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Baena-Caldas GP, Li J, Pedraza L, Ghosh S, Kalmes A, Barone FC, Moreno H, Hernández AI. Neuroprotective effect of the RNS60 in a mouse model of transient focal cerebral ischemia. PLoS One 2024; 19:e0295504. [PMID: 38166102 PMCID: PMC10760892 DOI: 10.1371/journal.pone.0295504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Accepted: 11/22/2023] [Indexed: 01/04/2024] Open
Abstract
BACKGROUND Stroke is a major cause of death, disability, and public health problems. Its intervention is limited to early treatment with thrombolytics and/or endovascular clot removal with mechanical thrombectomy without any available subacute or chronic neuroprotective treatments. RNS60 has reduced neuroinflammation and increased neuronal survival in several animal models of neurodegeneration and trauma. The aim here was to evaluate whether RNS60 protects the brain and cognitive function in a mouse stroke model. METHODS Male C57BL/6J mice were subjected to sham or ischemic stroke surgery using 60-minute transient middle cerebral artery occlusion (tMCAo). In each group, mice received blinded daily administrations of RNS60 or control fluids (PNS60 or normal saline [NS]), beginning 2 hours after surgery over 13 days. Multiple neurobehavioral tests were conducted (Neurological Severity Score [mNSS], Novel Object Recognition [NOR], Active Place Avoidance [APA], and the Conflict Variant of APA [APAc]). On day 14, cortical microvascular perfusion (MVP) was measured, then brains were removed and infarct volume, immunofluorescence of amyloid beta (Aβ), neuronal density, microglial activation, and white matter damage/myelination were measured. SPSS was used for analysis (e.g., ANOVA for parametric data; Kruskal Wallis for non-parametric data; with post-hoc analysis). RESULTS Thirteen days of treatment with RNS60 reduced brain infarction, amyloid pathology, neuronal death, microglial activation, white matter damage, and increased MVP. RNS60 reduced brain pathology and resulted in behavioral improvements in stroke compared to sham surgery mice (increased memory-learning in NOR and APA, improved cognitive flexibility in APAc). CONCLUSION RNS60-treated mice exhibit significant protection of brain tissue and improved neurobehavioral functioning after tMCAo-stroke. Additional work is required to determine mechanisms, time-window of dosing, and multiple dosing volumes durations to support clinical stroke research.
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Affiliation(s)
- Gloria Patricia Baena-Caldas
- Departments of Neurology and Physiology & Pharmacology, SUNY Downstate Health Sciences University, Brooklyn, NY, United States of America
- Department of Pathology, SUNY Downstate Health Sciences University, Brooklyn, NY, United States of America
- Health Sciences Division, Department of Morphology, School of Biomedical Sciences, Universidad del Valle, Cali, Colombia
| | - Jie Li
- Departments of Neurology and Physiology & Pharmacology, SUNY Downstate Health Sciences University, Brooklyn, NY, United States of America
| | - Lina Pedraza
- Departments of Neurology and Physiology & Pharmacology, SUNY Downstate Health Sciences University, Brooklyn, NY, United States of America
| | - Supurna Ghosh
- Revalesio Corporation, Tacoma, WA, United States of America
| | - Andreas Kalmes
- Revalesio Corporation, Tacoma, WA, United States of America
| | - Frank C. Barone
- Departments of Neurology and Physiology & Pharmacology, SUNY Downstate Health Sciences University, Brooklyn, NY, United States of America
- The Robert F. Furchgott Center for Neural and Behavioral Science, Downstate Medical Center, State University of New York, Brooklyn, NY, United States of America
| | - Herman Moreno
- Departments of Neurology and Physiology & Pharmacology, SUNY Downstate Health Sciences University, Brooklyn, NY, United States of America
- The Robert F. Furchgott Center for Neural and Behavioral Science, Downstate Medical Center, State University of New York, Brooklyn, NY, United States of America
| | - A. Iván Hernández
- Department of Pathology, SUNY Downstate Health Sciences University, Brooklyn, NY, United States of America
- The Robert F. Furchgott Center for Neural and Behavioral Science, Downstate Medical Center, State University of New York, Brooklyn, NY, United States of America
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Wang Q, Pan M, Zang Z, Li DDU. Quantification of blood flow index in diffuse correlation spectroscopy using a robust deep learning method. JOURNAL OF BIOMEDICAL OPTICS 2024; 29:015004. [PMID: 38283935 PMCID: PMC10821781 DOI: 10.1117/1.jbo.29.1.015004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 12/22/2023] [Accepted: 01/02/2024] [Indexed: 01/30/2024]
Abstract
Significance Diffuse correlation spectroscopy (DCS) is a powerful, noninvasive optical technique for measuring blood flow. Traditionally the blood flow index (BFi) is derived through nonlinear least-square fitting the measured intensity autocorrelation function (ACF). However, the fitting process is computationally intensive, susceptible to measurement noise, and easily influenced by optical properties (absorption coefficient μ a and reduced scattering coefficient μ s ' ) and scalp and skull thicknesses. Aim We aim to develop a data-driven method that enables rapid and robust analysis of multiple-scattered light's temporal ACFs. Moreover, the proposed method can be applied to a range of source-detector distances instead of being limited to a specific source-detector distance. Approach We present a deep learning architecture with one-dimensional convolution neural networks, called DCS neural network (DCS-NET), for BFi and coherent factor (β ) estimation. This DCS-NET was performed using simulated DCS data based on a three-layer brain model. We quantified the impact from physiologically relevant optical property variations, layer thicknesses, realistic noise levels, and multiple source-detector distances (5, 10, 15, 20, 25, and 30 mm) on BFi and β estimations among DCS-NET, semi-infinite, and three-layer fitting models. Results DCS-NET shows a much faster analysis speed, around 17,000-fold and 32-fold faster than the traditional three-layer and semi-infinite models, respectively. It offers higher intrinsic sensitivity to deep tissues compared with fitting methods. DCS-NET shows excellent anti-noise features and is less sensitive to variations of μ a and μ s ' at a source-detector separation of 30 mm. Also, we have demonstrated that relative BFi (rBFi) can be extracted by DCS-NET with a much lower error of 8.35%. By contrast, the semi-infinite and three-layer fitting models result in significant errors in rBFi of 43.76% and 19.66%, respectively. Conclusions DCS-NET can robustly quantify blood flow measurements at considerable source-detector distances, corresponding to much deeper biological tissues. It has excellent potential for hardware implementation, promising continuous real-time blood flow measurements.
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Affiliation(s)
- Quan Wang
- University of Strathclyde, Department of Biomedical Engineering, Faculty of Engineering, Glasgow, United Kingdom
| | - Mingliang Pan
- University of Strathclyde, Department of Biomedical Engineering, Faculty of Engineering, Glasgow, United Kingdom
| | - Zhenya Zang
- University of Strathclyde, Department of Biomedical Engineering, Faculty of Engineering, Glasgow, United Kingdom
| | - David Day-Uei Li
- University of Strathclyde, Department of Biomedical Engineering, Faculty of Engineering, Glasgow, United Kingdom
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Li W, Zhang Z, Li Z, Gui Z, Shang Y. Correlation and asynchronization of electroencephalogram and cerebral blood flow in active and passive stimulations. J Neural Eng 2023; 20:066007. [PMID: 37931297 DOI: 10.1088/1741-2552/ad0a02] [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: 05/20/2023] [Accepted: 11/06/2023] [Indexed: 11/08/2023]
Abstract
Objective.Real-time brain monitoring is of importance for intraoperative surgeries and intensive care unit, in order to take timely clinical interventions. Electroencephalogram (EEG) is a conventional technique for recording neural excitations (e.g. brain waves) in the cerebral cortex, and near infrared diffuse correlation spectroscopy (DCS) is an emerging technique that can directly measure the cerebral blood flow (CBF) in microvasculature system. Currently, the relationship between the neural activities and cerebral hemodynamics that reflects the vasoconstriction features of cerebral vessels, especially under both active and passive situation, has not been elucidated thus far, which triggers the motivation of this study.Approach.We used the verbal fluency test as an active cognitive stimulus to the brain, and we manipulated blood pressure changes as a passive challenge to the brain. Under both protocols, the CBF and EEG responses were longitudinally monitored throughout the cerebral stimulus. Power spectrum approaches were applied the EEG signals and compared with CBF responses.Main results.The results show that the EEG response was significantly faster and larger in amplitude during the active cognitive task, when compared to the CBF, but with larger individual variability. By contrast, CBF is more sensitive when response to the passive task, and with better signal stability. We also found that there was a correlation (p< 0.01,r= 0.866,R2= 0.751) between CBF and EEG in initial response during the active task, but no significant correlation (p> 0.05) was found during the passive task. The similar relations were also found between regional brain waves and blood flow.Significance.The asynchronization and correlation between the two measurements indicates the necessity of monitoring both variables for comprehensive understanding of cerebral physiology. Deep exploration of their relationships provides promising implications for DCS/EEG integration in the diagnosis of various neurovascular and psychiatric diseases.
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Affiliation(s)
- Weilong Li
- State Key Laboratory of Dynamic Measurement Technology, North University of China, Taiyuan, People's Republic of China
| | - Zihao Zhang
- School of Electronics and Information Engineering, Harbin Institute of Technology, Harbin, People's Republic of China
| | - Zhiyi Li
- Electronic Information College, Northwestern Polytechnical University, Xian, People's Republic of China
| | - Zhiguo Gui
- State Key Laboratory of Dynamic Measurement Technology, North University of China, Taiyuan, People's Republic of China
| | - Yu Shang
- State Key Laboratory of Dynamic Measurement Technology, North University of China, Taiyuan, People's Republic of China
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Mohtasebi M, Singh D, Liu X, Fathi F, Haratbar SR, Saatman KE, Chen L, Yu G. Depth-sensitive diffuse speckle contrast topography for high-density mapping of cerebral blood flow in rodents. NEUROPHOTONICS 2023; 10:045007. [PMID: 38076725 PMCID: PMC10704187 DOI: 10.1117/1.nph.10.4.045007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 10/26/2023] [Accepted: 10/27/2023] [Indexed: 02/12/2024]
Abstract
Significance Frequent assessment of cerebral blood flow (CBF) is crucial for the diagnosis and management of cerebral vascular diseases. In contrast to large and expensive imaging modalities, such as nuclear medicine and magnetic resonance imaging, optical imaging techniques are portable and inexpensive tools for continuous measurements of cerebral hemodynamics. The recent development of an innovative noncontact speckle contrast diffuse correlation tomography (scDCT) enables three-dimensional (3D) imaging of CBF distributions. However, scDCT requires complex and time-consuming 3D reconstruction, which limits its ability to achieve high spatial resolution without sacrificing temporal resolution and computational efficiency. Aim We investigate a new diffuse speckle contrast topography (DSCT) method with parallel computation for analyzing scDCT data to achieve fast and high-density two-dimensional (2D) mapping of CBF distributions at different depths without the need for 3D reconstruction. Approach A new moving window method was adapted to improve the sampling rate of DSCT. A fast computation method utilizing MATLAB functions in the Image Processing Toolbox™ and Parallel Computing Toolbox™ was developed to rapidly generate high-density CBF maps. The new DSCT method was tested for spatial resolution and depth sensitivity in head-simulating layered phantoms and in-vivo rodent models. Results DSCT enables 2D mapping of the particle flow in the phantom at different depths through the top layer with varied thicknesses. Both DSCT and scDCT enable the detection of global and regional CBF changes in deep brains of adult rats. However, DSCT achieves fast and high-density 2D mapping of CBF distributions at different depths without the need for complex and time-consuming 3D reconstruction. Conclusions The depth-sensitive DSCT method has the potential to be used as a noninvasive, noncontact, fast, high resolution, portable, and inexpensive brain imager for basic neuroscience research in small animal models and for translational studies in human neonates.
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Affiliation(s)
- Mehrana Mohtasebi
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky, United States
| | - Dara Singh
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky, United States
| | - Xuhui Liu
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky, United States
| | - Faraneh Fathi
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky, United States
| | | | - Kathryn E. Saatman
- University of Kentucky, Spinal Cord and Brain Injury Research Center, Department of Physiology, Lexington, Kentucky, United States
| | - Lei Chen
- University of Kentucky, Spinal Cord and Brain Injury Research Center, Department of Physiology, Lexington, Kentucky, United States
| | - Guoqiang Yu
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky, United States
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Zhai L, Du Y, Fu Y, Wu X. Laser speckle contrast imaging based on spatial frequency domain filtering. JOURNAL OF BIOPHOTONICS 2023; 16:e202300108. [PMID: 37260409 DOI: 10.1002/jbio.202300108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 05/08/2023] [Accepted: 05/26/2023] [Indexed: 06/02/2023]
Abstract
We proposed a novel method to separate static and dynamic speckles based on spatial frequency domain filtering. First, the raw speckle image sequence is processed frame by frame through 2D Fourier transform, low-pass and high-pass filtering in the spatial frequency domain, and inverse Fourier transform. Then, we can obtain low- and high-frequency image sequences in the spatial domain. Second, we averaged both sequences in the time domain. After the above processing, we obtain the mean intensities of the dynamic and static speckle components in the spatial domain. Finally, we calculated the time-averaged modulation depth to map the 2-D blood flow distribution. Both phantom and vivo experiments demonstrated that the proposed method could effectively suppress the background non-uniformity and has the advantage of high computational efficiency. It also can effectively improve image contrast, contrast-to-noise ratio, and imaging dynamic range.
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Affiliation(s)
- Linjun Zhai
- School of Biomedical Science, Huaqiao University, Quanzhou, China
| | - Yongzhao Du
- School of Biomedical Science, Huaqiao University, Quanzhou, China
- College of Engineering, Huaqiao University, Quanzhou, China
| | - Yuqing Fu
- College of Engineering, Huaqiao University, Quanzhou, China
| | - Xunxun Wu
- School of Biomedical Science, Huaqiao University, Quanzhou, China
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Liu X, Irwin DA, Huang C, Gu Y, Chen L, Donohue KD, Chen L, Yu G. A Wearable Fiber-Free Optical Sensor for Continuous Monitoring of Cerebral Blood Flow in Freely Behaving Mice. IEEE Trans Biomed Eng 2023; 70:1838-1848. [PMID: 37015409 PMCID: PMC10542964 DOI: 10.1109/tbme.2022.3229513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Wearable technologies for functional brain monitoring in freely behaving subjects can advance our understanding of cognitive processing and adaptive behavior. Existing technologies are lacking in this capability or need procedures that are invasive and/or otherwise impede brain assessments during social behavioral conditions, exercise, and sleep. METHODS In response a complete system was developed to combine relative cerebral blood flow (rCBF) measurement, O2 and CO2 supplies, and behavior recording for use on conscious, freely behaving mice. An innovative diffuse speckle contrast flowmetry (DSCF) device and associated hardware were miniaturized and optimized for rCBF measurements in small subject applications. The use of this wearable, fiber-free, near-infrared DSCF head-stage/probe allowed no craniotomy, minimally invasive probe implantation, and minimal restraint of the awake animal. RESULTS AND CONCLUSIONS Significant correlations were found between measurements with the new DSCF design and an optical standard. The system successfully detected rCBF responses to CO2-induced hypercapnia in both anesthetized and freely behaving mice. SIGNIFICANCE Collecting rCBF and activity information together during natural behaviors provides realistic physiological results and opens the path to exploring their correlations with pathophysiological conditions.
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Affiliation(s)
- Xuhui Liu
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Daniel A. Irwin
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Chong Huang
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Yutong Gu
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Li Chen
- Biostatistics and Bioinformatics Shared Resource Facility, Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - Kevin D. Donohue
- Department of Electrical and Computer Engineering, University of Kentucky, Lexington, KY, USA
| | - Lei Chen
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY, USA
| | - Guoqiang Yu
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
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Fu C, Wang D, Wang L, Zhu L, Li Z, Chen T, Feng H, Li F. Diffuse optical detection of global cerebral ischemia in an adult porcine model. JOURNAL OF BIOPHOTONICS 2023; 16:e202200168. [PMID: 36397661 DOI: 10.1002/jbio.202200168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 11/13/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
Rapid screening for ischemic strokes in prehospital settings may improve patient outcomes by allowing early deployment of vascular recanalization therapies. However, there are no low-cost and convenient methods that can assess ischemic strokes in such a setting. Diffuse correlation spectroscopy (DCS) is a promising method for continuous, noninvasive transcranial monitoring of cerebral blood flow. In this study, we used a DCS system to detect cerebral hemodynamics before and after acute ischemic stroke in pigs. Seven adult porcines were chosen to establish ischemic stroke models via bilateral common carotid artery ligation (n = 5) or air emboli (n = 2). The results showed a significant difference in blood flow index (BFI) between the normal and ischemic groups. Relative blood flow index (rBFI) exhibited excellent results. Therefore, the diffuse optical method can assess the hemodynamic changes in acute cerebral ischemic stroke onset in pigs, and rBFI may be a promising biomarker for identifying cerebral ischemic stroke.
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Affiliation(s)
- Chuhua Fu
- Department of Neurosurgery of Southwest Hospital, Army Medical University, Chong Qing, People's Republic of China
- Department of Neurosurgery, Xiangyang No.1 People's Hospital, Hubei University of Medicine, Xiangyang, People's Republic of China
| | - Detian Wang
- Department of Neurosurgery of Southwest Hospital, Army Medical University, Chong Qing, People's Republic of China
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan, People's Republic of China
| | - Long Wang
- Department of Neurosurgery of Southwest Hospital, Army Medical University, Chong Qing, People's Republic of China
| | - Liguo Zhu
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan, People's Republic of China
| | - Zeren Li
- Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan, People's Republic of China
| | - Tunan Chen
- Department of Neurosurgery of Southwest Hospital, Army Medical University, Chong Qing, People's Republic of China
| | - Hua Feng
- Department of Neurosurgery of Southwest Hospital, Army Medical University, Chong Qing, People's Republic of China
| | - Fei Li
- Department of Neurosurgery of Southwest Hospital, Army Medical University, Chong Qing, People's Republic of China
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Gomez A, Sainbhi AS, Froese L, Batson C, Slack T, Stein KY, Cordingley DM, Mathieu F, Zeiler FA. The Quantitative Associations Between Near Infrared Spectroscopic Cerebrovascular Metrics and Cerebral Blood Flow: A Scoping Review of the Human and Animal Literature. Front Physiol 2022; 13:934731. [PMID: 35910568 PMCID: PMC9335366 DOI: 10.3389/fphys.2022.934731] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 06/09/2022] [Indexed: 11/13/2022] Open
Abstract
Cerebral blood flow (CBF) is an important physiologic parameter that is vital for proper cerebral function and recovery. Current widely accepted methods of measuring CBF are cumbersome, invasive, or have poor spatial or temporal resolution. Near infrared spectroscopy (NIRS) based measures of cerebrovascular physiology may provide a means of non-invasively, topographically, and continuously measuring CBF. We performed a systematically conducted scoping review of the available literature examining the quantitative relationship between NIRS-based cerebrovascular metrics and CBF. We found that continuous-wave NIRS (CW-NIRS) was the most examined modality with dynamic contrast enhanced NIRS (DCE-NIRS) being the next most common. Fewer studies assessed diffuse correlation spectroscopy (DCS) and frequency resolved NIRS (FR-NIRS). We did not find studies examining the relationship between time-resolved NIRS (TR-NIRS) based metrics and CBF. Studies were most frequently conducted in humans and animal studies mostly utilized large animal models. The identified studies almost exclusively used a Pearson correlation analysis. Much of the literature supported a positive linear relationship between changes in CW-NIRS based metrics, particularly regional cerebral oxygen saturation (rSO2), and changes in CBF. Linear relationships were also identified between other NIRS based modalities and CBF, however, further validation is needed.
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Affiliation(s)
- Alwyn Gomez
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- Section of Neurosurgery, Department of Surgery, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- *Correspondence: Alwyn Gomez,
| | - Amanjyot Singh Sainbhi
- Biomedical Engineering, Faculty of Engineering, University of Manitoba, Winnipeg, MB, Canada
| | - Logan Froese
- Biomedical Engineering, Faculty of Engineering, University of Manitoba, Winnipeg, MB, Canada
| | - Carleen Batson
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Trevor Slack
- Biomedical Engineering, Faculty of Engineering, University of Manitoba, Winnipeg, MB, Canada
| | - Kevin Y. Stein
- Biomedical Engineering, Faculty of Engineering, University of Manitoba, Winnipeg, MB, Canada
| | - Dean M. Cordingley
- Applied Health Sciences Program, University of Manitoba, Winnipeg, MB, Canada
- Pan Am Clinic Foundation, Winnipeg, MB, Canada
| | - Francois Mathieu
- Interdepartmental Division of Critical Care, Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Frederick A. Zeiler
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- Section of Neurosurgery, Department of Surgery, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- Biomedical Engineering, Faculty of Engineering, University of Manitoba, Winnipeg, MB, Canada
- Centre on Aging, University of Manitoba, Winnipeg, MB, Canada
- Division of Anaesthesia, Department of Medicine, Addenbrooke’s Hospital, University of Cambridge, Cambridge, MA, United Kingdom
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
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Zhao B, Jiang X. hsa-miR-518-5p/hsa-miR-3135b Regulates the REL/SOD2 Pathway in Ischemic Cerebral Infarction. Front Neurol 2022; 13:852013. [PMID: 35481271 PMCID: PMC9038098 DOI: 10.3389/fneur.2022.852013] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 02/24/2022] [Indexed: 12/12/2022] Open
Abstract
ObjectivesIschemic cerebral infarction (ICI) is a fatal neurovascular disorder. A bioinformatics approach based on single-cell and bulk RNA-seq analyses was applied to investigate the pathways and genes involved in ICI and study the expression profile of these genes.MethodsFirst, the aberrantly regulated “small-molecule ribonucleic acids” [microRNA (miRNAs)] and messenger RNAs (mRNAs) were analyzed using transcriptome data from the ischemic brain infarction dataset of the Gene Expression Omnibus (GEO) database. In mouse cerebrovascular monocytes, the single-cell regulatory network inference and clustering (SCENIC) workflow was used to identify key transcription factors (TFs). Then, the two miRNA-TF-mRNA interaction networks were constructed. Moreover, the molecular complex detection (MCODE) extracted the core sub-networks and identified the important TFs within these sub-networks. Finally, whole blood samples were collected for validation of the expression of critical molecules in ICI.ResultsWe identified four cell types and 266 regulons in mouse cerebrovascular monocytes using SCENIC analysis. Moreover, 112 differently expressed miRNAs and 3,780 differentially expressed mRNAs were identified. We discovered potential biomarkers in ICI by building a miRNA-TF-mRNA interaction network. The hsa-miR-518-5p/hsa-miR-3135b/REL/SOD2 was found to play a potential role in ICI progression. The expression of REL and superoxide dismutase 2 (SOD2) was significantly elevated in the ICI group in the clinical cohort (P < 0.05). Furthermore, a REL expression was elevated in endothelial cells and fibroblasts at the single-cell level, indicating that REL is a cell-specific regulon. Functional enrichment analyses revealed that REL is primarily engaged in neurotransmitter activity and oxidative phosphorylation.ConclusionsOur research uncovered novel biomarkers for ICI of neurovascular disease. The hsa-miR-518-5p/hsa-miR-3135b may regulate the REL/SOD2 pathway in ICI progression.
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Optical Modalities for Research, Diagnosis, and Treatment of Stroke and the Consequent Brain Injuries. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12041891] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Stroke is the second most common cause of death and third most common cause of disability worldwide. Therefore, it is an important disease from a medical standpoint. For this reason, various studies have developed diagnostic and therapeutic techniques for stroke. Among them, developments and applications of optical modalities are being extensively studied. In this article, we explored three important optical modalities for research, diagnostic, and therapeutics for stroke and the brain injuries related to it: (1) photochemical thrombosis to investigate stroke animal models; (2) optical imaging techniques for in vivo preclinical studies on stroke; and (3) optical neurostimulation based therapy for stroke. We believe that an exploration and an analysis of previous studies will help us proceed from research to clinical applications of optical modalities for research, diagnosis, and treatment of stroke.
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Samaei S, Colombo L, Borycki D, Pagliazzi M, Durduran T, Sawosz P, Wojtkiewicz S, Contini D, Torricelli A, Pifferi A, Liebert A. Performance assessment of laser sources for time-domain diffuse correlation spectroscopy. BIOMEDICAL OPTICS EXPRESS 2021; 12:5351-5367. [PMID: 34692187 PMCID: PMC8515963 DOI: 10.1364/boe.432363] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 05/02/2023]
Abstract
Time-domain diffuse correlation spectroscopy (TD-DCS) is an emerging optical technique that enables noninvasive measurement of microvascular blood flow with photon path-length resolution. In TD-DCS, a picosecond pulsed laser with a long coherence length, adequate illumination power, and narrow instrument response function (IRF) is required, and satisfying all these features is challenging. To this purpose, in this study we characterized the performance of three different laser sources for TD-DCS. First, the sources were evaluated based on their emission spectrum and IRF. Then, we compared the signal-to-noise ratio and the sensitivity to velocity changes of scattering particles in a series of phantom measurements. We also compared the results for in vivo measurements, performing an arterial occlusion protocol on the forearm of three adult subjects. Overall, each laser has the potential to be successfully used both for laboratory and clinical applications. However, we found that the effects caused by the IRF are more significant than the effect of a limited temporal coherence.
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Affiliation(s)
- Saeed Samaei
- Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Ks. Trojdena 4, 02-109, Warsaw, Poland
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Lorenzo Colombo
- Politecnico di Milano, Dipartimento di Fisica, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Dawid Borycki
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
- International Centre for Translational Eye Research, Skierniewicka 10A, 01-230 Warsaw, Poland
| | - Marco Pagliazzi
- ICFO—Institut de Ciències Fotòniques, Mediterranean Technology Park, Avinguda Carl Friedrich Gauss 3, 08860 Castelldefels, Barcelona, Spain
| | - Turgut Durduran
- ICFO—Institut de Ciències Fotòniques, Mediterranean Technology Park, Avinguda Carl Friedrich Gauss 3, 08860 Castelldefels, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig de Lluís Companys 23, 08010 Barcelona, Spain
| | - Piotr Sawosz
- Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Ks. Trojdena 4, 02-109, Warsaw, Poland
| | - Stanislaw Wojtkiewicz
- Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Ks. Trojdena 4, 02-109, Warsaw, Poland
| | - Davide Contini
- Politecnico di Milano, Dipartimento di Fisica, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Alessandro Torricelli
- Politecnico di Milano, Dipartimento di Fisica, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
- Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Antonio Pifferi
- Politecnico di Milano, Dipartimento di Fisica, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
- Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Adam Liebert
- Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Ks. Trojdena 4, 02-109, Warsaw, Poland
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12
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Zhao M, Huang C, Mazdeyasna S, Yu G. Extraction of tissue optical property and blood flow from speckle contrast diffuse correlation tomography (scDCT) measurements. BIOMEDICAL OPTICS EXPRESS 2021; 12:5894-5908. [PMID: 34692223 PMCID: PMC8515985 DOI: 10.1364/boe.429890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/15/2021] [Accepted: 08/17/2021] [Indexed: 06/13/2023]
Abstract
Measurement of blood flow in tissue provides vital information for the diagnosis and therapeutic monitoring of various vascular diseases. A noncontact, camera-based, near-infrared speckle contrast diffuse correlation tomography (scDCT) technique has been recently developed for 3D imaging of blood flow index (αDB) distributions in deep tissues up to a centimeter. A limitation with the continuous-wave scDCT measurement of blood flow is the assumption of constant and homogenous tissue absorption coefficient (μ a ). The present study took the advantage of rapid, high-density, noncontact scDCT measurements of both light intensities and diffuse speckle contrast at multiple source-detector distances and developed two-step fitting algorithms for extracting both μ a and αDB. The new algorithms were tested in tissue-simulating phantoms with known optical properties and human forearms. Measurement results were compared against established near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS) techniques. The accuracies of our new fitting algorithms with scDCT measurements in phantoms (up to 16% errors) and forearms (up to 23% errors) are comparable to relevant study results (up to 25% errors). Knowledge of μ a not only improved the accuracy in calculating αDB but also provided the potential for quantifying tissue blood oxygenation via spectral measurements. A multiple-wavelength scDCT system with new algorithms is currently developing to fit multi-wavelength and multi-distance data for 3D imaging of both blood flow and oxygenation distributions in deep tissues.
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13
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Feng S, Gui Z, Zhang X, Shang Y. Collimating micro-lens fiber array for noncontact near-infrared diffuse correlation tomography. BIOMEDICAL OPTICS EXPRESS 2021; 12:1467-1481. [PMID: 33796366 PMCID: PMC7984780 DOI: 10.1364/boe.413734] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 02/06/2021] [Accepted: 02/06/2021] [Indexed: 06/01/2023]
Abstract
Near-infrared diffuse correlation spectroscopy/tomography (DCS/DCT) has recently emerged as a noninvasive measurement/imaging technology for tissue blood flow. In DCT studies, the high-dense collection of light temporal autocorrelation curves (g 2(τ)) via fiber array are critical for image reconstruction of blood flow. Previously, the camera-based fiber array limits the field of view (FOV), precluding its applications on large-size human tissues. The line-shape fiber probe based on lens combination, which is predominantly used in current DCT studies, requires rotated-scanning over the surface of target tissue, substantially prolonging the measurement time and increasing the system instability. In this study, we design a noncontact optical probe for DCT based on collimating micro-lens fiber array, termed as FA-nc-DCT system. For each source/detector fiber, a single optical path was collimated by coupling with one micro-lens in the fiber array that is integrated in a square-shape base. Additionally, an 8×8 optical switch is used to share the hardware laser and detectors without spatial scanning. The FA-nc approach for the precise collection of g 2(τ) curves was validated through a speed-varied phantom experiment and the human experiments of cuff occlusion, from which the expected value of the blood flow index (BFI) was obtained. Furthermore, the flow anomaly in the phantom and the ischemic muscle in human were accurately reconstructed from the FA-nc-DCT system, which is combined with the imaging framework based on the Nth-order linear algorithm that we recently created. Those outcomes demonstrated the great potential of FA-nc-DCT technology for fast and robust imaging of various diseases such as human breast cancers.
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14
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Hosseini M, Wilson RH, Crouzet C, Amirhekmat A, Wei KS, Akbari Y. Resuscitating the Globally Ischemic Brain: TTM and Beyond. Neurotherapeutics 2020; 17:539-562. [PMID: 32367476 PMCID: PMC7283450 DOI: 10.1007/s13311-020-00856-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Cardiac arrest (CA) afflicts ~ 550,000 people each year in the USA. A small fraction of CA sufferers survive with a majority of these survivors emerging in a comatose state. Many CA survivors suffer devastating global brain injury with some remaining indefinitely in a comatose state. The pathogenesis of global brain injury secondary to CA is complex. Mechanisms of CA-induced brain injury include ischemia, hypoxia, cytotoxicity, inflammation, and ultimately, irreversible neuronal damage. Due to this complexity, it is critical for clinicians to have access as early as possible to quantitative metrics for diagnosing injury severity, accurately predicting outcome, and informing patient care. Current recommendations involve using multiple modalities including clinical exam, electrophysiology, brain imaging, and molecular biomarkers. This multi-faceted approach is designed to improve prognostication to avoid "self-fulfilling" prophecy and early withdrawal of life-sustaining treatments. Incorporation of emerging dynamic monitoring tools such as diffuse optical technologies may provide improved diagnosis and early prognostication to better inform treatment. Currently, targeted temperature management (TTM) is the leading treatment, with the number of patients needed to treat being ~ 6 in order to improve outcome for one patient. Future avenues of treatment, which may potentially be combined with TTM, include pharmacotherapy, perfusion/oxygenation targets, and pre/postconditioning. In this review, we provide a bench to bedside approach to delineate the pathophysiology, prognostication methods, current targeted therapies, and future directions of research surrounding hypoxic-ischemic brain injury (HIBI) secondary to CA.
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Affiliation(s)
- Melika Hosseini
- Department of Neurology, School of Medicine, University of California, Irvine, USA
| | - Robert H Wilson
- Department of Neurology, School of Medicine, University of California, Irvine, USA
- Beckman Laser Institute, University of California, Irvine, USA
| | - Christian Crouzet
- Department of Neurology, School of Medicine, University of California, Irvine, USA
- Beckman Laser Institute, University of California, Irvine, USA
| | - Arya Amirhekmat
- Department of Neurology, School of Medicine, University of California, Irvine, USA
| | - Kevin S Wei
- Department of Neurology, School of Medicine, University of California, Irvine, USA
| | - Yama Akbari
- Department of Neurology, School of Medicine, University of California, Irvine, USA.
- Beckman Laser Institute, University of California, Irvine, USA.
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15
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Rosenberry R, Nelson MD. Reactive hyperemia: a review of methods, mechanisms, and considerations. Am J Physiol Regul Integr Comp Physiol 2020; 318:R605-R618. [PMID: 32022580 DOI: 10.1152/ajpregu.00339.2019] [Citation(s) in RCA: 106] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Reactive hyperemia is a well-established technique for noninvasive assessment of peripheral microvascular function and a predictor of all-cause and cardiovascular morbidity and mortality. In its simplest form, reactive hyperemia represents the magnitude of limb reperfusion following a brief period of ischemia induced by arterial occlusion. Over the past two decades, investigators have employed a variety of methods, including brachial artery velocity by Doppler ultrasound, tissue reperfusion by near-infrared spectroscopy, limb distension by venous occlusion plethysmography, and peripheral artery tonometry, to measure reactive hyperemia. Regardless of the technique used to measure reactive hyperemia, blunted reactive hyperemia is believed to reflect impaired microvascular function. With the advent of several technological advancements, together with an increased interest in the microcirculation, reactive hyperemia is becoming more common as a research tool and is widely used across multiple disciplines. With this in mind, we sought to review the various methodologies commonly used to assess reactive hyperemia and current mechanistic pathways believed to contribute to reactive hyperemia and reflect on several methodological considerations.
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Affiliation(s)
- Ryan Rosenberry
- Department of Kinesiology, University of Texas at Arlington, Arlington, Texas
| | - Michael D Nelson
- Department of Kinesiology, University of Texas at Arlington, Arlington, Texas.,Department of Bioengineering, University of Texas at Arlington, Arlington, Texas
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16
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Tucker WJ, Rosenberry R, Trojacek D, Sanchez B, Bentley RF, Haykowsky MJ, Tian F, Nelson MD. Near-infrared diffuse correlation spectroscopy tracks changes in oxygen delivery and utilization during exercise with and without isolated arterial compression. Am J Physiol Regul Integr Comp Physiol 2019; 318:R81-R88. [PMID: 31746636 DOI: 10.1152/ajpregu.00212.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Near-infrared diffuse correlation spectroscopy (NIR-DCS) is an emerging technology for simultaneous measurement of skeletal muscle microvascular oxygen delivery and utilization during exercise. The extent to which NIR-DCS can track acute changes in oxygen delivery and utilization has not yet been fully established. To address this knowledge gap, 14 healthy men performed rhythmic handgrip exercise at 30% maximal voluntary contraction, with and without isolated brachial artery compression, designed to acutely reduce convective oxygen delivery to the exercising muscle. Radial artery blood flow (Duplex Ultrasound) and NIR-DCS derived variables [blood flow index (BFI), tissue oxygen saturation (StO2), and metabolic rate of oxygen (MRO2)] were simultaneously measured. During exercise, both radial artery blood flow (+51.6 ± 20.3 mL/min) and DCS-derived BFI (+155.0 ± 82.2%) increased significantly (P < 0.001), whereas StO2 decreased -7.9 ± 6.2% (P = 0.002) from rest. Brachial artery compression during exercise caused a significant reduction in both radial artery blood flow (-32.0 ± 19.5 mL/min, P = 0.001) and DCS-derived BFI (-57.3 ± 51.1%, P = 0.01) and a further reduction of StO2 (-5.6 ± 3.8%, P = 0.001) compared with exercise without compression. MRO2 was not significantly reduced during arterial compression (P = 0.83) due to compensatory reductions in StO2, driven by increases in deoxyhemoglobin/myoglobin (+7.1 ± 6.1 μM, P = 0.01; an index of oxygen extraction). Together, these proof-of-concept data help to further validate NIR-DCS as an effective tool to assess the determinants of skeletal muscle oxygen consumption at the level of the microvasculature during exercise.
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Affiliation(s)
- Wesley J Tucker
- Department of Kinesiology, University of Texas at Arlington, Arlington, Texas.,College of Nursing, University of Texas at Arlington, Arlington, Texas.,Department of Nutrition & Food Sciences, Texas Woman's University, Houston, Texas
| | - Ryan Rosenberry
- Department of Kinesiology, University of Texas at Arlington, Arlington, Texas
| | - Darian Trojacek
- Department of Kinesiology, University of Texas at Arlington, Arlington, Texas
| | - Belinda Sanchez
- Department of Kinesiology, University of Texas at Arlington, Arlington, Texas
| | - Robert F Bentley
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada
| | - Mark J Haykowsky
- College of Nursing, University of Texas at Arlington, Arlington, Texas
| | - Fenghua Tian
- Department of Bioengineering, University of Texas at Arlington, Arlington, Texas
| | - Michael D Nelson
- Department of Kinesiology, University of Texas at Arlington, Arlington, Texas.,Department of Bioengineering, University of Texas at Arlington, Arlington, Texas
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17
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Huang C, Mazdeyasna S, Chen L, Abu Jawdeh EG, Bada HS, Saatman KE, Chen L, Yu G. Noninvasive noncontact speckle contrast diffuse correlation tomography of cerebral blood flow in rats. Neuroimage 2019; 198:160-169. [DOI: 10.1016/j.neuroimage.2019.05.047] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/16/2019] [Accepted: 05/17/2019] [Indexed: 01/05/2023] Open
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18
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Tucker WJ, Rosenberry R, Trojacek D, Chamseddine HH, Arena-Marshall CA, Zhu Y, Wang J, Kellawan JM, Haykowsky MJ, Tian F, Nelson MD. Studies into the determinants of skeletal muscle oxygen consumption: novel insight from near-infrared diffuse correlation spectroscopy. J Physiol 2019; 597:2887-2901. [PMID: 30982990 DOI: 10.1113/jp277580] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 04/10/2019] [Indexed: 12/12/2022] Open
Abstract
KEY POINTS Diffuse correlation spectroscopy (DCS) is emerging as a powerful tool to assess skeletal muscle perfusion. Near-infrared spectroscopy (NIRS) is an established technique for characterizing the transport and utilization of oxygen through the microcirculation. Here we compared a combined NIRS-DCS system with conventional measures of oxygen delivery and utilization during handgrip exercise. The data show good concurrent validity between convective oxygen delivery and DCS-derived blood flow index, as well as between oxygen extraction at the conduit and microvascular level. We then manipulated forearm arterial perfusion pressure by adjusting the position of the exercising arm relative to the position of the heart. The data show that microvascular perfusion can be uncoupled from convective oxygen delivery, and that tissue saturation seemingly compensates to maintain skeletal muscle oxygen consumption. Taken together, these data support a novel role for NIRS-DCS in understanding the determinants of muscle oxygen consumption at the microvascular level. ABSTRACT Diffuse correlation spectroscopy (DCS) is emerging as a powerful tool to assess skeletal muscle perfusion. Combining DCS with near-infrared spectroscopy (NIRS) introduces exciting possibilities for understanding the determinants of muscle oxygen consumption; however, no investigation has directly compared NIRS-DCS to conventional measures of oxygen delivery and utilization in an exercising limb. To address this knowledge gap, nine healthy males performed rhythmic handgrip exercise with simultaneous measurements by NIRS-DCS, Doppler blood flow and venous oxygen content. The two approaches showed good concurrent validity, with directionally similar responses between: (a) Doppler-derived forearm blood flow and DCS-derived blood flow index (BFI), and (b) venous oxygen saturation and NIRS-derived tissue saturation. To explore the utility of combined NIRS-DCS across the physiological spectrum, we manipulated forearm arterial perfusion pressure by altering the arm position above or below the level of the heart. As expected, Doppler-derived skeletal muscle blood flow increased with exercise in both arm positions, but with markedly different magnitudes (below: +424.3 ± 41.4 ml/min, above: +306 ± 12.0 ml/min, P = 0.002). In contrast, DCS-derived microvascular BFI increased to a similar extent with exercise, regardless of arm position (P = 0.65). Importantly, however, the time to reach BFI steady state was markedly slower with the arm above the heart, supporting the experimental design. Notably, we observed faster tissue desaturation at the onset of exercise with the arm above the heart, resulting in similar muscle oxygen consumption profiles throughout exercise. Taken together, these data support a novel role for NIRS-DCS in understanding the determinants of skeletal muscle oxygen utilization non-invasively and throughout exercise.
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Affiliation(s)
- Wesley J Tucker
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA.,College of Nursing, University of Texas at Arlington, Arlington, TX, USA
| | - Ryan Rosenberry
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
| | - Darian Trojacek
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
| | - Houda H Chamseddine
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
| | | | - Ye Zhu
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA
| | - Jing Wang
- College of Nursing, University of Texas at Arlington, Arlington, TX, USA
| | - J Mikhail Kellawan
- Department of Health and Exercise Science, University of Oklahoma, Norman, OK, USA
| | - Mark J Haykowsky
- College of Nursing, University of Texas at Arlington, Arlington, TX, USA
| | - Fenghua Tian
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA
| | - Michael D Nelson
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA.,Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA
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19
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Portable Near-Infrared Technologies and Devices for Noninvasive Assessment of Tissue Hemodynamics. JOURNAL OF HEALTHCARE ENGINEERING 2019; 2019:3750495. [PMID: 30891170 PMCID: PMC6390246 DOI: 10.1155/2019/3750495] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 12/24/2018] [Accepted: 01/14/2019] [Indexed: 12/29/2022]
Abstract
Tissue hemodynamics, including the blood flow, oxygenation, and oxygen metabolism, are closely associated with many diseases. As one of the portable optical technologies to explore human physiology and assist in healthcare, near-infrared diffuse optical spectroscopy (NIRS) for tissue oxygenation measurement has been developed for four decades. In recent years, a dynamic NIRS technology, namely, diffuse correlation spectroscopy (DCS), has been emerging as a portable tool for tissue blood flow measurement. In this article, we briefly describe the basic principle and algorithms for static NIRS and dynamic NIRS (i.e., DCS). Then, we elaborate on the NIRS instrumentation, either commercially available or custom-made, as well as their applications to physiological studies and clinic. The extension of NIRS/DCS from spectroscopy to imaging was depicted, followed by introductions of advanced algorithms that were recently proposed. The future prospective of the NIRS/DCS and their feasibilities for routine utilization in hospital is finally discussed.
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20
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Huang C, Gu Y, Chen J, Bahrani AA, Abu Jawdeh EG, Bada HS, Saatman K, Yu G, Chen L. A Wearable Fiberless Optical Sensor for Continuous Monitoring of Cerebral Blood Flow in Mice. IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS : A PUBLICATION OF THE IEEE LASERS AND ELECTRO-OPTICS SOCIETY 2019; 25:1-9. [PMID: 31666792 DOI: 10.1109/jstqe.2018.2869613] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Continuous and longitudinal monitoring of cerebral blood flow (CBF) in animal models provides information for studying the mechanisms and interventions of various cerebral diseases. Since anesthesia may affect brain hemodynamics, researchers have been seeking wearable devices for use in conscious animals. We present a wearable diffuse speckle contrast flowmeter (DSCF) probe for monitoring CBF variations in mice. The DSCF probe consists of a small low-power near-infrared laser diode as a point source and an ultra-small low-power CMOS camera as a 2D detector array, which can be affixed on a mouse head. The movement of red blood cells in brain cortex (i.e., CBF) produces spatial fluctuations of laser speckles, which are captured by the camera. The DSCF system was calibrated using tissue phantoms and validated in a human forearm and mouse brains for continuous monitoring of blood flow increases and decreases against the established technologies. Significant correlations were observed among these measurements (R2 ≥ 0.80, p < 10-5). This small fiberless probe has the potential to be worn by a freely moving conscious mouse. Moreover, the flexible source-detector configuration allows for varied probing depths up to ~8 mm, which is sufficient for transcranially detecting CBF in the cortices of rodents and newborn infants.
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Affiliation(s)
- Chong Huang
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY 40506 USA
| | - Yutong Gu
- Department of Electrical Engineering, University of Southern California, Los Angeles, CA, 90089 USA
| | - Jing Chen
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY 40506 USA
| | - Ahmed A Bahrani
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY 40506 USA
| | - Elie G Abu Jawdeh
- Department of Pediatrics, College of Medicine, University of Kentucky, Lexington, KY 40536 USA
| | - Henrietta S Bada
- Department of Pediatrics, College of Medicine, University of Kentucky, Lexington, KY 40536 USA
| | - Kathryn Saatman
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536 USA
| | - Guoqiang Yu
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY 40506 USA
| | - Lei Chen
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536 USA
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21
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Huang C, Gu Y, Chen J, Bahrani AA, Abu Jawdeh EG, Bada HS, Saatman K, Yu G, Chen L. A Wearable Fiberless Optical Sensor for Continuous Monitoring of Cerebral Blood Flow in Mice. IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS : A PUBLICATION OF THE IEEE LASERS AND ELECTRO-OPTICS SOCIETY 2019; 25:6900108. [PMID: 31666792 PMCID: PMC6821394 DOI: 10.1109/jstqe.2018.2854597] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Continuous and longitudinal monitoring of cerebral blood flow (CBF) in animal models provides information for studying the mechanisms and interventions of various cerebral diseases. Since anesthesia may affect brain hemodynamics, researchers have been seeking wearable devices for use in conscious animals. We present a wearable diffuse speckle contrast flowmeter (DSCF) probe for monitoring CBF variations in mice. The DSCF probe consists of a small low-power near-infrared laser diode as a point source and an ultra-small low-power CMOS camera as a 2D detector array, which can be affixed on a mouse head. The movement of red blood cells in brain cortex (i.e., CBF) produces spatial fluctuations of laser speckles, which are captured by the camera. The DSCF system was calibrated using tissue phantoms and validated in a human forearm and mouse brains for continuous monitoring of blood flow increases and decreases against the established technologies. Significant correlations were observed among these measurements (R2 ≥ 0.80, p < 10-5). This small fiberless probe has the potential to be worn by a freely moving conscious mouse. Moreover, the flexible source-detector configuration allows for varied probing depths up to ~8 mm, which is sufficient for transcranially detecting CBF in the cortices of rodents and newborn infants.
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Affiliation(s)
- Chong Huang
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY 40506 USA
| | - Yutong Gu
- Department of Electrical Engineering, University of Southern California, Los Angeles, CA, 90089 USA
| | - Jing Chen
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY 40506 USA
| | - Ahmed A. Bahrani
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY 40506 USA
| | - Elie G. Abu Jawdeh
- Department of Pediatrics, College of Medicine, University of Kentucky, Lexington, KY 40536 USA
| | - Henrietta S. Bada
- Department of Pediatrics, College of Medicine, University of Kentucky, Lexington, KY 40536 USA
| | - Kathryn Saatman
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536 USA
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22
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Zhang P, Gui Z, Guo G, Shang Y. Approaches to denoise the diffuse optical signals for tissue blood flow measurement. BIOMEDICAL OPTICS EXPRESS 2018; 9:6170-6185. [PMID: 31065421 PMCID: PMC6490982 DOI: 10.1364/boe.9.006170] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 10/21/2018] [Accepted: 10/26/2018] [Indexed: 05/03/2023]
Abstract
Various diseases are relevant to the abnormal blood flow in tissue. Diffuse correlation spectroscopy (DCS) is an emerging technology to extract the blood flow index (BFI) from light electric field temporal autocorrelation data. To account for tissue heterogeneity and irregular geometry, we developed an innovative DCS algorithm (i.e., the Nth order linear algorithm, or simply the NL algorithm) previously, in which the DCS signals are fully utilized through iterative linear regressions. Under the framework of NL algorithm, the BFI to be extracted is significantly influenced by the linear regression approach adopted. In this study, three approaches were proposed and evaluated for performing the iterative linear regressions, in order to understand what are the appropriate regression methods for BFI estimation. The three methods are least-squared minimization (L2 norm), least-absolute minimization (L1 norm) and support vector regression (SVR), where L2 norm is a conventional approach to perform linear regression. L1 norm and SVR are the approaches newly introduced here to process the DCS data. Computer simulations and the autocorrelation data collected from liquid phantom and human tissues are utilized to evaluate the three approaches. The results show that the best performance is achieved by the SVR approach in extracting the BFI values, with an error rate of 2.23% at 3.0 cm source-detector separation. The L1 norm method gives a medium error of 2.81%. In contrast, the L2 norm method leads to the largest error (3.93%) in extracting the BFI values. The outcomes derived from this study will be very helpful for the tissue blood flow measurements, which is critical for translating the DCS technology to the clinic.
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Affiliation(s)
- Peng Zhang
- Shanxi Provincial Key Laboratory for Biomedical Imaging and Big Data, North University of China, No. 3 Xueyuan Road, Taiyuan 030051, China
| | - Zhiguo Gui
- Shanxi Provincial Key Laboratory for Biomedical Imaging and Big Data, North University of China, No. 3 Xueyuan Road, Taiyuan 030051, China
| | - GuoDong Guo
- Shanxi Provincial Key Laboratory for Biomedical Imaging and Big Data, North University of China, No. 3 Xueyuan Road, Taiyuan 030051, China
- Department of Computer Science and Electrical Engineering, West Virginia University, Morgantown, WV26506, USA
| | - Yu Shang
- Shanxi Provincial Key Laboratory for Biomedical Imaging and Big Data, North University of China, No. 3 Xueyuan Road, Taiyuan 030051, China
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23
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Sathialingam E, Lee SY, Sanders B, Park J, McCracken CE, Bryan L, Buckley EM. Small separation diffuse correlation spectroscopy for measurement of cerebral blood flow in rodents. BIOMEDICAL OPTICS EXPRESS 2018; 9:5719-5734. [PMID: 30460158 PMCID: PMC6238900 DOI: 10.1364/boe.9.005719] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 10/15/2018] [Accepted: 10/16/2018] [Indexed: 05/11/2023]
Abstract
Diffuse correlation spectroscopy (DCS) has shown promise as a means to non-invasively measure cerebral blood flow in small animal models. Here, we characterize the validity of DCS at small source-detector reflectance separations needed for small animal measurements. Through Monte Carlo simulations and liquid phantom experiments, we show that DCS error increases as separation decreases, although error remains below 12% for separations > 0.2 cm. In mice, DCS measures of cerebral blood flow have excellent intra-user repeatability and strongly correlate with MRI measures of blood flow (R = 0.74, p<0.01). These results are generalizable to other DCS applications wherein short-separation reflectance geometries are desired.
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Affiliation(s)
- Eashani Sathialingam
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Dr. NE, Atlanta, GA 30322, USA
- co-first authorship
| | - Seung Yup Lee
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Dr. NE, Atlanta, GA 30322, USA
- co-first authorship
| | - Bharat Sanders
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Dr. NE, Atlanta, GA 30322, USA
| | - Jaekeun Park
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Dr. NE, Atlanta, GA 30322, USA
| | - Courtney E. McCracken
- Department of Pediatrics, School of Medicine, Emory University, 2015 Uppergate Dr., Atlanta, GA 30322, USA
| | - Leah Bryan
- Department of Pediatrics, School of Medicine, Emory University, 2015 Uppergate Dr., Atlanta, GA 30322, USA
| | - Erin M. Buckley
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Dr. NE, Atlanta, GA 30322, USA
- Department of Pediatrics, School of Medicine, Emory University, 2015 Uppergate Dr., Atlanta, GA 30322, USA
- Children’s Research Scholar, Children’s Healthcare of Atlanta, 2015 Uppergate Dr., Atlanta, GA 30322, USA
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24
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Bangalore-Yogananda CG, Rosenberry R, Soni S, Liu H, Nelson MD, Tian F. Concurrent measurement of skeletal muscle blood flow during exercise with diffuse correlation spectroscopy and Doppler ultrasound. BIOMEDICAL OPTICS EXPRESS 2018; 9:131-141. [PMID: 29359092 PMCID: PMC5772569 DOI: 10.1364/boe.9.000131] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 11/26/2017] [Accepted: 12/05/2017] [Indexed: 06/01/2023]
Abstract
Noninvasive, direct measurement of local muscle blood flow in humans remains limited. Diffuse correlation spectroscopy (DCS) is an emerging technique to measure regional blood flow at the microvascular level. In order to better understand the strengths and limitations of this novel technique, we performed a validation study by comparing muscle blood flow changes measured with DCS and Doppler ultrasound during exercise. Nine subjects were measured (all males, 27.4 ± 2.9 years of age) for a rhythmic handgrip exercise at 20% and 50% of individual maximum voluntary contraction (MVC), followed by a post-exercise recovery. The results from DCS and Doppler ultrasound were highly correlated (R = 0.99 ± 0.02). DCS was more reliable and less susceptible to motion artifact.
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Affiliation(s)
- Chandan-Ganesh Bangalore-Yogananda
- Department of Bioengineering, The University of Texas at Arlington, 500 UTA Blvd., Arlington, TX 76010, USA
- Two authors contributed equally
| | - Ryan Rosenberry
- Department of Kinesiology, The University of Texas at Arlington, 411 S. Nedderman Dr., Arlington, TX 76010, USA
- Two authors contributed equally
| | - Sagar Soni
- Department of Bioengineering, The University of Texas at Arlington, 500 UTA Blvd., Arlington, TX 76010, USA
| | - Hanli Liu
- Department of Bioengineering, The University of Texas at Arlington, 500 UTA Blvd., Arlington, TX 76010, USA
| | - Michael D. Nelson
- Department of Bioengineering, The University of Texas at Arlington, 500 UTA Blvd., Arlington, TX 76010, USA
- Department of Kinesiology, The University of Texas at Arlington, 411 S. Nedderman Dr., Arlington, TX 76010, USA
| | - Fenghua Tian
- Department of Bioengineering, The University of Texas at Arlington, 500 UTA Blvd., Arlington, TX 76010, USA
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25
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Blanco I, Zirak P, Dragojević T, Castellvi C, Durduran T, Justicia C. Longitudinal, transcranial measurement of functional activation in the rat brain by diffuse correlation spectroscopy. NEUROPHOTONICS 2017; 4:045006. [PMID: 29226175 PMCID: PMC5715584 DOI: 10.1117/1.nph.4.4.045006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 11/09/2017] [Indexed: 05/16/2023]
Abstract
Neural activity is an important biomarker for the presence of neurodegenerative diseases, cerebrovascular alterations, and brain trauma; furthermore, it is a surrogate marker for treatment effects. These pathologies may occur and evolve in a long time-period, thus, noninvasive, transcutaneous techniques are necessary to allow a longitudinal follow-up. In the present work, we have customized noninvasive, transcutaneous, diffuse correlation spectroscopy (DCS) to localize changes in cerebral blood flow (CBF) induced by neural activity. We were able to detect changes in CBF in the somatosensory cortex by using a model of electrical forepaw stimulation in rats. The suitability of DCS measurements for longitudinal monitoring was demonstrated by performing multiple sessions with the same animals at different ages (from 6 to 18 months). In addition, functional DCS has been cross-validated by comparison with functional magnetic resonance imaging (fMRI) in the same animals in a subset of the time-points. The overall results obtained with transcutaneous DCS demonstrates that it can be utilized in longitudinal studies safely and reproducibly to locate changes in CBF induced by neural activity in the small animal brain.
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Affiliation(s)
- Igor Blanco
- ICFO-Institut de Ciències Fotòniques, Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
- Address all correspondence to: Igor Blanco, E-mail:
| | - Peyman Zirak
- ICFO-Institut de Ciències Fotòniques, Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
| | - Tanja Dragojević
- ICFO-Institut de Ciències Fotòniques, Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
| | - Clara Castellvi
- Insitut d’Investigacions Biomèdiques de Barcelona (IIBB), Consejo Superior de Investigaciones Científicas (CSIC), Department of Brain Ischemia and Neurodegeneration, Barcelona, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Àrea de Neurociències, Barcelona, Spain
| | - Turgut Durduran
- ICFO-Institut de Ciències Fotòniques, Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Carles Justicia
- Insitut d’Investigacions Biomèdiques de Barcelona (IIBB), Consejo Superior de Investigaciones Científicas (CSIC), Department of Brain Ischemia and Neurodegeneration, Barcelona, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Àrea de Neurociències, Barcelona, Spain
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26
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Yazdi HS, O’Sullivan TD, Leproux A, Hill B, Durkin A, Telep S, Lam J, Yazdi SS, Police AM, Carroll RM, Combs FJ, Strömberg T, Yodh AG, Tromberg BJ. Mapping breast cancer blood flow index, composition, and metabolism in a human subject using combined diffuse optical spectroscopic imaging and diffuse correlation spectroscopy. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:45003. [PMID: 28384703 PMCID: PMC5381696 DOI: 10.1117/1.jbo.22.4.045003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 03/13/2017] [Indexed: 05/18/2023]
Abstract
Diffuse optical spectroscopic imaging (DOSI) and diffuse correlation spectroscopy (DCS) are model-based near-infrared (NIR) methods that measure tissue optical properties (broadband absorption, ? a , and reduced scattering, ? s ? ) and blood flow (blood flow index, BFI), respectively. DOSI-derived ? a values are used to determine composition by calculating the tissue concentration of oxy- and deoxyhemoglobin ( HbO 2 , HbR), water, and lipid. We developed and evaluated a combined, coregistered DOSI/DCS handheld probe for mapping and imaging these parameters. We show that uncertainties of 0.3 ?? mm ? 1 (37%) in ? s ? and 0.003 ?? mm ? 1 (33%) in ? a lead to ? 53 % and 9% errors in BFI, respectively. DOSI/DCS imaging of a solid tissue-simulating flow phantom and
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MESH Headings
- Adult
- Carcinoma, Ductal, Breast/blood supply
- Carcinoma, Ductal, Breast/diagnostic imaging
- Carcinoma, Ductal, Breast/drug therapy
- Diffusion
- Female
- Hemoglobins/analysis
- Humans
- Lipids/blood
- Models, Theoretical
- Neoadjuvant Therapy
- Oxyhemoglobins/analysis
- Phantoms, Imaging
- Spectrophotometry/methods
- Spectroscopy, Near-Infrared/methods
- Tomography, Optical/methods
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Affiliation(s)
- Hossein S. Yazdi
- University of California, Beckman Laser Institute and Medical Clinic, Irvine, California, United States
| | - Thomas D. O’Sullivan
- University of California, Beckman Laser Institute and Medical Clinic, Irvine, California, United States
| | - Anais Leproux
- University of California, Beckman Laser Institute and Medical Clinic, Irvine, California, United States
| | - Brian Hill
- University of California, Beckman Laser Institute and Medical Clinic, Irvine, California, United States
| | - Amanda Durkin
- University of California, Beckman Laser Institute and Medical Clinic, Irvine, California, United States
| | - Seraphim Telep
- University of California, Beckman Laser Institute and Medical Clinic, Irvine, California, United States
| | - Jesse Lam
- University of California, Beckman Laser Institute and Medical Clinic, Irvine, California, United States
| | - Siavash S. Yazdi
- University of California, Beckman Laser Institute and Medical Clinic, Irvine, California, United States
| | - Alice M. Police
- University of California, Chao Family Comprehensive Cancer Center, Orange, California, United States
| | - Robert M. Carroll
- University of California, Chao Family Comprehensive Cancer Center, Orange, California, United States
| | - Freddie J. Combs
- University of California, Chao Family Comprehensive Cancer Center, Orange, California, United States
| | - Tomas Strömberg
- University of California, Beckman Laser Institute and Medical Clinic, Irvine, California, United States
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
| | - Arjun G. Yodh
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
| | - Bruce J. Tromberg
- University of California, Beckman Laser Institute and Medical Clinic, Irvine, California, United States
- Address all correspondence to: Bruce J. Tromberg, E-mail:
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27
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Shang Y, Li T, Yu G. Clinical applications of near-infrared diffuse correlation spectroscopy and tomography for tissue blood flow monitoring and imaging. Physiol Meas 2017; 38:R1-R26. [PMID: 28199219 PMCID: PMC5726862 DOI: 10.1088/1361-6579/aa60b7] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Blood flow is one such available observable promoting a wealth of physiological insight both individually and in combination with other metrics. APPROACH Near-infrared diffuse correlation spectroscopy (DCS) and, to a lesser extent, diffuse correlation tomography (DCT), have increasingly received interest over the past decade as noninvasive methods for tissue blood flow measurements and imaging. DCS/DCT offers several attractive features for tissue blood flow measurements/imaging such as noninvasiveness, portability, high temporal resolution, and relatively large penetration depth (up to several centimeters). MAIN RESULTS This review first introduces the basic principle and instrumentation of DCS/DCT, followed by presenting clinical application examples of DCS/DCT for the diagnosis and therapeutic monitoring of diseases in a variety of organs/tissues including brain, skeletal muscle, and tumor. SIGNIFICANCE Clinical study results demonstrate technical versatility of DCS/DCT in providing important information for disease diagnosis and intervention monitoring.
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Affiliation(s)
- Yu Shang
- Key Laboratory of Instrumentation Science & Dynamic Measurement, North University of China, No.3 Xueyuan Road, Taiyuan, Shanxi 030051, China
| | - Ting Li
- State Key Lab Elect Thin Film & Integrated Device, University of Electronic Science & Technology of China, Chengdu, Sichuan 610054, China
| | - Guoqiang Yu
- Department of Biomedical Engineering, University of Kentucky, 514C RMB, 143 Graham Avenue, Lexington, KY 40506-0108, USA
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28
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Seong M, Phillips Z, Mai PM, Yeo C, Song C, Lee K, Kim JG. Simultaneous blood flow and blood oxygenation measurements using a combination of diffuse speckle contrast analysis and near-infrared spectroscopy. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:27001. [PMID: 26886805 DOI: 10.1117/1.jbo.21.2.027001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 01/21/2016] [Indexed: 05/03/2023]
Abstract
A combined diffuse speckle contrast analysis (DSCA)-near-infrared spectroscopy (NIRS) system is proposed to simultaneously measure qualitative blood flow and blood oxygenation changes in human tissue. The system employs an optical switch to alternate two laser sources at two different wavelengths and a CCD camera to capture the speckle image. Therefore, an optical density can be measured from two wavelengths for NIRS measurements and a speckle contrast can be calculated for DSCA measurements. In order to validate the system, a flow phantom test and an arm occlusion protocol for arterial and venous occlusion were performed. Shorter exposure times (<1 ms ) show a higher drop (between 50% and 66%) and recovery of 1/K²S values after occlusion (approximately 150%), but longer exposure time (3 ms) shows more consistent hemodynamic changes. For four subjects, the 1/K²S values dropped to an average of 82.1±4.0% during the occlusion period and the average recovery of 1/K²S values after occlusion was 109.1±0.8% . There was also an approximately equivalent amplitude change in oxyhemoglobin (OHb) and deoxyhemoglobin (RHb) during arterial occlusion (max RHb=0.0085±0.0024 mM/DPF, min OHb=-0.0057±0.0044 mM/DPF). The sensitivity of the system makes it a suitable modality to observe qualitative hemodynamic trends during induced physiological changes.
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Affiliation(s)
- Myeongsu Seong
- Gwangju Institute of Science and Technology, Department of Medical System Engineering, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Zephaniah Phillips
- Gwangju Institute of Science and Technology, School of Information and Communications, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Phuong Minh Mai
- Gwangju Institute of Science and Technology, School of Information and Communications, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea
| | - Chaebeom Yeo
- Daegu Gyeongbuk Institute of Science and Technology, Department of Robotic Engineering, 333 Techno Jungang-Daero, Hyeongpung-myeon, Dalseong-gun, Daegu 42988, Republic of Korea
| | - Cheol Song
- Daegu Gyeongbuk Institute of Science and Technology, Department of Robotic Engineering, 333 Techno Jungang-Daero, Hyeongpung-myeon, Dalseong-gun, Daegu 42988, Republic of Korea
| | - Kijoon Lee
- Daegu Gyeongbuk Institute of Science and Technology, School of Basic Sciences, 333 Techno Jungang-Daero, Hyeongpung-myeon, Dalseong-gun, Daegu 42988, Republic of Korea
| | - Jae Gwan Kim
- Gwangju Institute of Science and Technology, Department of Medical System Engineering, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of KoreabGwangju Institute of Science and Technology, School of Information and Communications, 123 Cheomdangwagi-
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29
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Baker WB, Parthasarathy AB, Busch DR, Mesquita RC, Greenberg JH, Yodh AG. Modified Beer-Lambert law for blood flow. BIOMEDICAL OPTICS EXPRESS 2014; 5:4053-75. [PMID: 25426330 PMCID: PMC4242038 DOI: 10.1364/boe.5.004053] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 10/14/2014] [Accepted: 10/15/2014] [Indexed: 05/18/2023]
Abstract
We develop and validate a Modified Beer-Lambert law for blood flow based on diffuse correlation spectroscopy (DCS) measurements. The new formulation enables blood flow monitoring from temporal intensity autocorrelation function data taken at single or multiple delay-times. Consequentially, the speed of the optical blood flow measurement can be substantially increased. The scheme facilitates blood flow monitoring of highly scattering tissues in geometries wherein light propagation is diffusive or non-diffusive, and it is particularly well-suited for utilization with pressure measurement paradigms that employ differential flow signals to reduce contributions of superficial tissues.
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Affiliation(s)
- Wesley B. Baker
- Dept. Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104,
USA
| | | | - David R. Busch
- Dept. Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104,
USA
- Div. of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA 19104,
USA
| | - Rickson C. Mesquita
- Institute of Physics, University of Campinas, Campinas, SP 13083-859,
Brazil
| | - Joel H. Greenberg
- Dept. Neurology, University of Pennsylvania, Philadelphia, PA 19104,
USA
| | - A. G. Yodh
- Dept. Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104,
USA
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30
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Shang Y, Yu G. A Nth-order linear algorithm for extracting diffuse correlation spectroscopy blood flow indices in heterogeneous tissues. APPLIED PHYSICS LETTERS 2014; 105:133702. [PMID: 25378708 PMCID: PMC4214282 DOI: 10.1063/1.4896992] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 09/15/2014] [Indexed: 05/19/2023]
Abstract
Conventional semi-infinite analytical solutions of correlation diffusion equation may lead to errors when calculating blood flow index (BFI) from diffuse correlation spectroscopy (DCS) measurements in tissues with irregular geometries. Very recently, we created an algorithm integrating a Nth-order linear model of autocorrelation function with the Monte Carlo simulation of photon migrations in homogenous tissues with arbitrary geometries for extraction of BFI (i.e., αDB ). The purpose of this study is to extend the capability of the Nth-order linear algorithm for extracting BFI in heterogeneous tissues with arbitrary geometries. The previous linear algorithm was modified to extract BFIs in different types of tissues simultaneously through utilizing DCS data at multiple source-detector separations. We compared the proposed linear algorithm with the semi-infinite homogenous solution in a computer model of adult head with heterogeneous tissue layers of scalp, skull, cerebrospinal fluid, and brain. To test the capability of the linear algorithm for extracting relative changes of cerebral blood flow (rCBF) in deep brain, we assigned ten levels of αDB in the brain layer with a step decrement of 10% while maintaining αDB values constant in other layers. Simulation results demonstrate the accuracy (errors < 3%) of high-order (N ≥ 5) linear algorithm in extracting BFIs in different tissue layers and rCBF in deep brain. By contrast, the semi-infinite homogenous solution resulted in substantial errors in rCBF (34.5% ≤ errors ≤ 60.2%) and BFIs in different layers. The Nth-order linear model simplifies data analysis, thus allowing for online data processing and displaying. Future study will test this linear algorithm in heterogeneous tissues with different levels of blood flow variations and noises.
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Affiliation(s)
- Yu Shang
- Department of Biomedical Engineering, University of Kentucky , Lexington, Kentucky 40506, USA
| | - Guoqiang Yu
- Department of Biomedical Engineering, University of Kentucky , Lexington, Kentucky 40506, USA
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31
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Hou Y, Shang Y, Cheng R, Zhao Y, Qin Y, Kryscio R, Rayapati A, Hayes D, Yu G. Obstructive sleep apnea-hypopnea results in significant variations in cerebral hemodynamics detected by diffuse optical spectroscopies. Physiol Meas 2014; 35:2135-48. [PMID: 25243760 DOI: 10.1088/0967-3334/35/10/2135] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The objective of this study was to adapt a novel near-infrared diffuse correlation spectroscopy (DCS) flow-oximeter for simultaneous and continuous monitoring of relative changes in cerebral blood flow (rCBF) and cerebral oxygenation (i.e. oxygenated/deoxygenated/total hemoglobin concentration: Δ[HbO2]/Δ[Hb]/ΔTHC) during overnight nocturnal polysomnography (NPSG) diagnostic test for obstructive sleep apnea-hypopnea (OSAH). A fiber-optic probe was fixed on subject's frontal head and connected to the DCS flow-oximeter through a custom-designed fiber-optic connector, which allowed us to easily connect/detach the optical probe from the device when the subject went to bathroom. To minimize the disturbance to the subject, the DCS flow-oximeter was remotely operated by a desktop located in the control room. The results showed that apneic events caused significant variations in rCBF and ΔTHC. Moreover, the degrees of variations in all measured cerebral variables were significantly correlated with the severity of OSAH as determined by the apnea-hypopnea index (AHI), demonstrating the OSAH influence on both CBF and cerebral oxygenation. Large variations in arterial blood oxygen saturation (SaO2) were also found during OSAH. Since frequent variations/disturbances in cerebral hemodynamics may adversely impact brain function, future study will investigate the correlations between these cerebral variations and functional impairments for better understanding of OSAH pathophysiology.
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Affiliation(s)
- Yajun Hou
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY 40506, USA. College of Science, Shenyang Ligong University, Shenyang, Liaoning 110159, People's Republic of China
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32
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Buckley EM, Parthasarathy AB, Grant PE, Yodh AG, Franceschini MA. Diffuse correlation spectroscopy for measurement of cerebral blood flow: future prospects. NEUROPHOTONICS 2014; 1:011009. [PMID: 25593978 PMCID: PMC4292799 DOI: 10.1117/1.nph.1.1.011009] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Diffuse correlation spectroscopy (DCS) is an emerging optical modality used to measure cortical cerebral blood flow. This outlook presents a brief overview of the technology, summarizing the advantages and limitations of the method, and describing its recent applications to animal, adult, and infant cohorts. At last, the paper highlights future applications where DCS may play a pivotal role individualizing patient management and enhancing our understanding of neurovascular coupling, activation, and brain development.
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Affiliation(s)
- Erin M. Buckley
- Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts 02129
- Address all correspondence to: Erin M. Buckley,
| | - Ashwin B. Parthasarathy
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania 19104
| | - P. Ellen Grant
- Boston Children’s Hospital, Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston, Massachusetts 02115
| | - Arjun G. Yodh
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania 19104
| | - Maria Angela Franceschini
- Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts 02129
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33
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Shang Y, Li T, Chen L, Lin Y, Toborek M, Yu G. Extraction of diffuse correlation spectroscopy flow index by integration of Nth-order linear model with Monte Carlo simulation. APPLIED PHYSICS LETTERS 2014; 104:193703. [PMID: 24926099 PMCID: PMC4032444 DOI: 10.1063/1.4876216] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 04/30/2014] [Indexed: 05/19/2023]
Abstract
Conventional semi-infinite solution for extracting blood flow index (BFI) from diffuse correlation spectroscopy (DCS) measurements may cause errors in estimation of BFI (αDB ) in tissues with small volume and large curvature. We proposed an algorithm integrating Nth-order linear model of autocorrelation function with the Monte Carlo simulation of photon migrations in tissue for the extraction of αDB . The volume and geometry of the measured tissue were incorporated in the Monte Carlo simulation, which overcome the semi-infinite restrictions. The algorithm was tested using computer simulations on four tissue models with varied volumes/geometries and applied on an in vivo stroke model of mouse. Computer simulations shows that the high-order (N ≥ 5) linear algorithm was more accurate in extracting αDB (errors < ±2%) from the noise-free DCS data than the semi-infinite solution (errors: -5.3% to -18.0%) for different tissue models. Although adding random noises to DCS data resulted in αDB variations, the mean values of errors in extracting αDB were similar to those reconstructed from the noise-free DCS data. In addition, the errors in extracting the relative changes of αDB using both linear algorithm and semi-infinite solution were fairly small (errors < ±2.0%) and did not rely on the tissue volume/geometry. The experimental results from the in vivo stroke mice agreed with those in simulations, demonstrating the robustness of the linear algorithm. DCS with the high-order linear algorithm shows the potential for the inter-subject comparison and longitudinal monitoring of absolute BFI in a variety of tissues/organs with different volumes/geometries.
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Affiliation(s)
- Yu Shang
- Department of Biomedical Engineering, University of Kentucky, Lexington, Kentucky 40506, USA
| | - Ting Li
- Department of Biomedical Engineering, University of Kentucky, Lexington, Kentucky 40506, USA ; State Key Laboratory for Electronic Thin Film and Integrated Device, University of Electronic Science and Technology of China, Chengdu 610054, People's Republic of China
| | - Lei Chen
- Department of Neurosurgery, University of Kentucky, Lexington, Kentucky 40536, USA
| | - Yu Lin
- Department of Biomedical Engineering, University of Kentucky, Lexington, Kentucky 40506, USA
| | - Michal Toborek
- Department of Neurosurgery, University of Kentucky, Lexington, Kentucky 40536, USA
| | - Guoqiang Yu
- Department of Biomedical Engineering, University of Kentucky, Lexington, Kentucky 40506, USA
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Zhang X, Cheng R, Rowe D, Sethu P, Daugherty A, Yu G, Shin HY. Shear-sensitive regulation of neutrophil flow behavior and its potential impact on microvascular blood flow dysregulation in hypercholesterolemia. Arterioscler Thromb Vasc Biol 2014; 34:587-93. [PMID: 24458712 DOI: 10.1161/atvbaha.113.302868] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Shear stress-induced pseudopod retraction is an anti-inflammatory measure that minimizes neutrophil activity and is regulated by membrane cholesterol. We tested the hypothesis that a hypercholesterolemic impairment of shear mechanotransduction alters the neutrophil flow behavior leading to microvascular dysfunction. APPROACH AND RESULTS We examined the shear effects on the flow behavior of human leukocytes. When subjected to shearing during cone-plate viscometry, leukocyte suspensions exhibited parallel time-dependent reductions in viscosity and pseudopod activity. Shear-induced reductions in suspension viscosity were attenuated by membrane cholesterol enrichment. We also showed that enhanced pseudopod activity of leukocyte suspensions in 10% hematocrit significantly (P<0.05) raised the flow resistance of microvascular mimics. These results implicate an impaired neutrophil pseudopod retraction response to shear in hypercholesterolemic microvascular dysfunction. We confirmed this using near-infrared diffuse correlation spectroscopy to assess skeletal muscle blood flow regulation in the hindlimbs of mice subjected to reactive hyperemia. Using a custom protocol for the mouse, we extrapolated an adjusted peak flow and time to adjusted peak flow to quantify the early phase of the blood flow recovery response during reactive hyperemia when shear mechanobiology likely has a maximal impact. Compared with mice on normal diet, hypercholesterolemic mice exhibited significantly (P<0.05) reduced adjusted peak flow and prolonged time to adjusted peak flow which correlated (r=0.4 and r=-0.3, respectively) with neutrophil shear responsiveness and were abrogated by neutropenia. CONCLUSIONS These results provide the first evidence that the neutrophils contribute to tissue blood flow autoregulation. Moreover, a deficit in the neutrophil responsiveness to shear may be a feature of hypercholesterolemia-related microvascular dysfunction.
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Affiliation(s)
- Xiaoyan Zhang
- From the Department of Biomedical Engineering, University of Kentucky, Lexington (X.Z., R.C., D.R., G.Y., H.Y.S); Math, Science, and Technology Center, Paul L. Dunbar High School, Lexington, KY (D.R.); Division of Cardiovascular Disease, University of Alabama at Birmingham (P.S.); and Saha Cardiovascular Research Center, University of Kentucky, Lexington (A.D.)
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35
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Durduran T, Yodh AG. Diffuse correlation spectroscopy for non-invasive, micro-vascular cerebral blood flow measurement. Neuroimage 2014; 85 Pt 1:51-63. [PMID: 23770408 PMCID: PMC3991554 DOI: 10.1016/j.neuroimage.2013.06.017] [Citation(s) in RCA: 289] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 05/10/2013] [Accepted: 06/06/2013] [Indexed: 12/25/2022] Open
Abstract
Diffuse correlation spectroscopy (DCS) uses the temporal fluctuations of near-infrared (NIR) light to measure cerebral blood flow (CBF) non-invasively. Here, we provide a brief history of DCS applications in the brain with an emphasis on the underlying physical ideas, common instrumentation and validation. Then we describe recent clinical research that employs DCS-measured CBF as a biomarker of patient well-being, and as an indicator of hemodynamic and metabolic responses to functional stimuli.
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Affiliation(s)
- Turgut Durduran
- ICFO- Institut de Ciències Fotòniques, Mediterranean Technology Park, 08860 Castelldefels, Barcelona, Spain.
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Cheng R, Shang Y, Wang S, Evans JM, Rayapati A, Randall DC, Yu G. Near-infrared diffuse optical monitoring of cerebral blood flow and oxygenation for the prediction of vasovagal syncope. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:17001. [PMID: 24402372 PMCID: PMC3884846 DOI: 10.1117/1.jbo.19.1.017001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 12/01/2013] [Accepted: 12/10/2013] [Indexed: 05/21/2023]
Abstract
Significant drops in arterial blood pressure and cerebral hemodynamics have been previously observed during vasovagal syncope (VVS). Continuous and simultaneous monitoring of these physiological variables during VVS is rare, but critical for determining which variable is the most sensitive parameter to predict VVS. The present study used a novel custom-designed diffuse correlation spectroscopy flow-oximeter and a finger plethysmograph to simultaneously monitor relative changes of cerebral blood flow (rCBF), cerebral oxygenation (i.e., oxygenated/deoxygenated/total hemoglobin concentration: r[HbO2]/r[Hb]/rTHC), and mean arterial pressure (rMAP) during 70 deg head-up tilt (HUT) in 14 healthy adults. Six subjects developed presyncope during HUT. Two-stage physiological responses during HUT were observed in the presyncopal group: slow and small changes in measured variables (i.e., Stage I), followed by rapid and dramatic decreases in rMAP, rCBF, r[HbO2], and rTHC (i.e., Stage II). Compared to other physiological variables, rCBF reached its breakpoint between the two stages earliest and had the largest decrease (76±8%) during presyncope. Our results suggest that rCBF has the best sensitivity for the assessment of VVS. Most importantly, a threshold of ∼50% rCBF decline completely separated the subjects from those without presyncope, suggesting its potential for predicting VVS.
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Affiliation(s)
- Ran Cheng
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
| | - Yu Shang
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
| | - Siqi Wang
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
| | - Joyce M. Evans
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
| | - Abner Rayapati
- University of Kentucky, Department of Psychiatry, Lexington, Kentucky 40509
| | - David C. Randall
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
- University of Kentucky, Department of Physiology, Lexington, Kentucky 40536
| | - Guoqiang Yu
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
- Address all correspondence to: Guoqiang Yu, E-mail:
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Bink DI, Ritz K, Aronica E, van der Weerd L, Daemen MJAP. Mouse models to study the effect of cardiovascular risk factors on brain structure and cognition. J Cereb Blood Flow Metab 2013; 33:1666-84. [PMID: 23963364 PMCID: PMC3824184 DOI: 10.1038/jcbfm.2013.140] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 06/24/2013] [Accepted: 07/16/2013] [Indexed: 12/13/2022]
Abstract
Recent clinical data indicates that hemodynamic changes caused by cardiovascular diseases such as atherosclerosis, heart failure, and hypertension affect cognition. Yet, the underlying mechanisms of the resulting vascular cognitive impairment (VCI) are poorly understood. One reason for the lack of mechanistic insights in VCI is that research in dementia primarily focused on Alzheimer's disease models. To fill in this gap, we critically reviewed the published data and various models of VCI. Typical findings in VCI include reduced cerebral perfusion, blood-brain barrier alterations, white matter lesions, and cognitive deficits, which have also been reported in different cardiovascular mouse models. However, the tests performed are incomplete and differ between models, hampering a direct comparison between models and studies. Nevertheless, from the currently available data we conclude that a few existing surgical animal models show the key features of vascular cognitive decline, with the bilateral common carotid artery stenosis hypoperfusion mouse model as the most promising model. The transverse aortic constriction and myocardial infarction models may be good alternatives, but these models are as yet less characterized regarding the possible cerebral changes. Mixed models could be used to study the combined effects of different cardiovascular diseases on the deterioration of cognition during aging.
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Affiliation(s)
- Diewertje I Bink
- Department of Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Katja Ritz
- Department of Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Eleonora Aronica
- Department of Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- SEIN—Stichting Epilepsie Instellingen Nederland, Heemstede, The Netherlands
- Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands
| | - Louise van der Weerd
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Mat JAP Daemen
- Department of Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Cheng R, Zhang X, Daugherty A, Shin H, Yu G. Noninvasive quantification of postocclusive reactive hyperemia in mouse thigh muscle by near-infrared diffuse correlation spectroscopy. APPLIED OPTICS 2013; 52:7324-30. [PMID: 24216586 DOI: 10.1364/ao.52.007324] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Many vasculature-related diseases affecting skeletal muscle function have been studied in mouse models. Noninvasive quantification of muscle blood flow responses during postocclusive reactive hyperemia (PORH) is often used to evaluate vascular function in human skeletal muscles. However, blood flow measurements during PORH in small skeletal muscles of mice are rare due to the lack of appropriate technologies coupled with the challenge of measurement setup resulting from the lack of large enough test sites. In this study, we explored adapting diffuse correlation spectroscopy (DCS) for noninvasive measurement of the relative changes of blood flow (rBF) in mouse thigh muscles during PORH. A small fiber-optic probe was designed and glued on the mouse thigh to reduce the motion artifact induced by the occlusion procedure. Arterial occlusion was created by tying a polyvinyl chloride (PVC) tube around the mouse thigh while the muscle rBF was continuously monitored by DCS to ensure the success of the occlusion. After 5 min, the occlusion was rapidly released by severing the PVC tube using a cautery pen. Typical rBF responses during PORH were observed in all mice (n=7), which are consistent with those observed by arterial-spin-labeled magnetic resonance imaging (ASL-MRI) as reported in the literature. On average, rBF values from DCS during occlusion were lower than 10% (3.1±2.2%) of the baseline values (assigning 100%), indicating the success of arterial occlusion in all mice. Peak values of rBF during PORH measured by the DCS (357.6±36.3%) and ASL-MRI (387.5±150.0%) were also similar whereas the values of time-to-peak (the time duration from the end of occlusion to the peak rBF) were quite different (112.6±35.0 s versus 48.0±27.0 s). Simultaneous measurements by these two techniques are needed to identify the factors that may cause such discrepancy. This study highlights the utility of DCS technology to quantitatively evaluate tissue blood flow responses during PORH in mouse skeletal muscles. DCS holds promise as valuable tool to assess blood flow regulation in mouse models with a variety of vascular diseases (e.g., hypercholesterolemia, diabetes, peripheral artery disease).
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Shang Y, Lin Y, Henry BA, Cheng R, Huang C, Chen L, Shelton BJ, Swartz KR, Salles SS, Yu G. Noninvasive evaluation of electrical stimulation impacts on muscle hemodynamics via integrating diffuse optical spectroscopies with muscle stimulator. JOURNAL OF BIOMEDICAL OPTICS 2013; 18:105002. [PMID: 24096298 PMCID: PMC3790391 DOI: 10.1117/1.jbo.18.10.105002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 09/04/2013] [Indexed: 05/03/2023]
Abstract
Technologies currently available for the monitoring of electrical stimulation (ES) in promoting blood circulation and tissue oxygenation are limited. This study integrated a muscle stimulator with a diffuse correlation spectroscopy (DCS) flow-oximeter to noninvasively quantify muscle blood flow and oxygenation responses during ES. Ten healthy subjects were tested using the integrated system. The muscle stimulator delivered biphasic electrical current to right leg quadriceps muscle, and a custom-made DCS flow-oximeter was used for simultaneous measurements of muscle blood flow and oxygenation in both legs. To minimize motion artifact of muscle fibers during ES, a novel gating algorithm was developed for data acquisition at the time when the muscle was relaxed. ES at 2, 10, and 50 Hz were applied for 20 min on each subject in three days sequentially. Results demonstrate that the 20-min ES at all frequencies promoted muscle blood flow significantly. However, only the ES at 10 Hz resulted in significant and persistent increases in oxy-hemoglobin concentration during and post ES. This pilot study supports the application of the integrated system to quantify tissue hemodynamic improvements for the optimization of ES treatment in patients suffering from diseases caused by poor blood circulation and low tissue oxygenation (e.g., pressure ulcer).
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Affiliation(s)
- Yu Shang
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
| | - Yu Lin
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
| | - Brad A. Henry
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
| | - Ran Cheng
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
| | - Chong Huang
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
| | - Li Chen
- University of Kentucky, Department of Biostatistics, Lexington, Kentucky 40536
| | - Brent J. Shelton
- University of Kentucky, Department of Biostatistics, Lexington, Kentucky 40536
| | - Karin R. Swartz
- University of Kentucky, Department of Neurosurgery, Lexington, Kentucky 40536
| | - Sara S. Salles
- University of Kentucky, Department of Physical Medicine and Rehabilitation, Lexington, Kentucky 40536
| | - Guoqiang Yu
- University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506
- Address all correspondence to: Guoqiang Yu, University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky 40506. Tel: 859-257-9110; Fax: 859-257-1856; E-mail:
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Simultaneous measurement of deep tissue blood flow and oxygenation using noncontact diffuse correlation spectroscopy flow-oximeter. Sci Rep 2013; 3:1358. [PMID: 23446991 PMCID: PMC3584314 DOI: 10.1038/srep01358] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 02/14/2013] [Indexed: 01/10/2023] Open
Abstract
We report a novel noncontact diffuse correlation spectroscopy flow-oximeter for simultaneous quantification of relative changes in tissue blood flow (rBF) and oxygenation (Δ[oxygenation]). The noncontact probe was compared against a contact probe in tissue-like phantoms and forearm muscles (n = 10), and the dynamic trends in both rBF and Δ[oxygenation] were found to be highly correlated. However, the magnitudes of Δ[oxygenation] measured by the two probes were significantly different. Monte Carlo simulations and phantom experiments revealed that the arm curvature resulted in a significant underestimation (~−20%) for the noncontact measurements in Δ[oxygenation], but not in rBF. Other factors that may cause the residual discrepancies between the contact and noncontact measurements were discussed, and further comparisons with other established technologies are needed to identify/quantify these factors. Our research paves the way for noncontact and simultaneous monitoring of blood flow and oxygenation in soft and vulnerable tissues without distorting tissue hemodynamics.
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Lin ZJ, Ren M, Li L, Liu Y, Su J, Yang SH, Liu H. Interleaved imaging of cerebral hemodynamics and blood flow index to monitor ischemic stroke and treatment in rat by volumetric diffuse optical tomography. Neuroimage 2013; 85 Pt 1:566-82. [PMID: 23872158 DOI: 10.1016/j.neuroimage.2013.07.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 07/05/2013] [Accepted: 07/06/2013] [Indexed: 12/29/2022] Open
Abstract
Diffuse optical tomography (DOT) has been used by several groups to assess cerebral hemodynamics of cerebral ischemia in humans and animals. In this study, we combined DOT with an indocyanine green (ICG)-tracking method to achieve interleaved images of cerebral hemodynamics and blood flow index (BFI) using two middle cerebral artery occlusion (MCAO) rat models. To achieve volumetric images with high-spatial resolution, we first integrated a depth compensation algorithm (DCA) with a volumetric mesh-based rat head model to generate three-dimensional (3D) DOT on a rat brain atlas. Then, the experimental DOT data from two rat models were collected using interleaved strategy for cerebral hemodynamics and BFI during and after ischemic stroke, with and without a thrombolytic therapy for the embolic MCAO model. The acquired animal data were further analyzed using the integrated rat-atlas-guided DOT method to form time-evolving 3D images of both cerebral hemodynamics and BFI. In particular, we were able to show and identify therapeutic outcomes of a thrombolytic treatment applied to the embolism-induced ischemic model. This paper demonstrates that volumetric DOT is capable of providing high-quality, interleaved images of cerebral hemodynamics and blood perfusion in small animals during and after ischemic stroke, with excellent 3D visualization and quantifications.
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Affiliation(s)
- Zi-Jing Lin
- Department of Bioengineering, Joint Graduate Program between University of Texas at Arlington and University of Texas Southwestern Medical Center, University of Texas at Arlington, TX 76019, USA
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He L, Lin Y, Shang Y, Shelton BJ, Yu G. Using optical fibers with different modes to improve the signal-to-noise ratio of diffuse correlation spectroscopy flow-oximeter measurements. JOURNAL OF BIOMEDICAL OPTICS 2013; 18:037001. [PMID: 23455963 PMCID: PMC4023649 DOI: 10.1117/1.jbo.18.3.037001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The dual-wavelength diffuse correlation spectroscopy (DCS) flow-oximeter is an emerging technique enabling simultaneous measurements of blood flow and blood oxygenation changes in deep tissues. High signal-to-noise ratio (SNR) is crucial when applying DCS technologies in the study of human tissues where the detected signals are usually very weak. In this study, single-mode, few-mode, and multimode fibers are compared to explore the possibility of improving the SNR of DCS flow-oximeter measurements. Experiments on liquid phantom solutions and in vivo muscle tissues show only slight improvements in flow measurements when using the few-mode fiber compared with using the single-mode fiber. However, light intensities detected by the few-mode and multimode fibers are increased, leading to significant SNR improvements in detections of phantom optical property and tissue blood oxygenation. The outcomes from this study provide useful guidance for the selection of optical fibers to improve DCS flow-oximeter measurements.
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Affiliation(s)
- Lian He
- University of Kentucky, Center for Biomedical Engineering, Lexington, Kentucky 40506
| | - Yu Lin
- University of Kentucky, Center for Biomedical Engineering, Lexington, Kentucky 40506
| | - Yu Shang
- University of Kentucky, Center for Biomedical Engineering, Lexington, Kentucky 40506
| | - Brent J. Shelton
- University of Kentucky, Markey Cancer Center, Lexington, Kentucky 40536
| | - Guoqiang Yu
- University of Kentucky, Center for Biomedical Engineering, Lexington, Kentucky 40506
- Address all correspondence to: Guoqiang Yu, University of Kentucky, Center for Biomedical Engineering, Lexington, Kentucky 40506. Tel: 859-257-9110; Fax: 859-257-1856; E-mail:
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Shang Y, Gurley K, Yu G. Diffuse Correlation Spectroscopy (DCS) for Assessment of Tissue Blood Flow in Skeletal Muscle: Recent Progress. ACTA ACUST UNITED AC 2013; 3:128. [PMID: 24724043 PMCID: PMC3979478 DOI: 10.4172/2161-0940.1000128] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Near-infrared diffuse correlation spectroscopy (DCS) is an emerging technology for monitoring blood flow in various tissues. This article reviews the recent progress of DCS for the assessment of skeletal muscle blood flow, including the developments in technology allowing use during dynamic exercise and muscular electrical stimulation, the utilization for diagnosis of muscle vascular diseases, and the applications for evaluating treatment effects. The limitations of current DCS studies and future perspective are finally discussed.
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Affiliation(s)
- Yu Shang
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY 40506, USA
| | - Katelyn Gurley
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY 40506, USA ; Department of Neurological Surgery, University of Louisville, Louisville, KY 40202, USA
| | - Guoqiang Yu
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY 40506, USA
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Dong L, He L, Lin Y, Shang Y, Yu G. Simultaneously extracting multiple parameters via fitting one single autocorrelation function curve in diffuse correlation spectroscopy. IEEE Trans Biomed Eng 2012. [PMID: 23193446 DOI: 10.1109/tbme.2012.2226885] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Near-infrared diffuse correlation spectroscopy (DCS) has recently been employed for noninvasive acquisition of blood flow information in deep tissues. Based on the established correlation diffusion equation, the light intensity autocorrelation function detected by DCS is determined by a blood flow index αD(B), tissue absorption coefficient μ(a), reduced scattering coefficient μ'(s), and a coherence factor β. This study is designed to investigate the possibility of extracting multiple parameters such as μ(a), μ'(s), β, and αD(B) through fitting one single autocorrelation function curve and evaluate the performance of different fitting methods. For this purpose, computer simulations, tissue-like phantom experiments, and in vivo tissue measurements were utilized. The results suggest that it is impractical to simultaneously fit αD(B) and μ(a) or αD(B) and μ'(s) from one single autocorrelation function curve due to the large crosstalk between these paired parameters. However, simultaneously fitting β and αD(B) is feasible and generates more accurate estimation with smaller standard deviation compared to the conventional two-step fitting method (i.e., first calculating β and then fitting αD(B)). The outcomes from this study provide a crucial guidance for DCS data analysis.
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Affiliation(s)
- Lixin Dong
- Center for Biomedical Engineering, University of Kentucky College of Engineering, Lexington, KY 40506, USA.
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Shang Y, Gurley K, Symons B, Long D, Srikuea R, Crofford LJ, Peterson CA, Yu G. Noninvasive optical characterization of muscle blood flow, oxygenation, and metabolism in women with fibromyalgia. Arthritis Res Ther 2012; 14:R236. [PMID: 23116302 PMCID: PMC3674608 DOI: 10.1186/ar4079] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 10/25/2012] [Indexed: 12/11/2022] Open
Abstract
Introduction Women with fibromyalgia (FM) have symptoms of increased muscular fatigue and reduced exercise tolerance, which may be associated with alterations in muscle microcirculation and oxygen metabolism. This study used near-infrared diffuse optical spectroscopies to noninvasively evaluate muscle blood flow, blood oxygenation and oxygen metabolism during leg fatiguing exercise and during arm arterial cuff occlusion in post-menopausal women with and without FM. Methods Fourteen women with FM and twenty-three well-matched healthy controls participated in this study. For the fatiguing exercise protocol, the subject was instructed to perform 6 sets of 12 isometric contractions of knee extensor muscles with intensity steadily increasing from 20 to 70% maximal voluntary isometric contraction (MVIC). For the cuff occlusion protocol, forearm arterial blood flow was occluded via a tourniquet on the upper arm for 3 minutes. Leg or arm muscle hemodynamics, including relative blood flow (rBF), oxy- and deoxy-hemoglobin concentration ([HbO2] and [Hb]), total hemoglobin concentration (THC) and blood oxygen saturation (StO2), were continuously monitored throughout protocols using a custom-built hybrid diffuse optical instrument that combined a commercial near-infrared oximeter for tissue oxygenation measurements and a custom-designed diffuse correlation spectroscopy (DCS) flowmeter for tissue blood flow measurements. Relative oxygen extraction fraction (rOEF) and oxygen consumption rate (rVO2) were calculated from the measured blood flow and oxygenation data. Post-manipulation (fatiguing exercise or cuff occlusion) recovery in muscle hemodynamics was characterized by the recovery half-time, a time interval from the end of manipulation to the time that tissue hemodynamics reached a half-maximal value. Results Subjects with FM had similar hemodynamic and metabolic response/recovery patterns as healthy controls during exercise and during arterial occlusion. However, tissue rOEF during exercise in subjects with FM was significantly lower than in healthy controls, and the half-times of oxygenation recovery (Δ[HbO2] and Δ[Hb]) were significantly longer following fatiguing exercise and cuff occlusion. Conclusions Our results suggest an alteration of muscle oxygen utilization in the FM population. This study demonstrates the potential of using combined diffuse optical spectroscopies (i.e., NIRS/DCS) to comprehensively evaluate tissue oxygen and flow kinetics in skeletal muscle.
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Cheng R, Shang Y, Hayes D, Saha SP, Yu G. Noninvasive optical evaluation of spontaneous low frequency oscillations in cerebral hemodynamics. Neuroimage 2012; 62:1445-54. [DOI: 10.1016/j.neuroimage.2012.05.069] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 05/11/2012] [Accepted: 05/24/2012] [Indexed: 01/15/2023] Open
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Mesquita RC, Han SW, Miller J, Schenkel SS, Pole A, Esipova TV, Vinogradov SA, Putt ME, Yodh AG, Busch TM. Tumor blood flow differs between mouse strains: consequences for vasoresponse to photodynamic therapy. PLoS One 2012; 7:e37322. [PMID: 22624014 PMCID: PMC3356280 DOI: 10.1371/journal.pone.0037322] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 04/18/2012] [Indexed: 12/25/2022] Open
Abstract
Fluctuations in tumor blood flow are common and attributed to factors such as vasomotion or local vascular structure, yet, because vessel structure and physiology are host-derived, animal strain of tumor propagation may further determine blood flow characteristics. In the present report, baseline and stress-altered tumor hemodynamics as a function of murine strain were studied using radiation-induced fibrosacomas (RIF) grown in C3H or nude mice. Fluctuations in tumor blood flow during one hour of baseline monitoring or during vascular stress induced by photodynamic therapy (PDT) were measured by diffuse correlation spectroscopy. Baseline monitoring revealed fluctuating tumor blood flow highly correlated with heart rate and with similar median periods (i.e., ∼9 and 14 min in C3H and nudes, respectively). However, tumor blood flow in C3H animals was more sensitive to physiologic or stress-induced perturbations. Specifically, PDT-induced vascular insults produced greater decreases in blood flow in the tumors of C3H versus nude mice; similarly, during baseline monitoring, fluctuations in blood flow were more regular and more prevalent within the tumors of C3H mice versus nude mice; finally, the vasoconstrictor L-NNA reduced tumor blood flow in C3H mice but did not affect tumor blood flow in nudes. Underlying differences in vascular structure, such as smaller tumor blood vessels in C3H versus nude animals, may contribute to strain-dependent variation in vascular function. These data thus identify clear effects of mouse strain on tumor hemodynamics with consequences to PDT and potentially other vascular-mediated therapies.
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Affiliation(s)
- Rickson C Mesquita
- Department of Physics & Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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Dong L, Kudrimoti M, Cheng R, Shang Y, Johnson EL, Stevens SD, Shelton BJ, Yu G. Noninvasive diffuse optical monitoring of head and neck tumor blood flow and oxygenation during radiation delivery. BIOMEDICAL OPTICS EXPRESS 2012; 3:259-72. [PMID: 22312579 PMCID: PMC3269843 DOI: 10.1364/boe.3.000259] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Revised: 12/15/2011] [Accepted: 01/01/2012] [Indexed: 05/19/2023]
Abstract
This study explored using a novel diffuse correlation spectroscopy (DCS) flow-oximeter to noninvasively monitor blood flow and oxygenation changes in head and neck tumors during radiation delivery. A fiber-optic probe connected to the DCS flow-oximeter was placed on the surface of the radiologically/clinically involved cervical lymph node. The DCS flow-oximeter in the treatment room was remotely operated by a computer in the control room. From the early measurements, abnormal signals were observed when the optical device was placed in close proximity to the radiation beams. Through phantom tests, the artifacts were shown to be caused by scattered x rays and consequentially avoided by moving the optical device away from the x-ray beams. Eleven patients with head and neck tumors were continually measured once a week over a treatment period of seven weeks, although there were some missing data due to the patient related events. Large inter-patient variations in tumor hemodynamic responses were observed during radiation delivery. A significant increase in tumor blood flow was observed at the first week of treatment, which may be a physiologic response to hypoxia created by radiation oxygen consumption. Only small and insignificant changes were found in tumor blood oxygenation, suggesting that oxygen utilizations in tumors during the short period of fractional radiation deliveries were either minimal or balanced by other effects such as blood flow regulation. Further investigations in a large patient population are needed to correlate the individual hemodynamic responses with the clinical outcomes for determining the prognostic value of optical measurements.
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Affiliation(s)
- Lixin Dong
- Center for Biomedical Engineering, University of Kentucky College of Engineering, Lexington, KY 40506, USA
| | - Mahesh Kudrimoti
- Department of Radiation Medicine, University of Kentucky Chandler Hospital, Lexington, KY 40536, USA
| | - Ran Cheng
- Center for Biomedical Engineering, University of Kentucky College of Engineering, Lexington, KY 40506, USA
| | - Yu Shang
- Center for Biomedical Engineering, University of Kentucky College of Engineering, Lexington, KY 40506, USA
| | - Ellis L. Johnson
- Department of Radiation Medicine, University of Kentucky Chandler Hospital, Lexington, KY 40536, USA
| | - Scott D. Stevens
- Department of Radiology, University of Kentucky Chandler Hospital, Lexington, KY 40536, USA
| | - Brent J. Shelton
- Markey Cancer Center, University of Kentucky College of Medicine, and Department of Biostatistics, University of Kentucky College of Public Health, Lexington, KY 40536, USA
| | - Guoqiang Yu
- Center for Biomedical Engineering, University of Kentucky College of Engineering, Lexington, KY 40506, USA
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