changes caused by sudden changes in body position and its relationship with the blood pressure changes. First, the theory behind brain hemodynamics monitoring using fNIRS and its advantages and disadvantages are presented. Then, a study of blood pressure variations as a result of postural changes using fNIRS is described. It is observed that only 58 % of the references concluded a positive correlation between brain oxygenation changes and blood pressure changes. At the same time, 3 % showed a negative correlation, and 39 % did not show any correlation between them.
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Affiliation(s)
- Roya Kheyrkhah Shali
- School of Electrical and Computer Engineering, College of Engineering, University of Tehran, Tehran, Iran.
| | - Seyed Kamaledin Setarehdan
- School of Electrical and Computer Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Behjat Seifi
- Faculty of Medical Science, University of Tehran, Tehran, Iran
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2
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Scheutz M, Aeron S, Aygun A, de Ruiter JP, Fantini S, Fernandez C, Haga Z, Nguyen T, Lyu B. Estimating Systemic Cognitive States from a Mixture of Physiological and Brain Signals. Top Cogn Sci 2024; 16:485-526. [PMID: 37389823 DOI: 10.1111/tops.12669] [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: 04/26/2021] [Revised: 05/16/2023] [Accepted: 05/16/2023] [Indexed: 07/01/2023]
Abstract
As human-machine teams are being considered for a variety of mixed-initiative tasks, detecting and being responsive to human cognitive states, in particular systematic cognitive states, is among the most critical capabilities for artificial systems to ensure smooth interactions with humans and high overall team performance. Various human physiological parameters, such as heart rate, respiration rate, blood pressure, and skin conductance, as well as brain activity inferred from functional near-infrared spectroscopy or electroencephalogram, have been linked to different systemic cognitive states, such as workload, distraction, or mind-wandering among others. Whether these multimodal signals are indeed sufficient to isolate such cognitive states across individuals performing tasks or whether additional contextual information (e.g., about the task state or the task environment) is required for making appropriate inferences remains an important open problem. In this paper, we introduce an experimental and machine learning framework for investigating these questions and focus specifically on using physiological and neurophysiological measurements to learn classifiers associated with systemic cognitive states like cognitive load, distraction, sense of urgency, mind wandering, and interference. Specifically, we describe a multitasking interactive experimental setting used to obtain a comprehensive multimodal data set which provided the foundation for a first evaluation of various standard state-of-the-art machine learning techniques with respect to their effectiveness in inferring systemic cognitive states. While the classification success of these standard methods based on just the physiological and neurophysiological signals across subjects was modest, which is to be expected given the complexity of the classification problem and the possibility that higher accuracy rates might not in general be achievable, the results nevertheless can serve as a baseline for evaluating future efforts to improve classification, especially methods that take contextual aspects such as task and environmental states into account.
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Affiliation(s)
| | - Shuchin Aeron
- Department of Electrical and Computer Engineering, Tufts University
| | - Ayca Aygun
- Department of Computer Science, Tufts University
| | - J P de Ruiter
- Department of Computer Science, Tufts University
- Department of Psychology, Tufts University
| | | | | | - Zachary Haga
- Department of Computer Science, Tufts University
| | - Thuan Nguyen
- Department of Computer Science, Tufts University
| | - Boyang Lyu
- Department of Electrical and Computer Engineering, Tufts University
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3
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Canova D, Roatta S, Saglietto A, Scarsoglio S, Gianotto NR, Piccotti A, De Ferrari GM, Ridolfi L, Anselmino M. A Quantitative Assessment of Cerebral Hemodynamic Perturbations Associated with Long R-R Intervals in Atrial Fibrillation: A Pilot-Case-Based Experience. MEDICINA (KAUNAS, LITHUANIA) 2024; 60:531. [PMID: 38674177 PMCID: PMC11052310 DOI: 10.3390/medicina60040531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 02/08/2024] [Accepted: 03/18/2024] [Indexed: 04/28/2024]
Abstract
Background and Objectives: Atrial fibrillation (AF) results in systemic hemodynamic perturbations which impact cerebral circulation, possibly contributing to the development of dementia. However, evidence documenting effects in cerebral perfusion is scarce. The aim of this study is to provide a quantitative characterization of the magnitude and time course of the cerebral hemodynamic response to the short hypotensive events associated with long R-R intervals, as detected by near-infrared spectroscopy (NIRS). Materials and Methods: Cerebral NIRS signals and arterial blood pressure were continuously recorded along with an electrocardiogram in twelve patients with AF undergoing elective electrical cardioversion (ECV). The top 0.5-2.5% longest R-R intervals during AF were identified in each patient and used as triggers to carry out the triggered averaging of hemodynamic signals. The average curves were then characterized in terms of the latency, magnitude, and duration of the observed effects, and the possible occurrence of an overshoot was also investigated. Results: The triggered averages revealed that long R-R intervals produced a significant drop in diastolic blood pressure (-13.7 ± 6.1 mmHg) associated with an immediate drop in cerebral blood volume (THI: -0.92 ± 0.46%, lasting 1.9 ± 0.8 s), followed by a longer-lasting decrease in cerebral oxygenation (TOI: -0.79 ± 0.37%, lasting 5.2 ± 0.9 s, p < 0.01). The recovery of the TOI was generally followed by an overshoot (+1.06 ± 0.12%). These effects were progressively attenuated in response to R-R intervals of a shorter duration. Conclusions: Long R-R intervals cause a detectable and consistent cerebral hemodynamic response which concerns both cerebral blood volume and oxygenation and outlasts the duration of the systemic perturbation. These effects are compatible with the activation of dynamic autoregulatory mechanisms in response to the hypotensive stimulus.
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Affiliation(s)
- Daniela Canova
- Department of Neuroscience, University of Torino, 10125 Torino, Italy; (D.C.); (S.R.)
| | - Silvestro Roatta
- Department of Neuroscience, University of Torino, 10125 Torino, Italy; (D.C.); (S.R.)
| | - Andrea Saglietto
- Division of Cardiology, Cardiovascular and Thoracic Department, “Città della Salute e della Scienza” Hospital, 10126 Torino, Italy;
| | - Stefania Scarsoglio
- Department of Water Engineering, Politecnico di Torino, 10129 Torino, Italy;
| | - Nefer Roberta Gianotto
- Department of Medical Sciences, University of Torino, 10124 Torino, Italy; (N.R.G.); (A.P.); (G.M.D.F.)
| | - Alessandro Piccotti
- Department of Medical Sciences, University of Torino, 10124 Torino, Italy; (N.R.G.); (A.P.); (G.M.D.F.)
| | - Gaetano Maria De Ferrari
- Department of Medical Sciences, University of Torino, 10124 Torino, Italy; (N.R.G.); (A.P.); (G.M.D.F.)
| | - Luca Ridolfi
- Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino DIATI, 10129 Torino, Italy;
| | - Matteo Anselmino
- Division of Cardiology, Cardiovascular and Thoracic Department, “Città della Salute e della Scienza” Hospital, 10126 Torino, Italy;
- Department of Medical Sciences, University of Torino, 10124 Torino, Italy; (N.R.G.); (A.P.); (G.M.D.F.)
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Zhang J, Li W, Zhang K, Huo C, Xu G, Li Z. Blood pressure-cerebral oxygen coupling model: A new approach for stroke risk prediction. JOURNAL OF BIOPHOTONICS 2024; 17:e202300318. [PMID: 37795638 DOI: 10.1002/jbio.202300318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/11/2023] [Accepted: 10/04/2023] [Indexed: 10/06/2023]
Abstract
Stroke is a major cause of death and disability worldwide, but predicting its risk remains challenging. This study aimed to evaluate the cerebral blood flow autoregulation function of subjects with different stroke risk levels and predict their stroke risk. The coupling strength between cerebral oxygen and blood pressure signals was calculated by wavelet analysis and dynamic Bayesian inference and used as a quantitative index of cerebral blood flow autoregulation. A stroke prediction model based on the extreme random tree was constructed using the coupling strength and other data as input features. The results showed that the coupling strength was significantly higher in the high-risk group than the other groups. Moreover, the prediction model achieved an average accuracy of 0.80 across the three groups. The coupling strength of cerebral oxygen and blood pressure can be used as an objective index to predict stroke risk, which has implications for stroke prevention and intervention.
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Affiliation(s)
- Jingsha Zhang
- Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age Disability, National Research Center for Rehabilitation Technical Aids, Beijing, China
- Key Laboratory of Neuro-Functional Information and Rehabilitation Engineering of the Ministry of Civil Affairs, Beijing, China
| | - Wenhao Li
- School of Rehabilitation Engineering, Beijing College of Social Administration, Beijing, China
| | - Ke Zhang
- Nanchang City Key Laboratory of Integrated Medical and Industrial Technology, Nanchang University, Nanchang, China
| | - Congcong Huo
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Gongcheng Xu
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Zengyong Li
- Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age Disability, National Research Center for Rehabilitation Technical Aids, Beijing, China
- Key Laboratory of Neuro-Functional Information and Rehabilitation Engineering of the Ministry of Civil Affairs, Beijing, China
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Kim HJ, Lee D, Ri HS, Choi J, Choi J, Rhee SJ, Baik J, Hwang BY, Park G, Cha J, Lee SD. Objective Assessment of Perioperative Anxiety using Functional Near-infrared Spectroscopy in Elderly Patients: A Prospective Randomized Observational Pilot Study. Int J Med Sci 2023; 20:1763-1773. [PMID: 37928873 PMCID: PMC10620860 DOI: 10.7150/ijms.89287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 10/16/2023] [Indexed: 11/07/2023] Open
Abstract
Background: Assessing and managing patient anxiety is essential to reduce postoperative complications in elderly patients. However, monitoring patient anxiety objectively is impossible. This study aimed to investigate the correlation between the level of fNIRS signals and anxiety in patients aged 65 and older undergoing artificial joint replacement surgery. Material and Methods: Sixty patients aged ≥65 years scheduled for elective total knee arthroplasty under spinal anesthesia were included. To differentiate the degree of anxiety, the patients were randomly divided into three groups, each consisting of 20 patients (group 1: administered normal saline as a placebo; groups 2 and 3: administered dexmedetomidine at a rate of 0.2 and 0.5 μg/kg/h, respectively, for 10 min). Functional near-infrared spectroscopy was measured continuously for 10 min in each session (session 1: pre-anesthetic period; session 2: immediately after the spinal anesthesia period; session 3: normal saline or dexmedetomidine receiving period) in all patients. Vital signs were measured thrice at 5-min intervals during each session. State-Trait Anxiety Inventory -S (STAI-S) and Ramsay Sedation Scale (RSS) scores were assessed at the end of each session. Results: The STAI-S score was significantly correlated with power of bandwidth (p = 0.034). In addition, the RSS score was significantly correlated with BW 1, 2, and 3 (p = 0.010, p < 0.001, and p = 0.003, respectively). Conclusion: The STAI-S score and BW 3 were significantly correlated, suggesting that fNIRS might help objectively and directly monitor anxiety levels.
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Affiliation(s)
- Hyae Jin Kim
- Department of Anesthesia and Pain Medicine, School of Medicine, Pusan National University, Busan, South Korea
- Department of Anesthesia and Pain Medicine, Biomedical Research Institute, Pusan National University Hospital, Pusan, South Korea
| | - Dowon Lee
- Department of Anesthesia and Pain Medicine, School of Medicine, Pusan National University, Busan, South Korea
- Department of Anesthesia and Pain Medicine, Biomedical Research Institute, Pusan National University Hospital, Pusan, South Korea
| | - Hyun-Su Ri
- Department of Anesthesiology and Pain Medicine, School of Medicine, Kyungpook National University, Daegu, South Korea
| | | | | | - Seung Joon Rhee
- Department of Orthopedic Surgery, Biomedical Research Institute, Pusan National University Hospital, Pusan National University School of Medicine, Busan, South Korea
| | - Jiseok Baik
- Department of Anesthesia and Pain Medicine, School of Medicine, Pusan National University, Busan, South Korea
- Department of Anesthesia and Pain Medicine, Biomedical Research Institute, Pusan National University Hospital, Pusan, South Korea
| | - Boo-young Hwang
- Department of Anesthesia and Pain Medicine, School of Medicine, Pusan National University, Busan, South Korea
- Department of Anesthesia and Pain Medicine, Biomedical Research Institute, Pusan National University Hospital, Pusan, South Korea
| | - Gayoung Park
- Department of Anesthesia and Pain Medicine, School of Medicine, Pusan National University, Busan, South Korea
- Department of Anesthesia and Pain Medicine, Biomedical Research Institute, Pusan National University Hospital, Pusan, South Korea
| | | | - Sang Don Lee
- Department of Urology, Pusan National University Yangsan Hospital, Pusan National University School of Medicine, Yangsan, South Korea
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van der Harst JJ, Elting JWJ, Bokkers RPH, Veeger NJGM, van Donkelaar CE, van den Bergh WM, Metzemaekers JDM, Groen RJM, Mazuri A, Luijckx GJR, van Dijk JMC, Uyttenboogaart M. The Diagnostic Value of Near-Infrared Spectroscopy to Predict Delayed Cerebral Ischemia and Unfavorable Outcome After Subarachnoid Hemorrhage. World Neurosurg 2023; 178:e202-e212. [PMID: 37454906 DOI: 10.1016/j.wneu.2023.07.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 07/07/2023] [Indexed: 07/18/2023]
Abstract
OBJECTIVE Near-infrared spectroscopy (NIRS) is a noninvasive tool to monitor cerebral regional oxygen saturation. Impairment of microvascular circulation with subsequent cerebral hypoxia during delayed cerebral ischemia (DCI) is associated with poor functional outcome after subarachnoid hemorrhage (SAH). Therefore, NIRS could be useful to predict the risk for DCI and functional outcome. However, only limited data are available on NIRS regional cerebral tissue oxygen saturation (rSO2) distribution in SAH. The aim of this study was to compare the distribution of NIRS rSO2 values in patients with nontraumatic SAH with the occurrence of DCI and functional outcome at 2 months. In addition, the predictive value of NIRS rSO2 was compared with the previously validated SAFIRE grade (derived from Size of the aneurysm, Age, FIsher grade, World Federation of Neurosurgical Societies after REsuscitation). METHODS In this study, the rSO2 distribution of patients with and without DCI after SAH was compared. The optimal cutoff points to predict DCI and outcome were assessed, and its predictive value was compared with the SAFIRE grade. RESULTS Of 41 patients, 12 developed DCI, and 9 had unfavorable outcome at 60 days. Prediction of DCI with NIRS had an area under the curve of 0.77 (95% confidence interval 0.62-0.92; P = 0.0028) with an optimal cutoff point of 65% (sensitivity 1.00; specificity 0.45). Prediction of favorable outcome with NIRS had an area under the curve of 0.86 (95% confidence interval 0.74-0.98; P = 0.0003) with an optimal cutoff point of 63% (sensitivity 1.00; specificity 0.63). Regression analysis showed that NIRS rSO2 score is complementary to the SAFIRE grade. CONCLUSIONS NIRS rSO2 monitoring in patients with SAH may improve prediction of DCI and clinical outcome after SAH.
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Affiliation(s)
- J Joep van der Harst
- Department of Neurology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
| | - Jan Willem J Elting
- Department of Neurology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Reinoud P H Bokkers
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Nic J G M Veeger
- Department of Epidemiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Carlina E van Donkelaar
- Department of Neurosurgery, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Walter M van den Bergh
- Department of Critical Care, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Jan D M Metzemaekers
- Department of Neurosurgery, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Rob J M Groen
- Department of Neurosurgery, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Aryan Mazuri
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Gert-Jan R Luijckx
- Department of Neurology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - J Marc C van Dijk
- Department of Neurosurgery, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Maarten Uyttenboogaart
- Department of Neurology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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Yang J, Acharya D, Scammon WB, Schmitt S, Crane EC, Smith MA, Kainerstorfer JM. Cerebrovascular Impedance as a Function of Cerebral Perfusion Pressure. IEEE OPEN JOURNAL OF ENGINEERING IN MEDICINE AND BIOLOGY 2023; 4:96-101. [PMID: 37234191 PMCID: PMC10208597 DOI: 10.1109/ojemb.2023.3236267] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/19/2022] [Accepted: 12/21/2022] [Indexed: 09/30/2023] Open
Abstract
Goal: Cerebrovascular impedance is modulated by a vasoactive autoregulative mechanism in response to changes in cerebral perfusion pressure. Characterization of impedance and the limits of autoregulation are important biomarkers of cerebral health. We developed a method to quantify impedance based on the spectral content of cerebral blood flow and volume at the cardiac frequency, measured with diffuse optical methods. Methods: In three non-human primates, we modulated cerebral perfusion pressure beyond the limits of autoregulation. Cerebral blood flow and volume were measured with diffuse correlation spectroscopy and near-infrared spectroscopy, respectively. Results: We show that impedance can be used to identify the lower and upper limits of autoregulation. Conclusions: This impedance method may be an alternative method to measure autoregulation and a way of assessing cerebral health non-invasively at the clinical bedside.
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Affiliation(s)
- Jason Yang
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
| | - Deepshikha Acharya
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
| | - William B. Scammon
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
| | - Samantha Schmitt
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
- Neuroscience InstituteCarnegie Mellon UniversityPittsburghPA15213USA
| | - Emily C. Crane
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
| | - Matthew A. Smith
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
- Neuroscience InstituteCarnegie Mellon UniversityPittsburghPA15213USA
| | - Jana M. Kainerstorfer
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
- Neuroscience InstituteCarnegie Mellon UniversityPittsburghPA15213USA
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8
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Yang J, Ruesch A, Kainerstorfer JM. Cerebrovascular impedance estimation with near-infrared and diffuse correlation spectroscopy. NEUROPHOTONICS 2023; 10:015002. [PMID: 36699625 PMCID: PMC9868286 DOI: 10.1117/1.nph.10.1.015002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 12/29/2022] [Indexed: 06/17/2023]
Abstract
SIGNIFICANCE Cerebrovascular impedance (CVI) is related to cerebral autoregulation (CA), which is the mechanism of the brain to maintain near-constant cerebral blood flow (CBF) despite changes in cerebral perfusion pressure (CPP). Changes in blood vessel impedance enable the stabilization of blood flow. Due to the interplay between CVI and CA, assessment of CVI may enable quantification of CA and may serve as a biomarker for cerebral health. AIM We developed a method to quantify CVI based on a combination of diffuse correlation spectroscopy (DCS) and continuous wave (CW) near-infrared spectroscopy (NIRS). Data on healthy human volunteers were used to validate the method. APPROACH A combined high-speed DCS-NIRS system was developed, allowing for simultaneous, noninvasive blood flow, and volume measurements in the same tissue compartment. Blood volume was used as a surrogate measurement for blood pressure and CVI was calculated as the spectral ratio of blood volume and blood flow changes. This technique was validated on six healthy human volunteers undergoing postural changes to elicit CVI changes. RESULTS Averaged across the six subjects, a decrease in CVI was found for a head of bed (HOB) tilting of - 40 deg . These impedance changes were reversed when returning to the horizontal (0 deg) HOB baseline. CONCLUSIONS We developed a combined DCS-NIRS system, which measures CBF and volume changes, which we demonstrate can be used to measure CVI. Using CVI as a metric of CA may be beneficial for assessing cerebral health, especially in patients where CPP is altered.
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Affiliation(s)
- Jason Yang
- Carnegie Mellon University, Department of Biomedical Engineering, Pittsburgh, Pennsylvania, United States
| | - Alexander Ruesch
- Carnegie Mellon University, Department of Biomedical Engineering, Pittsburgh, Pennsylvania, United States
- Carnegie Mellon University, Neuroscience Institute, Pittsburgh, Pennsylvania, United States
| | - Jana M. Kainerstorfer
- Carnegie Mellon University, Department of Biomedical Engineering, Pittsburgh, Pennsylvania, United States
- Carnegie Mellon University, Neuroscience Institute, Pittsburgh, Pennsylvania, United States
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Panerai RB, Brassard P, Burma JS, Castro P, Claassen JA, van Lieshout JJ, Liu J, Lucas SJ, Minhas JS, Mitsis GD, Nogueira RC, Ogoh S, Payne SJ, Rickards CA, Robertson AD, Rodrigues GD, Smirl JD, Simpson DM. Transfer function analysis of dynamic cerebral autoregulation: A CARNet white paper 2022 update. J Cereb Blood Flow Metab 2023; 43:3-25. [PMID: 35962478 PMCID: PMC9875346 DOI: 10.1177/0271678x221119760] [Citation(s) in RCA: 42] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Cerebral autoregulation (CA) refers to the control of cerebral tissue blood flow (CBF) in response to changes in perfusion pressure. Due to the challenges of measuring intracranial pressure, CA is often described as the relationship between mean arterial pressure (MAP) and CBF. Dynamic CA (dCA) can be assessed using multiple techniques, with transfer function analysis (TFA) being the most common. A 2016 white paper by members of an international Cerebrovascular Research Network (CARNet) that is focused on CA strove to improve TFA standardization by way of introducing data acquisition, analysis, and reporting guidelines. Since then, additional evidence has allowed for the improvement and refinement of the original recommendations, as well as for the inclusion of new guidelines to reflect recent advances in the field. This second edition of the white paper contains more robust, evidence-based recommendations, which have been expanded to address current streams of inquiry, including optimizing MAP variability, acquiring CBF estimates from alternative methods, estimating alternative dCA metrics, and incorporating dCA quantification into clinical trials. Implementation of these new and revised recommendations is important to improve the reliability and reproducibility of dCA studies, and to facilitate inter-institutional collaboration and the comparison of results between studies.
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Affiliation(s)
- Ronney B Panerai
- Department of Cardiovascular Sciences, University of Leicester and NIHR Biomedical Research Centre, Leicester, UK
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, and Research Center of the Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, QC, Canada
| | - Joel S Burma
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
| | - Pedro Castro
- Department of Neurology, Centro Hospitalar Universitário de São João, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Jurgen Ahr Claassen
- Department of Geriatric Medicine and Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - Johannes J van Lieshout
- Department of Internal Medicine, Amsterdam, UMC, The Netherlands and Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham Medical School, Queen's Medical Centre, UK
| | - Jia Liu
- Institute of Advanced Computing and Digital Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen University Town, Shenzhen, China
| | - Samuel Je Lucas
- School of Sport, Exercise and Rehabilitation Sciences and Centre for Human Brain Health, University of Birmingham, Birmingham, UK
| | - Jatinder S Minhas
- Department of Cardiovascular Sciences, University of Leicester and NIHR Biomedical Research Centre, Leicester, UK
| | - Georgios D Mitsis
- Department of Bioengineering, McGill University, Montreal, Québec, QC, Canada
| | - Ricardo C Nogueira
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil
| | - Shigehiko Ogoh
- Department of Biomedical Engineering, Toyo University, Kawagoe-Shi, Saitama, Japan
| | - Stephen J Payne
- Institute of Applied Mechanics, National Taiwan University, Taipei
| | - Caroline A Rickards
- Department of Physiology & Anatomy, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Andrew D Robertson
- Department of Kinesiology and Health Sciences, University of Waterloo, Waterloo, ON, Canada
| | - Gabriel D Rodrigues
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Jonathan D Smirl
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
| | - David M Simpson
- Institute of Sound and Vibration Research, University of Southampton, Southampton, UK
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Li W, Qu G, Huo C, Hu X, Xu G, Li H, Zhang J, Li Z. Identifying Cognitive Impairment in Elderly Using Coupling Functions Between Cerebral Oxyhemoglobin and Arterial Blood Pressure. Front Aging Neurosci 2022; 14:904108. [PMID: 35669465 PMCID: PMC9163710 DOI: 10.3389/fnagi.2022.904108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 04/29/2022] [Indexed: 11/13/2022] Open
Abstract
Background This study aimed to assess brain oxygenation status and cerebral autoregulation function in subjects with cognitive dysfunction. Methods The Montreal Cognitive Assessment (MoCA) was applied to divide the subjects into three groups: cognitive impairment (Group CI, 72.50 ± 10.93 y), mild cognitive impairment (Group MCI, 72.02 ± 9.90 y), and normal cognition (Group NC, 70.72 ± 7.66 y). Near-infrared spectroscopy technology and a non-invasive blood pressure device were used to simultaneously measure changes in cerebral tissue oxygenation signals in the bilateral prefrontal lobes (LPFC/RPFC) and arterial blood pressure (ABP) signals from subjects in the resting state (15 min). The coupling between ABP and cerebral oxyhemoglobin concentrations (Δ [O2Hb]) was calculated in very-low-frequency (VLF, 0.02-0.07 Hz) and low-frequency (LF, 0.07-0.2 Hz) bands based on the dynamical Bayesian inference approach. Pearson correlation analyses were used to study the relationships between MoCA scores, tissue oxygenation index, and strength of coupling function. Results In the interval VLF, Group CI (p = 0.001) and Group MCI (p = 0.013) exhibited significantly higher coupling strength from ABP to Δ [O2Hb] in the LPFC than Group NC. In the interval LF, coupling strength from ABP to Δ [O2Hb] in the LPFC was significantly higher in Group CI than in Group NC (p = 0.001). Pearson correlation results showed that MoCA scores had a significant positive correlation with the tissue oxygenation index and a significant negative correlation with the coupling strength from ABP to Δ [O2Hb]. Conclusion The significantly increased coupling strength may be evidence of impaired cerebral autoregulation function in subjects with cognitive dysfunction. The Pearson correlation results suggest that indicators of brain oxygenation status and cerebral autoregulation function can reflect cognitive function. This study provides insights into the mechanisms underlying the pathophysiology of cognitive impairment and provides objective indicators for screening cognitive impairment in the elderly population.
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Affiliation(s)
- Wenhao Li
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
- Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, China
| | - Guanwen Qu
- Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age Disability, National Research Center for Rehabilitation Technical Aids, Beijing, China
- Key Laboratory of Neuro-Functional Information and Rehabilitation Engineering of the Ministry of Civil Affairs, Beijing, China
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Congcong Huo
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
- Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, China
| | - Xiaoling Hu
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Gongcheng Xu
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
- Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, China
| | - Huiyuan Li
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
- Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, China
| | - Jingsha Zhang
- Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age Disability, National Research Center for Rehabilitation Technical Aids, Beijing, China
- Key Laboratory of Neuro-Functional Information and Rehabilitation Engineering of the Ministry of Civil Affairs, Beijing, China
| | - Zengyong Li
- Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age Disability, National Research Center for Rehabilitation Technical Aids, Beijing, China
- Key Laboratory of Neuro-Functional Information and Rehabilitation Engineering of the Ministry of Civil Affairs, Beijing, China
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11
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Laws JC, Jordan LC, Pagano LM, Wellons JC, Wolf MS. Multimodal Neurologic Monitoring in Children With Acute Brain Injury. Pediatr Neurol 2022; 129:62-71. [PMID: 35240364 PMCID: PMC8940706 DOI: 10.1016/j.pediatrneurol.2022.01.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 01/04/2022] [Accepted: 01/25/2022] [Indexed: 12/26/2022]
Abstract
Children with acute neurologic illness are at high risk of mortality and long-term neurologic disability. Severe traumatic brain injury, cardiac arrest, stroke, and central nervous system infection are often complicated by cerebral hypoxia, hypoperfusion, and edema, leading to secondary neurologic injury and worse outcome. Owing to the paucity of targeted neuroprotective therapies for these conditions, management emphasizes close physiologic monitoring and supportive care. In this review, we will discuss advanced neurologic monitoring strategies in pediatric acute neurologic illness, emphasizing the physiologic concepts underlying each tool. We will also highlight recent innovations including novel monitoring modalities, and the application of neurologic monitoring in critically ill patients at risk of developing neurologic sequelae.
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Affiliation(s)
- Jennifer C Laws
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Lori C Jordan
- Division of Pediatric Neurology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Lindsay M Pagano
- Division of Pediatric Neurology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - John C Wellons
- Division of Pediatric Neurological Surgery, Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Michael S Wolf
- Division of Pediatric Critical Care Medicine, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee.
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12
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Mol A, Claassen JAHR, Maier AB, van Wezel RJA, Meskers CGM. Determinants of orthostatic cerebral oxygenation assessed using near-infrared spectroscopy. Auton Neurosci 2022; 238:102942. [PMID: 35124323 DOI: 10.1016/j.autneu.2022.102942] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 11/18/2021] [Accepted: 01/16/2022] [Indexed: 11/26/2022]
Abstract
BACKGROUND To understand the relationship between blood pressure changes during standing up and clinical outcome, cerebral oxygenation needs to be measured, which may be performed using near-infrared spectroscopy (NIRS). However, the role of potential determinants of NIRS-derived orthostatic cerebral oxygenation, i.e., age, sex, type of postural change (i.e., standing up from sitting versus supine position), blood pressure (BP) and baroreflex sensitivity (BRS) is still unknown and needed to better interpret findings from studies using orthostatic NIRS measurements. METHODS 34 younger (median age 25 years, inter quartile range (IQR) 22-45) and 31 older adults (median age 77 years, IQR 72-81) underwent BP, BRS and NIRS measurements during standing up from sitting and supine position. Linear regression models were used to assess the potential determinant role of age, sex, type of postural change, BP and BRS in orthostatic cerebral oxygenation drop and recovery. Orthostatic cerebral oxygenation test-retest reliability was assessed using intra class correlations. RESULTS Younger age, male sex and standing up from supine compared to sitting position were positively associated with cerebral oxygenation drop; older age and standing up from sitting compared to supine position were associated with higher cerebral oxygenation recovery. Test-retest reliability was highest (ICC > 0.83) during standing up from supine position. CONCLUSION Based on the findings of this study, age, sex and type of postural change are significant determinants of NIRS-derived orthostatic cerebral oxygenation and should be taken into account in the interpretation of NIRS measurements. In the design of new studies, standing up from supine position is preferable (higher reliability) over standing up from sitting position.
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Affiliation(s)
- Arjen Mol
- Department of Human Movement Sciences, @AgeAmsterdam, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Van der Boechorstraat 9, 1081 BT Amsterdam, the Netherlands; Department of Biophysics, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Heijendaalseweg 135, 6525 AJ Nijmegen, the Netherlands.
| | - Jurgen A H R Claassen
- Department of Geriatric Medicine, Radboud University Medical Center, Reinier Postlaan 4, 6525 GC Nijmegen, the Netherlands
| | - Andrea B Maier
- Department of Human Movement Sciences, @AgeAmsterdam, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Van der Boechorstraat 9, 1081 BT Amsterdam, the Netherlands; Department of Medicine and Aged Care, @AgeMelbourne, The University of Melbourne, The Royal Melbourne Hospital, City Campus, Level 6 North, 300 Grattan Street, Parkville, Victoria 3050, Australia; Yong Loo Lin School of Medicine, National University of Singapore, Centre for Healthy Longevity, National University Health System, 10 Medical Dr, Singapore 117597, Singapore
| | - Richard J A van Wezel
- Department of Biophysics, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Heijendaalseweg 135, 6525 AJ Nijmegen, the Netherlands; Department of Biomedical Signals and Systems, Technical Medical Centre, University of Twente, Zuidhorst Building, P.O. Box 217, 7500 AE Enschede, the Netherlands
| | - Carel G M Meskers
- Department of Rehabilitation Medicine, Amsterdam UMC, Vrije Universiteit, Amsterdam Movement Sciences, P.O. Box 7057, 1007 MB Amsterdam, the Netherlands
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13
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Fan JL, Nogueira RC, Brassard P, Rickards CA, Page M, Nasr N, Tzeng YC. Integrative physiological assessment of cerebral hemodynamics and metabolism in acute ischemic stroke. J Cereb Blood Flow Metab 2022; 42:454-470. [PMID: 34304623 PMCID: PMC8985442 DOI: 10.1177/0271678x211033732] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Restoring perfusion to ischemic tissue is the primary goal of acute ischemic stroke care, yet only a small portion of patients receive reperfusion treatment. Since blood pressure (BP) is an important determinant of cerebral perfusion, effective BP management could facilitate reperfusion. But how BP should be managed in very early phase of ischemic stroke remains a contentious issue, due to the lack of clear evidence. Given the complex relationship between BP and cerebral blood flow (CBF)-termed cerebral autoregulation (CA)-bedside monitoring of cerebral perfusion and oxygenation could help guide BP management, thereby improve stroke patient outcome. The aim of INFOMATAS is to 'identify novel therapeutic targets for treatment and management in acute ischemic stroke'. In this review, we identify novel physiological parameters which could be used to guide BP management in acute stroke, and explore methodologies for monitoring them at the bedside. We outline the challenges in translating these potential prognostic markers into clinical use.
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Affiliation(s)
- Jui-Lin Fan
- Manaaki Mānawa - The Centre for Heart Research, Department of Physiology, Faculty of Medical & Health Sciences, University of Auckland, Auckland, New Zealand
| | - Ricardo C Nogueira
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil.,Neurology Department, Hospital Nove de Julho, São Paulo, Brazil
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada
| | - Caroline A Rickards
- Department of Physiology & Anatomy, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Matthew Page
- Department of Radiology, Wellington Regional Hospital, Wellington, New Zealand
| | - Nathalie Nasr
- Department of Neurology, Toulouse University Hospital, NSERM UMR 1297, Toulouse, France
| | - Yu-Chieh Tzeng
- Wellington Medical Technology Group, Department of Surgery & Anaesthesia, University of Otago, Wellington, New Zealand.,Centre for Translational Physiology, Department of Surgery & Anaesthesia, University of Otago, Wellington, New Zealand
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14
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Khan MNA, Ghafoor U, Yoo HR, Hong KS. Acupuncture enhances brain function in patients with mild cognitive impairment: evidence from a functional-near infrared spectroscopy study. Neural Regen Res 2022; 17:1850-1856. [PMID: 35017448 PMCID: PMC8820726 DOI: 10.4103/1673-5374.332150] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Mild cognitive impairment (MCI) is a precursor to Alzheimer’s disease. It is imperative to develop a proper treatment for this neurological disease in the aging society. This observational study investigated the effects of acupuncture therapy on MCI patients. Eleven healthy individuals and eleven MCI patients were recruited for this study. Oxy- and deoxy-hemoglobin signals in the prefrontal cortex during working-memory tasks were monitored using functional near-infrared spectroscopy. Before acupuncture treatment, working-memory experiments were conducted for healthy control (HC) and MCI groups (MCI-0), followed by 24 sessions of acupuncture for the MCI group. The acupuncture sessions were initially carried out for 6 weeks (two sessions per week), after which experiments were performed again on the MCI group (MCI-1). This was followed by another set of acupuncture sessions that also lasted for 6 weeks, after which the experiments were repeated on the MCI group (MCI-2). Statistical analyses of the signals and classifications based on activation maps as well as temporal features were performed. The highest classification accuracies obtained using binary connectivity maps were 85.7% HC vs. MCI-0, 69.5% HC vs. MCI-1, and 61.69% HC vs. MCI-2. The classification accuracies using the temporal features mean from 5 seconds to 28 seconds and maximum (i.e, max(5:28 seconds)) values were 60.6% HC vs. MCI-0, 56.9% HC vs. MCI-1, and 56.4% HC vs. MCI-2. The results reveal that there was a change in the temporal characteristics of the hemodynamic response of MCI patients due to acupuncture. This was reflected by a reduction in the classification accuracy after the therapy, indicating that the patients’ brain responses improved and became comparable to those of healthy subjects. A similar trend was reflected in the classification using the image feature. These results indicate that acupuncture can be used for the treatment of MCI patients.
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Affiliation(s)
- M N Afzal Khan
- School of Mechanical Engineering, Pusan National University, Busan, Korea
| | - Usman Ghafoor
- School of Mechanical Engineering, Pusan National University, Busan, Korea
| | - Ho-Ryong Yoo
- Department of Neurology Disorders, Dunsan Hospital, Daejeon University, Daejeon, Korea
| | - Keum-Shik Hong
- School of Mechanical Engineering, Pusan National University, Busan, Korea
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15
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Effects of circulatory arrest and cardiopulmonary bypass on cerebral autoregulation in neonatal swine. Pediatr Res 2022; 91:1374-1382. [PMID: 33947997 PMCID: PMC8566324 DOI: 10.1038/s41390-021-01525-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 02/02/2021] [Accepted: 03/18/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND Cerebral autoregulation mechanisms help maintain adequate cerebral blood flow (CBF) despite changes in cerebral perfusion pressure. Impairment of cerebral autoregulation, during and after cardiopulmonary bypass (CPB), may increase risk of neurologic injury in neonates undergoing surgery. In this study, alterations of cerebral autoregulation were assessed in a neonatal swine model probing four perfusion strategies. METHODS Neonatal swine (n = 25) were randomized to continuous deep hypothermic cardiopulmonary bypass (DH-CPB, n = 7), deep hypothermic circulatory arrest (DHCA, n = 7), selective cerebral perfusion (SCP, n = 7) at deep hypothermia, or normothermic cardiopulmonary bypass (control, n = 4). The correlation coefficient (LDx) between laser Doppler measurements of CBF and mean arterial blood pressure was computed at initiation and conclusion of CPB. Alterations in cerebral autoregulation were assessed by the change between initial and final LDx measurements. RESULTS Cerebral autoregulation became more impaired (LDx increased) in piglets that underwent DH-CPB (initial LDx: median 0.15, IQR [0.03, 0.26]; final: 0.45, [0.27, 0.74]; p = 0.02). LDx was not altered in those undergoing DHCA (p > 0.99) or SCP (p = 0.13). These differences were not explained by other risk factors. CONCLUSIONS In a validated swine model of cardiac surgery, DH-CPB had a significant effect on cerebral autoregulation, whereas DHCA and SCP did not. IMPACT Approximately half of the patients who survive neonatal heart surgery with cardiopulmonary bypass (CPB) experience neurodevelopmental delays. This preclinical investigation takes steps to elucidate and isolate potential perioperative risk factors of neurologic injury, such as impairment of cerebral autoregulation, associated with cardiac surgical procedures involving CPB. We demonstrate a method to characterize cerebral autoregulation during CPB pump flow changes in a neonatal swine model of cardiac surgery. Cerebral autoregulation was not altered in piglets that underwent deep hypothermic circulatory arrest (DHCA) or selective cerebral perfusion (SCP), but it was altered in piglets that underwent deep hypothermic CBP.
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16
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Zhang Z, Qi M, Hügli G, Khatami R. Predictors of changes in cerebral perfusion and oxygenation during obstructive sleep apnea. Sci Rep 2021; 11:23510. [PMID: 34873232 PMCID: PMC8648752 DOI: 10.1038/s41598-021-02829-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 11/18/2021] [Indexed: 11/09/2022] Open
Abstract
Obstructive sleep apnea syndrome (OSAS) is a common sleep disorder. Severe OSAS defined as apnea-hypopnea index (AHI) ≥ 30/h is a risk factor for developing cerebro-cardiovascular diseases. The mechanisms of how repetitive sleep apneas/hypopneas damage cerebral hemodynamics are still not well understood. In this study, changes in blood volume (BV) and oxygen saturation (StO2) in the left forehead of 29 newly diagnosed severe OSAS patients were measured by frequency-domain near-infrared spectroscopy during an incremental continuous positive airway pressure (CPAP) titration protocol together with polysomnography. The coefficients of variation of BV (CV-BV) and the decreases of StO2 (de-StO2) of more than 2000 respiratory events were predicted using linear mixed-effect models, respectively. We found that longer events and apneas rather than hypopneas induce larger changes in CV-BV and stronger cerebral desaturation. Respiratory events occurring during higher baseline StO2 before their onsets, during rapid-eye-movement sleep and those associated with higher heart rate induce smaller changes in CV-BV and de-StO2. The stepwise increased CPAP pressures can attenuate these changes. These results suggest that in severe OSAS the length and the type of respiratory event rather than widely used AHI may be better parameters to indicate the severity of cerebral hemodynamic changes.
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Affiliation(s)
- Zhongxing Zhang
- Center for Sleep Medicine, Sleep Research and Epileptology, Clinic Barmelweid AG, 5017, Barmelweid, Switzerland. .,Barmelweid Academy, Clinic Barmelweid AG, Barmelweid, Switzerland.
| | - Ming Qi
- grid.452327.50000 0004 0519 8976Center for Sleep Medicine, Sleep Research and Epileptology, Clinic Barmelweid AG, 5017 Barmelweid, Switzerland
| | - Gordana Hügli
- grid.452327.50000 0004 0519 8976Center for Sleep Medicine, Sleep Research and Epileptology, Clinic Barmelweid AG, 5017 Barmelweid, Switzerland
| | - Ramin Khatami
- grid.452327.50000 0004 0519 8976Center for Sleep Medicine, Sleep Research and Epileptology, Clinic Barmelweid AG, 5017 Barmelweid, Switzerland ,grid.452327.50000 0004 0519 8976Barmelweid Academy, Clinic Barmelweid AG, Barmelweid, Switzerland ,grid.411656.10000 0004 0479 0855Department of Neurology, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland
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17
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Pham T, Fernandez C, Blaney G, Tgavalekos K, Sassaroli A, Cai X, Bibu S, Kornbluth J, Fantini S. Noninvasive Optical Measurements of Dynamic Cerebral Autoregulation by Inducing Oscillatory Cerebral Hemodynamics. Front Neurol 2021; 12:745987. [PMID: 34867729 PMCID: PMC8637213 DOI: 10.3389/fneur.2021.745987] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 10/13/2021] [Indexed: 11/13/2022] Open
Abstract
Objective: Cerebral autoregulation limits the variability of cerebral blood flow (CBF) in the presence of systemic arterial blood pressure (ABP) changes. Monitoring cerebral autoregulation is important in the Neurocritical Care Unit (NCCU) to assess cerebral health. Here, our goal is to identify optimal frequency-domain near-infrared spectroscopy (FD-NIRS) parameters and apply a hemodynamic model of coherent hemodynamics spectroscopy (CHS) to assess cerebral autoregulation in healthy adult subjects and NCCU patients. Methods: In five healthy subjects and three NCCU patients, ABP oscillations at a frequency around 0.065 Hz were induced by cyclic inflation-deflation of pneumatic thigh cuffs. Transfer function analysis based on wavelet transform was performed to measure dynamic relationships between ABP and oscillations in oxy- (O), deoxy- (D), and total- (T) hemoglobin concentrations measured with different FD-NIRS methods. In healthy subjects, we also obtained the dynamic CBF-ABP relationship by using FD-NIRS measurements and the CHS model. In healthy subjects, an interval of hypercapnia was performed to induce cerebral autoregulation impairment. In NCCU patients, the optical measurements of autoregulation were linked to individual clinical diagnoses. Results: In healthy subjects, hypercapnia leads to a more negative phase difference of both O and D oscillations vs. ABP oscillations, which are consistent across different FD-NIRS methods and are highly correlated with a more negative phase difference CBF vs. ABP. In the NCCU, a less negative phase difference of D vs. ABP was observed in one patient as compared to two others, indicating a better autoregulation in that patient. Conclusions: Non-invasive optical measurements of induced phase difference between D and ABP show the strongest sensitivity to cerebral autoregulation. The results from healthy subjects also show that the CHS model, in combination with FD-NIRS, can be applied to measure the CBF-ABP dynamics for a better direct measurement of cerebral autoregulation.
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Affiliation(s)
- Thao Pham
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Cristianne Fernandez
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Giles Blaney
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Kristen Tgavalekos
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Angelo Sassaroli
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Xuemei Cai
- Department of Neurology, Tufts University School of Medicine, Boston, MA, United States
| | - Steve Bibu
- Department of Neurology, Tufts University School of Medicine, Boston, MA, United States
| | - Joshua Kornbluth
- Department of Neurology, Tufts University School of Medicine, Boston, MA, United States
| | - Sergio Fantini
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
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18
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The slope of cerebral oxyhemoglobin oscillation is associated with vascular reserve capacity in large artery steno-occlusion. Sci Rep 2021; 11:8568. [PMID: 33883666 PMCID: PMC8060335 DOI: 10.1038/s41598-021-88198-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 04/05/2021] [Indexed: 11/08/2022] Open
Abstract
Inadequate cerebral perfusion is a risk factor for cerebral ischemia in patients with large artery steno-occlusion. We investigated whether prefrontal oxyhemoglobin oscillation (ΔHbO2, 0.6-2 Hz) was associated with decreased vascular reserve in patients with steno-occlusion in the large anterior circulation arteries. Thirty-six patients with steno-occlusion in the anterior circulation arteries (anterior cerebral artery, middle cerebral artery, and internal carotid artery) were included and compared to thirty-six control subjects. Patients were categorized into two groups (deteriorated vascular reserve vs. preserved vascular reserve) based on the results of Diamox single- photon emission computed tomography imaging. HbO2 data were collected using functional near-infrared spectroscopy. The slope of ΔHbO2 and the ipsilateral/contralateral slope ratio of ΔHbO2 were analyzed. Among the included patients (n = 36), 25 (69.4%) had deteriorated vascular reserve. Patients with deteriorated vascular reserve had a significantly higher average slope of ΔHbO2 on the ipsilateral side (5.01 ± 2.14) and a higher ipsilateral/contralateral ratio (1.44 ± 0.62) compared to those with preserved vascular reserve (3.17 ± 1.36, P = 0.014; 0.93 ± 0.33, P = 0.016, respectively) or the controls (3.82 ± 1.69, P = 0.019; 0.94 ± 0.29, P = 0.001). The ipsilateral/contralateral ΔHbO2 ratio could be used as a surrogate for vascular reserve in patients with severe steno-occlusion in the anterior circulation arteries.
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19
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Cerebral autoregulation assessed by near-infrared spectroscopy: validation using transcranial Doppler in patients with controlled hypertension, cognitive impairment and controls. Eur J Appl Physiol 2021; 121:2165-2176. [PMID: 33860383 PMCID: PMC8260523 DOI: 10.1007/s00421-021-04681-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 04/02/2021] [Indexed: 01/05/2023]
Abstract
PURPOSE Cerebral autoregulation (CA) aims to attenuate the effects of blood pressure variation on cerebral blood flow. This study assessed the criterion validity of CA derived from near-infrared spectroscopy (NIRS) as an alternative for Transcranial Doppler (TCD). METHODS Measurements of continuous blood pressure (BP), oxygenated hemoglobin (O2Hb) using NIRS and cerebral blood flow velocity (CBFV) using TCD (gold standard) were performed in 82 controls, 27 patients with hypertension and 94 cognitively impaired patients during supine rest (all individuals) and repeated sit to stand transitions (cognitively impaired patients). The BP-CBFV and BP-O2Hb transfer function phase shifts (TFφ) were computed as CA measures. Spearman correlations (ρ) and Bland Altman limits of agreement (BAloa) between NIRS- and TCD-derived CA measures were computed. BAloa separation < 50° was considered a high absolute agreement. RESULTS NIRS- and TCD-derived CA estimates were significantly correlated during supine rest (ρ = 0.22-0.30, N = 111-120) and repeated sit-to-stand transitions (ρ = 0.46-0.61, N = 19-32). BAloa separation ranged between 87° and 112° (supine rest) and 65°-77° (repeated sit to stand transitions). CONCLUSION Criterion validity of NIRS-derived CA measures allows for comparison between groups but was insufficient for clinical application in individuals.
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20
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Tran NN, Tran M, Lopez J, Ogbaa M, Votava-Smith JK, Brady KM. Near-Infrared Spectroscopy: Clinical Use in High-Risk Neonates. Neonatal Netw 2021; 40:73-79. [PMID: 33731373 DOI: 10.1891/0730-0832/11-t-678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/06/2020] [Indexed: 11/25/2022]
Abstract
In this review, we describe the near-infrared spectroscopy (NIRS) technology and its clinical use in high-risk neonates in critical care settings. We searched databases (e.g., PubMed, Google Scholar, EBSCOhost) to find studies describing the use of NIRS on critically ill and high-risk neonates. Near-infrared spectroscopy provides continuous noninvasive monitoring of venous oxygen saturation. It uses technology similar to pulse oximetry to measure the oxygen saturation of hemoglobin in a tissue bed to describe the relative delivery and extraction of oxygen. Near-infrared spectroscopy can be a valuable bedside tool to provide clinicians indirect evidence of perfusion. It may prompt early interventions that promote oxygen delivery, which can improve high-risk neonatal outcomes.
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21
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Applegate MB, Gómez CA, Roblyer D. Modulation frequency selection and efficient look-up table inversion for frequency domain diffuse optical spectroscopy. JOURNAL OF BIOMEDICAL OPTICS 2021; 26:JBO-200393RR. [PMID: 33768742 PMCID: PMC7992233 DOI: 10.1117/1.jbo.26.3.036007] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 03/02/2021] [Indexed: 05/02/2023]
Abstract
SIGNIFICANCE Frequency domain diffuse optical spectroscopy (FD-DOS) uses intensity modulated light to measure the absorption and reduced scattering coefficients of turbid media such as biological tissue. Some FD-DOS instruments utilize a single modulation frequency, whereas others use hundreds of frequencies. The effect of modulation frequency choice and measurement bandwidth on optical property (OP) extraction accuracy has not yet been fully characterized. AIM We aim to assess the effect of modulation frequency selection on OP extraction error and develop a high-speed look-up table (LUT) approach for OP estimation. APPROACH We first used noise-free simulations of light transport in homogeneous media to determine optimized iterative inversion model parameters and developed a new multi-frequency LUT method to increase the speed of inversion. We then used experimentally derived noise models for two FD-DOS instruments to generate realistic simulated data for a broad range of OPs and modulation frequencies to test OP extraction accuracy. RESULTS We found that repeated measurements at a single low-frequency (110 MHz) yielded essentially identical OP errors as a broadband frequency sweep (35 evenly spaced frequencies between 50 and 253 MHz) for these noise models. The inclusion of modulation frequencies >300 MHz diminished overall performance for one of the instruments. Additionally, we developed a LUT inversion algorithm capable of increasing inversion speeds by up to 6 × , with 1000 inversions / s and ∼1 % error when a single modulation frequency was used. CONCLUSION These results suggest that simpler single-frequency systems are likely sufficient for many applications and pave the way for a new generation of simpler digital FD-DOS systems capable of rapid, large-volume measurements with real-time feedback.
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Affiliation(s)
- Matthew B. Applegate
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Carlos A. Gómez
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Darren Roblyer
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
- Address all correspondence to Darren Roblyer,
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Li W, Zhang M, Huo C, Xu G, Chen W, Wang D, Li Z. Time-evolving coupling functions for evaluating the interaction between cerebral oxyhemoglobin and arterial blood pressure with hypertension. Med Phys 2021; 48:2027-2037. [PMID: 33253413 DOI: 10.1002/mp.14627] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 10/21/2020] [Accepted: 11/19/2020] [Indexed: 11/08/2022] Open
Abstract
PURPOSES This study aimed to investigate the network coupling between arterial blood pressure (ABP) and changes in cerebral oxyhemoglobin concentration (Δ [O2 Hb]/Δ [HHb]) oscillations based on dynamical Bayesian inference in hypertensive subjects. METHODS Two groups of subjects, consisting of 30 healthy (Group Control, 55.1 ± 10.6 y), and 32 hypertensive individuals (Group AH, 58.9 ± 8.7 y), participated in this study. A functional near-infrared spectroscopy system was used to measure the Δ [O2 Hb] and Δ [HHb] signals in the bilateral prefrontal cortex (LPFC/RPFC), motor cortex (LMC/RMC), and occipital lobe (LOL/ROL) during the resting state (12 min). Based on continuous wavelet analysis and coupling functions, the directed coupling strength (CS) between ABP and cerebral hemoglobin was identified and analyzed in three frequency intervals (I: 0.6-2 Hz, II: 0.145-0.6 Hz, III: 0.01-0.08 Hz). The Pearson correlations between the CS and blood pressure parameters were calculated in the hypertension group. RESULTS In interval I, Group AH exhibited a significantly higher CS for the coupling from ABP to Δ [O2 Hb] than Group Control in LMC, RMC, LOL, and ROL. In interval III, the CS from ABP to Δ [O2 Hb] in LPFC, RPFC, LMC, RMC, LOL, and ROL was significantly higher in Group AH than in Group Control. For the patients with hypertension, diastolic blood pressure was negatively and pulse pressure was positively related to the CS from ABP to Δ [O2 Hb] oscillations in interval III. CONCLUSIONS The higher CS from ABP to Δ [O2 Hb] in interval I indicated that the components of cardiac activity in cerebral hemoglobin oscillations were more directly responsive to the changes in systematic ABP in patients with hypertension than in healthy subjects. Meanwhile, the higher CS from ABP to Δ [O2 Hb] in interval III indicated that the cerebral hemoglobin oscillations were susceptible to changes in blood pressure in hypertensive subjects. The results may serve as evidence of impairment in cerebral autoregulation after hypertension. The Pearson correlation results showed that diastolic blood pressure and pulse pressure might be regarded as predictors of cerebral autoregulation function in patients with hypertension, and may be useful for hypertension stratification. This study provides novel insights into the interaction mechanism between ABP and cerebral hemodynamics and could help in the development of new assessment techniques for cerebral vascular disease.
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Affiliation(s)
- Wenhao Li
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100191, China.,Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, 100083, China
| | - Ming Zhang
- Interdisciplinary Division of Biomedical Engineering, Faculty of Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
| | - Congcong Huo
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100191, China.,Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, 100083, China
| | - Gongcheng Xu
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100191, China.,Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, 100083, China
| | - Wei Chen
- Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age Disability, National Research Center for Rehabilitation Technical Aids, Beijing, 100176, China.,Key Laboratory of Neuro-functional Information and Rehabilitation Engineering of the Ministry of Civil Affairs, Beijing, 100176, China
| | - Daifa Wang
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100191, China.,Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, 100083, China
| | - Zengyong Li
- Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age Disability, National Research Center for Rehabilitation Technical Aids, Beijing, 100176, China.,Key Laboratory of Neuro-functional Information and Rehabilitation Engineering of the Ministry of Civil Affairs, Beijing, 100176, China
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23
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Pham T, Blaney G, Sassaroli A, Fernandez C, Fantini S. Sensitivity of frequency-domain optical measurements to brain hemodynamics: simulations and human study of cerebral blood flow during hypercapnia. BIOMEDICAL OPTICS EXPRESS 2021; 12:766-789. [PMID: 33680541 PMCID: PMC7901322 DOI: 10.1364/boe.412766] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/04/2020] [Accepted: 12/16/2020] [Indexed: 05/20/2023]
Abstract
This study characterizes the sensitivity of noninvasive measurements of cerebral blood flow (CBF) by using frequency-domain near-infrared spectroscopy (FD-NIRS) and coherent hemodynamics spectroscopy (CHS). We considered six FD-NIRS methods: single-distance intensity and phase (SDI and SDϕ), single-slope intensity and phase (SSI and SSϕ), and dual-slope intensity and phase (DSI and DSϕ). Cerebrovascular reactivity (CVR) was obtained from the relative change in measured CBF during a step hypercapnic challenge. Greater measured values of CVR are assigned to a greater sensitivity to cerebral hemodynamics. In a first experiment with eight subjects, CVRSDϕ was greater than CVRSDI (p < 0.01), whereas CVRDSI and CVRDSϕ showed no significant difference (p > 0.5). In a second experiment with four subjects, a 5 mm scattering layer was added between the optical probe and the scalp tissue to increase the extracerebral layer thickness (L ec ), which caused CVRDSϕ to become significantly greater than CVRDSI (p < 0.05). CVRSS measurements yielded similar results as CVRDS measurements but with a greater variability, possibly resulting from instrumental artifacts in SS measurements. Theoretical simulations with two-layered media confirmed that, if the top (extracerebral) layer is more scattering than the bottom (brain) layer, the relative values of CVRDSI and CVRDSϕ depend on L ec . Specifically, the sensitivity to the brain is greater for DSI than DSϕ for a thin extracerebral layer (L ec < 13 mm), whereas it is greater for DSϕ than DSI for a thicker extracerebral layer.
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Affiliation(s)
- Thao Pham
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, MA 02155, USA
| | - Giles Blaney
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, MA 02155, USA
| | - Angelo Sassaroli
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, MA 02155, USA
| | - Cristianne Fernandez
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, MA 02155, USA
| | - Sergio Fantini
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, MA 02155, USA
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24
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Ruesch A, Acharya D, Schmitt S, Yang J, Smith MA, Kainerstorfer JM. Comparison of static and dynamic cerebral autoregulation under anesthesia influence in a controlled animal model. PLoS One 2021; 16:e0245291. [PMID: 33418561 PMCID: PMC7794034 DOI: 10.1371/journal.pone.0245291] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 12/25/2020] [Indexed: 12/30/2022] Open
Abstract
The brain’s ability to maintain cerebral blood flow approximately constant despite cerebral perfusion pressure changes is known as cerebral autoregulation (CA) and is governed by vasoconstriction and vasodilation. Cerebral perfusion pressure is defined as the pressure gradient between arterial blood pressure and intracranial pressure. Measuring CA is a challenging task and has created a variety of evaluation methods, which are often categorized as static and dynamic CA assessments. Because CA is quantified as the performance of a regulatory system and no physical ground truth can be measured, conflicting results are reported. The conflict further arises from a lack of healthy volunteer data with respect to cerebral perfusion pressure measurements and the variety of diseases in which CA ability is impaired, including stroke, traumatic brain injury and hydrocephalus. To overcome these differences, we present a healthy non-human primate model in which we can control the ability to autoregulate blood flow through the type of anesthesia (isoflurane vs fentanyl). We show how three different assessment methods can be used to measure CA impairment, and how static and dynamic autoregulation compare under challenges in intracranial pressure and blood pressure. We reconstructed Lassen’s curve for two groups of anesthesia, where only the fentanyl anesthetized group yielded the canonical shape. Cerebral perfusion pressure allowed for the best distinction between the fentanyl and isoflurane anesthetized groups. The autoregulatory response time to induced oscillations in intracranial pressure and blood pressure, measured as the phase lag between intracranial pressure and blood pressure, was able to determine autoregulatory impairment in agreement with static autoregulation. Static and dynamic CA both show impairment in high dose isoflurane anesthesia, while low isoflurane in combination with fentanyl anesthesia maintains CA, offering a repeatable animal model for CA studies.
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Affiliation(s)
- Alexander Ruesch
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Deepshikha Acharya
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Samantha Schmitt
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Jason Yang
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Matthew A Smith
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Jana M Kainerstorfer
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
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25
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Ruesch A, Schmitt S, Yang J, Smith MA, Kainerstorfer JM. Fluctuations in intracranial pressure can be estimated non-invasively using near-infrared spectroscopy in non-human primates. J Cereb Blood Flow Metab 2020; 40:2304-2314. [PMID: 31775565 PMCID: PMC7585930 DOI: 10.1177/0271678x19891359] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Intracranial pressure (ICP) is typically measured invasively through a sensor placed inside the brain or a needle inserted into the spinal canal, limiting the patient population on which this assessment can be performed. Currently, non-invasive methods are limited due to lack of sensitivity and thus only apply to extreme cases of increased ICP, instead of use in general clinical practice. We demonstrate a novel application for near-infrared spectroscopy (NIRS) to accurately estimate ICP changes over time. Using a non-human primate (Rhesus Macaque) model, we collected optical data while we induced ICP oscillations at multiple ICP levels obtained by manipulating the height of a fluid column connected via a catheter to the lateral ventricle. Hemodynamic responses to ICP changes were measured at the occipital pole and compared to changes detected by a conventional intraparenchymal ICP probe. We demonstrate that hemoglobin concentrations are highly correlated with induced ICP oscillations and that this response is frequency dependent. We translated the NIRS data into non-invasive ICP measurements via a fitted non-parametric transfer function, demonstrating a match in both magnitude and time alignment with an invasively measured reference. Our results demonstrate that NIRS has the potential for non-invasive ICP monitoring.
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Affiliation(s)
- Alexander Ruesch
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Samantha Schmitt
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA.,Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jason Yang
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Matthew A Smith
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA.,Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA.,Carnegie Mellon Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Jana M Kainerstorfer
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA.,Carnegie Mellon Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
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26
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Renesme L, Dumas de la Roque E, Germain C, Chevrier A, Rebola M, Cramaregeas S, Benard A, Elleau C, Tandonnet O. Nasal high-frequency percussive ventilation vs nasal continuous positive airway pressure in newborn infants respiratory distress: A cross over clinical trial. Pediatr Pulmonol 2020; 55:2617-2623. [PMID: 32609946 DOI: 10.1002/ppul.24935] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 06/26/2020] [Indexed: 11/10/2022]
Abstract
OBJECTIVE To determine if nasal high-frequency percussive ventilation (nHFPV) to manage neonatal respiratory distress decreases the regional cerebral oxygen saturation (rScO2 ) compared to nasal continous positive airway pressure (nCPAP). STUDY DESIGN A prospective, randomized, monocentric, open-label, noninferiority crossover trial. Newborns of gestational age (GA) ≥ 33 weeks exhibiting persistent respiratory distress after 10 minutes of life were treated with nHFPV and nCPAP, in succession and in random order. The primary endpoint was the mean rScO2 , as revealed by near-infrared spectroscopy (NIRS). RESULTS Forty-nine newborns were randomized; the mean GA and birth weight was 36.4 ± 1.9 weeks and 2718 ± 497 g. The mean rScO2 difference during the last 5 minutes of each ventilation mode (nHFPV minus nCPAP) was -0.7 ± 5.4% (95% confidence interval (CI) -2.25; 0.95%). CONCLUSION In our study on newborns of GA ≥33 weeks treated for respiratory distress, cerebral oxygenation via nHFPV was not inferior to nCPAP.
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Affiliation(s)
- Laurent Renesme
- Neonatal Intensive Care Unit, University Hospital of Bordeaux, Bordeaux, France
| | | | - Christine Germain
- Pôle de Santé Publique, Clinical Epidemiology Unit, University Hospital of Bordeaux, Bordeaux, France
| | - Agnès Chevrier
- Neonatal Intensive Care Unit, University Hospital of Bordeaux, Bordeaux, France
| | - Muriel Rebola
- Neonatal Intensive Care Unit, University Hospital of Bordeaux, Bordeaux, France
| | - Sophie Cramaregeas
- Neonatal Intensive Care Unit, University Hospital of Bordeaux, Bordeaux, France
| | - Antoine Benard
- Pôle de Santé Publique, Clinical Epidemiology Unit, University Hospital of Bordeaux, Bordeaux, France
| | - Christophe Elleau
- Neonatal Intensive Care Unit, University Hospital of Bordeaux, Bordeaux, France
| | - Olivier Tandonnet
- Neonatal Intensive Care Unit, University Hospital of Bordeaux, Bordeaux, France
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27
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Milej D, Shahid M, Abdalmalak A, Rajaram A, Diop M, St. Lawrence K. Characterizing dynamic cerebral vascular reactivity using a hybrid system combining time-resolved near-infrared and diffuse correlation spectroscopy. BIOMEDICAL OPTICS EXPRESS 2020; 11:4571-4585. [PMID: 32923065 PMCID: PMC7449704 DOI: 10.1364/boe.392113] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/28/2020] [Accepted: 05/12/2020] [Indexed: 05/09/2023]
Abstract
This study presents the characterization of dynamic cerebrovascular reactivity (CVR) in healthy adults by a hybrid optical system combining time-resolved (TR) near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS). Blood flow and oxygenation (oxy- and deoxy-hemoglobin) responses to a step hypercapnic challenge were recorded to characterize dynamic and static components of CVR. Data were acquired at short and long source-detector separations (r SD) to assess the impact of scalp hemodynamics, and moment analysis applied to the TR-NIRS to further enhance the sensitivity to the brain. Comparing blood flow and oxygenation responses acquired at short and long r SD demonstrated that scalp contamination distorted the CVR time courses, particularly for oxyhemoglobin. This effect was significantly diminished by the greater depth sensitivity of TR NIRS and less evident in the DCS data due to the higher blood flow in the brain compared to the scalp. The reactivity speed was similar for blood flow and oxygenation in the healthy brain. Given the ease-of-use, portability, and non-invasiveness of this hybrid approach, it is well suited to investigate if the temporal relationship between CBF and oxygenation is altered by factors such as age and cerebrovascular disease.
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Affiliation(s)
- Daniel Milej
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
| | - Marwan Shahid
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
| | - Androu Abdalmalak
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
| | - Ajay Rajaram
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
| | - Mamadou Diop
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
| | - Keith St. Lawrence
- Imaging Program, Lawson Health Research Institute, London, Ontario, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada
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Hurtado-Puerto AM, Nestor K, Eldaief M, Camprodon JA. Safety Considerations for Cerebellar Theta Burst Stimulation. Clin Ther 2020; 42:1169-1190.e1. [PMID: 32674957 DOI: 10.1016/j.clinthera.2020.06.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 06/03/2020] [Accepted: 06/04/2020] [Indexed: 01/01/2023]
Abstract
PURPOSE The cerebellum is an intricate neural structure that orchestrates various cognitive and behavioral functions. In recent years, there has been an increasing interest in neuromodulation of the cerebellum with transcranial magnetic stimulation (TMS) for therapeutic and basic science applications. Theta burst stimulation (TBS) is an efficient and powerful TMS protocol that is able to induce longer-lasting effects with shorter stimulation times compared with traditional TMS. Parameters for cerebellar TBS are traditionally framed in the bounds of TBS to the cerebral cortex, even when the 2 have distinct histologic, anatomical, and functional characteristics. Tolerability limits have not been systematically explored in the literature for this specific application. Therefore, we aimed to determine the stimulation parameters that have been used for cerebellar. TBS to date and evaluate adverse events and adverse effects related to stimulation parameters. METHODS We used PubMed to perform a critical review of the literature based on a systematic review of original research studies published between September 2008 and November 2019 that reported on cerebellar TBS. We recovered information from these publications and communication with authors about the stimulation parameters used and the occurrence of adverse events. FINDINGS We identified 61 research articles on interventions of TBS to the cerebellum. These articles described 3176 active sessions of cerebellar TBS in 1203 individuals, including healthy participants and patients with various neurologic conditions, including brain injuries. Some studies used substantial doses (eg, pulse intensity and number of pulses) in short periods. No serious adverse events were reported. The specific number of patients who experienced adverse events was established for 48 studies. The risk of an adverse event in this population (n = 885) was 4.1%. Adverse events consisted mostly of discomfort attributable to involuntary muscle contractions. Authors used a variety of methods for calculating stimulation dosages, ranging from the long-established reference of electromyography of a hand muscle to techniques that atone for some of the differences between cerebrum and cerebellum. IMPLICATIONS No serious adverse events have been reported for cerebellar TBS. There is no substantial evidence of a tolerable maximal-efficacy stimulation dose in humans. There is no assurance of equivalence in the translation of cortical excitability and stimulation intensities from the cerebral cortex to cerebellar regions. Further research for the stimulation dose in cerebellar TBS is warranted, along with consistent report of adverse events. © 2020 Elsevier HS Journals, Inc.
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Affiliation(s)
- Aura M Hurtado-Puerto
- Laboratory of Neuropsychiatry and Neuromodulation, Massachusetts General Hospital, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Centro de Estudios Cerebrales, Facultad de Ciencias, Universidad del Valle, Cali, Colombia.
| | - Kimberly Nestor
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Mark Eldaief
- Laboratory of Neuropsychiatry and Neuromodulation, Massachusetts General Hospital, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Joan A Camprodon
- Laboratory of Neuropsychiatry and Neuromodulation, Massachusetts General Hospital, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
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29
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Kermorgant M, Nasr N, Czosnyka M, Arvanitis DN, Hélissen O, Senard JM, Pavy-Le Traon A. Impacts of Microgravity Analogs to Spaceflight on Cerebral Autoregulation. Front Physiol 2020; 11:778. [PMID: 32719617 PMCID: PMC7350784 DOI: 10.3389/fphys.2020.00778] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 06/15/2020] [Indexed: 12/16/2022] Open
Abstract
It is well known that exposure to microgravity in astronauts leads to a plethora physiological responses such as headward fluid shift, body unloading, and cardiovascular deconditioning. When astronauts return to Earth, some encounter problems related to orthostatic intolerance. An impaired cerebral autoregulation (CA), which could be compromised by the effects of microgravity, has been proposed as one of the mechanisms responsible for orthostatic intolerance. CA is a homeostatic mechanism that maintains cerebral blood flow for any variations in cerebral perfusion pressure by adapting the vascular tone and cerebral vessel diameter. The ground-based models of microgravity are useful tools for determining the gravitational impact of spaceflight on human body. The head-down tilt bed rest (HDTBR), where the subject remains in supine position at -6 degrees for periods ranging from few days to several weeks is the most commonly used ground-based model of microgravity for cardiovascular deconditioning. head-down bed rest (HDBR) is able to replicate cephalic fluid shift, immobilization, confinement, and inactivity. Dry immersion (DI) model is another approach where the subject remains immersed in thermoneutral water covered with an elastic waterproof fabric separating the subject from the water. Regarding DI, this analog imitates absence of any supporting structure for the body, centralization of body fluids, immobilization and hypokinesia observed during spaceflight. However, little is known about the impact of microgravity on CA. Here, we review the fundamental principles and the different mechanisms involved in CA. We also consider the different approaches in order to assess CA. Finally, we focus on the effects of short- and long-term spaceflight on CA and compare these findings with two specific analogs to microgravity: HDBR and DI.
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Affiliation(s)
- Marc Kermorgant
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France
| | - Nathalie Nasr
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France
- Department of Neurology, Institute for Neurosciences, Toulouse University Hospital, Toulouse, France
| | - Marek Czosnyka
- Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, Cambridge University Hospital, Cambridge, United Kingdom
- Institute of Electronic Systems, Warsaw University of Technology, Warsaw, Poland
| | - Dina N. Arvanitis
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France
| | - Ophélie Hélissen
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France
| | - Jean-Michel Senard
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France
- Department of Clinical Pharmacology, Toulouse University Hospital, Toulouse, France
| | - Anne Pavy-Le Traon
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), Toulouse, France
- Department of Neurology, Institute for Neurosciences, Toulouse University Hospital, Toulouse, France
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30
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Cerebral macro- and microcirculatory blood flow dynamics in successfully treated chronic hypertensive patients with and without white mater lesions. Sci Rep 2020; 10:9213. [PMID: 32514031 PMCID: PMC7280202 DOI: 10.1038/s41598-020-66317-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 05/18/2020] [Indexed: 01/14/2023] Open
Abstract
The mechanisms of high blood pressure (HBP) -related brain pathology progression remain relatively unclear. We investigated whether lowering BP in chronic HBP patients normalizes cerebral perfusion dynamics at resistance vessel and capillary levels. Sixty-seven patients with HBP and 49 age- and sex-matched healthy controls underwent simultaneous recordings of middle cerebral artery blood flow velocity (CBFV), BP, and end-tidal CO2 concentration. Thirty-four controls and 28 patients underwent additional near-infrared spectroscopy recordings (oxygenated [O2Hb] and deoxygenated [HHb] hemoglobin). Degree of microcirculatory white matter lesions was graded by Fazekas scale. Dynamic cerebral autoregulation (dCA) was assessed by transfer function analysis. BP was successfully lowered (patients = 89 ± 15 mm Hg, controls = 87 ± 17), but cerebrovascular resistance was higher in BP patients (p < 0.05). BP-CBFV phase was lower in very low frequency (VLF) (left/right: 48 ± 20°/44 ± 17; controls: 61 ± 20/60 ± 21; p < 0.001) and low frequency (LF) (34 ± 14/35 ± 14; controls: 48 ± 20/44 ± 17; p < 0.05) ranges. Gain was higher in VLF range (in %/ mm Hg 0.56 ± 0.44/0.59 ± 0.49; controls: 0.32 ± 0.29/0.34 ± 0.32; p ≤ 0.005). BP-CBFV phase and gain did not differ across Fazekas groups. Across all patients, the capillary phases and gains (CBFV-[O2Hb], CBFV-[HHb]) were comparable to controls. Successfully treated chronic HBP results in normal brain capillary hemodynamics while the resistance vessel state is disturbed (phase decrease, gain increase).
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Fantini S, Sassaroli A. Frequency-Domain Techniques for Cerebral and Functional Near-Infrared Spectroscopy. Front Neurosci 2020; 14:300. [PMID: 32317921 PMCID: PMC7154496 DOI: 10.3389/fnins.2020.00300] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 03/16/2020] [Indexed: 12/31/2022] Open
Abstract
This article reviews the basic principles of frequency-domain near-infrared spectroscopy (FD-NIRS), which relies on intensity-modulated light sources and phase-sensitive optical detection, and its non-invasive applications to the brain. The simpler instrumentation and more straightforward data analysis of continuous-wave NIRS (CW-NIRS) accounts for the fact that almost all the current commercial instruments for cerebral NIRS have embraced the CW technique. However, FD-NIRS provides data with richer information content, which complements or exceeds the capabilities of CW-NIRS. One example is the ability of FD-NIRS to measure the absolute optical properties (absorption and reduced scattering coefficients) of tissue, and thus the absolute concentrations of oxyhemoglobin and deoxyhemoglobin in brain tissue. This article reviews the measured values of such optical properties and hemoglobin concentrations reported in the literature for animal models and for the human brain in newborns, infants, children, and adults. We also review the application of FD-NIRS to functional brain studies that focused on slower hemodynamic responses to brain activity (time scale of seconds) and faster optical signals that have been linked to neuronal activation (time scale of 100 ms). Another example of the power of FD-NIRS data is related to the different regions of sensitivity featured by intensity and phase data. We report recent developments that take advantage of this feature to maximize the sensitivity of non-invasive optical signals to brain tissue relative to more superficial extracerebral tissue (scalp, skull, etc.). We contend that this latter capability is a highly appealing quality of FD-NIRS, which complements absolute optical measurements and may result in significant advances in the field of non-invasive optical sensing of the brain.
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Affiliation(s)
- Sergio Fantini
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
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Kim TJ, Kim JM, Lee JS, Park SH, Jeong HB, Choi JK, Kim K, Bae HM, Ko SB. Prognostication of neurological outcome after cardiac arrest using wavelet phase coherence analysis of cerebral oxygen. Resuscitation 2020; 150:41-49. [PMID: 32194164 DOI: 10.1016/j.resuscitation.2020.02.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 02/20/2020] [Accepted: 02/24/2020] [Indexed: 01/05/2023]
Abstract
BACKGROUND The prognosis for cardiac arrest (CA) is associated with the degree of cerebral ischemia. We investigated the relationship between the wavelet coherence of cerebral oxyhemoglobin (HbO2) among different channels and outcomes after CA. Moreover, we aimed to develop a prognostication method after CA. METHODS Eighty-three post-resuscitation patients were included. The HbO2 data were collected during the post-resuscitation period (median day, 1) using functional near-infrared spectroscopy. The coherence between sections of prefrontal HbO2 oscillations in five frequency intervals (I, 0.6-2 Hz; II, 0.15-0.6 Hz; III, 0.05-0.15 Hz; IV, 0.02-0.05 Hz; and V, 0.0095-0.02 Hz) were analyzed. We evaluated the outcomes using cerebral performance category (CPC) scores (good outcome, CPC ≤ 2 and poor outcome, CPC ≥ 3) at 3 months after CA. Additionally, the predictive method was developed using the biomarker and coherence value after CA. RESULTS Among the included patients, 19 patients (22.9%) had a good outcome. Poor outcome group had significantly lower phase coherence in the myogenic frequency interval III compared to good outcome group (0.36 ± 0.14 vs. 0.54 ± 0.18, P < 0.001). The predictive method using neuron-specific enolase (NSE) and interval III value demonstrated good discrimination (area under the curve 0.919; 95% confidence interval, 0.850-0.989). CONCLUSIONS The predictive method using NSE and phase coherence of HbO2 in the interval III from the vascular smooth muscle cells could be a useful tool for prognosticating after CA. This suggests that evaluating cerebral ischemia using phase coherence of HbO2 might be a helpful outcome predictor following CA.
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Affiliation(s)
- Tae Jung Kim
- Department of Neurology, Seoul National University Hospital, Seoul, Republic of Korea; Department of Critical Care Medicine, Seoul National University Hospital, Seoul, Republic of Korea
| | - Jae-Myoung Kim
- Department of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Ji Sung Lee
- Clinical Research Center, Asan Medical Center, Seoul, Republic of Korea
| | - Soo-Hyun Park
- Department of Critical Care Medicine, Seoul National University Hospital, Seoul, Republic of Korea
| | - Hae-Bong Jeong
- Department of Neurology, Seoul National University Hospital, Seoul, Republic of Korea
| | - Jong-Kwan Choi
- Department of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Kyuseok Kim
- Department of Emergency Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hyeon-Min Bae
- Department of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Sang-Bae Ko
- Department of Neurology, Seoul National University Hospital, Seoul, Republic of Korea; Department of Critical Care Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
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Mol A, Maier AB, van Wezel RJA, Meskers CGM. Multimodal Monitoring of Cardiovascular Responses to Postural Changes. Front Physiol 2020; 11:168. [PMID: 32194438 PMCID: PMC7063121 DOI: 10.3389/fphys.2020.00168] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 02/13/2020] [Indexed: 12/13/2022] Open
Abstract
Background In the poorly understood relationship between orthostatic hypotension and falls, next to blood pressure (BP), baroreflex sensitivity (BRS) and cerebral autoregulation (CAR) may be key measures. The posture- and movement dependency of orthostatic hypotension requires continuous and unobtrusive monitoring. This may be possible using simultaneous photoplethysmography (PPG), electrocardiography (ECG), and near-infrared spectroscopy (NIRS) signal recordings, from which pulse wave velocity (PWV; potentially useful for BP estimation), BRS and CAR can be derived. The PPG, NIRS and PWV signal correlation with BP and BRS/CAR reliability and validity need to be addressed. Methods In 34 healthy adults (mean age 25 years, inter quartile range 22–45; 10 female), wrist and finger PPG, ECG, bifrontal NIRS (oxygenated and deoxygenated hemoglobin) and continuous BP were recorded during sit to stand and supine to stand movements. Sixteen participants performed slow and rapid supine to stand movements; eighteen other participants performed a 1-min squat movement. Pulse wave velocity (PWV) was defined as the inverse of the ECG R-peak to PPG pulse delay; PPG, NIRS and PWV signal correlation with BP as their Pearson correlations with mean arterial pressure (MAP) within 30 s after the postural changes; BRS as inter beat interval drop divided by systolic BP (SBP) drop during the postural changes; CAR as oxygenated hemoglobin drop divided by MAP drop. BRS and CAR were separately computed using measured and estimated (linear regression) BP. BRS/CAR reliability was defined by the intra class correlation between repeats of the same postural change; validity as the Pearson correlation between BRS/CAR values based on measured and estimated BP. Results The highest correlation with MAP was found for finger PPG and oxygenated hemoglobin, ranging from 0.75–0.79 (sit to stand), 0.66–0.88 (supine to stand), and 0.82–0.94 (1-min squat). BRS and CAR reliability was highest during the different supine to stand movements, ranging from 0.17 – 0.49 (BRS) and 0.42-0.75 (CAR); validity was highest during rapid supine to stand movements, 0.54 and 0.79 respectively. Conclusion PPG-ECG-NIRS recordings showed high correlation with BP and enabled computation of reliable and valid BRS and CAR estimates, suggesting their potential for continuous unobtrusive monitoring of orthostatic hypotension key measures.
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Affiliation(s)
- Arjen Mol
- Department of Human Movement Sciences @AgeAmsterdam, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands.,Department of Biophysics, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, Netherlands
| | - Andrea B Maier
- Department of Human Movement Sciences @AgeAmsterdam, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands.,Department of Medicine and Aged Care @AgeMelbourne, The Royal Melbourne Hospital, The University of Melbourne, Parkville, VIC, Australia
| | - Richard J A van Wezel
- Department of Biophysics, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, Netherlands.,Department of Biomedical Signals and Systems, Technical Medical Centre, University of Twente, Enschede, Netherlands
| | - Carel G M Meskers
- Department of Human Movement Sciences @AgeAmsterdam, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands.,Department of Rehabilitation Medicine, Amsterdam UMC, Amsterdam Movement Sciences, Vrije Universiteit, Amsterdam, Netherlands
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Blaney G, Sassaroli A, Fantini S. Algorithm for determination of thresholds of significant coherence in time-frequency analysis. Biomed Signal Process Control 2020; 56. [DOI: 10.1016/j.bspc.2019.101704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
OBJECTIVE This study applied a new external ventricular catheter, which allows intracranial pressure (ICP) monitoring and cerebral spinal fluid (CSF) drainage simultaneously, to study cerebral vascular responses during acute CSF drainage. METHODS Six patients with 34 external ventricular drain (EVD) opening sessions were retrospectively analyzed. A published algorithm was used to extract morphological features of ICP recordings, and a template-matching algorithm was applied to calculate the likelihood of cerebral vasodilation index (VDI) and cerebral vasoconstriction index (VCI) based on the changes of ICP waveforms during CSF drainage. Power change (∆P) of ICP B-waves after EVD opening was also calculated. Cerebral autoregulation (CA) was assessed through phase difference between arterial blood pressure (ABP) and ICP using a previously published wavelet-based algorithm. RESULTS The result showed that acute CSF drainage reduced mean ICP (P = 0.016) increased VCI (P = 0.02) and reduced ICP B-wave power (P = 0.016) significantly. VCI reacted to ICP changes negatively when ICP was between 10 and 25 mmHg, and VCI remained unchanged when ICP was outside the 10-25 mmHg range. VCI negatively (r = - 0.44) and VDI positively (r = 0.82) correlated with ∆P of ICP B-waves, indicating that stronger vasoconstriction resulted in bigger power drop in ICP B-waves. Better CA prior to EVD opening triggered bigger drop in the power of ICP B-waves (r = - 0.612). CONCLUSIONS This study demonstrates that acute CSF drainage reduces mean ICP, and results in vasoconstriction which can be detected through an index, VCI. Cerebral vessels actively respond to ICP changes or cerebral perfusion pressure (CPP) changes in a certain range; beyond which, the vessels are insensitive to the changes in ICP and CPP.
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Venkatesh I, Shubha HV, Karthik N, RaviShankar S. A Study of reversal of diastolic blood flow in the middle cerebral artery using doppler ultrasound in the prognostication in sick neonates. J Clin Neonatol 2020. [DOI: 10.4103/jcn.jcn_83_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Elting JWJ, Tas J, Aries MJ, Czosnyka M, Maurits NM. Dynamic cerebral autoregulation estimates derived from near infrared spectroscopy and transcranial Doppler are similar after correction for transit time and blood flow and blood volume oscillations. J Cereb Blood Flow Metab 2020; 40:135-149. [PMID: 30353763 PMCID: PMC6927073 DOI: 10.1177/0271678x18806107] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
We analysed mean arterial blood pressure, cerebral blood flow velocity, oxygenated haemoglobin and deoxygenated haemoglobin signals to estimate dynamic cerebral autoregulation. We compared macrovascular (mean arterial blood pressure-cerebral blood flow velocity) and microvascular (oxygenated haemoglobin-deoxygenated haemoglobin) dynamic cerebral autoregulation estimates during three different conditions: rest, mild hypocapnia and hypercapnia. Microvascular dynamic cerebral autoregulation estimates were created by introducing the constant time lag plus constant phase shift model, which enables correction for transit time, blood flow and blood volume oscillations (TT-BF/BV correction). After TT-BF/BV correction, a significant agreement between mean arterial blood pressure-cerebral blood flow velocity and oxygenated haemoglobin-deoxygenated haemoglobin phase differences in the low frequency band was found during rest (left: intraclass correlation=0.6, median phase difference 29.5° vs. 30.7°, right: intraclass correlation=0.56, median phase difference 32.6° vs. 39.8°) and mild hypocapnia (left: intraclass correlation=0.73, median phase difference 48.6° vs. 43.3°, right: intraclass correlation=0.70, median phase difference 52.1° vs. 61.8°). During hypercapnia, the mean transit time decreased and blood volume oscillations became much more prominent, except for very low frequencies. The transit time related to blood flow oscillations was remarkably stable during all conditions. We conclude that non-invasive microvascular dynamic cerebral autoregulation estimates are similar to macrovascular dynamic cerebral autoregulation estimates, after TT-BF/BV correction is applied. These findings may increase the feasibility of non-invasive continuous autoregulation monitoring and guided therapy in clinical situations.
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Affiliation(s)
- Jan Willem J Elting
- Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands
| | - Jeanette Tas
- Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands
| | - Marcel Jh Aries
- Department of Intensive Care, Maastricht University Medical Center, Maastricht, The Netherlands.,Brain Physics Group, Department of Clinical Neurosciences, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
| | - Marek Czosnyka
- Brain Physics Group, Department of Clinical Neurosciences, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK.,Institute of Electronic Systems, Warsaw University of Technology, Warsaw, Poland
| | - Natasha M Maurits
- Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands
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Amyot F, Kenney K, Spessert E, Moore C, Haber M, Silverman E, Gandjbakhche A, Diaz-Arrastia R. Assessment of cerebrovascular dysfunction after traumatic brain injury with fMRI and fNIRS. Neuroimage Clin 2019; 25:102086. [PMID: 31790877 PMCID: PMC6909332 DOI: 10.1016/j.nicl.2019.102086] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 11/07/2019] [Accepted: 11/09/2019] [Indexed: 11/26/2022]
Abstract
Traumatic cerebral vascular injury (TCVI) is a frequent, but under-recognized, endophenotype of traumatic brain injury (TBI). It likely contributes to functional deficits after TBI and TBI-related chronic disability, and represents an attractive target for targeted therapeutic interventions. The aim of this prospective study is to assess microvascular injury/dysfunction in chronic TBI by measuring cerebral vascular reactivity (CVR) by 2 methods, functional magnetic resonance imaging (fMRI) and functional Near InfraRed Spectroscopy (fNIRS) imaging, as each has attractive features relevant to clinical utility. 42 subjects (27 chronic TBI, 15 age- and gender-matched non-TBI volunteers) were enrolled and underwent outpatient CVR testing by 2 methods, MRI-BOLD and fNIRS, each with hypercapnia challenge, a neuropsychological testing battery, and symptom survey questionnaires. Chronic TBI subjects showed a significant reduction in global CVR compared to HC (p < 0.0001). Mean CVR measures by fMRI were 0.225 ± 0.014 and 0.183 ± 0.026 %BOLD/mmHg for non-TBI and TBI subjects respectively and 12.3 ± 1.8 and 9.2 ± 1.7 mM/mmHg by fNIRS for non-TBI versus TBI subjects respectively. Global CVR measured by fNIRS imaging correlates with results by MRI-BOLD (R = 0.5). Focal CVR deficits seen on CVR maps by fMRI are also observed in the same areas by fNIRS in the frontal regions. Global CVR is significantly lower in chronic TBI patients and is reliably measured by both fMRI and fNIRS, the former with better spatial and the latter with better temporal resolution. Both methods show promise as non-invasive measures of CVR function and microvascular integrity after TBI.
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Affiliation(s)
- Franck Amyot
- Department of Neurology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA; Center for Neuroscience and Regenerative Medicine, Department of Neurology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
| | - Kimbra Kenney
- Department of Neurology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA; Center for Neuroscience and Regenerative Medicine, Department of Neurology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA
| | - Emily Spessert
- Department of Neurology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA; Center for Neuroscience and Regenerative Medicine, Department of Neurology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA
| | - Carol Moore
- Department of Neurology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA; Center for Neuroscience and Regenerative Medicine, Department of Neurology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA
| | - Margalit Haber
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - Erika Silverman
- Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia
| | - Amir Gandjbakhche
- Section on Analytical and Functional Biophotonics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Ramon Diaz-Arrastia
- Center for Neuroscience and Regenerative Medicine, Department of Neurology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA; Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia
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Ghafoor U, Lee JH, Hong KS, Park SS, Kim J, Yoo HR. Effects of Acupuncture Therapy on MCI Patients Using Functional Near-Infrared Spectroscopy. Front Aging Neurosci 2019; 11:237. [PMID: 31543811 PMCID: PMC6730485 DOI: 10.3389/fnagi.2019.00237] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/16/2019] [Indexed: 01/25/2023] Open
Abstract
Acupuncture therapy (AT) is a non-pharmacological method of treatment that has been applied to various neurological diseases. However, studies on its longitudinal effect on the neural mechanisms of patients with mild cognitive impairment (MCI) for treatment purposes are still lacking in the literature. In this clinical study, we assess the longitudinal effects of ATs on MCI patients using two methods: (i) Montreal Cognitive Assessment test (MoCA-K, Korean version), and (ii) the hemodynamic response (HR) analyses using functional near-infrared spectroscopy (fNIRS). fNIRS signals of a working memory (WM) task were acquired from the prefrontal cortex. Twelve elderly MCI patients and 12 healthy people were recruited as target and healthy control (HC) groups, respectively. Each group went through an fNIRS scanning procedure three times: The initial data were obtained without any ATs, and subsequently a total of 24 AT sessions were conducted for MCI patients (i.e., MCI-0: the data prior to ATs, MCI-1: after 12 sessions of ATs for 6 weeks, MCI-2: another 12 sessions of ATs for 6 weeks). The mean HR responses of all MCI-0–2 cases were lower than those of HCs. To compare the effects of AT on MCI patients, MoCA-K results, temporal HR data, and spatial activation patterns (i.e., t-maps) were examined. In addition, analyses of functional connectivity (FC) and graph theory upon WM tasks were conducted. With ATs, (i) the averaged MoCA-K test scores were improved (MCI-1, p = 0.002; MCI-2, p = 2.9e–4); (ii) the mean HR response of WM tasks was increased (p < 0.001); and (iii) the t-maps of MCI-1 and MCI-2 were enhanced. Furthermore, an increased FC in the prefrontal cortex in both MCI-1/MCI-2 cases in comparison to MCI-0 was obtained (p < 0.01), and an increasing trend in the graph theory parameters was observed. All these findings reveal that ATs have a positive impact on improving the cognitive function of MCI patients. In conclusion, ATs can be used as a therapeutic tool for MCI patients as a non-pharmacological method (Clinical trial registration number: KCT 0002451 https://cris.nih.go.kr/cris/en/).
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Affiliation(s)
- Usman Ghafoor
- School of Mechanical Engineering, Pusan National University, Busan, South Korea
| | - Jun-Hwan Lee
- Clinical Medicine Division, Korea Institute of Oriental Medicine, Daejeon, South Korea
| | - Keum-Shik Hong
- School of Mechanical Engineering, Pusan National University, Busan, South Korea
| | - Sang-Soo Park
- Korean Medicine Clinical Trial Center, Korean Medicine Hospital, Daejeon University, Daejeon, South Korea
| | - Jieun Kim
- Clinical Medicine Division, Korea Institute of Oriental Medicine, Daejeon, South Korea
| | - Ho-Ryong Yoo
- Department of Neurology Disorders, Dunsan Hospital, Daejeon University, Daejeon, South Korea
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40
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Sandsmark DK, Bashir A, Wellington CL, Diaz-Arrastia R. Cerebral Microvascular Injury: A Potentially Treatable Endophenotype of Traumatic Brain Injury-Induced Neurodegeneration. Neuron 2019; 103:367-379. [PMID: 31394062 PMCID: PMC6688649 DOI: 10.1016/j.neuron.2019.06.002] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/10/2019] [Accepted: 06/03/2019] [Indexed: 02/08/2023]
Abstract
Traumatic brain injury (TBI) is one the most common human afflictions, contributing to long-term disability in survivors. Emerging data indicate that functional improvement or deterioration can occur years after TBI. In this regard, TBI is recognized as risk factor for late-life neurodegenerative disorders. TBI encompasses a heterogeneous disease process in which diverse injury subtypes and multiple molecular mechanisms overlap. To develop precision medicine approaches where specific pathobiological processes are targeted by mechanistically appropriate therapies, techniques to identify and measure these subtypes are needed. Traumatic microvascular injury is a common but relatively understudied TBI endophenotype. In this review, we describe evidence of microvascular dysfunction in human and animal TBI, explore the role of vascular dysfunction in neurodegenerative disease, and discuss potential opportunities for vascular-directed therapies in ameliorating TBI-related neurodegeneration. We discuss the therapeutic potential of vascular-directed therapies in TBI and the use and limitations of preclinical models to explore these therapies.
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Affiliation(s)
| | - Asma Bashir
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada; Graduate Program in Neuroscience, University of British Columbia, Vancouver, BC, Canada
| | - Cheryl L Wellington
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada; Djavad Mowafaghian Centre for Brain Health, School of Biomedical Engineering, University of British Columbia, Vancouver, BC, Canada
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Sawosz P, Kacprzak M, Pulawski P, Morawiec M, Bejm K, Bielacz M, Maniewski R, Liebert A, Dabrowski W. Influence of intra-abdominal pressure on the amplitude of fluctuations of cerebral hemoglobin concentration in the respiratory band. BIOMEDICAL OPTICS EXPRESS 2019; 10:3434-3446. [PMID: 31467788 PMCID: PMC6706036 DOI: 10.1364/boe.10.003434] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 05/04/2019] [Accepted: 05/17/2019] [Indexed: 05/15/2023]
Abstract
An intra-abdominal pressure (IAP) is correlated with cerebral perfusion, in a mechanism of reducing venous outflow. The elevated intra-abdominal pressure leads to an increase in the intracranial pressure and a decrease in the cerebral perfusion pressure. We studied the relationship between the IAP and the cerebral oxygenation with the use of the near infrared spectroscopy technique during a gynecological surgery. The changes in hemoglobin concentrations were analyzed in the time-frequency domain in the frequency band related to respiration. The measurements were carried out in 15 subjects who underwent laparoscopic surgery. During the laparoscopy, the intra-abdominal cavity was insufflated with CO2, which caused a controlled increase in the IAP. It was observed that the amplitudes of respiration-related waves present in hemoglobin concentration signals show an increase of 1.5 to 8.5 times during elevation of the IAP by 15 mmHg.
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Affiliation(s)
- Piotr Sawosz
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Warsaw, Poland
| | - Michal Kacprzak
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Warsaw, Poland
| | - Przemyslaw Pulawski
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Warsaw, Poland
| | - Magdalena Morawiec
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Warsaw, Poland
| | - Karolina Bejm
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Warsaw, Poland
| | - Magdalena Bielacz
- Institute of Tourism and Recreation, State Vocational College of Szymon Szymonowicz, Zamosc, Poland
| | - Roman Maniewski
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Warsaw, Poland
| | - Adam Liebert
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Warsaw, Poland
| | - Wojciech Dabrowski
- Department of Anesthesiology and Intensive Therapy, Medical University of Lublin, Lublin, Poland
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Schytz HW, Amin FM, Selb J, Boas DA. Non-invasive methods for measuring vascular changes in neurovascular headaches. J Cereb Blood Flow Metab 2019; 39:633-649. [PMID: 28782410 PMCID: PMC6446419 DOI: 10.1177/0271678x17724138] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Vascular changes during spontaneous headache attacks have been studied over the last 30 years. The interest in cerebral vessels in headache research was initially due to the hypothesis of cerebral vessels as the pain source. Here, we review the knowledge gained by measuring the cerebral vasculature during spontaneous primary headache attacks with the use of single photon emission tomography (SPECT), positron emission tomography (PET), magnetic resonance imaging (MRA) and transcranial Doppler (TCD). Furthermore, the use of near-infrared spectroscopy in headache research is reviewed. Existing TCD studies of migraine and other headache disorders do not provide solid evidence for cerebral blood flow velocity changes during spontaneous attacks of migraine headache. SPECT studies have clearly shown cortical vascular changes following migraine aura and the differences between migraine with aura compared to migraine without aura. PET studies have shown focal activation in brain structures related to headache, but whether the changes are specific to different primary headaches have yet to be demonstrated. MR angiography has shown precise changes in large cerebral vessels during spontaneous migraine without aura attacks. Future development in more precise imaging methods may further elucidate the pathophysiological mechanisms in primary headaches.
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Affiliation(s)
- Henrik W Schytz
- 1 Danish Headache Center and Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark
| | - Faisal M Amin
- 1 Danish Headache Center and Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark
| | - Juliette Selb
- 2 Department of Radiology, MGH/HST Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, USA
| | - David A Boas
- 2 Department of Radiology, MGH/HST Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, USA
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Pham T, Tgavalekos K, Sassaroli A, Blaney G, Fantini S. Quantitative measurements of cerebral blood flow with near-infrared spectroscopy. BIOMEDICAL OPTICS EXPRESS 2019; 10:2117-2134. [PMID: 31061774 PMCID: PMC6484993 DOI: 10.1364/boe.10.002117] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/07/2019] [Accepted: 03/20/2019] [Indexed: 05/29/2023]
Abstract
We propose a new near-infrared spectroscopy (NIRS) method for quantitative measurements of cerebral blood flow (CBF). Because this method uses concepts of coherent hemodynamics spectroscopy (CHS), we identify this new method with the acronym NIRS-CHS. We tested this method on the prefrontal cortex of six healthy human subjects during mean arterial pressure (MAP) transients induced by the rapid deflation of pneumatic thigh cuffs. A comparison of CBF dynamics measured with NIRS-CHS and with diffuse correlation spectroscopy (DCS) showed a good agreement for characteristic times of the CBF transient. We also report absolute measurements of baseline CBF with NIRS-CHS (69 ± 6 ml/100g/min over the six subjects). NIRS-CHS can provide more accurate measurements of CBF with respect to previously reported NIRS surrogates of CBF.
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Affiliation(s)
- Thao Pham
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| | - Kristen Tgavalekos
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| | - Angelo Sassaroli
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| | - Giles Blaney
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| | - Sergio Fantini
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
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Mol A, Woltering JHH, Colier WNJM, Maier AB, Meskers CGM, van Wezel RJA. Sensitivity and reliability of cerebral oxygenation responses to postural changes measured with near-infrared spectroscopy. Eur J Appl Physiol 2019; 119:1117-1125. [PMID: 30771059 PMCID: PMC6469633 DOI: 10.1007/s00421-019-04101-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 02/11/2019] [Indexed: 11/26/2022]
Abstract
Purpose Cerebral oxygenation as measured by near-infrared spectroscopy (NIRS) might be useful to discriminate between physiological and pathological responses after standing up in individuals with orthostatic hypotension. This study addressed the physiological sensitivity of the cerebral oxygenation responses as measured by NIRS to different types and speeds of postural changes in healthy adults and assessed the reliability of these responses. Methods Cerebral oxygenated hemoglobin (O2Hb), deoxygenated hemoglobin (HHb) and tissue saturation index (TSI) were measured bilaterally on the forehead of 15 healthy individuals (12 male, age range 18–27) using NIRS. Participants performed three repeats of sit to stand, and slow and rapid supine to stand movements. Responses were defined as the difference between mean, minimum and maximum O2Hb, HHb and TSI values after standing up and baseline. Test–retest, interobserver and intersensor reliabilities were addressed using intraclass correlation coefficients (ICCs). Results The minimum O2Hb response was most sensitive to postural changes and showed significant differences (− 4.09 µmol/L, p < 0.001) between standing up from sitting and supine position, but not between standing up at different speeds (− 0.31 µmol/L, p = 0.70). The minimum O2Hb response was the most reliable parameter (ICC > 0.6). Conclusions In healthy individuals, NIRS-based cerebral oxygenation parameters are sensitive to postural change and discriminate between standing up from supine and sitting position with minimum O2Hb response as the most sensitive and reliable parameter. The results underpin the potential value for future clinical use of NIRS in individuals with orthostatic hypotension. Electronic supplementary material The online version of this article (10.1007/s00421-019-04101-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Arjen Mol
- Department of Human Movement Sciences, @AgeAmsterdam, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Van der Boechorstraat 9, 1081 BT, Amsterdam, The Netherlands.
- Department of Biophysics, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Heijendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands.
| | - Jeffrey H H Woltering
- Department of Biophysics, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Heijendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | | | - Andrea B Maier
- Department of Human Movement Sciences, @AgeAmsterdam, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Van der Boechorstraat 9, 1081 BT, Amsterdam, The Netherlands
- Department of Medicine and Aged Care, @AgeMelbourne, The Royal Melbourne Hospital, The University of Melbourne, City Campus, Level 6 North, 300 Grattan Street, Parkville, VIC, 3050, Australia
| | - Carel G M Meskers
- Department of Human Movement Sciences, @AgeAmsterdam, Amsterdam Movement Sciences, Vrije Universiteit Amsterdam, Van der Boechorstraat 9, 1081 BT, Amsterdam, The Netherlands
- Department of Rehabilitation Medicine, Amsterdam UMC, Vrije Universiteit, Amsterdam Movement Sciences, P.O. Box 7057, 1007 MB, Amsterdam, The Netherlands
| | - Richard J A van Wezel
- Department of Biophysics, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Heijendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
- Biomedical Signals and Systems, Technical Medical Centre, University of Twente, Zuidhorst Building, P.O. Box 217, 7500 AE, Enschede, The Netherlands
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Tgavalekos K, Pham T, Krishnamurthy N, Sassaroli A, Fantini S. Frequency-resolved analysis of coherent oscillations of local cerebral blood volume, measured with near-infrared spectroscopy, and systemic arterial pressure in healthy human subjects. PLoS One 2019; 14:e0211710. [PMID: 30753203 PMCID: PMC6372153 DOI: 10.1371/journal.pone.0211710] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 01/19/2019] [Indexed: 01/18/2023] Open
Abstract
We report a study on twenty-two healthy human subjects of the dynamic relationship between cerebral hemoglobin concentration ([HbT]), measured with near-infrared spectroscopy (NIRS) in the prefrontal cortex, and systemic arterial blood pressure (ABP), measured with finger plethysmography. [HbT] is a measure of local cerebral blood volume (CBV). We induced hemodynamic oscillations at discrete frequencies in the range 0.04-0.20 Hz with cyclic inflation and deflation of pneumatic cuffs wrapped around the subject's thighs. We modeled the transfer function of ABP and [HbT] in terms of effective arterial (K(a)) and venous (K(v)) compliances, and a cerebral autoregulation time constant (τ(AR)). The mean values (± standard errors) of these parameters across the twenty-two subjects were K(a) = 0.01 ± 0.01 μM/mmHg, K(v) = 0.09 ± 0.05 μM/mmHg, and τ(AR) = 2.2 ± 1.3 s. Spatially resolved measurements in a subset of eight subjects reveal a spatial variability of these parameters that may exceed the inter-subject variability at a set location. This study sheds some light onto the role that ABP and cerebral blood flow (CBF) play in the dynamics of [HbT] measured with NIRS, and paves the way for new non-invasive optical studies of cerebral blood flow and cerebral autoregulation.
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Affiliation(s)
- Kristen Tgavalekos
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts, United States of America
| | - Thao Pham
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts, United States of America
| | - Nishanth Krishnamurthy
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts, United States of America
| | - Angelo Sassaroli
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts, United States of America
| | - Sergio Fantini
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts, United States of America
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Khaksari K, Blaney G, Sassaroli A, Krishnamurthy N, Pham T, Fantini S. Depth dependence of coherent hemodynamics in the human head. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-9. [PMID: 30444084 PMCID: PMC6318717 DOI: 10.1117/1.jbo.23.12.121615] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 10/29/2018] [Indexed: 05/03/2023]
Abstract
We report a near-infrared spectroscopy (NIRS) study of coherent hemodynamic oscillations measured on the human forehead at multiple source-detector distances (1 to 4 cm). The physiological source of the coherent hemodynamics is arterial blood pressure oscillations at a frequency of 0.1 Hz, induced by cyclic inflation (to a pressure of 200 mmHg) and deflation of two thigh cuffs wrapped around the subject's thighs. To interpret our results, we use a recently developed hemodynamic model and a phasor representation of the oscillations of oxyhemoglobin, deoxyhemoglobin, and total hemoglobin concentrations in the tissue (phasors O, D, and T, respectively). The increase in the phase angle between D and O at larger source-detector separations is assigned to greater flow versus volume contributions and to a stronger blood flow autoregulation in deeper tissue (brain cortex) with respect to superficial tissue (scalp and skull). The relatively constant phase lag of T versus arterial blood pressure oscillations at all source-detector distances was assigned to competing effects from stronger autoregulation and smaller arterial-to-venous contributions in deeper tissue with respect to superficial tissue. We demonstrate the application of a hemodynamic model to interpret coherent hemodynamics measured with NIRS and to assess the different nature of shallow (extracerebral) versus deep (cerebral) tissue hemodynamics.
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Affiliation(s)
- Kosar Khaksari
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
| | - Giles Blaney
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
| | - Angelo Sassaroli
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
| | - Nishanth Krishnamurthy
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
| | - Thao Pham
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
| | - Sergio Fantini
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
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Selb J, Wu KC, Sutin J, Lin PY(I, Farzam P, Bechek S, Shenoy A, Patel AB, Boas DA, Franceschini MA, Rosenthal ES. Prolonged monitoring of cerebral blood flow and autoregulation with diffuse correlation spectroscopy in neurocritical care patients. NEUROPHOTONICS 2018; 5:045005. [PMID: 30450363 PMCID: PMC6233866 DOI: 10.1117/1.nph.5.4.045005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 09/24/2018] [Indexed: 05/13/2023]
Abstract
Monitoring of cerebral blood flow (CBF) and autoregulation are essential components of neurocritical care, but continuous noninvasive methods for CBF monitoring are lacking. Diffuse correlation spectroscopy (DCS) is a noninvasive diffuse optical modality that measures a CBF index ( CBF i ) in the cortex microvasculature by monitoring the rapid fluctuations of near-infrared light diffusing through moving red blood cells. We tested the feasibility of monitoring CBF i with DCS in at-risk patients in the Neurosciences Intensive Care Unit. DCS data were acquired continuously for up to 20 h in six patients with aneurysmal subarachnoid hemorrhage, as permitted by clinical care. Mean arterial blood pressure was recorded synchronously, allowing us to derive autoregulation curves and to compute an autoregulation index. The autoregulation curves suggest disrupted cerebral autoregulation in most patients, with the severity of disruption and the limits of preserved autoregulation varying between subjects. Our findings suggest the potential of the DCS modality for noninvasive, long-term monitoring of cerebral perfusion, and autoregulation.
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Affiliation(s)
- Juliette Selb
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Kuan-Cheng Wu
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Jason Sutin
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Pei-Yi (Ivy) Lin
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Parisa Farzam
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Sophia Bechek
- Massachusetts General Hospital, Department of Neurology, Boston, Massachusetts, United States
| | - Apeksha Shenoy
- Massachusetts General Hospital, Department of Neurology, Boston, Massachusetts, United States
| | - Aman B. Patel
- Massachusetts General Hospital, Department of Neurology, Boston, Massachusetts, United States
| | - David A. Boas
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Maria Angela Franceschini
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
- Address all correspondence to: Maria Angela Franceschini, E-mail:
| | - Eric S. Rosenthal
- Massachusetts General Hospital, Department of Neurology, Boston, Massachusetts, United States
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Assessment of cerebral autoregulation using continuous-wave near-infrared spectroscopy during squat-stand maneuvers in subjects with symptoms of orthostatic intolerance. Sci Rep 2018; 8:13257. [PMID: 30185974 PMCID: PMC6125591 DOI: 10.1038/s41598-018-31685-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 08/23/2018] [Indexed: 11/08/2022] Open
Abstract
Orthostatic lightheadedness in healthy young adults often leads to syncope in severe cases. One suggested underlying mechanism of orthostatic lightheadedness is a drop in transient blood pressure (BP); however, a decrease in BP does not always lead to a drop in cerebral blood flow (CBF) due to cerebral autoregulation (CA). We present a direct assessment method of CA using a multichannel continuous-wave near-infrared spectroscopy (CW-NIRS) device that measures the temporal changes in oxy- and deoxy-hemoglobin concentrations in the prefrontal cortex. Twenty healthy young adults were recruited. During the experiment, continuous beat-to-beat BP and heart rate were simultaneously measured during repetitive squat-stand maneuvers. We introduce a new metric termed 'time-derivative hemodynamic model (DHbT)', which is the time-derivative of total-hemoglobin concentration change that reflects the changes of cerebral blood volume and CBF. Although the absolute levels and the variations of systolic and diastolic BPs and mean arterial pressure showed no significant difference between the two groups, the proposed model showed a distinct difference in slope variation and response time of DHbT between the subjects with frequent symptom of orthostatic intolerance and the healthy control subjects. Thus, these results clearly demonstrate the feasibility of using CW-NIRS devices as a CA performance assessment tool.
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Tran NN, Kumar SR, Hodge FS, Macey PM. Cerebral Autoregulation in Neonates With and Without Congenital Heart Disease. Am J Crit Care 2018; 27:410-416. [PMID: 30173174 DOI: 10.4037/ajcc2018672] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Congenital heart disease (CHD) is a leading birth defect in the United States, affecting about 40 000 neonates each year. Despite efforts to prevent developmental delays, many children with CHD have neurological deficits that last into adulthood, influencing employability, self-care, and quality of life. OBJECTIVE To determine if neonates with CHD have impaired cerebral autoregulation and poorer neurodevelopmental outcomes compared with healthy controls. METHODS A total of 44 full-term neonates, 28 with CHD and 16 without, were enrolled in the study. Inclusion criteria included confirmed diagnosis of CHD, stable hemodynamic status, and being no more than 12 days old. Exclusion criteria included intraventricular hemorrhage and intubation. Cerebral autoregulation was determined by measuring regional cerebral oxygenation during a postural change. The Einstein Neonatal Neurobehavioral Assessment Scale was used to measure overall neurodevelopmental outcomes (motor, visual, and auditory functions). RESULTS Of the 28 neonates with CHD, 8 had single-ventricle physiology. A χ2 analysis indicated no significant difference in impaired cerebral autoregulation between neonates with CHD and controls (P = .38). Neonates with CHD had lower regional cerebral oxygenation than did neonates without CHD (P < .001). Regression analyses with adjustments for cerebral autoregulation indicated that neonates with CHD had poorer total neurodevelopmental outcomes scores (β = 9.3; P = .02) and motor scores (β = 7.6; P = .04). CONCLUSION Preoperative neonates with CHD have poorer developmental outcomes and more hypoxemia than do controls.
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Affiliation(s)
- Nhu N. Tran
- Nhu N. Tran is a clinical research nurse III, Department of Cardiothoracic Surgery, Children’s Hospital Los Angeles, Los Angeles, California. Ram Kumar is an assistant professor of surgery, Keck School of Medicine, University of Southern California, Los Angeles, California. Felicia S. Hodge is a professor and Paul M. Macey is an associate professor, School of Nursing, University of California, Los Angeles
| | - S. Ram Kumar
- Nhu N. Tran is a clinical research nurse III, Department of Cardiothoracic Surgery, Children’s Hospital Los Angeles, Los Angeles, California. Ram Kumar is an assistant professor of surgery, Keck School of Medicine, University of Southern California, Los Angeles, California. Felicia S. Hodge is a professor and Paul M. Macey is an associate professor, School of Nursing, University of California, Los Angeles
| | - Felicia S. Hodge
- Nhu N. Tran is a clinical research nurse III, Department of Cardiothoracic Surgery, Children’s Hospital Los Angeles, Los Angeles, California. Ram Kumar is an assistant professor of surgery, Keck School of Medicine, University of Southern California, Los Angeles, California. Felicia S. Hodge is a professor and Paul M. Macey is an associate professor, School of Nursing, University of California, Los Angeles
| | - Paul M. Macey
- Nhu N. Tran is a clinical research nurse III, Department of Cardiothoracic Surgery, Children’s Hospital Los Angeles, Los Angeles, California. Ram Kumar is an assistant professor of surgery, Keck School of Medicine, University of Southern California, Los Angeles, California. Felicia S. Hodge is a professor and Paul M. Macey is an associate professor, School of Nursing, University of California, Los Angeles
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Demir A, Balcı E, Karadeniz Ü. Quick Evaluation of Cerebral Autoregulation Limits with Near Infrared Spectroscopic Techniques in the Intraoperative Period. Turk J Anaesthesiol Reanim 2018; 46:316-318. [PMID: 30140540 DOI: 10.5152/tjar.2018.31697] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Accepted: 04/02/2018] [Indexed: 11/22/2022] Open
Abstract
In this manuscript, we describe a significant advantage of the intraoperative near infrared spectroscopic techniques (NIRS) using in a malignant hypertensive patient during kidney transplantation. This patient underwent operation becasue of the presence of a suitable cadaveric kidney. Moreover, although the patient's hypertension was intensively treated by cardiology for a long time, it could not be controlled. Thus, despite severe hypertension, the patient was anaesthetized. Mean arterial pressures of about 70-90 mmHg, which are considered to be normal for most people, could cause cerebral hypoperfusion in such a patient. It is a significant advantage that the lower limit of cerebral autoregulation is quickly assessed by NIRS in the case of a kidney transplant performed under general anaesthesia.
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Affiliation(s)
- Aslı Demir
- Clinic of Anaesthesiology and Reanimation, Türkiye Yüksek İhtisas Training and Research Hospital, Ankara, Türkiye
| | - Eda Balcı
- Clinic of Anaesthesiology and Reanimation, Türkiye Yüksek İhtisas Training and Research Hospital, Ankara, Türkiye
| | - Ümit Karadeniz
- Clinic of Anaesthesiology and Reanimation, Türkiye Yüksek İhtisas Training and Research Hospital, Ankara, Türkiye
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