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Contini L, Amendola C, Contini D, Torricelli A, Spinelli L, Re R. Detectability of hemodynamic oscillations in cerebral cortex through functional near-infrared spectroscopy: a simulation study. NEUROPHOTONICS 2024; 11:035001. [PMID: 38962430 PMCID: PMC11221108 DOI: 10.1117/1.nph.11.3.035001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 06/05/2024] [Accepted: 06/10/2024] [Indexed: 07/05/2024]
Abstract
Significance We explore the feasibility of using time-domain (TD) and continuous-wave (CW) functional near-infrared spectroscopy (fNIRS) to monitor brain hemodynamic oscillations during resting-state activity in humans, a phenomenon that is of increasing interest in the scientific and medical community and appears to be crucial to advancing the understanding of both healthy and pathological brain functioning. Aim Our general object is to maximize fNIRS sensitivity to brain resting-state oscillations. More specifically, we aim to define comprehensive guidelines for optimizing main operational parameters in fNIRS measurements [average photon count rate, measurement length, sampling frequency, and source-detector distance (SSD)]. In addition, we compare TD and CW fNIRS performance for the detection and localization of oscillations. Approach A series of synthetic TD and CW fNIRS signals were generated by exploiting the solution of the diffusion equation for two different geometries of the probed medium: a homogeneous medium and a bilayer medium. Known and periodical perturbations of the concentrations of oxy- and deoxy-hemoglobin were imposed in the medium, determining changes in its optical properties. The homogeneous slab model was used to determine the effect of multiple measurement parameters on fNIRS sensitivity to oscillatory phenomena, and the bilayer model was used to evaluate and compare the abilities of TD and CW fNIRS in detecting and isolating oscillations occurring at different depths. For TD fNIRS, two approaches to enhance depth-selectivity were evaluated: first, a time-windowing of the photon distribution of time-of-flight was performed, and then, the time-dependent mean partial pathlength (TMPP) method was used to retrieve the hemoglobin concentrations in the medium. Results In the homogeneous medium case, the sensitivity of TD and CW fNIRS to periodical perturbations of the optical properties increases proportionally with the average photon count rate, the measurement length, and the sampling frequency and approximatively with the square of the SSD. In the bilayer medium case, the time-windowing method can detect and correctly localize the presence of oscillatory components in the TD fNIRS signal, even in the presence of very low photon count rates. The TMPP method demonstrates how to correctly retrieve the periodical variation of hemoglobin at different depths from the TD fNIRS signal acquired at a single SSD. For CW fNIRS, measurements taken at typical SSDs used for short-separation channel regression show notable sensitivity to oscillations occurring in the deep layer, challenging the assumptions underlying this correction method when the focus is on analyzing oscillatory phenomena. Conclusions We demonstrated that the TD fNIRS technique allows for the detection and depth-localization of periodical fluctuations of the hemoglobin concentrations within the probed medium using an acquisition at a single SSD, offering an alternative to multi-distance CW fNIRS setups. Moreover, we offered some valuable guidelines that can assist researchers in defining optimal experimental protocols for fNIRS studies.
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Affiliation(s)
| | | | - Davide Contini
- Politecnico di Milano, Dipartimento di Fisica, Milan, Italy
| | - Alessandro Torricelli
- Politecnico di Milano, Dipartimento di Fisica, Milan, Italy
- Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Milan, Italy
| | - Lorenzo Spinelli
- Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Milan, Italy
| | - Rebecca Re
- Politecnico di Milano, Dipartimento di Fisica, Milan, Italy
- Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Milan, Italy
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Schulthess S, Friedl S, Narula G, Brandi G, Willms JF, Keller E, Bicciato G. Low frequency oscillations reflect neurovascular coupling and disappear after cerebral death. Sci Rep 2024; 14:11287. [PMID: 38760449 PMCID: PMC11101423 DOI: 10.1038/s41598-024-61819-4] [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: 01/16/2024] [Accepted: 05/09/2024] [Indexed: 05/19/2024] Open
Abstract
Spectrum power analysis in the low frequency oscillations (LFO) region of functional near infrared spectroscopy (fNIRS) is a promising method to deliver information about brain activation and therefore might be used for prognostication in patients with disorders of consciousness in the neurocritical care unit alongside with established methods. In this study, we measure the cortical hemodynamic response measured by fNIRS in the LFO region following auditory and somatosensory stimulation in healthy subjects. The significant hemodynamic reaction in the contralateral hemisphere correlation with the physiologic electric response suggests neurovascular coupling. In addition, we investigate power spectrum changes in steady state measurements of cerebral death patients and healthy subjects in the LFO region, the frequency of the heartbeat and respiration. The spectral power within the LFO region was lower in the patients with cerebral death compared to the healthy subjects, whereas there were no differences in spectral power for physiological activities such as heartbeat and respiration rate. This finding indicates the cerebral origin of our low frequency measurements. Therefore, LFO measurements are a potential method to detect brain activation in patients with disorders of consciousness and cerebral death. However, further studies in patients are needed to investigate its potential clinical use.
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Affiliation(s)
- Sven Schulthess
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091, Zurich, Switzerland.
| | - Susanne Friedl
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091, Zurich, Switzerland
| | - Gagan Narula
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091, Zurich, Switzerland
| | - Giovanna Brandi
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091, Zurich, Switzerland
| | - Jan Folkard Willms
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091, Zurich, Switzerland
| | - Emanuela Keller
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091, Zurich, Switzerland
| | - Giulio Bicciato
- Department of Neurology, University Hospital Zurich, University of Zurich, 8091, Zurich, Switzerland
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Shu Z, Wu J, Lu J, Li H, Liu J, Lin J, Liang S, Wu J, Han J, Yu N. Effective DBS treatment improves neural information transmission of patients with disorders of consciousness: an fNIRS study. Physiol Meas 2023; 44:125011. [PMID: 38086065 DOI: 10.1088/1361-6579/ad14ab] [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: 06/03/2023] [Accepted: 12/12/2023] [Indexed: 12/30/2023]
Abstract
Objective.Deep brain stimulation (DBS) is a potential treatment that promotes the recovery of patients with disorders of consciousness (DOC). This study quantified the changes in consciousness and the neuromodulation effect of DBS on patients with DOC.Approach.Eleven patients were recruited for this study which consists of three conditions: 'Pre' (two days before DBS surgery), 'Post-On' (one month after surgery with stimulation), and 'Post-Off' (one month after surgery without stimulation). Functional near-infrared spectroscopy (fNIRS) was recorded from the frontal lobe, parietal lobe, and occipital lobe of patients during the experiment of auditory stimuli paradigm, in parallel with the coma recovery scale-revised (CRS-R) assessment. The brain hemodynamic states were defined and state transition acceleration was taken to quantify the information transmission strength of the brain network. Linear regression analysis was conducted between the changes in regional and global indicators and the changes in the CRS-R index.Main results.Significant correlation was observed between the changes in the global transition acceleration indicator and the changes in the CRS-R index (slope = 55.910,p< 0.001,R2= 0.732). For the regional indicators, similar correlations were found between the changes in the frontal lobe and parietal lobe indicators and the changes in the CRS-R index (slope = 46.612,p< 0.01,R2= 0.694; slope = 47.491,p< 0.01,R2= 0.676).Significance.Our study suggests that fNIRS-based brain hemodynamics transition analysis can signify the neuromodulation effect of DBS treatment on patients with DOC, and the transition acceleration indicator is a promising brain functional marker for DOC.
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Affiliation(s)
- Zhilin Shu
- College of Artificial Intelligence, Nankai University, Tianjin 300350, People's Republic of China
- Engineering Research Center of Trusted Behavior Intelligence, Ministry of Education, Nankai University, Tianjin 300350, People's Republic of China
- Institute of Intelligence Technology and Robotic Systems, Shenzhen Research Institute of Nankai University, Shenzhen 518083, People's Republic of China
| | - Jingchao Wu
- Department of Neurosurgery, Tianjin Huanhu Hospital, Tianjin 300350, People's Republic of China
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100050, People's Republic of China
| | - Jiewei Lu
- College of Artificial Intelligence, Nankai University, Tianjin 300350, People's Republic of China
- Engineering Research Center of Trusted Behavior Intelligence, Ministry of Education, Nankai University, Tianjin 300350, People's Republic of China
- Institute of Intelligence Technology and Robotic Systems, Shenzhen Research Institute of Nankai University, Shenzhen 518083, People's Republic of China
| | - Haitao Li
- Department of Neurosurgery, Tianjin Huanhu Hospital, Tianjin 300350, People's Republic of China
| | - Jinrui Liu
- College of Artificial Intelligence, Nankai University, Tianjin 300350, People's Republic of China
- Engineering Research Center of Trusted Behavior Intelligence, Ministry of Education, Nankai University, Tianjin 300350, People's Republic of China
- Institute of Intelligence Technology and Robotic Systems, Shenzhen Research Institute of Nankai University, Shenzhen 518083, People's Republic of China
| | - Jianeng Lin
- College of Artificial Intelligence, Nankai University, Tianjin 300350, People's Republic of China
- Engineering Research Center of Trusted Behavior Intelligence, Ministry of Education, Nankai University, Tianjin 300350, People's Republic of China
- Institute of Intelligence Technology and Robotic Systems, Shenzhen Research Institute of Nankai University, Shenzhen 518083, People's Republic of China
| | - Siquan Liang
- Department of Neurosurgery, Tianjin Huanhu Hospital, Tianjin 300350, People's Republic of China
| | - Jialing Wu
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin 300350, People's Republic of China
- Laboratory of Cerebral Vascular and Neurodegenerative Diseases, Tianjin Neurosurgical Institute, Tianjin Huanhu Hospital, Tianjin 300350, People's Republic of China
| | - Jianda Han
- College of Artificial Intelligence, Nankai University, Tianjin 300350, People's Republic of China
- Engineering Research Center of Trusted Behavior Intelligence, Ministry of Education, Nankai University, Tianjin 300350, People's Republic of China
- Institute of Intelligence Technology and Robotic Systems, Shenzhen Research Institute of Nankai University, Shenzhen 518083, People's Republic of China
| | - Ningbo Yu
- College of Artificial Intelligence, Nankai University, Tianjin 300350, People's Republic of China
- Engineering Research Center of Trusted Behavior Intelligence, Ministry of Education, Nankai University, Tianjin 300350, People's Republic of China
- Institute of Intelligence Technology and Robotic Systems, Shenzhen Research Institute of Nankai University, Shenzhen 518083, People's Republic of China
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Ma Y, Luo K, Ding P, Yin S, Li X, Li Y. Differences in symmetrical low-frequency oscillations among healthy subjects, and those with stroke or peripheral arterial disease. Heliyon 2023; 9:e17015. [PMID: 37484434 PMCID: PMC10361110 DOI: 10.1016/j.heliyon.2023.e17015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 05/30/2023] [Accepted: 06/04/2023] [Indexed: 07/25/2023] Open
Abstract
Low-frequency oscillations (LFOs) observed in near-infrared spectroscopy (NIRS) reflect autonomic physiological processes, and may serve as useful indicators for detecting and monitoring circulatory dysfunction. The aim of this study was to reveal whether LFOs can be used as vascular perfusion biomarkers to differentiate different types and degrees of vascular lesions based on clinical patient data. Materials and Methods: In this study, healthy controls, ischemic stroke patients and peripheral atherosclerosis patients completed a resting-state LFO detection experiment. LFOs were collected simultaneously at peripheral right and left earlobes, fingertips and toes, along with coherence and phase shift analyses processing. Results: The results showed that the coherence coefficients of symmetric peripheral positions and the absolute value-phase shifts of fingers and toes can be used to distinguish healthy individuals, ischemic stroke patients and peripheral atherosclerosis patients. The symmetric earlobes' absolute value-phase shifts could be used to differentiate mild and severe ischemic stroke patients; the coherence coefficients and absolute value-phase shifts of the symmetric toes could be used to differentiate mild and severe peripheral arteriosclerosis patients. The accuracy of differentiating between types of patients was 70%; those with different degrees of peripheral atherosclerosis was 85%, and those with different degrees of ischemic stroke was 72%. Conclusions: LFOs can serve as vascular perfusion biomarkers to differentiate types and degrees of vascular lesions. Therefore, LFOs have the potential to provide valuable patient information to assist researchers and clinicians in identifying specific peripheral circulatory damage subgroups.
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Affiliation(s)
- Yunfei Ma
- School of Information Science and Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, China
| | - Kexin Luo
- School of Information Science and Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, China
| | - Peng Ding
- School of Information Science and Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, China
| | - Shimin Yin
- Department of Neurology, PLA Rocket Force Characteristic Medical Center, Beijing, 100088, China
| | - Xiaoli Li
- Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yingwei Li
- School of Information Science and Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, China
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Bicciato G, Narula G, Brandi G, Eisele A, Schulthess S, Friedl S, Willms JF, Westphal L, Keller E. Functional NIRS to detect covert consciousness in neurocritical patients. Clin Neurophysiol 2022; 144:72-82. [PMID: 36306692 DOI: 10.1016/j.clinph.2022.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 10/01/2022] [Accepted: 10/03/2022] [Indexed: 11/03/2022]
Abstract
OBJECTIVE This pilot study assesses the feasibility to detect covert consciousness in clinically unresponsive patients by means of functional near infrared spectroscopy (fNIRS) in a real intensive care unit setting. We aimed to verify if the hemodynamic response to familiar music measured with fNIRS varies according to the level consciousness of the patients. METHODS 22 neurocritical patients and 6 healthy controls were included. The experiment consisted in 3 subsequent blocks including a first resting state recording, a period of music playback and a second resting state recording. fNIRS measurement were performed on each subject with two optodes on the forehead. Main oscillatory frequencies of oxyhemoglobin signal were analyzed. Spectral changes of low frequency oscillations (LFO) between subsequent experimental blocks were used as a marker of cortical response. Cortical response was compared to the level of consciousness of the patients and their functional outcome, through validated clinical scores. RESULTS Cortical hemodynamic response to music on the left prefrontal brain was associated with the level of consciousness of the patients and with their clinical outcome after three months. CONCLUSIONS Variations in LFO spectral power measured with fNIRS may be a new marker of cortical responsiveness to detect covert consciousness in neurocritical patients. Left prefrontal cortex may play an important role in the perception of familiar music. SIGNIFICANCE We showed the feasibility of a simple fNIRS approach to detect cortical response in the real setting of an intensive care unit.
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Affiliation(s)
- Giulio Bicciato
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091 Zurich, Switzerland; Department of Neurology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland.
| | - Gagan Narula
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091 Zurich, Switzerland
| | - Giovanna Brandi
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091 Zurich, Switzerland
| | - Amanda Eisele
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091 Zurich, Switzerland; Department of Neurology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland
| | - Sven Schulthess
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091 Zurich, Switzerland
| | - Susanne Friedl
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091 Zurich, Switzerland
| | - Jan Folkard Willms
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091 Zurich, Switzerland
| | - Laura Westphal
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091 Zurich, Switzerland; Department of Neurology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland
| | - Emanuela Keller
- Neurocritical Care Unit, Department of Neurosurgery, Institute of Intensive Care Medicine, University Hospital, University of Zurich, 8091 Zurich, Switzerland
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Khaksari K, Smith EG, Miguel HO, Zeytinoglu S, Fox N, Gandjbakhche AH. An fNIRS Study of Brain Lateralization During Observation and Execution of a Fine Motor Task. Front Hum Neurosci 2022; 15:798870. [PMID: 35153703 PMCID: PMC8825352 DOI: 10.3389/fnhum.2021.798870] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 12/28/2021] [Indexed: 11/21/2022] Open
Abstract
Brain activity in the action observation network (AON) is lateralized during action execution, with greater activation in the contralateral hemisphere to the side of the body used to perform the task. However, it is unknown whether the AON is also lateralized when watching another person perform an action. In this study, we use fNIRS to measure brain activity over the left and right cortex while participants completed actions with their left and right hands and watched an actor complete action with their left and right hands. We show that while activation is lateralized when the participants themselves are moving, brain lateralization is not affected by the side of the body when the participant is observing another person's action. In addition, we demonstrate that individual differences in hand preference and dexterity between the right and left hands are related to brain lateralization patterns.
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Affiliation(s)
- Kosar Khaksari
- National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Elizabeth G. Smith
- Department of Behavioral Medicine and Clinical Psychology, Cincinnati Children’s Hospital, Cincinnati, OH, United States
| | - Helga O. Miguel
- National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Selin Zeytinoglu
- Department of Human Development and Quantitative Methodology, University of Maryland, College Park, MD, United States
| | - Nathan Fox
- Department of Human Development and Quantitative Methodology, University of Maryland, College Park, MD, United States
| | - Amir H. Gandjbakhche
- National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
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Basic Examination of Haemoglobin Phase of Oxygenation and Deoxygenation in Resting State and Task Periods in Adults Using fNIRS. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1395:189-198. [PMID: 36527636 DOI: 10.1007/978-3-031-14190-4_32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Functional near-infrared spectroscopy (fNIRS) is a neuroimaging technique used to measure the relative changes in concentrations of oxygenated haemoglobin (oxy-Hb) and deoxygenated haemoglobin (deoxy-Hb) in the cerebral cortex. While most previous studies using fNIRS have relied only on a single oxy-Hb or deoxy-Hb parameter to infer about neural activation, the phase difference between the oxy- and deoxy-Hb signals (haemoglobin phase of oxygenation and deoxygenation: hPod) has been reported to be an important biomarker for analysing haemodynamic characteristics of the brain in infants. In this study, we examined the basic characteristics of adult hPod to develop a new analysis method to detect more sensitive signals that reflect neural activation in adults using fNIRS. We measured the hPod of 12 healthy adults in the frontal and occipital cortex during rest and upon exposure to visual stimuli and the verbal working memory (WM) task. We found that the average hPod values during the entire measurement period ranged between π and 1.5π rad in all conditions. This result indicates that the phase differences in adults were generally close to a stable antiphase pattern (hPod values around π), regardless of the presence or absence of tasks and stimuli. However, when dynamic changes in hPod values were analysed, significant differences between the resting state and WM tasks were observed during activation period in the frontal and occipital regions. These results suggest that the analysis of dynamic hPod change is useful for detecting a subtle activation for cognitive tasks.
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Increase in Low-Frequency Oscillations in fNIRS as Cerebral Response to Auditory Stimulation with Familiar Music. Brain Sci 2021; 12:brainsci12010042. [PMID: 35053789 PMCID: PMC8773668 DOI: 10.3390/brainsci12010042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/16/2021] [Accepted: 12/24/2021] [Indexed: 11/17/2022] Open
Abstract
Recognition of typical patterns of brain response to external stimuli using near-infrared spectroscopy (fNIRS) may become a gateway to detecting covert consciousness in clinically unresponsive patients. This is the first fNIRS study on the cortical hemodynamic response to favorite music using a frequency domain approach. The aim of this study was to identify a possible marker of cognitive response in healthy subjects by investigating variations in the oscillatory signal of fNIRS in the spectral regions of low-frequency (LFO) and very-low-frequency oscillations (VLFO). The experiment consisted of two periods of exposure to preferred music, preceded and followed by a resting phase. Spectral power in the LFO region increased in all the subjects after the first exposure to music and decreased again in the subsequent resting phase. After the second music exposure, the increase in LFO spectral power was less distinct. Changes in LFO spectral power were more after first music exposure and the repetition-related habituation effect strongly suggest a cerebral origin of the fNIRS signal. Recognition of typical patterns of brain response to specific environmental stimulation is a required step for the concrete validation of a fNIRS-based diagnostic tool.
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Liang Z, Tian H, Yang HC, Arimitsu T, Takahashi T, Sassaroli A, Fantini S, Niu H, Minagawa Y, Tong Y. Tracking Brain Development From Neonates to the Elderly by Hemoglobin Phase Measurement Using Functional Near-Infrared Spectroscopy. IEEE J Biomed Health Inform 2021; 25:2497-2509. [PMID: 33493123 DOI: 10.1109/jbhi.2021.3053900] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The biological and neurological processes during the lifespan are dynamic with significant alterations associated with different stages of life. The phase and coupling of oxy-hemoglobin (Δ[HbO]) and deoxy-hemoglobin concentration changes (Δ[Hb]) measured by functional near-infrared spectroscopy (fNIRS) are shown to characterize the neurovascular and metabolic development of infants. However, the changes in phase and coupling across the human lifespan remain mostly unknown. Here, fNIRS measurements of Δ[HbO] and Δ[Hb] conducted at two sites on different age populations (from newborns to elderly) were combined. Firstly, we assessed the influence of random noise on the calculation of the phase difference and phase-locking index (PLI) in fNIRS measurement. The results showed that the phase difference is close to π as the noise intensity approaches -8 dB, and the coupling strength (i.e., PLI) presents a u-shape curve as the noise increase. Secondly, phase difference and PLI in the frequency range 0.01-0.10 Hz were calculated after denoising. It showed that the phase difference increases from newborns to 3-4-month-olds babies. This phase difference persists throughout adulthood until finally being disrupted in the old age. The children's PLI is the highest, followed by that of adults. These two groups' PLI are significantly higher than those of infants and the elderly (p < 0.001). Lastly, a hemodynamic model was used to explain the observations and found close associations with cerebral autoregulation and speed of blood flow. These results demonstrate that the phase-related parameters measured by fNIRS can be used to study the brain and assess brain health throughout the lifespan.
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Vijayakrishnan Nair V, Kish BR, Yang HCS, Yu Z, Guo H, Tong Y, Liang Z. Monitoring anesthesia using simultaneous functional Near Infrared Spectroscopy and Electroencephalography. Clin Neurophysiol 2021; 132:1636-1646. [PMID: 34034088 DOI: 10.1016/j.clinph.2021.03.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 03/02/2021] [Accepted: 03/28/2021] [Indexed: 12/28/2022]
Abstract
OBJECTIVE This study aims to understand the neural and hemodynamic responses during general anesthesia in order to develop a comprehensive multimodal anesthesia depth monitor using simultaneous functional Near Infrared Spectroscopy (fNIRS) and Electroencephalogram (EEG). METHODS 37 adults and 17 children were monitored with simultaneous fNIRS and EEG, during the complete general anesthesia process. The coupling of fNIRS signals with neuronal signals (EEG) was calculated. Measures of complexity (sample entropy) and phase difference were also quantified from fNIRS signals to identify unique fNIRS based biomarkers of general anesthesia. RESULTS A significant decrease in the complexity and power of fNIRS signals characterize the anesthesia maintenance phase. Furthermore, responses to anesthesia vary between adults and children in terms of neurovascular coupling and frontal EEG alpha power. CONCLUSIONS This study shows that fNIRS signals could reliably quantify the underlying neuronal activity under general anesthesia and clearly distinguish the different phases throughout the procedure in adults and children (with less accuracy). SIGNIFICANCE A multimodal approach incorporating the specific differences between age groups, provides a reliable measure of anesthesia depth.
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Affiliation(s)
| | - Brianna R Kish
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States
| | - Ho-Ching Shawn Yang
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States
| | - Zhenyang Yu
- School of Electrical Engineering, Yanshan University, Qinhuangdao, China
| | - Hang Guo
- Department of Anesthesiology, the Seventh Medical Center to Chinese PLA General Hospital, Beijing 100700, China
| | - Yunjie Tong
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States.
| | - Zhenhu Liang
- School of Electrical Engineering, Yanshan University, Qinhuangdao, China
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A Noninvasive Method for Monitoring Intracranial Pressure During Postural Changes. ACTA NEUROCHIRURGICA. SUPPLEMENT 2021. [PMID: 33839832 DOI: 10.1007/978-3-030-59436-7_26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
Intracranial hypertension (IH) is an important cause of secondary brain injury, and its association with poor outcomes has been extensively demonstrated. Pathological intracranial hypertension is defined as a persistent rise in intracranial pressure (ICP) to above 20-25 mmHg, with symptoms such as headaches, loss of consciousness, seizures, and focal deficits, as well as ischemic damage. Therefore, monitoring of ICP is invaluable in the management of these symptoms. However, invasive measurements of ventricular pressure (requiring a surgical procedure) are considered the gold standard, thus limiting the practicality of ICP measurements. Vivonics, Inc., is developing a noninvasive optical device to assess ICP for use by emergency medical personnel, called IPASS: Intracranial Pressure Assessment and Screening System. IPASS uses four near-infrared sensors to measure hemodynamic oscillations at four different locations. Three sensors are used as reference signals and one sensor is used to detect cerebral blood volume oscillations. Pulse arrival delays between the measured cerebral blood volume oscillations and the blood volume oscillations measured at the three reference locations are calculated and correlated with estimated ICP changes, herein modulated by specific positional changes (in a head-down maneuver).
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12
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Ren H, Jiang X, Xu K, Chen C, Yuan Y, Dai C, Chen W. A Review of Cerebral Hemodynamics During Sleep Using Near-Infrared Spectroscopy. Front Neurol 2020; 11:524009. [PMID: 33329295 PMCID: PMC7710901 DOI: 10.3389/fneur.2020.524009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Accepted: 10/26/2020] [Indexed: 11/13/2022] Open
Abstract
Investigating cerebral hemodynamic changes during regular sleep cycles and sleep disorders is fundamental to understanding the nature of physiological and pathological mechanisms in the regulation of cerebral oxygenation during sleep. Although sleep neuroimaging methods have been studied and have been well-reviewed, they have limitations in terms of technique and experimental design. Neurologists are convinced that Near-infrared spectroscopy (NIRS) provides essential information and can be used to assist the assessment of cerebral hemodynamics, and numerous studies regarding sleep have been carried out based on NIRS. Thus, a brief historical overview of the sleep studies using NIRS will be helpful for the biomedical students, academicians, and engineers to better understand NIRS from various perspectives. In this study, the existing literature on sleep studies is reviewed, and an overview of the NIRS applications is synthesized and provided. The paper first reviews the application scenarios, as well as the patterns of fluctuation of NIRS, which includes the investigation in regular sleep and sleep-disordered breathing. Various factors such as different sleep stages, populations, and degrees of severity were considered. Furthermore, the experimental design and signal processing, as well as the regulation mechanisms involved in regular and pathological sleep, are investigated and discussed. The strengths and weaknesses of the existing NIRS applications are addressed and presented, which can direct further NIRS analysis and utilization.
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Affiliation(s)
- Haoran Ren
- The Center for Intelligent Medical Electronics, School of Information Science and Technology, Fudan University, Shanghai, China
| | - Xinyu Jiang
- The Center for Intelligent Medical Electronics, School of Information Science and Technology, Fudan University, Shanghai, China
| | - Ke Xu
- The Center for Intelligent Medical Electronics, School of Information Science and Technology, Fudan University, Shanghai, China
| | - Chen Chen
- The Center for Intelligent Medical Electronics, School of Information Science and Technology, Fudan University, Shanghai, China
| | - Yafei Yuan
- The Center for Intelligent Medical Electronics, School of Information Science and Technology, Fudan University, Shanghai, China
| | - Chenyun Dai
- The Center for Intelligent Medical Electronics, School of Information Science and Technology, Fudan University, Shanghai, China
| | - Wei Chen
- The Center for Intelligent Medical Electronics, School of Information Science and Technology, Fudan University, Shanghai, China.,Human Phenome Institute, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Medical Imaging Computing and Computer Assisted Intervention, Shanghai, China
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13
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Xu M, Zheng Y, Chen X, Li Y, Lin W, Zeng B. Dynamic microcirculation PIPE model for functional neuroimaging, non-neuroimaging, and coherent hemodynamics spectroscopy: blood volume and flow velocity variations, and vascular autoregulation. BIOMEDICAL OPTICS EXPRESS 2020; 11:4602-4626. [PMID: 32923067 PMCID: PMC7449742 DOI: 10.1364/boe.396817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/11/2020] [Accepted: 06/18/2020] [Indexed: 06/11/2023]
Abstract
We present a dynamic microcirculation PIPE model for functional neuroimaging, non-neuroimaging, and coherent hemodynamics spectroscopy. The temporal evolution of the concentration and oxygen saturation of hemoglobin in tissue, comprised of the contributions from the arterioles, capillaries, and venules of microvasculature, is determined by time-resolved hemodynamic and metabolic variations in blood volume, flow velocity, and oxygen consumption with a fluid mechanics treatment. Key parameters regarding microcirculation can be assessed, including the effective blood transit times through the capillaries and the venules, and the rate constant of oxygen release from hemoglobin to tissue. The vascular autoregulation can further be quantified from the relationship between the resolved blood volume and flow velocity variations. The PIPE model shows excellent agreement with the experimental cerebral and cutaneous coherent hemodynamics spectroscopy (CHS) and fMRI-BOLD data. It further identifies the impaired cerebral autoregulation distinctively in hemodialysis patients compared to healthy subjects measured by CHS. This new dynamic microcirculation PIPE model provides a valuable tool for brain and other functional studies with hemodynamic-based techniques. It is instrumental in recovering physiological parameters from analyzing and interpreting the signals measured by hemodynamic-based neuroimaging and non-neuroimaging techniques such as functional near-infrared spectroscopy (fNIRS) and functional magnetic resonance imaging (fMRI) in response to brain activation, physiological challenges, or physical maneuvers.
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Affiliation(s)
- M. Xu
- Institute of Lasers and Biomedical Photonics, Biomedical Engineering College, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
- Dept. of Physics and Astronomy, Hunter College and the Graduate Center, The City University of New York, 695 Park Ave, New York, NY 10065, USA
| | - Yang Zheng
- Institute of Lasers and Biomedical Photonics, Biomedical Engineering College, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Xinlin Chen
- Institute of Lasers and Biomedical Photonics, Biomedical Engineering College, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Ying Li
- Institute of Lasers and Biomedical Photonics, Biomedical Engineering College, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Weihao Lin
- Institute of Lasers and Biomedical Photonics, Biomedical Engineering College, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Bixin Zeng
- Institute of Lasers and Biomedical Photonics, Biomedical Engineering College, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
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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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15
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Effects of Performance and Task Duration on Mental Workload during Working Memory Task. PHOTONICS 2019. [DOI: 10.3390/photonics6030094] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
N-back is a working memory (WM) task to study mental workload on the prefrontal cortex (PFC). We assume that the subject’s performance and changes in mental workload over time depends on the length of the experiment. The performance of the participant can change positively due to the participant’s learning process or negatively because of objective mental fatigue and/or sleepiness. In this pilot study, we examined the PFC activation of 23 healthy subjects while they performed an N-back task with two different levels of task difficulty (2-, and 3-back). The hemodynamic responses were analyzed along with the behavioral data (correct answers). A comparison was done between the hemodynamic activation and behavioral data between the two different task levels and between the beginning and end of the 3-back task. Our results show that there is a significant difference between the two task levels, which is due to the difference in task complication. In addition, a significant difference was seen between the beginning and end of the 3-back task in both behavioral data and hemodynamics due to the subject’s learning process throughout the experiment.
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Blaney G, Sassaroli A, Pham T, Krishnamurthy N, Fantini S. Multi-distance frequency-domain optical measurements of coherent cerebral hemodynamics. PHOTONICS 2019; 6:83. [PMID: 34079837 PMCID: PMC8168742 DOI: 10.3390/photonics6030083] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
We report non-invasive, bilateral optical measurements on the forehead of five healthy human subjects, of 0.1 Hz oscillatory hemodynamics elicited either by cyclic inflation of pneumatic thigh cuffs, or by paced breathing. Optical intensity and the phase of photon-density waves were collected with frequency-domain near-infrared spectroscopy at seven source-detector distances (11-40 mm). Coherent hemodynamic oscillations are represented by phasors of oxyhemoglobin (O) and deoxyhemoglobin (D) concentrations, and by the vector D/O that represents the amplitude ratio and phase difference of D and O. We found that, on average, the amplitude ratio (|D/O|) and the phase difference (∠(D/O)) obtained with single-distance intensity at 11-40 mm increase from 0.1 and -330°, to 0.2 and -200°, respectively. Single-distance phase and the intensity slope featured a weaker dependence on source-detector separation, and yielded |D/O| and ∠(D/O) values of about 0.5 and -200°, respectively, at distances greater than 20 mm. The key findings are: (1) single-distance phase and intensity slope are sensitive to deeper tissue compared to single-distance intensity; (2) deeper tissue hemodynamic oscillations, which more closely represent the brain, feature D and O phasors that are consistent with a greater relative flow-to-volume contributions in brain tissue compared to extracerebral, superficial tissue.
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Affiliation(s)
- Giles Blaney
- Tufts University, Department of Biomedical Engineering
| | | | - Thao Pham
- Tufts University, Department of Biomedical Engineering
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17
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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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18
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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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Fantini S, Frederick B, Sassaroli A. Perspective: Prospects of non-invasive sensing of the human brain with diffuse optical imaging. APL PHOTONICS 2018; 3:110901. [PMID: 31187064 PMCID: PMC6559748 DOI: 10.1063/1.5038571] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 07/14/2018] [Indexed: 05/19/2023]
Abstract
Since the initial demonstration of near-infrared spectroscopy (NIRS) for noninvasive measurements of brain perfusion and metabolism in the 1970s, and its application to functional brain studies (fNIRS) in the 1990s, the field of noninvasive optical studies of the brain has been continuously growing. Technological developments, data analysis advances, and novel areas of application keep advancing the field. In this article, we provide a view of the state of the field of cerebral NIRS, starting with a brief historical introduction and a description of the information content of the NIRS signal. We argue that NIRS and fNIRS studies should always report data of both oxy- and deoxyhemoglobin concentrations in brain tissue, as they complement each other to provide more complete functional and physiological information, and may help identify different types of confounds. One significant challenge is the assessment of absolute tissue properties, be them optical or physiological, so that relative measurements account for the vast majority of NIRS and fNIRS applications. However, even relative measurements of hemodynamics or metabolic changes face the major problem of a potential contamination from extracerebral tissue layers. Accounting for extracerebral contributions to fNIRS signals is one of the most critical barriers in the field. We present some of the approaches that were proposed to tackle this challenge in the study of cerebral hemodynamics and functional connectivity. Finally, we critically compare fNIRS and functional magnetic resonance imaging (fMRI) by relating their measurements in terms of signal and noise, and by commenting on their complementarity.
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Affiliation(s)
- Sergio Fantini
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
| | - Blaise Frederick
- Brain Imaging Center, McLean Hospital, Belmont, MA, USA
- Department of Psychiatry, Harvard University Medical School, Boston, MA, USA
| | - Angelo Sassaroli
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
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Sassaroli A, Tgavalekos K, Fantini S. The meaning of "coherent" and its quantification in coherent hemodynamics spectroscopy. JOURNAL OF INNOVATIVE OPTICAL HEALTH SCIENCES 2018; 11:1850036. [PMID: 31762798 PMCID: PMC6874396 DOI: 10.1142/s1793545818500360] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We have recently introduced a new technique, coherent hemodynamics spectroscopy (CHS), which aims at characterizing a specific kind of tissue hemodynamics that feature a high level of covariation with a given physiological quantity. In this study, we carry out a detailed analysis of the significance of coherence and phase synchronization between oscillations of arterial blood pressure (ABP) and total hemoglobin concentration ([Hbt]), measured with near-infrared spectroscopy (NIRS) during a typical protocol for CHS, based on a cyclic thigh cuff occlusion and release. Even though CHS is based on a linear time invariant model between ABP (input) and NIRS measurands (outputs), for practical reasons in a typical CHS protocol, we induce finite "groups" of ABP oscillations, in which each group is characterized by a different frequency. For this reason, ABP (input) and NIRS measurands (output) are not stationary processes, and we have used wavelet coherence and phase synchronization index (PSI), as a metric of coherence and phase synchronization, respectively. PSI was calculated by using both the wavelet cross spectrum and the Hilbert transform. We have also used linear coherence (which requires stationary process) for comparison with wavelet coherence. The method of surrogate data is used to find critical values for the significance of covariation between ABP and [Hbt]. Because we have found similar critical values for wavelet coherence and PSI by using five of the most used methods of surrogate data, we propose to use the data-independent Gaussian random numbers (GRNs), for CHS. By using wavelet coherence and wavelet cross spectrum, and GRNs as surrogate data, we have found the same results for the significance of coherence and phase synchronization between ABP and [Hbt]: on a total set of 20 periods of cuff oscillations, we have found 17 coherent oscillations and 17 phase synchronous oscillations. Phase synchronization assessed with Hilbert transform yielded similar results with 14 phase synchronous oscillations. Linear coherence and wavelet coherence overall yielded similar number of significant values. We discuss possible reasons for this result. Despite the similarity of linear and wavelet coherence, we argue that wavelet coherence is preferable, especially if one wants to use baseline spontaneous oscillations, in which phase locking and coherence between signals might be only temporary.
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Mukli P, Nagy Z, Racz FS, Herman P, Eke A. Impact of Healthy Aging on Multifractal Hemodynamic Fluctuations in the Human Prefrontal Cortex. Front Physiol 2018; 9:1072. [PMID: 30147657 PMCID: PMC6097581 DOI: 10.3389/fphys.2018.01072] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 07/17/2018] [Indexed: 11/23/2022] Open
Abstract
Fluctuations in resting-state cerebral hemodynamics show scale-free behavior over two distinct scaling ranges. Changes in such bimodal (multi) fractal pattern give insight to altered cerebrovascular or neural function. Our main goal was to assess the distribution of local scale-free properties characterizing cerebral hemodynamics and to disentangle the influence of aging on these multifractal parameters. To this end, we obtained extended resting-state records (N = 214) of oxyhemoglobin (HbO), deoxyhemoglobin (HbR) and total hemoglobin (HbT) concentration time series with continuous-wave near-infrared spectroscopy technology from the brain cortex. 52 healthy volunteers were enrolled in this study: 24 young (30.6 ± 8.2 years), and 28 elderly (60.5 ± 12.0 years) subjects. Using screening tests on power-law, multifractal noise, and shuffled data sets we evaluated the presence of true multifractal hemodynamics reflecting long-range correlation (LRC). Subsequently, scaling-range adaptive bimodal signal summation conversion (SSC) was performed based on standard deviation (σ) of signal windows across a range of temporal scales (s). Building on moments of different order (q) of the measure, σ(s), multifractal SSC yielded generalized Hurst exponent function, H(q), and singularity spectrum, D(h) separately for a fast and slow component (the latter dominating the highest temporal scales). Parameters were calculated reflecting the estimated measure at s = N (focus), degree of LRC [Hurst exponent, H(2) and maximal Hölder exponent, hmax] and measuring strength of multifractality [full-width-half-maximum of D(h) and ΔH15 = H(−15)−H(15)]. Correlation-based signal improvement (CBSI) enhanced our signal in terms of interpreting changes due to neural activity or local/systemic hemodynamic influences. We characterized the HbO-HbR relationship with the aid of fractal scale-wise correlation coefficient, rσ(s) and SSC-based multifractal covariance analysis. In the majority of subjects, cerebral hemodynamic fluctuations proved bimodal multifractal. In case of slow component of raw HbT, hmax, and Ĥ(2) were lower in the young group explained by a significantly increased rσ(s) among elderly at high temporal scales. Regarding the fast component of CBSI-pretreated HbT and that of HbO-HbR covariance, hmax, and focus were decreased in the elderly group. These observations suggest an attenuation of neurovascular coupling reflected by a decreased autocorrelation of the neuronal component concomitant with an accompanying increased autocorrelation of the non-neuronal component in the elderly group.
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Affiliation(s)
- Peter Mukli
- Institute of Clinical Experimental Research, Semmelweis University, Budapest, Hungary.,Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Zoltan Nagy
- Institute of Clinical Experimental Research, Semmelweis University, Budapest, Hungary
| | - Frigyes S Racz
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Peter Herman
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, United States
| | - Andras Eke
- Institute of Clinical Experimental Research, Semmelweis University, Budapest, Hungary.,Department of Physiology, Semmelweis University, Budapest, Hungary
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Taga G, Watanabe H, Homae F. Spatial variation in the hemoglobin phase of oxygenation and deoxygenation in the developing cortex of infants. NEUROPHOTONICS 2018; 5:011017. [PMID: 29021987 PMCID: PMC5633865 DOI: 10.1117/1.nph.5.1.011017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 09/18/2017] [Indexed: 05/06/2023]
Abstract
Spontaneous low-frequency oscillatory changes in oxygenated hemoglobin (oxy-Hb) and deoxygenated hemoglobin (deoxy-Hb) are observed using functional near-infrared spectroscopy (fNIRS). A previous study showed that the time-averaged phase difference between oxy-Hb and deoxy-Hb changes, referred to as hemoglobin phase of oxygenation and deoxygenation (hPod), is sensitive to the development of the cortex. We examined phase-locking index of hPod, referred to as [Formula: see text], in addition to hPod, in neonates and 3- and 6-month-old infants using the 94-channel fNIRS data, which covered large lateral regions of the cortex. The results showed that (1) developmental changes in hPod exhibited spatial dependency; (2) [Formula: see text] increased between the neonate group and 3-month-old infant group over the posterior, but not anterior, regions of the cortex; and (3) the cortical regions of each age group were clustered in several domains with specific characteristics of hPod and [Formula: see text]. This study indicates that the neonatal cortex is composed of regions with specific characteristics of hPod and [Formula: see text], and drastic changes occur between the neonatal period and 3 months of age. This study suggests that hPod and [Formula: see text] are sensitive to the cortical region-specific development of the circulatory, blood flow, metabolic, and neurovascular functions in young infants.
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Affiliation(s)
- Gentaro Taga
- The University of Tokyo, Graduate School of Education, Tokyo, Japan
- Address all correspondence to: Gentaro Taga, E-mail:
| | - Hama Watanabe
- The University of Tokyo, Graduate School of Education, Tokyo, Japan
| | - Fumitaka Homae
- Tokyo Metropolitan University, Department of Language Sciences, Hachioji-shi, Tokyo, Japan
- Tokyo Metropolitan University, Research Center for Language, Brain and Genetics, Hachioji-shi, Tokyo, Japan
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23
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Chiarelli AM, Zappasodi F, Di Pompeo F, Merla A. Simultaneous functional near-infrared spectroscopy and electroencephalography for monitoring of human brain activity and oxygenation: a review. NEUROPHOTONICS 2017; 4:041411. [PMID: 28840162 PMCID: PMC5566595 DOI: 10.1117/1.nph.4.4.041411] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 07/24/2017] [Indexed: 05/24/2023]
Abstract
Multimodal monitoring has become particularly common in the study of human brain function. In this context, combined, synchronous measurements of functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG) are getting increased interest. Because of the absence of electro-optical interference, it is quite simple to integrate these two noninvasive recording procedures of brain activity. fNIRS and EEG are both scalp-located procedures. fNIRS estimates brain hemodynamic fluctuations relying on spectroscopic measurements, whereas EEG captures the macroscopic temporal dynamics of brain electrical activity through passive voltages evaluations. The "orthogonal" neurophysiological information provided by the two technologies and the increasing interest in the neurovascular coupling phenomenon further encourage their integration. This review provides, together with an introduction regarding the principles and future directions of the two technologies, an evaluation of major clinical and nonclinical applications of this flexible, low-cost combination of neuroimaging modalities. fNIRS-EEG systems exploit the ability of the two technologies to be conducted in an environment or experimental setting and/or on subjects that are generally not suited for other neuroimaging modalities, such as functional magnetic resonance imaging, positron emission tomography, and magnetoencephalography. fNIRS-EEG brain monitoring settles itself as a useful multimodal tool for brain electrical and hemodynamic activity investigation.
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Affiliation(s)
- Antonio M. Chiarelli
- University of Illinois at Urbana Champaign, Beckman Institute, Urbana, Illinois, United States
| | - Filippo Zappasodi
- Università G. d’Annunzio, Department of Neuroscience, Imaging and Clinical Science, Chieti, Italy
- Università G. d’Annunzio, Institute for Advanced Biomedical Technologies, Chieti, Italy
| | - Francesco Di Pompeo
- Università G. d’Annunzio, Department of Neuroscience, Imaging and Clinical Science, Chieti, Italy
- Università G. d’Annunzio, Institute for Advanced Biomedical Technologies, Chieti, Italy
| | - Arcangelo Merla
- Università G. d’Annunzio, Department of Neuroscience, Imaging and Clinical Science, Chieti, Italy
- Università G. d’Annunzio, Institute for Advanced Biomedical Technologies, Chieti, Italy
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Tgavalekos KT, Kainerstorfer JM, Sassaroli A, Fantini S. Blood-pressure-induced oscillations of deoxy- and oxyhemoglobin concentrations are in-phase in the healthy breast and out-of-phase in the healthy brain. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:101410. [PMID: 27020418 PMCID: PMC4809098 DOI: 10.1117/1.jbo.21.10.101410] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 03/03/2016] [Indexed: 05/29/2023]
Abstract
We present a near-infrared spectroscopy (NIRS) study of local hemodynamics in the breast and the brain (prefrontal cortex) of healthy volunteers in a protocol involving periodic perturbations to the systemic arterial blood pressure. These periodic perturbations were achieved by cyclic inflation (to a pressure of 200 mmHg) and deflation (at frequencies of 0.046, 0.056, 0.063, 0.071, and 0.083 Hz) of two pneumatic cuffs wrapped around the subject’s thighs. As a result of these systemic perturbations, the concentrations of deoxy- and oxyhemoglobin in tissue (D and O , respectively) oscillate at the set frequency. We found that the oscillations of D and O in breast tissue are in-phase at all frequencies considered, a result that we attribute to dominant contributions from blood volume oscillations. In contrast, D and O oscillations in brain tissue feature a frequency-dependent phase difference, which we attribute to significant contributions from cerebral blood flow oscillations. Frequency-resolved measurements of D and O oscillations are exploited by the technique of coherent hemodynamics spectroscopy for the assessment of cerebrovascular parameters and cerebral autoregulation. We show the relevant physiological information content of NIRS measurements of oscillatory hemodynamics, which have qualitatively distinct features in the healthy breast and healthy brain.
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Affiliation(s)
- Kristen T. Tgavalekos
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, Massachusetts 02155, United States
| | - Jana M. Kainerstorfer
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, Massachusetts 02155, United States
| | - Angelo Sassaroli
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, Massachusetts 02155, United States
| | - Sergio Fantini
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, Massachusetts 02155, United States
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25
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Zhang Z, Schneider M, Laures M, Qi M, Khatami R. The Comparisons of Cerebral Hemodynamics Induced by Obstructive Sleep Apnea with Arousal and Periodic Limb Movement with Arousal: A Pilot NIRS Study. Front Neurosci 2016; 10:403. [PMID: 27630539 PMCID: PMC5005379 DOI: 10.3389/fnins.2016.00403] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 08/18/2016] [Indexed: 11/13/2022] Open
Abstract
Obstructive sleep apnea syndrome (OSA) and restless legs syndrome (RLS) with periodic limb movement during sleep (PLMS) are two sleep disorders characterized by repetitive respiratory or movement events associated with cortical arousals. We compared the cerebral hemodynamic changes linked to periodic apneas/hypopneas with arousals (AHA) in four OSA-patients with periodic limb movements (PLMA) with arousals in four patients with RLS-PLMS using near-infrared spectroscopy (NIRS). AHA induced homogenous pattern of periodic fluctuations in oxygenated (HbO2) and deoxygenated (HHb) hemoglobin, i.e., the decrease of HbO2 was accompanied by an increase of HHb during the respiratory event and resolved to reverse pattern when cortical arousal started. Blood volume (BV) showed the same pattern as HHb but with relative smaller amplitude in most of the AHA events.These changing patterns were significant as Wilcoxon signed-rank tests gave p < 0.001 when comparing the area under the curve of these hemodynamic parameters to zero. By contrast, in PLMA limb movements induced periodic increments in HbO2 and BV (Wilcoxon signed-rank tests, p < 0.001), but HHb changed more heterogeneously even during the events coming from the same patient. Heart rate (HR) also showed different patterns between AHA and PLMA. It significantly decreased during the respiratory event (Wilcoxon signed-rank test, p < 0.001) and then increased after the occurrence of cortical arousal (Wilcoxon signed-rank test, p < 0.001); while in PLMA HR first increased preceding the occurrence of cortical arousal (Wilcoxon signed-rank test, p < 0.001) and then decreased. The results of this preliminary study show that both AHA and PLMA induce changes in cerebral hemodynamics. The occurrence of cortical arousal is accompanied by increased HR in both events, but by different BV changes (i.e., decreased/increased BV in AHA/PLMA, respectively). HR changes may partially account for the increased cerebral hemodynamics during PLMA; whereas in AHA probable vasodilatation mediated by hypoxia/hypercapnia is more crucial for the post-arousal hemodynamics. The differences between changes of cerebral hemodynamics and HR may indicate different pathological mechanisms behind these two sleep disorder events.
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Affiliation(s)
- Zhongxing Zhang
- Center for Sleep Medicine and Sleep Research, Clinic BarmelweidBarmelweid, Switzerland
- Bern Network for Epilepsy, Sleep and Consciousness (BENESCO), Department of Neurology, University Hospital Bern, University of BernBern, Switzerland
| | - Maja Schneider
- Center for Sleep Medicine and Sleep Research, Clinic BarmelweidBarmelweid, Switzerland
| | - Marco Laures
- Center for Sleep Medicine and Sleep Research, Clinic BarmelweidBarmelweid, Switzerland
| | - Ming Qi
- Center for Sleep Medicine and Sleep Research, Clinic BarmelweidBarmelweid, Switzerland
| | - Ramin Khatami
- Center for Sleep Medicine and Sleep Research, Clinic BarmelweidBarmelweid, Switzerland
- Bern Network for Epilepsy, Sleep and Consciousness (BENESCO), Department of Neurology, University Hospital Bern, University of BernBern, Switzerland
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Oldag A, Neumann J, Goertler M, Hinrichs H, Heinze HJ, Kupsch A, Sweeney-Reed CM, Kopitzki K. Near-infrared spectroscopy and transcranial sonography to evaluate cerebral autoregulation in middle cerebral artery steno-occlusive disease. J Neurol 2016; 263:2296-2301. [PMID: 27544503 DOI: 10.1007/s00415-016-8262-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 08/06/2016] [Accepted: 08/08/2016] [Indexed: 10/21/2022]
Abstract
The measurement of autoregulatory delay by near-infrared spectroscopy (NIRS) has been proposed as an alternative technique to assess cerebral autoregulation, which is routinely assessed via transcranial Doppler sonography (TCD) in most centers. Comparitive studies of NIRS and TCD, however, are largely missing. We investigated whether cerebrovascular reserve (CVR), as assessed via TCD, correlates with the delay of the autoregulatory response to changes in arterial blood pressure (ABP) as assessed by NIRS, i.e., if impaired upstream vasomotor reactivity is reflected by downstream cortical autoregulation. Twenty patients with unilateral high-grade steno-occlusion of the middle cerebral artery (MCA) underwent bilateral multichannel NIRS of the cortical MCA distributions over a period of 6 min while breathing at a constant rate of 6 cycles/min to induce stable oscillations in ABP. The phase shift φ between ABP and cortical blood oxygenation was calculated as a measure of autoregulatory latency. In a subgroup of 13 patients, CO2 reactivity of the MCAs was determined by TCD to assess CVR in terms of normalized autoregulatory response (NAR). Mean phase shift between ABP and blood oxygenation was significantly increased over the hemisphere ipsilateral to the steno-occlusion (n = 20, p = 0.042). The interhemispheric difference Δφ in phase shift was significantly larger in patients with markedly diminished or exhausted CVR (NAR < 10) than in patients with normal NAR values (NAR ≥ 10) (p = 0.007). Within the MCA core distribution territory, a strong correlation existed between Δφ and CO2 reactivity of the affected MCA (n = 13, r = -0.78, p = 0.011). NIRS may provide an alternative or supplementary approach to evaluate cerebral autoregulation in risk assessment of ischemic events in steno-occlusive disease of cerebral arteries, especially in patients with insufficient bone windows for TCD.
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Affiliation(s)
- Andreas Oldag
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Jens Neumann
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Michael Goertler
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany.,Leibniz Institute for Neurobiology, Brenneckestrasse 6, 39118, Magdeburg, Germany
| | - Hermann Hinrichs
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany.,Leibniz Institute for Neurobiology, Brenneckestrasse 6, 39118, Magdeburg, Germany
| | - Hans-Jochen Heinze
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany.,Leibniz Institute for Neurobiology, Brenneckestrasse 6, 39118, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Andreas Kupsch
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Catherine M Sweeney-Reed
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Klaus Kopitzki
- Clinic for Neurology and Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Strasse 44, 39120, Magdeburg, Germany. .,Leibniz Institute for Neurobiology, Brenneckestrasse 6, 39118, Magdeburg, Germany.
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Diffuse optical spectroscopic imaging of subcutaneous adipose tissue metabolic changes during weight loss. Int J Obes (Lond) 2016; 40:1292-300. [PMID: 27089996 PMCID: PMC4970874 DOI: 10.1038/ijo.2016.43] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 01/26/2016] [Accepted: 03/04/2016] [Indexed: 02/06/2023]
Abstract
Background Changes in subcutaneous adipose tissue (AT) structure and metabolism have been shown to correlate with the development of obesity and related metabolic disorders. Measurements of AT physiology could provide new insight into metabolic disease progression and response to therapy. An emerging functional imaging technology, Diffuse Optical Spectroscopic Imaging (DOSI), was used to obtain quantitative measures of near infrared (NIR) AT optical and physiological properties. Methods 10 overweight or obese adults were assessed during three-months on calorie-restricted diets. DOSI-derived tissue concentrations of hemoglobin, water, and lipid and the wavelength-dependent scattering amplitude (A) and slope (b) obtained from 30 abdominal locations and three time points (T0, T6, T12) were calculated and analyzed using linear mixed effects models, and were also used to form 3D surface images. Results Subjects lost a mean of 11.7 ± 3.4% of starting weight, while significant changes in A (+0.23 ± 0.04 mm−1, adj. p < 0.001), b (−0.17 ± 0.04, adj. p < 0.001), tissue water fraction (+7.2 ± 1.1%, adj. p < 0.001) and deoxyhemoglobin [HbR] (1.1 ± 0.3 µM, adj. p < 0.001) were observed using mixed effect model analysis. Discussion Optical scattering signals reveal alterations in tissue structure which possibly correlate with reductions in adipose cell volume, while water and hemoglobin dynamics suggest improved AT perfusion and oxygen extraction. These results suggest that DOSI measurements of NIR optical and physiological properties could be used to enhance understanding of the role of AT in metabolic disorders and provide new strategies for diagnostic monitoring of obesity and weight loss.
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Byun JI, Jung KY, Lee GT, Kim CK, Kim BM. Spontaneous Low-Frequency Cerebral Hemodynamics Oscillations in Restless Legs Syndrome with Periodic Limb Movements During Sleep: A Near-Infrared Spectroscopy Study. J Clin Neurol 2016; 12:107-14. [PMID: 26754783 PMCID: PMC4712275 DOI: 10.3988/jcn.2016.12.1.107] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 07/20/2015] [Accepted: 07/21/2015] [Indexed: 11/24/2022] Open
Abstract
Background and Purpose Periodic limb movements (PLM) during sleep (PLMS) are associated with cortical and cardiovascular activation. Changes in cerebral hemodynamics caused by cortical activity can be measured using near-infrared spectroscopy (NIRS). We investigated oscillatory components of cerebral hemodynamics during PLM and different sleep stages in restless legs syndrome (RLS) patients with PLMS. Methods Four female RLS patients with PLMS, and four age- and sex-matched normal controls were included. PLM and sleep stages were scored using polysomnography, while the spontaneous cerebral hemodynamics was measured by NIRS. The phase and amplitude of the cerebral oxyhemoglobin concentration [HbO] and the deoxyhemoglobin concentration [Hb] low-frequency oscillations (LFOs) were evaluated during each sleep stage [waking, light sleep (LS; stages N1 and N2), slow-wave sleep (stage N3), and rapid eye movement (REM) sleep]. In RLS patients with PLMS, the cerebral hemodynamics during LS was divided into LS with and without PLM. Results The cerebral hemodynamics activity varied among the different sleep stages. There were changes in phase differences between [HbO] and [Hb] LFOs during the different sleep stages in the normal controls but not in the RLS patients with PLMS. The [HbO] and [Hb] LFO amplitudes were higher in the patient group than in controls during both LS with PLM and REM sleep. Conclusions The present study has demonstrated the presence of cerebral hemodynamics disturbances in RLS patients with PLMS, which may contribute to an increased risk of cerebrovascular events.
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Affiliation(s)
- Jung Ick Byun
- Department of Neurology, Seoul National University Hospital, Seoul, Korea
| | - Ki Young Jung
- Department of Neurology, Seoul National University Hospital, Seoul, Korea.,Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, Korea.
| | - Gwan Taek Lee
- Department of Neurology, College of Medicine, Korea University, Seoul, Korea
| | - Choong Ki Kim
- Department of Biomedical Engineering, Korea University, Seoul, Korea
| | - Beop Min Kim
- Department of Biomedical Engineering, Korea University, Seoul, Korea.
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29
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Fukuda Y, Ida Y, Matsumoto T, Takemura N, Sakatani K. A Bayesian Algorithm for Anxiety Index Prediction Based on Cerebral Blood Oxygenation in the Prefrontal Cortex Measured by Near Infrared Spectroscopy. IEEE JOURNAL OF TRANSLATIONAL ENGINEERING IN HEALTH AND MEDICINE-JTEHM 2014; 2:2200110. [PMID: 27170880 PMCID: PMC4848070 DOI: 10.1109/jtehm.2014.2361757] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 08/16/2014] [Accepted: 09/18/2014] [Indexed: 11/09/2022]
Abstract
Stress-induced psychological and somatic diseases are virtually endemic nowadays. Written self-report anxiety measures are available; however, these indices tend to be time consuming to acquire. For medical patients, completing written reports can be burdensome if they are weak, in pain, or in acute anxiety states. Consequently, simple and fast non-invasive methods for assessing stress response from neurophysiological data are essential. In this paper, we report on a study that makes predictions of the state-trait anxiety inventory (STAI) index from oxyhemoglobin and deoxyhemoglobin concentration changes of the prefrontal cortex using a two-channel portable near-infrared spectroscopy device. Predictions are achieved by constructing machine learning algorithms within a Bayesian framework with nonlinear basis function together with Markov Chain Monte Carlo implementation. In this paper, prediction experiments were performed against four different data sets, i.e., two comprising young subjects, and the remaining two comprising elderly subjects. The number of subjects in each data set varied between 17 and 20 and each subject participated only once. They were not asked to perform any task; instead, they were at rest. The root mean square errors for the four groups were 6.20, 6.62, 4.50, and 6.38, respectively. There appeared to be no significant distinctions of prediction accuracies between age groups and since the STAI are defined between 20 and 80, the predictions appeared reasonably accurate. The results indicate potential applications to practical situations such as stress management and medical practice.
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30
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Zhang Z, Khatami R. Predominant endothelial vasomotor activity during human sleep: a near-infrared spectroscopy study. Eur J Neurosci 2014; 40:3396-404. [DOI: 10.1111/ejn.12702] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 07/24/2014] [Accepted: 07/29/2014] [Indexed: 10/24/2022]
Affiliation(s)
- Zhongxing Zhang
- Center for Sleep Medicine and Sleep Research; Clinic Barmelweid; 5017 Barmelweid Switzerland
- Department of Neurology; University Hospital Zurich; Zurich Switzerland
| | - Ramin Khatami
- Center for Sleep Medicine and Sleep Research; Clinic Barmelweid; 5017 Barmelweid Switzerland
- Department of Neurology; University Hospital Zurich; Zurich Switzerland
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31
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Zhang Q, Ivkovic V, Hu G, Strangman GE. Twenty-four-hour ambulatory recording of cerebral hemodynamics, systemic hemodynamics, electrocardiography, and actigraphy during people's daily activities. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:47003. [PMID: 24781591 DOI: 10.1117/1.jbo.19.4.047003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 03/05/2014] [Indexed: 06/03/2023]
Abstract
The feasibility and utility of wearable 24-h multimodality neuromonitoring during daily activities are demonstrated. We have developed a fourth-generation ambulatory near infrared spectroscopy device, namely NINscan 4. NINscan 4 enables recording of brain function (via cerebral hemodynamics), systemic hemodynamics, electrocardiography, and actigraphy simultaneously and continuously for up to 24 h at 250-Hz sampling rate, during (and with minor restriction to) daily activities. We present initial 24-h human subject test results, with example analysis including (1) comparison of cerebral perfusion and oxygenation changes during wakefulness and sleep over a 24-h period and (2) capturing of hemodynamic changes prior, during and after sudden waken up in the night during sleep. These results demonstrate the first ambulatory 24-h cerebral and systemic hemodynamics monitoring, and its unique advantages including long-term data collection and analysis capability, ability to catch unpredictable transient events during activities of daily living, as well as coregistered multimodality analysis capabilities. These results also demonstrate that NINscan 4's motion artifact at 1-g head movement is smaller than physiological hemodynamic fluctuations during motionless sleep. The broader potential of this technology is also discussed.
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Affiliation(s)
- Quan Zhang
- Massachusetts General Hospital, Harvard Medical School Neural Systems Group, 13th Street, Building 149, Room 2651, Charlestown, Massachusetts 02129bCenter for Space Medicine, Baylor College of Medicine, Houston, Texas
| | - Vladimir Ivkovic
- Massachusetts General Hospital, Harvard Medical School Neural Systems Group, 13th Street, Building 149, Room 2651, Charlestown, Massachusetts 02129
| | - Gang Hu
- Massachusetts General Hospital, Harvard Medical School Neural Systems Group, 13th Street, Building 149, Room 2651, Charlestown, Massachusetts 02129
| | - Gary E Strangman
- Massachusetts General Hospital, Harvard Medical School Neural Systems Group, 13th Street, Building 149, Room 2651, Charlestown, Massachusetts 02129bCenter for Space Medicine, Baylor College of Medicine, Houston, Texas
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32
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Pierro ML, Kainerstorfer JM, Civiletto A, Weiner DE, Sassaroli A, Hallacoglu B, Fantini S. Reduced speed of microvascular blood flow in hemodialysis patients versus healthy controls: a coherent hemodynamics spectroscopy study. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:026005. [PMID: 24522805 PMCID: PMC3922146 DOI: 10.1117/1.jbo.19.2.026005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 01/08/2014] [Accepted: 01/10/2014] [Indexed: 05/19/2023]
Abstract
We present a pilot clinical application of coherent hemodynamics spectroscopy (CHS), a technique to investigate cerebral hemodynamics at the microcirculatory level. CHS relies on frequency-resolved measurements of induced cerebral hemodynamic oscillations that are measured with near-infrared spectroscopy (NIRS) and analyzed with a hemodynamic model. We have used cyclic inflation (200 mmHg) and deflation of a pneumatic cuff placed around the subject's thigh at seven frequencies in the range of 0.03 to 0.17 Hz to generate CHS spectra and to obtain a set of physiological parameters that include the blood transit times in the cerebral microcirculation, the cutoff frequency for cerebral autoregulation, and blood volume ratios across the three different compartments. We have investigated five hemodialysis patients, during the hemodialysis procedure, and six healthy subjects. We have found that the blood transit time in the cerebral microcirculation is significantly longer in hemodialysis patients with respect to healthy subjects. No significant differences were observed between the two groups in terms of autoregulation efficiency and blood volume ratios. The demonstration of the applicability of CHS in a clinical setting and its sensitivity to the highly important cerebral microcirculation may open up new opportunities for NIRS applications in research and in medical diagnostics and monitoring.
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Affiliation(s)
- Michele L. Pierro
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, Massachusetts 02155
| | - Jana M. Kainerstorfer
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, Massachusetts 02155
- Address all correspondence to: Jana M. Kainerstorfer, E-mail:
| | - Amanda Civiletto
- Tufts Medical Center, 800 Washington Street, Boston, Massachusetts 02111
| | - Daniel E. Weiner
- Tufts Medical Center, 800 Washington Street, Boston, Massachusetts 02111
| | - Angelo Sassaroli
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, Massachusetts 02155
| | - Bertan Hallacoglu
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, Massachusetts 02155
| | - Sergio Fantini
- Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, Massachusetts 02155
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Nakao T, Matsumoto T, Shimizu D, Morita M, Yoshimura S, Northoff G, Morinobu S, Okamoto Y, Yamawaki S. Resting state low-frequency fluctuations in prefrontal cortex reflect degrees of harm avoidance and novelty seeking: an exploratory NIRS study. Front Syst Neurosci 2013; 7:115. [PMID: 24381545 PMCID: PMC3865766 DOI: 10.3389/fnsys.2013.00115] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 12/02/2013] [Indexed: 12/14/2022] Open
Abstract
Harm avoidance (HA) and novelty seeking (NS) are temperament dimensions defined by Temperament and Character Inventory (TCI), respectively, reflecting a heritable bias for intense response to aversive stimuli or for excitement in response to novel stimuli. High HA is regarded as a risk factor for major depressive disorder and anxiety disorder. In contrast, higher NS is linked to increased risk for substance abuse and pathological gambling disorder. A growing body of evidence suggests that patients with these disorders show abnormality in the power of slow oscillations of resting-state brain activity. It is particularly interesting that previous studies have demonstrated that resting state activities in medial prefrontal cortex (MPFC) are associated with HA or NS scores, although the relation between the power of resting state slow oscillations and these temperament dimensions remains poorly elucidated. This preliminary study investigated the biological bases of these temperament traits by particularly addressing the resting state low-frequency fluctuations in MPFC. Regional hemodynamic changes in channels covering MPFC during 5-min resting states were measured from 22 healthy participants using near-infrared spectroscopy (NIRS). These data were used for correlation analyses. Results show that the power of slow oscillations during resting state around the dorsal part of MPFC is negatively correlated with the HA score. In contrast, NS was positively correlated with the power of resting state slow oscillations around the ventral part of MPFC. These results suggest that the powers of slow oscillation at rest in dorsal or ventral MPFC, respectively, reflect the degrees of HA and NS. This exploratory study therefore uncovers novel neural bases of HA and NS. We discuss a neural mechanism underlying aversion-related and reward-related processing based on results obtained from this study.
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Affiliation(s)
- Takashi Nakao
- Department of Psychology, Graduate School of Education, Hiroshima University Hiroshima, Japan
| | - Tomoya Matsumoto
- Department of Psychiatry and Neurosciences, Institute of Biomedical and Health Sciences, Hiroshima University Hiroshima, Japan
| | | | - Machiko Morita
- Faculty of Medicine, Hiroshima University Hiroshima, Japan
| | - Shinpei Yoshimura
- Department of Psychology, Faculty of Psychology, Otemon Gakuin University Osaka, Japan
| | - Georg Northoff
- Institute of Mental Health Research, University of Ottawa Ottawa, ON, Canada
| | - Shigeru Morinobu
- Department of Psychiatry and Neurosciences, Institute of Biomedical and Health Sciences, Hiroshima University Hiroshima, Japan ; Department of Neuropsychiatry, Kochi University Kochi, Japan
| | - Yasumasa Okamoto
- Department of Psychiatry and Neurosciences, Institute of Biomedical and Health Sciences, Hiroshima University Hiroshima, Japan
| | - Shigeto Yamawaki
- Department of Psychiatry and Neurosciences, Institute of Biomedical and Health Sciences, Hiroshima University Hiroshima, Japan
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Nakao T, Matsumoto T, Morita M, Shimizu D, Yoshimura S, Northoff G, Morinobu S, Okamoto Y, Yamawaki S. The Degree of Early Life Stress Predicts Decreased Medial Prefrontal Activations and the Shift from Internally to Externally Guided Decision Making: An Exploratory NIRS Study during Resting State and Self-Oriented Task. Front Hum Neurosci 2013; 7:339. [PMID: 23840186 PMCID: PMC3699719 DOI: 10.3389/fnhum.2013.00339] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 06/16/2013] [Indexed: 01/07/2023] Open
Abstract
Early life stress (ELS), an important risk factor for psychopathology in mental disorders, is associated neuronally with decreased functional connectivity within the default mode network (DMN) in the resting state. Moreover, it is linked with greater deactivation in DMN during a working memory task. Although DMN shows large amplitudes of very low-frequency oscillations (VLFO) and strong involvement during self-oriented tasks, these features’ relation to ELS remains unclear. Therefore, our preliminary study investigated the relationship between ELS and the degree of frontal activations during a resting state and self-oriented task using near-infrared spectroscopy (NIRS). From 22 healthy participants, regional hemodynamic changes in 43 front-temporal channels were recorded during 5 min resting states, and execution of a self-oriented task (color-preference judgment) and a control task (color-similarity judgment). Using a child abuse and trauma scale, ELS was quantified. We observed that ELS showed a negative correlation with medial prefrontal cortex (MPFC) activation during both resting state and color-preference judgment. In contrast, no significant correlation was found between ELS and MPFC activation during color-similarity judgment. Additionally, we observed that ELS and the MPFC activation during color-preference judgment were associated behaviorally with the rate of similar color choice in preference judgment, which suggests that, for participants with higher ELS, decisions in the color-preference judgment were based on an external criterion (color similarity) rather than an internal criterion (subjective preference). Taken together, our neuronal and behavioral findings show that high ELS is related to lower MPFC activation during both rest and self-oriented tasks. This is behaviorally manifest in an abnormal shift from internally to externally guided decision making, even under circumstances where internal guidance is required.
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Affiliation(s)
- Takashi Nakao
- Department of Psychology, Graduate School of Education, Hiroshima University , Hiroshima , Japan
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35
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Fantini S. Dynamic model for the tissue concentration and oxygen saturation of hemoglobin in relation to blood volume, flow velocity, and oxygen consumption: Implications for functional neuroimaging and coherent hemodynamics spectroscopy (CHS). Neuroimage 2013; 85 Pt 1:202-21. [PMID: 23583744 DOI: 10.1016/j.neuroimage.2013.03.065] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 03/13/2013] [Accepted: 03/25/2013] [Indexed: 11/30/2022] Open
Abstract
This article presents a dynamic model that quantifies the temporal evolution of the concentration and oxygen saturation of hemoglobin in tissue, as determined by time-varying hemodynamic and metabolic parameters: blood volume, flow velocity, and oxygen consumption. This multi-compartment model determines separate contributions from arterioles, capillaries, and venules that comprise the tissue microvasculature, and treats them as a complete network, without making assumptions on the details of the architecture and morphology of the microvascular bed. A key parameter in the model is the effective blood transit time through the capillaries and its associated probability of oxygen release from hemoglobin to tissue, as described by a rate constant for oxygen diffusion. The solution of the model in the time domain predicts the signals measured by hemodynamic-based neuroimaging techniques such as functional near-infrared spectroscopy (fNIRS) and functional magnetic resonance imaging (fMRI) in response to brain activation. In the frequency domain, the model yields an analytical solution based on a phasor representation that provides a framework for quantitative spectroscopy of coherent hemodynamic oscillations. I term this novel technique coherent hemodynamics spectroscopy (CHS), and this article describes how it can be used for the assessment of cerebral autoregulation and the study of hemodynamic oscillations resulting from a variety of periodic physiological challenges, brain activation protocols, or physical maneuvers.
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Affiliation(s)
- Sergio Fantini
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA.
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Pierro ML, Hallacoglu B, Sassaroli A, Kainerstorfer JM, Fantini S. Validation of a novel hemodynamic model for coherent hemodynamics spectroscopy (CHS) and functional brain studies with fNIRS and fMRI. Neuroimage 2013; 85 Pt 1:222-33. [PMID: 23562703 DOI: 10.1016/j.neuroimage.2013.03.037] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 03/13/2013] [Accepted: 03/25/2013] [Indexed: 01/08/2023] Open
Abstract
We report an experimental validation and applications of the new hemodynamic model presented in the companion article (Fantini, 2014-this issue) both in the frequency domain and in the time domain. In the frequency domain, we have performed diffuse optical measurements for coherent hemodynamics spectroscopy (CHS) on the brain and calf muscle of human subjects, showing that the hemodynamic model predictions (both in terms of spectral shapes and absolute spectral values) are confirmed experimentally. We show how the quantitative analysis based on the new model allows for autoregulation measurements from brain data, and provides an analytical description of near-infrared spiroximetry from muscle data. In the time domain, we have used data from the literature to perform a comparison between brain activation signals measured with functional near-infrared spectroscopy (fNIRS) or with blood oxygenation level dependent (BOLD) fMRI, and the corresponding signals predicted by the new model. This comparison shows an excellent agreement between the model predictions and the reported fNIRS and BOLD fMRI signals. This new hemodynamic model provides a valuable tool for brain studies with hemodynamic-based techniques.
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Affiliation(s)
- Michele L Pierro
- Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA.
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Kuo JR, Chang MH, Wang CC, Chio CC, Wang JJ, Lin BS. Wireless near-infrared spectroscopy system for determining brain hemoglobin levels in laboratory animals. J Neurosci Methods 2013; 214:204-9. [PMID: 23391759 DOI: 10.1016/j.jneumeth.2013.01.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 01/27/2013] [Accepted: 01/28/2013] [Indexed: 10/27/2022]
Abstract
Traumatic brain injury (TBI) is usually caused by brain shaking or impact. It can affect normal brain function and may even lead to disability or death. However, there are very few studies on the associated physiologic changes in humans or animals. In this study, a non-invasive, wireless multi-channel near-infrared spectroscopy (NIRS) was developed to continuously monitor the concentration change of oxyhemoglobin (HbO2), deoxyhemoglobin (HbR), and total hemoglobin (HbT) to elucidate changes in the physiological state of the brain during and after different strength impaction. The triphenyltetrazolium chloride (TTC) staining was also used to monitor changes of infarction volume after different strength impaction. The results indicated that the concentration changes of HbO2 and HbT, and the changes of infarction volumes were significantly related to the impact strength. In conclusion, the status of TBI can be clinically evaluated by detecting HbO2 and HbT changes. The system proposed here is stable, accurate, non-invasive, and mostly important wireless which can easily be used for TBI study.
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Affiliation(s)
- Jinn-Rung Kuo
- Division of Neurosurgery, Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan
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Aritake S, Higuchi S, Suzuki H, Kuriyama K, Enomoto M, Soshi T, Kitamura S, Hida A, Mishima K. Increased cerebral blood flow in the right frontal lobe area during sleep precedes self-awakening in humans. BMC Neurosci 2012; 13:153. [PMID: 23256572 PMCID: PMC3538054 DOI: 10.1186/1471-2202-13-153] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2012] [Accepted: 12/11/2012] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Some people can subconsciously wake up naturally (self-awakening) at a desired/planned time without external time stimuli. However, the underlying mechanism regulating this ability remains to be elucidated. This study sought to examine the relationship between hemodynamic changes in oxyhemoglobin (oxy-Hb) level in the prefrontal cortex and sleep structures during sleep in subjects instructed to self-awaken. RESULTS Fifteen healthy right-handed male volunteers with regular sleep habits participated in a consecutive two-night crossover study. The subjects were instructed to wake up at a specified time ("request" condition) or instructed to sleep until the morning but forced to wake up at 03:00 without prior notice ("surprise" condition). Those who awoke within ± 30 min of the planned waking time were defined as those who succeeded in self-awakening ("success" group). Seven subjects succeeded in self-awakening and eight failed.No significant differences were observed in the amounts of sleep in each stage between conditions or between groups. On the "request" night, an increase in oxy-Hb level in the right prefrontal cortex and a decrease in δ power were observed in the "success" group around 30 min before self-awakening, whereas no such changes were observed in the "failure" group. On the "surprise" night, no significant changes were observed in oxy-Hb level or δ power in either group. CONCLUSIONS These findings demonstrate a correlation between self-awakening and a pre-awakening increase in hemodynamic activation in the right prefrontal cortex, suggesting the structure's contribution to time estimation ability.
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Affiliation(s)
- Sayaka Aritake
- Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8502, Japan
- Japan Society for the Promotion of Science, Tokyo, 102-8471, Japan
- Department of Somnology, Tokyo Medical University, Tokyo, 160-0023, Japan
- Department of Life Sciences and Bio-informatics, Graduate School of Allied Health Sciences, Tokyo Medical and Dental University, Tokyo, 113-0034, Japan
| | - Shigekazu Higuchi
- Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8502, Japan
- Department of Human Science, Faculty of Design, Kyushu University, Fukuoka, 815-8540, Japan
| | - Hiroyuki Suzuki
- Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8502, Japan
| | - Kenichi Kuriyama
- Department of Adult Mental Health, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8502, Japan
| | - Minori Enomoto
- Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8502, Japan
- Department of Life Sciences and Bio-informatics, Graduate School of Allied Health Sciences, Tokyo Medical and Dental University, Tokyo, 113-0034, Japan
| | - Takahiro Soshi
- Department of Adult Mental Health, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8502, Japan
| | - Shingo Kitamura
- Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8502, Japan
| | - Akiko Hida
- Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8502, Japan
| | - Kazuo Mishima
- Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8502, Japan
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