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Mazumder D, Kholiqov O, Srinivasan VJ. Interferometric near-infrared spectroscopy (iNIRS) reveals that blood flow index depends on wavelength. BIOMEDICAL OPTICS EXPRESS 2024; 15:2152-2174. [PMID: 38633063 PMCID: PMC11019706 DOI: 10.1364/boe.507373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 01/16/2024] [Accepted: 01/17/2024] [Indexed: 04/19/2024]
Abstract
Blood flow index (BFI) is an optically accessible parameter, with unit distance-squared-over-time, that is widely used as a proxy for tissue perfusion. BFI is defined as the dynamic scattering probability (i.e. the ratio of dynamic to overall reduced scattering coefficients) times an effective Brownian diffusion coefficient that describes red blood cell (RBC) motion. Here, using a wavelength division multiplexed, time-of-flight- (TOF) - resolved iNIRS system, we obtain TOF-resolved field autocorrelations at 773 nm and 855 nm via the same source and collector. We measure the human forearm, comprising biological tissues with mixed static and dynamic scattering, as well as a purely dynamic scattering phantom. Our primary finding is that forearm BFI increases from 773 nm to 855 nm, though the magnitude of this increase varies across subjects (23% ± 19% for N = 3). However, BFI is wavelength-independent in the purely dynamic scattering phantom. From these data, we infer that the wavelength-dependence of BFI arises from the wavelength-dependence of the dynamic scattering probability. This inference is further supported by RBC scattering literature. Our secondary finding is that the higher-order cumulant terms of the mean squared displacement (MSD) of RBCs are significant, but decrease with wavelength. Thus, laser speckle and related modalities should exercise caution when interpreting field autocorrelations.
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Affiliation(s)
- Dibbyan Mazumder
- Department of Radiology, New York University Langone Health, New York, NY 10016, USA
- Department of Ophthalmology, New York University Langone Health, New York, NY 10016, USA
| | - Oybek Kholiqov
- Department of Biomedical Engineering, University of California Davis, Davis, CA 95616, USA
| | - Vivek J. Srinivasan
- Department of Radiology, New York University Langone Health, New York, NY 10016, USA
- Department of Ophthalmology, New York University Langone Health, New York, NY 10016, USA
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2
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Biswas A, Mohammad PPS, Moka S, Takshi A, Parthasarathy AB. Non-invasive low-cost deep tissue blood flow measurement with integrated Diffuse Speckle Contrast Spectroscopy. FRONTIERS IN NEUROERGONOMICS 2024; 4:1288922. [PMID: 38234484 PMCID: PMC10790947 DOI: 10.3389/fnrgo.2023.1288922] [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: 09/05/2023] [Accepted: 12/19/2023] [Indexed: 01/19/2024]
Abstract
Diffuse Correlation Spectroscopy (DCS) is a widely used non-invasive measurement technique to quantitatively measure deep tissue blood flow. Conventional implementations of DCS use expensive single photon counters as detecting elements and optical probes with bulky fiber optic cables. In recent years, newer approaches to blood flow measurement such as Diffuse Speckle Contrast Analysis (DSCA) and Speckle Contrast Optical Spectroscopy (SCOS), have adapted speckle contrast analysis methods to simplify deep tissue blood flow measurements using cameras and single photon counting avalanche detector arrays as detectors. Here, we introduce and demonstrate integrated Diffuse Speckle Contrast Spectroscopy (iDSCS), a novel optical sensor setup which leverages diffuse speckle contrast analysis for probe-level quantitative measurement of tissue blood flow. iDSCS uses a standard photodiode configured in photovoltaic mode to integrate photon intensity fluctuations over multiple integration durations using a custom electronic circuit, as opposed to the high frequency sampling of photon counts with DCS. We show that the iDSCS device is sensitive to deep-tissue blood flow measurements with experiments on a human forearm and compare the sensitivity and dynamic range of the device to a conventional DCS instrument. The iDSCS device features a low-cost, low-power, small form factor instrument design that will enable wireless probe-level measurements of deep tissue blood flow.
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3
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Zhao H, Sathialingam E, Cowdrick KR, Urner T, Lee SY, Bai S, Akbik F, Samuels OB, Kandiah P, Sadan O, Buckley EM. Comparison of diffuse correlation spectroscopy analytical models for measuring cerebral blood flow in adults. JOURNAL OF BIOMEDICAL OPTICS 2023; 28:126005. [PMID: 38107767 PMCID: PMC10723621 DOI: 10.1117/1.jbo.28.12.126005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 10/30/2023] [Accepted: 11/21/2023] [Indexed: 12/19/2023]
Abstract
Significance Although multilayer analytical models have been proposed to enhance brain sensitivity of diffuse correlation spectroscopy (DCS) measurements of cerebral blood flow, the traditional homogeneous model remains dominant in clinical applications. Rigorous in vivo comparison of these analytical models is lacking. Aim We compare the performance of different analytical models to estimate a cerebral blood flow index (CBFi) with DCS in adults. Approach Resting-state data were obtained on a cohort of 20 adult patients with subarachnoid hemorrhage. Data at 1 and 2.5 cm source-detector separations were analyzed with the homogenous, two-layer, and three-layer models to estimate scalp blood flow index and CBFi. The performance of each model was quantified via fitting convergence, fit stability, brain-to-scalp flow ratio (BSR), and correlation with transcranial Doppler ultrasound (TCD) measurements of cerebral blood flow velocity in the middle cerebral artery (MCA). Results The homogeneous model has the highest pass rate (100%), lowest coefficient of variation (CV) at rest (median [IQR] at 1 Hz of 0.18 [0.13, 0.22]), and most significant correlation with MCA blood flow velocities (R s = 0.59 , p = 0.010 ) compared with both the two- and three-layer models. The multilayer model pass rate was significantly correlated with extracerebral layer thicknesses. Discarding datasets with non-physiological BSRs increased the correlation between DCS measured CBFi and TCD measured MCA velocities for all models. Conclusions We found that the homogeneous model has the highest pass rate, lowest CV at rest, and most significant correlation with MCA blood flow velocities. Results from the multilayer models should be taken with caution because they suffer from lower pass rates and higher coefficients of variation at rest and can converge to non-physiological values for CBFi. Future work is needed to validate these models in vivo, and novel approaches are merited to improve the performance of the multimodel models.
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Affiliation(s)
- Hongting Zhao
- Emory University, Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Eashani Sathialingam
- Emory University, Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Kyle R. Cowdrick
- Emory University, Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Tara Urner
- Emory University, Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Seung Yup Lee
- Emory University, Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
- Kennesaw State University, Department of Electrical and Computer Engineering, Marietta, Georgia, United States
| | - Shasha Bai
- Emory University, School of Medicine, Department of Pediatrics, Atlanta, Georgia, United States
| | - Feras Akbik
- Emory University, School of Medicine, Department of Neurology and Neurosurgery, Division of Neurocritical Care, Atlanta, Georgia, United States
| | - Owen B. Samuels
- Emory University, School of Medicine, Department of Neurology and Neurosurgery, Division of Neurocritical Care, Atlanta, Georgia, United States
| | - Prem Kandiah
- Emory University, School of Medicine, Department of Neurology and Neurosurgery, Division of Neurocritical Care, Atlanta, Georgia, United States
| | - Ofer Sadan
- Emory University, School of Medicine, Department of Neurology and Neurosurgery, Division of Neurocritical Care, Atlanta, Georgia, United States
| | - Erin M. Buckley
- Emory University, Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
- Emory University, School of Medicine, Department of Pediatrics, Atlanta, Georgia, United States
- Children’s Healthcare of Atlanta, Children’s Research Scholar, Atlanta, Georgia, United States
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4
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Favilla CG, Forti RM, Carter S, Kofke WA, Kasner SE, Baker WB, Yodh AG, Messé SR, Cummings S, Kung DK, Burkhardt JK, Choudhri OA, Pukenas B, Srinivasan VM, Hurst RW, Detre JA. Microvascular reperfusion during endovascular therapy: the balance of supply and demand. J Neurointerv Surg 2023:jnis-2023-020834. [PMID: 37898551 PMCID: PMC11055937 DOI: 10.1136/jnis-2023-020834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 10/03/2023] [Indexed: 10/30/2023]
Abstract
BACKGROUND Endovascular therapy (EVT) has revolutionized the treatment of acute stroke, but large vessel recanalization does not always result in tissue-level reperfusion. Cerebral blood flow (CBF) is not routinely monitored during EVT. We aimed to leverage diffuse correlation spectroscopy (DCS), a novel transcranial optical imaging technique, to assess the relationship between microvascular CBF and post-EVT outcomes. METHODS Frontal lobe CBF was monitored by DCS in 40 patients undergoing EVT. Baseline CBF deficit was calculated as the percentage of CBF impairment on pre-EVT CT perfusion. Microvascular reperfusion was calculated as the percentage increase in DCS-derived CBF that occurred with recanalization. The adequacy of reperfusion was defined by persistent CBF deficit, calculated as: baseline CBF deficit - microvascular reperfusion. A good functional outcome was defined as 90-day modified Rankin Scale score ≤2. RESULTS Thirty-six of 40 patients achieved successful recanalization, in whom microvascular reperfusion in itself was not associated with infarct volume or functional outcome. However, patients with good functional outcomes had a smaller persistent CBF deficit (median 1% (IQR -11%-16%)) than patients with poor outcomes (median 28% (IQR 2-50%)) (p=0.02). Smaller persistent CBF deficit was also associated with smaller infarct volume (p=0.004). Multivariate models confirmed that persistent CBF deficit was independently associated with infarct volume and functional outcome. CONCLUSIONS CBF augmentation alone does not predict post-EVT outcomes, but when microvascular reperfusion closely matches the baseline CBF deficit, patients experience favorable clinical and radiographic outcomes. By recognizing inadequate reperfusion, bedside CBF monitoring may provide opportunities to personalize post-EVT care aimed at CBF optimization.
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Affiliation(s)
- Christopher G Favilla
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rodrigo M Forti
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Sarah Carter
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - W Andrew Kofke
- Department of Anesthesia & Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Scott E Kasner
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Wesley B Baker
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Arjun G Yodh
- Department of Physics & Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Steven R Messé
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Stephanie Cummings
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - David K Kung
- Department of Neurosurgery, Robert Wood Johnson Health System, Livingston, New Jersey, USA
| | - Jan Karl Burkhardt
- Department of Neurosurgery, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Omar A Choudhri
- Department of Neurosurgery, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Bryan Pukenas
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Visish M Srinivasan
- Department of Neurosurgery, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Robert W Hurst
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - John A Detre
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Ko TS, Catennacio E, Shin SS, Stern J, Massey SL, Kilbaugh TJ, Hwang M. Advanced Neuromonitoring Modalities on the Horizon: Detection and Management of Acute Brain Injury in Children. Neurocrit Care 2023; 38:791-811. [PMID: 36949362 PMCID: PMC10241718 DOI: 10.1007/s12028-023-01690-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 01/31/2023] [Indexed: 03/24/2023]
Abstract
Timely detection and monitoring of acute brain injury in children is essential to mitigate causes of injury and prevent secondary insults. Increasing survival in critically ill children has emphasized the importance of neuroprotective management strategies for long-term quality of life. In emergent and critical care settings, traditional neuroimaging modalities, such as computed tomography and magnetic resonance imaging (MRI), remain frontline diagnostic techniques to detect acute brain injury. Although detection of structural and anatomical abnormalities remains crucial, advanced MRI sequences assessing functional alterations in cerebral physiology provide unique diagnostic utility. Head ultrasound has emerged as a portable neuroimaging modality for point-of-care diagnosis via assessments of anatomical and perfusion abnormalities. Application of electroencephalography and near-infrared spectroscopy provides the opportunity for real-time detection and goal-directed management of neurological abnormalities at the bedside. In this review, we describe recent technological advancements in these neurodiagnostic modalities and elaborate on their current and potential utility in the detection and management of acute brain injury.
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Affiliation(s)
- Tiffany S Ko
- Department of Anesthesiology and Critical Care, Children's Hospital of Philadelphia, Philadelphia, USA.
| | - Eva Catennacio
- Division of Neurology, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, USA
| | - Samuel S Shin
- Department of Neurosurgery, Hospital of the University of Pennsylvania, Philadelphia, USA
| | - Joseph Stern
- Department of Radiology, Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, USA
| | - Shavonne L Massey
- Division of Neurology, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, USA
| | - Todd J Kilbaugh
- Department of Anesthesiology and Critical Care, Children's Hospital of Philadelphia, Philadelphia, USA
| | - Misun Hwang
- Department of Radiology, Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, USA
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6
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Carp SA, Robinson MB, Franceschini MA. Diffuse correlation spectroscopy: current status and future outlook. NEUROPHOTONICS 2023; 10:013509. [PMID: 36704720 PMCID: PMC9871606 DOI: 10.1117/1.nph.10.1.013509] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 12/23/2022] [Indexed: 06/18/2023]
Abstract
Diffuse correlation spectroscopy (DCS) has emerged as a versatile, noninvasive method for deep tissue perfusion assessment using near-infrared light. A broad class of applications is being pursued in neuromonitoring and beyond. However, technical limitations of the technology as originally implemented remain as barriers to wider adoption. A wide variety of approaches to improve measurement performance and reduce cost are being explored; these include interferometric methods, camera-based multispeckle detection, and long path photon selection for improved depth sensitivity. We review here the current status of DCS technology and summarize future development directions and the challenges that remain on the path to widespread adoption.
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Affiliation(s)
- Stefan A. Carp
- Massachusetts General Hospital, Harvard Medical School, Optics at Martinos Research Group, Charlestown, Massachusetts, United States
| | - Mitchell B. Robinson
- Massachusetts General Hospital, Harvard Medical School, Optics at Martinos Research Group, Charlestown, Massachusetts, United States
| | - Maria A. Franceschini
- Massachusetts General Hospital, Harvard Medical School, Optics at Martinos Research Group, Charlestown, Massachusetts, United States
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7
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Côté-Corriveau G, Simard MN, Beaulieu O, Chowdhury RA, Gagnon MM, Gagnon M, Ledjiar O, Bernard C, Nuyt AM, Dehaes M, Luu TM. Associations between neurological examination at term-equivalent age and cerebral hemodynamics and oxygen metabolism in infants born preterm. Front Neurosci 2023; 17:1105638. [PMID: 36937667 PMCID: PMC10017489 DOI: 10.3389/fnins.2023.1105638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 02/17/2023] [Indexed: 03/06/2023] Open
Abstract
Background Infants born at 29-36 weeks gestational age (GA) are at risk of experiencing neurodevelopmental challenges. We hypothesize that cerebral hemodynamics and oxygen metabolism measured by bedside optical brain monitoring are potential biomarkers of brain development and are associated with neurological examination at term-equivalent age (TEA). Methods Preterm infants (N = 133) born 29-36 weeks GA and admitted in the neonatal intensive care unit were enrolled in this prospective cohort study. Combined frequency-domain near infrared spectroscopy (FDNIRS) and diffuse correlation spectroscopy (DCS) were used from birth to TEA to measure cerebral hemoglobin oxygen saturation and an index of microvascular cerebral blood flow (CBF i ) along with peripheral arterial oxygen saturation (SpO2). In combination with hemoglobin concentration in the blood, these parameters were used to derive cerebral oxygen extraction fraction (OEF) and an index of cerebral oxygen metabolism (CMRO2i ). The Amiel-Tison and Gosselin Neurological Assessment was performed at TEA. Linear regression models were used to assess the associations between changes in FDNIRS-DCS parameters from birth to TEA and GA at birth. Logistic regression models were used to assess the associations between changes in FDNIRS-DCS parameters from birth to TEA and neurological examination at TEA. Results Steeper increases in CBF i (p < 0.0001) and CMRO2i (p = 0.0003) were associated with higher GA at birth. Changes in OEF, CBF i , and CMRO2i from birth to TEA were not associated with neurological examination at TEA. Conclusion In this population, cerebral FDNIRS-DCS parameters were not associated with neurological examination at TEA. Larger increases in CBF i and CMRO2i from birth to TEA were associated with higher GA. Non-invasive bedside FDNIRS-DCS monitoring provides cerebral hemodynamic and metabolic parameters that may complement neurological examination to assess brain development in preterm infants.
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Affiliation(s)
- Gabriel Côté-Corriveau
- Research Center, Sainte-Justine University Hospital Center, Montreal, QC, Canada
- Department of Epidemiology, Biostatistics and Occupational Health, Faculty of Medicine, McGill University, Montreal, QC, Canada
- Department of Pediatrics, Sainte-Justine University Hospital Center, University of Montreal, Montreal, QC, Canada
| | - Marie-Noëlle Simard
- Research Center, Sainte-Justine University Hospital Center, Montreal, QC, Canada
- School of Rehabilitation, University of Montreal, Montreal, QC, Canada
| | - Olivia Beaulieu
- Research Center, Sainte-Justine University Hospital Center, Montreal, QC, Canada
| | - Rasheda Arman Chowdhury
- Research Center, Sainte-Justine University Hospital Center, Montreal, QC, Canada
- Institute of Biomedical Engineering, University of Montreal, Montreal, QC, Canada
| | - Marie-Michèle Gagnon
- Research Center, Sainte-Justine University Hospital Center, Montreal, QC, Canada
| | - Mélanie Gagnon
- Research Center, Sainte-Justine University Hospital Center, Montreal, QC, Canada
| | - Omar Ledjiar
- Unité de Recherche Clinique Appliquée, Sainte-Justine University Hospital Center, Montreal, QC, Canada
| | - Catherine Bernard
- Research Center, Sainte-Justine University Hospital Center, Montreal, QC, Canada
| | - Anne Monique Nuyt
- Research Center, Sainte-Justine University Hospital Center, Montreal, QC, Canada
- Department of Pediatrics, Sainte-Justine University Hospital Center, University of Montreal, Montreal, QC, Canada
| | - Mathieu Dehaes
- Research Center, Sainte-Justine University Hospital Center, Montreal, QC, Canada
- Institute of Biomedical Engineering, University of Montreal, Montreal, QC, Canada
- Department of Radiology, Radio-Oncology and Nuclear Medicine, University of Montreal, Montreal, QC, Canada
- *Correspondence: Mathieu Dehaes,
| | - Thuy Mai Luu
- Research Center, Sainte-Justine University Hospital Center, Montreal, QC, Canada
- Department of Pediatrics, Sainte-Justine University Hospital Center, University of Montreal, Montreal, QC, Canada
- Thuy Mai Luu,
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8
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Helton M, Rajasekhar S, Zerafa S, Vishwanath K, Mycek MA. Numerical approach to quantify depth-dependent blood flow changes in real-time using the diffusion equation with continuous-wave and time-domain diffuse correlation spectroscopy. BIOMEDICAL OPTICS EXPRESS 2023; 14:367-384. [PMID: 36698680 PMCID: PMC9841990 DOI: 10.1364/boe.469419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 11/09/2022] [Accepted: 11/10/2022] [Indexed: 05/11/2023]
Abstract
Diffuse correlation spectroscopy (DCS) is a non-invasive optical technique that can measure brain perfusion by quantifying temporal intensity fluctuations of multiply scattered light. A primary limitation for accurate quantitation of cerebral blood flow (CBF) is the fact that experimental measurements contain information about both extracerebral scalp blood flow (SBF) as well as CBF. Separating CBF from SBF is typically achieved using multiple source-detector channels when using continuous-wave (CW) light sources, or more recently with use of time-domain (TD) techniques. Analysis methods that account for these partial volume effects are often employed to increase CBF contrast. However, a robust, real-time analysis procedure that can separate and quantify SBF and CBF with both traditional CW and TD-DCS measurements is still needed. Here, we validate a data analysis procedure based on the diffusion equation in layered media capable of quantifying both extra- and cerebral blood flow in the CW and TD. We find that the model can quantify SBF and CBF coefficients with less than 5% error compared to Monte Carlo simulations using a 3-layered brain model in both the CW and TD. The model can accurately fit data at a rate of <10 ms for CW data and <250 ms for TD data when using a least-squares optimizer.
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Affiliation(s)
- Michael Helton
- Applied Physics Program, University of Michigan, Ann Arbor, USA
| | - Suraj Rajasekhar
- Cell, Molecular and Structural Biology Program, Miami University, Oxford, OH, USA
| | - Samantha Zerafa
- Biomedical Engineering Department, University of Michigan, Ann Arbor, USA
| | - Karthik Vishwanath
- Cell, Molecular and Structural Biology Program, Miami University, Oxford, OH, USA
- Department of Physics, Miami University, Oxford, OH, USA
| | - Mary-Ann Mycek
- Applied Physics Program, University of Michigan, Ann Arbor, USA
- Biomedical Engineering Department, University of Michigan, Ann Arbor, USA
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9
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Maruccia F, Tagliabue S, Fischer JB, Kacprzak M, Pérez-Hoyos S, Rosas K, Álvarez ID, Sahuquillo J, Durduran T, Poca MA. Transcranial optical monitoring for detecting intracranial pressure alterations in children with benign external hydrocephalus: a proof-of-concept study. NEUROPHOTONICS 2022; 9:045005. [PMID: 36405998 PMCID: PMC9670160 DOI: 10.1117/1.nph.9.4.045005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 10/27/2022] [Indexed: 06/16/2023]
Abstract
SIGNIFICANCE Benign external hydrocephalus (BEH) is considered a self-limiting pathology with a good prognosis. However, some children present a pathological intracranial pressure (ICP) characterized by quantitative and qualitative alterations (the so-called B-waves) that can lead to neurological sequelae. AIM Our purpose was to evaluate whether there were cerebral hemodynamic changes associated with ICP B-waves that could be evaluated with noninvasive neuromonitoring. APPROACH We recruited eleven patients (median age 16 months, range 7 to 55 months) with BEH and an unfavorable evolution requiring ICP monitoring. Bedside, nocturnal monitoring using near-infrared time-resolved and diffuse correlation spectroscopies synchronized to the clinical monitoring was performed. RESULTS By focusing on the timing of different ICP patterns that were identified manually by clinicians, we detected significant tissue oxygen saturation ( StO 2 ) changes ( p = 0.002 ) and blood flow index (BFI) variability ( p = 0.005 ) between regular and high-amplitude B-wave patterns. A blinded analysis looking for analogs of ICP patterns in BFI time traces achieved 90% sensitivity in identifying B-waves and 76% specificity in detecting the regular patterns. CONCLUSIONS We revealed the presence of StO 2 and BFI variations-detectable with optical techniques-during ICP B-waves in BEH children. Finally, the feasibility of detecting ICP B-waves in hemodynamic time traces obtained noninvasively was shown.
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Affiliation(s)
- Federica Maruccia
- Vall d’Hebron Barcelona Hospital Campus, Vall d’Hebron Research Institute, Neurotraumatology and Neurosurgery Research Unit, Barcelona, Spain
- ICFO-Insitut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Susanna Tagliabue
- ICFO-Insitut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Jonas B. Fischer
- ICFO-Insitut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
- HemoPhotonics S.L., Barcelona, Spain
| | - Michał Kacprzak
- ICFO-Insitut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
- Nalecz Institute of Biocybernetics and Biomedical Engineering, Warsaw, Poland
| | - Santi Pérez-Hoyos
- Vall d’Hebron Research Institute, Statistics and Bioinformatics Unit, Barcelona, Spain
| | - Katiuska Rosas
- Vall d’Hebron Barcelona Hospital Campus, Vall d’Hebron Research Institute, Neurotraumatology and Neurosurgery Research Unit, Barcelona, Spain
- Vall d’Hebron Hospital Universitari, Vall d’Hebron Barcelona Hospital Campus, Department of Neurosurgery and Pediatric Neurosurgery Unit, Barcelona, Spain
| | - Ignacio Delgado Álvarez
- Vall d’Hebron Hospital Universitari, Vall d’Hebron Barcelona Hospital Campus, Department of Pediatric Neuroradiology, Barcelona, Spain
| | - Juan Sahuquillo
- Vall d’Hebron Barcelona Hospital Campus, Vall d’Hebron Research Institute, Neurotraumatology and Neurosurgery Research Unit, Barcelona, Spain
- Vall d’Hebron Hospital Universitari, Vall d’Hebron Barcelona Hospital Campus, Department of Neurosurgery and Pediatric Neurosurgery Unit, Barcelona, Spain
- Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Turgut Durduran
- ICFO-Insitut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
| | - Maria A. Poca
- Vall d’Hebron Barcelona Hospital Campus, Vall d’Hebron Research Institute, Neurotraumatology and Neurosurgery Research Unit, Barcelona, Spain
- Vall d’Hebron Hospital Universitari, Vall d’Hebron Barcelona Hospital Campus, Department of Neurosurgery and Pediatric Neurosurgery Unit, Barcelona, Spain
- Universitat Autònoma de Barcelona, Barcelona, Spain
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10
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Wang Y, Tsai CH, Chu TS, Hung YT, Lee MY, Chen HH, Chen LT, Ger TR, Wang YH, Chiang NJ, Liao LD. Revisiting the cerebral hemodynamics of awake, freely moving rats with repeated ketamine self-administration using a miniature photoacoustic imaging system. NEUROPHOTONICS 2022; 9:045003. [PMID: 36338453 PMCID: PMC9623815 DOI: 10.1117/1.nph.9.4.045003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
SIGNIFICANCE Revealing the dynamic associations between brain functions and behaviors is a significant challenge in neurotechnology, especially for awake subjects. Imaging cerebral hemodynamics in awake animal models is important because the collected data more realistically reflect human disease states. AIM We previously reported a miniature head-mounted scanning photoacoustic imaging (hmPAI) system. In the present study, we utilized this system to investigate the effects of ketamine on the cerebral hemodynamics of normal rats and rats subjected to prolonged ketamine self-administration. APPROACH The cortical superior sagittal sinus (SSS) was continuously monitored. The full-width at half-maximum (FWHM) of the photoacoustic (PA) A-line signal was used as an indicator of the SSS diameter, and the number of pixels in PA B-scan images was used to investigate changes in the cerebral blood volume (CBV). RESULTS We observed a significantly higher FWHM (blood vessel diameter) and CBV in normal rats injected with ketamine than in normal rats injected with saline. For rats subjected to prolonged ketamine self-administration, no significant changes in either the blood vessel diameter or CBV were observed. CONCLUSIONS The lack of significant change in prolonged ketamine-exposed rats was potentially due to an increased ketamine tolerance. Our device can reliably detect changes in the dilation of cortical blood vessels and the CBV. This study validates the utility of the developed hmPAI system in an awake, freely moving rat model for behavioral, cognitive, and preclinical cerebral disease studies.
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Affiliation(s)
- Yuhling Wang
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
| | - Chia-Hua Tsai
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
| | - Tsung-Sheng Chu
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
- Chung Yuan Christian University, Department of Biomedical Engineering, Taoyuan City, Taiwan
| | - Yun-Ting Hung
- National Health Research Institutes, Center for Neuropsychiatric Research, Zhunan Town, Miaoli County, Taiwan
| | - Mei-Yi Lee
- National Health Research Institutes, Center for Neuropsychiatric Research, Zhunan Town, Miaoli County, Taiwan
| | - Hwei-Hsien Chen
- National Health Research Institutes, Center for Neuropsychiatric Research, Zhunan Town, Miaoli County, Taiwan
| | - Li-Tzong Chen
- Kaohsiung Medical University, Kaohsiung Medical University Hospital, Kaohsiung City, Taiwan
- National Health Research Institutes, National Institute of Cancer Research, Zhunan Town, Miaoli County, Taiwan
| | - Tzong-Rong Ger
- Chung Yuan Christian University, Department of Biomedical Engineering, Taoyuan City, Taiwan
| | - Yung-Hsuan Wang
- National Health Research Institutes, National Institute of Cancer Research, Zhunan Town, Miaoli County, Taiwan
| | - Nai-Jung Chiang
- National Health Research Institutes, National Institute of Cancer Research, Zhunan Town, Miaoli County, Taiwan
- Taipei Veterans General Hospital, Department of Oncology, Taipei City, Taiwan
| | - Lun-De Liao
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
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11
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Sunwoo J, Zavriyev AI, Kaya K, Martin A, Munster C, Steele T, Cuddyer D, Sheldon Y, Orihuela-Espina F, Herzberg EM, Inder T, Franceschini MA, El-Dib M. Diffuse correlation spectroscopy blood flow monitoring for intraventricular hemorrhage vulnerability in extremely low gestational age newborns. Sci Rep 2022; 12:12798. [PMID: 35896691 PMCID: PMC9329437 DOI: 10.1038/s41598-022-16499-3] [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: 03/22/2022] [Accepted: 07/11/2022] [Indexed: 11/17/2022] Open
Abstract
In premature infants with an extremely low gestational age (ELGA, < 29 weeks GA), dysregulated changes in cerebral blood flow (CBF) are among the major pathogenic factors leading to germinal matrix/intraventricular hemorrhage (GM/IVH). Continuous monitoring of CBF can guide interventions to minimize the risk of brain injury, but there are no clinically standard techniques or tools for its measurement. We report the feasibility of the continuous monitoring of CBF, including measures of autoregulation, via diffuse correlation spectroscopy (DCS) in ELGA infants using CBF variability and correlation with scalp blood flow (SBF, served as a surrogate measure of systemic perturbations). In nineteen ELGA infants (with 9 cases of GM/IVH) monitored for 6–24 h between days 2–5 of life, we found a strong correlation between CBF and SBF in severe IVH (Grade III or IV) and IVH diagnosed within 72 h of life, while CBF variability alone was not associated with IVH. The proposed method is potentially useful at the bedside for the prompt assessment of cerebral autoregulation and early identification of infants vulnerable to GM/IVH.
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Affiliation(s)
- John Sunwoo
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
| | - Alexander I Zavriyev
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Kutlu Kaya
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Alyssa Martin
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Chelsea Munster
- Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Tina Steele
- Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Deborah Cuddyer
- Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Yvonne Sheldon
- Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Emily M Herzberg
- Division of Neonatology and Newborn Medicine, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Terrie Inder
- Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Maria Angela Franceschini
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Mohamed El-Dib
- Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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12
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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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13
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Johnson TW, Dar IA, Donohue KL, Xu YY, Santiago E, Selioutski O, Marinescu MA, Maddox RK, Wu TT, Schifitto G, Gosev I, Choe R, Khan IR. Cerebral Blood Flow Hemispheric Asymmetry in Comatose Adults Receiving Extracorporeal Membrane Oxygenation. Front Neurosci 2022; 16:858404. [PMID: 35478849 PMCID: PMC9036108 DOI: 10.3389/fnins.2022.858404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 03/09/2022] [Indexed: 12/03/2022] Open
Abstract
Peripheral veno-arterial extracorporeal membrane oxygenation (ECMO) artificially oxygenates and circulates blood retrograde from the femoral artery, potentially exposing the brain to asymmetric perfusion. Though ECMO patients frequently experience brain injury, neurologic exams and imaging are difficult to obtain. Diffuse correlation spectroscopy (DCS) non-invasively measures relative cerebral blood flow (rBF) at the bedside using an optical probe on each side of the forehead. In this study we observed interhemispheric rBF differences in response to mean arterial pressure (MAP) changes in adult ECMO recipients. We recruited 13 subjects aged 21–78 years (7 with cardiac arrest, 4 with acute heart failure, and 2 with acute respiratory distress syndrome). They were dichotomized via Glasgow Coma Scale Motor score (GCS-M) into comatose (GCS-M ≤ 4; n = 4) and non-comatose (GCS-M > 4; n = 9) groups. Comatose patients had greater interhemispheric rBF asymmetry (ASYMrBF) vs. non-comatose patients over a range of MAP values (29 vs. 11%, p = 0.009). ASYMrBF in comatose patients resolved near a MAP range of 70–80 mmHg, while rBF remained symmetric through a wider MAP range in non-comatose patients. Correlations between post-oxygenator pCO2 or pH vs. ASYMrBF were significantly different between comatose and non-comatose groups. Our findings indicate that comatose patients are more likely to have asymmetric cerebral perfusion.
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Affiliation(s)
- Thomas W. Johnson
- Department of Neurology, University of Rochester Medical Center, Rochester, NY, United States
| | - Irfaan A. Dar
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, United States
| | - Kelly L. Donohue
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Yama Y. Xu
- School of Arts and Sciences, University of Rochester, Rochester, NY, United States
| | - Esmeralda Santiago
- School of Arts and Sciences, University of Rochester, Rochester, NY, United States
| | - Olga Selioutski
- Department of Neurology, University of Rochester Medical Center, Rochester, NY, United States
| | - Mark A. Marinescu
- Department of Medicine, University of Rochester Medical Center, Rochester, NY, United States
| | - Ross K. Maddox
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, United States
- Department of Neuroscience, University of Rochester Medical Center, Rochester, NY, United States
| | - Tong Tong Wu
- Department of Biostatistics and Computational Biology, University of Rochester, Rochester, NY, United States
| | - Giovanni Schifitto
- Department of Neurology, University of Rochester Medical Center, Rochester, NY, United States
| | - Igor Gosev
- Division of Cardiac Surgery, Department of Surgery, University of Rochester Medical Center, Rochester, NY, United States
| | - Regine Choe
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, United States
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, NY, United States
| | - Imad R. Khan
- Department of Neurology, University of Rochester Medical Center, Rochester, NY, United States
- *Correspondence: Imad R. Khan,
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14
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Matsuda Y, Nakabayashi M, Suzuki T, Zhang S, Ichinose M, Ono Y. Evaluation of Local Skeletal Muscle Blood Flow in Manipulative Therapy by Diffuse Correlation Spectroscopy. Front Bioeng Biotechnol 2022; 9:800051. [PMID: 35087803 PMCID: PMC8786806 DOI: 10.3389/fbioe.2021.800051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 12/17/2021] [Indexed: 11/13/2022] Open
Abstract
Manipulative therapy (MT) is applied to motor organs through a therapist’s hands. Although MT has been utilized in various medical treatments based on its potential role for increasing the blood flow to the local muscle, a quantitative validation of local muscle blood flow in MT remains challenging due to the lack of appropriate bedside evaluation techniques. Therefore, we investigated changes in the local blood flow to the muscle undergoing MT by employing diffuse correlation spectroscopy, a portable and emerging optical measurement technology that non-invasively measures blood flow in deep tissues. This study investigated the changes in blood flow, heart rate, blood pressure, and autonomic nervous activity in the trapezius muscle through MT application in 30 volunteers without neck and shoulder injury. Five minutes of MT significantly increased the median local blood flow relative to that of the pre-MT period (p < 0.05). The post-MT local blood flow increase was significantly higher in the MT condition than in the control condition, where participants remained still without receiving MT for the same time (p < 0.05). However, MT did not affect the heart rate, blood pressure, or cardiac autonomic nervous activity. The post-MT increase in muscle blood flow was significantly higher in the participants with muscle stiffness in the neck and shoulder regions than in those without (p < 0.05). These results suggest that MT could increase the local blood flow to the target skeletal muscle, with minimal effects on systemic circulatory function.
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Affiliation(s)
- Yasuhiro Matsuda
- Electrical Engineering Program, Graduate School of Science and Technology, Meiji University, Kawasaki, Japan
- Faculty of Medical Science, Nippon Sport Science University, Yokohama, Japan
| | - Mikie Nakabayashi
- Electrical Engineering Program, Graduate School of Science and Technology, Meiji University, Kawasaki, Japan
- Japan Society for the Promotion of Science (JSPS), Tokyo, Japan
| | - Tatsuya Suzuki
- Electrical Engineering Program, Graduate School of Science and Technology, Meiji University, Kawasaki, Japan
| | - Sinan Zhang
- Electrical Engineering Program, Graduate School of Science and Technology, Meiji University, Kawasaki, Japan
- Department of Electronics and Bioinformatics, School of Science and Technology, Meiji University, Kawasaki, Japan
| | - Masashi Ichinose
- Human Integrative Physiology Laboratory, School of Business Administration, Meiji University, Tokyo, Japan
| | - Yumie Ono
- Department of Electronics and Bioinformatics, School of Science and Technology, Meiji University, Kawasaki, Japan
- *Correspondence: Yumie Ono,
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15
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Biswas A, Moka S, Muller A, Parthasarathy AB. Fast diffuse correlation spectroscopy with a low-cost, fiber-less embedded diode laser. BIOMEDICAL OPTICS EXPRESS 2021; 12:6686-6700. [PMID: 34858674 PMCID: PMC8606156 DOI: 10.1364/boe.435136] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 09/20/2021] [Accepted: 09/21/2021] [Indexed: 06/02/2023]
Abstract
Diffuse correlation spectroscopy (DCS), a popular optical technique for fast noninvasive measurement of blood flow, is commonly implemented using expensive fiber-coupled long coherence length laser systems. Here, we report the development of a portable and fiber-less approach that can be used as a low-cost alternative to illuminate tissue in DCS instruments. We validate the accuracy and noise characteristics of the fiber-less DCS laser source, by comparisons against traditional DCS light sources, with experiments on controlled tissue-simulating phantoms and in humans.
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Affiliation(s)
- Arindam Biswas
- Department of Electrical Engineering, University of South Florida, 4202 E. Fowler Avenue, ENG030, Tampa, FL 33620, USA
| | - Sadhu Moka
- Department of Electrical Engineering, University of South Florida, 4202 E. Fowler Avenue, ENG030, Tampa, FL 33620, USA
| | - Andreas Muller
- Department of Physics, University of South Florida, 4202 E. Fowler Avenue, ISA2019, Tampa, FL 33620, USA
| | - Ashwin B. Parthasarathy
- Department of Electrical Engineering, University of South Florida, 4202 E. Fowler Avenue, ENG030, Tampa, FL 33620, USA
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16
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Zhao H, Sathialingam E, Buckley EM. Accuracy of diffuse correlation spectroscopy measurements of cerebral blood flow when using a three-layer analytical model. BIOMEDICAL OPTICS EXPRESS 2021; 12:7149-7161. [PMID: 34858706 PMCID: PMC8606134 DOI: 10.1364/boe.438303] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 10/15/2021] [Accepted: 10/15/2021] [Indexed: 05/06/2023]
Abstract
Diffuse correlation spectroscopy (DCS) is a non-invasive optical technology for the assessment of an index of cerebral blood flow (CBFi). Analytical methods that model the head as a three-layered medium (i.e., scalp, skull, brain) are becoming more commonly used to minimize the contribution of extracerebral layers to the measured DCS signal in adult cerebral blood flow studies. However, these models rely on a priori knowledge of layer optical properties and thicknesses. Errors in these values can lead to errors in the estimation of CBFi, although the magnitude of this influence has not been rigorously characterized. Herein, we investigate the accuracy of measuring cerebral blood flow with a three-layer model when errors in layer optical properties or thicknesses are present. Through a series of in silico experiments, we demonstrate that CBFi is highly sensitive to errors in brain optical properties and skull and scalp thicknesses. Relative changes in CBFi are less sensitive to optical properties but are influenced by errors in layer thickness. Thus, when using the three-layer model, accurate estimation of scalp and skull thickness are required for reliable results.
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Affiliation(s)
- Hongting Zhao
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Dr. NE, Atlanta, GA 30322, USA
| | - Eashani Sathialingam
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Dr. NE, 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, Emory University School of Medicine, 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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17
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Busch DR, Lin W, Goh CC, Gao F, Larson N, Wahl J, Bilfinger TV, Yodh AG, Floyd TF. Towards rapid intraoperative axial localization of spinal cord ischemia with epidural diffuse correlation monitoring. PLoS One 2021; 16:e0251271. [PMID: 33970932 PMCID: PMC8109798 DOI: 10.1371/journal.pone.0251271] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 04/23/2021] [Indexed: 11/19/2022] Open
Abstract
Spinal cord ischemia leads to iatrogenic injury in multiple surgical fields, and the ability to immediately identify onset and anatomic origin of ischemia is critical to its management. Current clinical monitoring, however, does not directly measure spinal cord blood flow, resulting in poor sensitivity/specificity, delayed alerts, and delayed intervention. We have developed an epidural device employing diffuse correlation spectroscopy (DCS) to monitor spinal cord ischemia continuously at multiple positions. We investigate the ability of this device to localize spinal cord ischemia in a porcine model and validate DCS versus Laser Doppler Flowmetry (LDF). Specifically, we demonstrate continuous (>0.1Hz) spatially resolved (3 locations) monitoring of spinal cord blood flow in a purely ischemic model with an epidural DCS probe. Changes in blood flow measured by DCS and LDF were highly correlated (r = 0.83). Spinal cord blood flow measured by DCS caudal to aortic occlusion decreased 62%. This monitor demonstrated a sensitivity of 0.87 and specificity of 0.91 for detection of a 25% decrease in flow. This technology may enable early identification and critically important localization of spinal cord ischemia.
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Affiliation(s)
- David R. Busch
- Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Neurology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Wei Lin
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Chia Chieh Goh
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Feng Gao
- Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Nicholas Larson
- Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Joseph Wahl
- Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Thomas V. Bilfinger
- Department of Surgery, Stony Brook University, Stony Brook, New York, United States of America
| | - Arjun G. Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Thomas F. Floyd
- Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Cardiothoracic Surgery, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- * E-mail:
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18
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Jang JH, Solarana K, Hammer DX, Fisher JAN. Dissecting the microvascular contributions to diffuse correlation spectroscopy measurements of cerebral hemodynamics using optical coherence tomography angiography. NEUROPHOTONICS 2021; 8:025006. [PMID: 33912621 PMCID: PMC8071783 DOI: 10.1117/1.nph.8.2.025006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 03/19/2021] [Indexed: 06/12/2023]
Abstract
Significance: Diffuse correlation spectroscopy (DCS) is an emerging noninvasive, diffuse optical modality that purportedly enables direct measurements of microvasculature blood flow. Functional optical coherence tomography angiography (OCT-A) can resolve blood flow in vessels as fine as capillaries and thus has the capability to validate key attributes of the DCS signal. Aim: To characterize activity in cortical vasculature within the spatial volume that is probed by DCS and to identify populations of blood vessels that are most representative of the DCS signals. Approach: We performed simultaneous measurements of somatosensory-evoked cerebral blood flow in mice in vivo using both DCS and OCT-A. Results: We resolved sensory-evoked blood flow in the somatosensory cortex with both modalities. Vessels with diameters smaller than 10 μ m featured higher peak flow rates during the initial poststimulus positive increase in flow, whereas larger vessels exhibited considerably larger magnitude of the subsequent undershoot. The simultaneously recorded DCS waveforms correlated most highly with flow in the smallest vessels, yet featured a more prominent undershoot. Conclusions: Our direct, multiscale, multimodal cross-validation measurements of functional blood flow support the assertion that the DCS signal preferentially represents flow in microvasculature. The significantly greater undershoot in DCS, however, suggests a more spatially complex relationship to flow in cortical vasculature during functional activation.
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Affiliation(s)
- James H. Jang
- Center for Devices and Radiological Health, U. S. Food and Drug Administration, Silver Spring, Maryland, United States
| | - Krystyna Solarana
- Center for Devices and Radiological Health, U. S. Food and Drug Administration, Silver Spring, Maryland, United States
| | - Daniel X. Hammer
- Center for Devices and Radiological Health, U. S. Food and Drug Administration, Silver Spring, Maryland, United States
| | - Jonathan A. N. Fisher
- New York Medical College, Department of Physiology, Valhalla, New York, United States
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19
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Ruesch A, Acharya D, Schmitt S, Yang J, Smith MA, Kainerstorfer JM. Comparison of static and dynamic cerebral autoregulation under anesthesia influence in a controlled animal model. PLoS One 2021; 16:e0245291. [PMID: 33418561 PMCID: PMC7794034 DOI: 10.1371/journal.pone.0245291] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 12/25/2020] [Indexed: 12/30/2022] Open
Abstract
The brain’s ability to maintain cerebral blood flow approximately constant despite cerebral perfusion pressure changes is known as cerebral autoregulation (CA) and is governed by vasoconstriction and vasodilation. Cerebral perfusion pressure is defined as the pressure gradient between arterial blood pressure and intracranial pressure. Measuring CA is a challenging task and has created a variety of evaluation methods, which are often categorized as static and dynamic CA assessments. Because CA is quantified as the performance of a regulatory system and no physical ground truth can be measured, conflicting results are reported. The conflict further arises from a lack of healthy volunteer data with respect to cerebral perfusion pressure measurements and the variety of diseases in which CA ability is impaired, including stroke, traumatic brain injury and hydrocephalus. To overcome these differences, we present a healthy non-human primate model in which we can control the ability to autoregulate blood flow through the type of anesthesia (isoflurane vs fentanyl). We show how three different assessment methods can be used to measure CA impairment, and how static and dynamic autoregulation compare under challenges in intracranial pressure and blood pressure. We reconstructed Lassen’s curve for two groups of anesthesia, where only the fentanyl anesthetized group yielded the canonical shape. Cerebral perfusion pressure allowed for the best distinction between the fentanyl and isoflurane anesthetized groups. The autoregulatory response time to induced oscillations in intracranial pressure and blood pressure, measured as the phase lag between intracranial pressure and blood pressure, was able to determine autoregulatory impairment in agreement with static autoregulation. Static and dynamic CA both show impairment in high dose isoflurane anesthesia, while low isoflurane in combination with fentanyl anesthesia maintains CA, offering a repeatable animal model for CA studies.
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Affiliation(s)
- Alexander Ruesch
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Deepshikha Acharya
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Samantha Schmitt
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Jason Yang
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Matthew A Smith
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Jana M Kainerstorfer
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
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20
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Brothers RO, Atlas N, Cowdrick KR, Buckley EM. Cerebrovascular reactivity measured in awake mice using diffuse correlation spectroscopy. NEUROPHOTONICS 2021; 8:015007. [PMID: 33665230 PMCID: PMC7920384 DOI: 10.1117/1.nph.8.1.015007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 01/15/2021] [Indexed: 05/31/2023]
Abstract
Significance: Cerebrovascular reactivity (CVR), defined as the ability of the cerebral vasculature to dilate or constrict in response to a vasoactive stimulus, is an important indicator of the brain's vascular health. However, mechanisms of cerebrovascular dysregulation are poorly understood, and no effective treatment strategies for impaired CVR exist. Preclinical murine models provide an excellent platform for interrogating mechanisms underlying CVR dysregulation and determining novel therapeutics that restore impaired CVR. However, quantification of CVR in mice is challenging. Aim: We present means of assessing CVR in awake mice using intraperitoneal injection of acetazolamide (ACZ) combined with continuous monitoring of cerebral blood flow. Approach: Measurements of cerebral blood flow were made with a minimally invasive diffuse correlation spectroscopy sensor that was secured to an optical window glued to the intact skull. Two source-detector separations (3 and 4.5 mm) per hemisphere were used to probe different depths. CVR was quantified as the relative increase in blood flow due to ACZ. CVR was assessed once daily for 5 days in 5 mice. Results: We found that CVR and the response half-time were remarkably similar across hemispheres and across 3- versus 4.5-mm separations, suggesting a homogenous, whole brain response to ACZ. Mean(std) intra- and intermouse coefficients of variations were 15(9)% and 19(10)%, respectively, for global CVR and 24(15)% and 27(11)%, respectively, for global response half-time. Conclusion: In sum, we report a repeatable method of measuring CVR in free-behaving mice which can be used to screen for impairments with disease and to track changes in CVR with therapeutic interventions.
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Affiliation(s)
- Rowan O. Brothers
- Emory University and Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Nir Atlas
- Emory University and Children’s Healthcare of Atlanta, Division of Critical Care Medicine, Department of Pediatrics, Atlanta, Georgia, United States
| | - Kyle R. Cowdrick
- Emory University and Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Erin M. Buckley
- Emory University and Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
- Emory University School of Medicine, Department of Pediatrics, Atlanta, Georgia, United States
- Children’s Healthcare of Atlanta, Children’s Research Scholar, Atlanta, Georgia, United States
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21
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McManus R, Ioussoufovitch S, Froats E, St Lawrence K, Van Uum S, Diop M. Dynamic response of cerebral blood flow to insulin-induced hypoglycemia. Sci Rep 2020; 10:21300. [PMID: 33277531 PMCID: PMC7718270 DOI: 10.1038/s41598-020-77626-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 11/11/2020] [Indexed: 11/25/2022] Open
Abstract
The dynamics of cerebral blood flow (CBF) at the onset of hypoglycemia may play a key role in hypoglycemia unawareness; however, there is currently a paucity of techniques that can monitor adult CBF with high temporal resolution. Herein, we investigated the use of diffuse correlation spectroscopy (DCS) to monitor the dynamics of CBF during insulin-induced hypoglycemia in adults. Plasma glucose concentrations, cortisol levels, and changes in CBF were measured before and during hypoglycemia in 8 healthy subjects. Cerebral blood flow increased by 42% following insulin injection with a delay of 17 ± 10 min, while the onset of hypoglycemia symptoms was delayed by 24 ± 11 min. The findings suggest that the onset of CBF increments precedes the appearance of hypoglycemia symptoms in nondiabetic subjects with normal awareness to hypoglycemia, and DCS could be a valuable tool for investigating the role of CBF in hypoglycemia unawareness.
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Affiliation(s)
- Ruth McManus
- St. Joseph's Health Care, London, ON, N6A 4V2, Canada
| | - Seva Ioussoufovitch
- Department of Biomedical Engineering, Western University, London, ON, N6A 5C1, Canada
| | | | - Keith St Lawrence
- St. Joseph's Health Care, London, ON, N6A 4V2, Canada
- Department of Medical Biophysics, Western University, London, ON, N6A 5C1, Canada
| | - Stan Van Uum
- St. Joseph's Health Care, London, ON, N6A 4V2, Canada
| | - Mamadou Diop
- St. Joseph's Health Care, London, ON, N6A 4V2, Canada.
- Department of Biomedical Engineering, Western University, London, ON, N6A 5C1, Canada.
- Department of Medical Biophysics, Western University, London, ON, N6A 5C1, Canada.
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Fisher JAN, Gumenchuk I, Rogovin OS, Yodh AG, Busch DR. Asymmetric, dynamic adaptation in prefrontal cortex during dichotic listening tasks. NEUROPHOTONICS 2020; 7:045008. [PMID: 33163546 PMCID: PMC7641958 DOI: 10.1117/1.nph.7.4.045008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 10/02/2020] [Indexed: 05/25/2023]
Abstract
Significance: Speech processing tasks can be used to assess the integrity and health of many functional and structural aspects of the brain. Despite the potential merits of such behavioral tests as clinical assessment tools, however, the underlying neural substrates remain relatively unclear. Aim: We aimed to obtain a more in-depth portrait of hemispheric asymmetry during dichotic listening tasks at the level of the prefrontal cortex, where prior studies have reported inconsistent results. Approach: To avoid central confounds that limited previous studies, we used diffuse correlation spectroscopy to optically monitor cerebral blood flow (CBF) in the dorsolateral prefrontal cortex during dichotic listening tasks in human subjects. Results: We found that dichotic listening tasks elicited hemispheric asymmetries in both amplitude as well as kinetics. When listening task blocks were repeated, there was an accommodative reduction in the response amplitude of the left, but not the right hemisphere. Conclusions: These heretofore unobserved trends depict a more nuanced portrait of the functional asymmetry that has been observed previously. To our knowledge, these results additionally represent the first direct measurements of CBF during a speech processing task recommended by the American Speech-Language-Hearing Association for diagnosing auditory processing disorders.
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Affiliation(s)
- Jonathan A. N. Fisher
- New York Medical College, Department of Physiology, Valhalla, New York, United States
| | - Iryna Gumenchuk
- New York Medical College, Department of Physiology, Valhalla, New York, United States
| | - Ora S. Rogovin
- New York Medical College, Department of Physiology, Valhalla, New York, United States
| | - Arjun G. Yodh
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
| | - David R. Busch
- University of Texas Southwestern Medical Center, Department of Anesthesiology and Pain Management, Dallas, Texas, United States
- University of Texas Southwestern Medical Center, Department of Neurology, Dallas, Texas, United States
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23
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Carp SA, Tamborini D, Mazumder D, Wu KC(T, Robinson MR, Stephens KA, Shatrovoy O, Lue N, Ozana N, Blackwell MH, Franceschini MA. Diffuse correlation spectroscopy measurements of blood flow using 1064 nm light. JOURNAL OF BIOMEDICAL OPTICS 2020; 25:JBO-200140RR. [PMID: 32996299 PMCID: PMC7522668 DOI: 10.1117/1.jbo.25.9.097003] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 09/11/2020] [Indexed: 05/18/2023]
Abstract
SIGNIFICANCE Diffuse correlation spectroscopy (DCS) is an established optical modality that enables noninvasive measurements of blood flow in deep tissue by quantifying the temporal light intensity fluctuations generated by dynamic scattering of moving red blood cells. Compared with near-infrared spectroscopy, DCS is hampered by a limited signal-to-noise ratio (SNR) due to the need to use small detection apertures to preserve speckle contrast. However, DCS is a dynamic light scattering technique and does not rely on hemoglobin contrast; thus, there are significant SNR advantages to using longer wavelengths (>1000 nm) for the DCS measurement due to a variety of biophysical and regulatory factors. AIM We offer a quantitative assessment of the benefits and challenges of operating DCS at 1064 nm versus the typical 765 to 850 nm wavelength through simulations and experimental demonstrations. APPROACH We evaluate the photon budget, depth sensitivity, and SNR for detecting blood flow changes using numerical simulations. We discuss continuous wave (CW) and time-domain (TD) DCS hardware considerations for 1064 nm operation. We report proof-of-concept measurements in tissue-like phantoms and healthy adult volunteers. RESULTS DCS at 1064 nm offers higher intrinsic sensitivity to deep tissue compared with DCS measurements at the typically used wavelength range (765 to 850 nm) due to increased photon counts and a slower autocorrelation decay. These advantages are explored using simulations and are demonstrated using phantom and in vivo measurements. We show the first high-speed (cardiac pulsation-resolved), high-SNR measurements at large source-detector separation (3 cm) for CW-DCS and late temporal gates (1 ns) for TD-DCS. CONCLUSIONS DCS at 1064 nm offers a leap forward in the ability to monitor deep tissue blood flow and could be especially useful in increasing the reliability of cerebral blood flow monitoring in adults.
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Affiliation(s)
- Stefan A. Carp
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
- Address all correspondence to Stefan A. Carp, E-mail:
| | - Davide Tamborini
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Dibbyan Mazumder
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Kuan-Cheng (Tony) Wu
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
- Boston University, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Mitchell R. Robinson
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
- MIT, Health Sciences and Technology Program, Cambridge, Massachusetts, United States
| | - Kimberly A. Stephens
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Oleg Shatrovoy
- MIT Lincoln Laboratory, Lexington, Massachusetts, United States
| | - Niyom Lue
- MIT Lincoln Laboratory, Lexington, Massachusetts, United States
| | - Nisan Ozana
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | | | - Maria A. Franceschini
- Massachusetts General Hospital, Harvard Medical School, Optics at Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
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24
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Roberts SB, Franceschini MA, Silver RE, Taylor SF, de Sa AB, Có R, Sonco A, Krauss A, Taetzsch A, Webb P, Das SK, Chen CY, Rogers BL, Saltzman E, Lin PY, Schlossman N, Pruzensky W, Balé C, Chui KKH, Muentener P. Effects of food supplementation on cognitive function, cerebral blood flow, and nutritional status in young children at risk of undernutrition: randomized controlled trial. BMJ 2020; 370:m2397. [PMID: 32699176 PMCID: PMC7374799 DOI: 10.1136/bmj.m2397] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/04/2020] [Indexed: 01/06/2023]
Abstract
OBJECTIVE To assess the effects of food supplementation on improving working memory and additional measures including cerebral blood flow in children at risk of undernutrition. DESIGN Randomized controlled trial. SETTING 10 villages in Guinea-Bissau. PARTICIPANTS 1059 children aged 15 months to 7 years; children younger than 4 were the primary population. INTERVENTIONS Supervised isocaloric servings (≈1300 kJ, five mornings each week, 23 weeks) of a new food supplement (NEWSUP, high in plant polyphenols and omega 3 fatty acids, within a wide variety and high fortification of micronutrients, and a high protein content), or a fortified blended food (FBF) used in nutrition programs, or a control meal (traditional rice breakfast). MAIN OUTCOME MEASUREMENTS The primary outcome was working memory, a core executive function predicting long term academic achievement. Additional outcomes were hemoglobin concentration, growth, body composition, and index of cerebral blood flow (CBFi). In addition to an intention-to-treat analysis, a predefined per protocol analysis was conducted in children who consumed at least 75% of the supplement (820/925, 89%). The primary outcome was assessed by a multivariable Poisson model; other outcomes were assessed by multivariable linear mixed models. RESULTS Among children younger than 4, randomization to NEWSUP increased working memory compared with the control meal (rate ratio 1.20, 95% confidence interval 1.02 to 1.41, P=0.03), with a larger effect in the per protocol population (1.25, 1.06 to 1.47, P=0.009). NEWSUP also increased hemoglobin concentration among children with anemia (adjusted mean difference 0.65 g/dL, 95% confidence interval 0.23 to 1.07, P=0.003) compared with the control meal, decreased body mass index z score gain (-0.23, -0.43 to -0.02, P=0.03), and increased lean tissue accretion (2.98 cm2, 0.04 to 5.92, P=0.046) with less fat (-5.82 cm2, -11.28 to -0.36, P=0.04) compared with FBF. Additionally, NEWSUP increased CBFi compared with the control meal and FBF in both age groups combined (1.14 mm2/s×10-8, 0.10 to 2.23, P=0.04 for both comparisons). Among children aged 4 and older, NEWSUP had no significant effect on working memory or anemia, but increased lean tissue compared with FBF (4.31 cm2, 0.34 to 8.28, P=0.03). CONCLUSIONS Childhood undernutrition is associated with long term impairment in cognition. Contrary to current understanding, supplementary feeding for 23 weeks could improve executive function, brain health, and nutritional status in vulnerable young children living in low income countries. Further research is needed to optimize nutritional prescriptions for regenerative improvements in cognitive function, and to test effectiveness in other vulnerable groups. TRIAL REGISTRATION ClinicalTrials.gov NCT03017209.
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Affiliation(s)
- Susan B Roberts
- Gerald J and Dorothy R Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, USA
| | - Maria A Franceschini
- Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Rachel E Silver
- Gerald J and Dorothy R Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, USA
| | - Salima F Taylor
- Gerald J and Dorothy R Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, USA
| | - Augusto Braima de Sa
- International Partnership for Human Development, Leesburg, VA, USA and Bissau, Guinea Bissau
| | - Raimundo Có
- International Partnership for Human Development, Leesburg, VA, USA and Bissau, Guinea Bissau
| | - Aliu Sonco
- International Partnership for Human Development, Leesburg, VA, USA and Bissau, Guinea Bissau
| | | | - Amy Taetzsch
- Gerald J and Dorothy R Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, USA
| | - Patrick Webb
- Gerald J and Dorothy R Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, USA
| | - Sai Krupa Das
- Gerald J and Dorothy R Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, USA
| | - C-Y Chen
- Biofortis, Mérieux NutriSciences, Addison, IL, USA
| | - Beatrice L Rogers
- Gerald J and Dorothy R Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, USA
| | - Edward Saltzman
- Gerald J and Dorothy R Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, USA
| | - Pei-Yi Lin
- Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Nina Schlossman
- Gerald J and Dorothy R Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, USA
- Global Food and Nutrition, Washington, DC, USA
| | - William Pruzensky
- International Partnership for Human Development, Leesburg, VA, USA and Bissau, Guinea Bissau
| | - Carlito Balé
- International Partnership for Human Development, Leesburg, VA, USA and Bissau, Guinea Bissau
| | - Kenneth Kwan Ho Chui
- Department of Public Health and Community Medicine, Tufts School of Medicine, Boston, MA, USA
| | - Paul Muentener
- Department of Psychology, Tufts University, Medford, MA, USA
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25
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Busch DR, Lin W, Cai C, Cutrone A, Tatka J, Kovarovic BJ, Yodh AG, Floyd TF, Barsi J. Multi-Site Optical Monitoring of Spinal Cord Ischemia during Spine Distraction. J Neurotrauma 2020; 37:2014-2022. [PMID: 32458719 DOI: 10.1089/neu.2020.7012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Optimal surgical management of spine trauma will restore blood flow to the ischemic spinal cord. However, spine stabilization may also further exacerbate injury by inducing ischemia. Current electrophysiological technology is not capable of detecting acute changes in spinal cord blood flow or localizing ischemia. Further, alerts are delayed and unreliable. We developed an epidural optical device capable of directly measuring and immediately detecting changes in spinal cord blood flow using diffuse correlation spectroscopy (DCS). Herein we test the hypothesis that our device can continuously monitor blood flow during spine distraction. Additionally, we demonstrate the ability of our device to monitor multiple sites along the spinal cord and axially resolve changes in spinal cord blood flow. DCS-measured blood flow in the spinal cord was monitored at up to three spatial locations (cranial to, at, and caudal to the distraction site) during surgical distraction in a sheep model. Distraction was halted at 50% of baseline blood flow at the distraction site. We were able to monitor blood flow with DCS in multiple regions of the spinal cord simultaneously at ∼1 Hz. The distraction site had a greater decrement in flow than sites cranial to the injury (median -40 vs. -7%,). This pilot study demonstrated high temporal resolution and the capacity to axially resolve changes in spinal cord blood flow at and remote from the site of distraction. These early results suggest that this technology may assist in the surgical management of spine trauma and in corrective surgery of the spine.
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Affiliation(s)
- David R Busch
- Department of Anesthesiology and Pain Management, University of Texas Southwestern, Dallas, Texas, USA.,Department of Neurology and Neurotherapeutics, University of Texas Southwestern, Dallas, Texas, USA
| | - Wei Lin
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, USA
| | - Chunyu Cai
- Department of Pathology, University of Texas Southwestern, Dallas, Texas, USA
| | - Alissa Cutrone
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Jakub Tatka
- Department of Orthopedic Surgery, Columbia University Medical Center, New York, New York, USA
| | - Brandon J Kovarovic
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, USA
| | - Arjun G Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Thomas F Floyd
- Department of Anesthesiology and Pain Management, University of Texas Southwestern, Dallas, Texas, USA.,Department of Cardiovascular and Thoracic Surgery, University of Texas Southwestern, Dallas, Texas, USA.,Department of Radiology, University of Texas Southwestern, Dallas, Texas, USA
| | - James Barsi
- Department of Orthopedic Surgery, Stony Brook University, Stony Brook, New York, USA
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26
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Optics Based Label-Free Techniques and Applications in Brain Monitoring. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10062196] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Functional near-infrared spectroscopy (fNIRS) has been utilized already around three decades for monitoring the brain, in particular, oxygenation changes in the cerebral cortex. In addition, other optical techniques are currently developed for in vivo imaging and in the near future can be potentially used more in human brain research. This paper reviews the most common label-free optical technologies exploited in brain monitoring and their current and potential clinical applications. Label-free tissue monitoring techniques do not require the addition of dyes or molecular contrast agents. The following optical techniques are considered: fNIRS, diffuse correlations spectroscopy (DCS), photoacoustic imaging (PAI) and optical coherence tomography (OCT). Furthermore, wearable optical brain monitoring with the most common applications is discussed.
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27
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Ling H, Gui Z, Hao H, Shang Y. Enhancement of diffuse correlation spectroscopy tissue blood flow measurement by acoustic radiation force. BIOMEDICAL OPTICS EXPRESS 2020; 11:301-315. [PMID: 32010518 PMCID: PMC6968737 DOI: 10.1364/boe.381757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/09/2019] [Accepted: 12/10/2019] [Indexed: 05/03/2023]
Abstract
The current research on acousto-optic effects focuses on the interactions of acoustic waves with static optical properties rather than dynamic features such as tissue blood flow. Diffuse correlation spectroscopy (DCS) is an emerging technology capable of direct measurements of tissue blood flow by probing the movements of red blood cells (RBCs). In this article, we investigated the relations between the acoustic radiation force (ARF) and ultrasonic patterns by the finite element simulations. Based on the outcomes, we experimentally explored how the ultrasound-generated ARF enhance the DCS data as well as the blood flow measurements. The results yield the optimal pattern to generate ARF and elucidate the relations between the ultrasonic emission and flow elevations. The flow modality combing the DCS with ARF modulations, which was proposed in this study for the first time, would promote disease diagnosis and therapeutic assessment in the situation wherein the blood flow contrast between healthy and pathological tissues is insufficient.
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Affiliation(s)
- Hao Ling
- 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
| | - Huiyan Hao
- Shanxi Provincial Key Laboratory for Biomedical Imaging and Big Data, North University of China, No. 3 Xueyuan Road, Taiyuan 030051, China
| | - 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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28
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Didier KD, Hammer SM, Alexander AM, Caldwell JT, Sutterfield SL, Smith JR, Ade CJ, Barstow TJ. Microvascular blood flow during vascular occlusion tests assessed by diffuse correlation spectroscopy. Exp Physiol 2019; 105:201-210. [DOI: 10.1113/ep087866] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 10/29/2019] [Indexed: 01/13/2023]
Affiliation(s)
- Kaylin D. Didier
- Department of Kinesiology Kansas State University Manhattan KS USA
| | - Shane M. Hammer
- Department of Kinesiology Kansas State University Manhattan KS USA
| | | | | | | | - Joshua R. Smith
- Department of Kinesiology Kansas State University Manhattan KS USA
| | - Carl J. Ade
- Department of Kinesiology Kansas State University Manhattan KS USA
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29
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Tamborini D, Stephens KA, Wu MM, Farzam P, Siegel AM, Shatrovoy O, Blackwell M, Boas DA, Carp SA, Franceschini MA. Portable System for Time-Domain Diffuse Correlation Spectroscopy. IEEE Trans Biomed Eng 2019; 66:3014-3025. [PMID: 30794161 PMCID: PMC7216142 DOI: 10.1109/tbme.2019.2899762] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We introduce a portable system for clinical studies based on time-domain diffuse correlation spectroscopy (DCS). After evaluating different lasers and detectors, the final system is based on a pulsed laser with about 550 ps pulsewidth, a coherence length of 38 mm, and two types of single-photon avalanche diodes (SPAD). The higher efficiency of the red-enhanced SPAD maximizes detection of the collected light, increasing the signal-to-noise ratio, while the better timing response of the CMOS SPAD optimizes the selection of late photons and increases spatial resolution. We discuss component selection and performance, and we present a full characterization of the system, measurement stability, a phantom-based validation study, and preliminary in vivo results collected from the forearms and the foreheads of four healthy subjects. With this system, we are able to resolve blood flow changes 1 cm below the skin surface with improved depth sensitivity and spatial resolution with respect to continuous wave DCS.
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30
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Cheng HH, Ferradal SL, Vyas R, Wigmore D, McDavitt E, Soul JS, Franceschini MA, Newburger JW, Grant PE. Abnormalities in cerebral hemodynamics and changes with surgical intervention in neonates with congenital heart disease. J Thorac Cardiovasc Surg 2019; 159:2012-2021. [PMID: 31685276 DOI: 10.1016/j.jtcvs.2019.08.045] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 07/30/2019] [Accepted: 08/04/2019] [Indexed: 01/24/2023]
Abstract
OBJECTIVE To use novel optical techniques to measure perioperative cerebral hemodynamics of diverse congenital heart disease (CHD) groups (two-ventricle, d-transposition of the great arteries [TGA], and single ventricle [SV]) and (1) compare CHD groups with healthy controls preoperatively and (2) compare preoperative and postoperative values within each CHD group. METHODS Frequency-domain near-infrared spectroscopy and diffuse correlation spectroscopy were used to measure cerebral oxygen saturation, cerebral blood volume, cerebral blood flow index, cerebral oxygen extraction fraction (OEF, calculated using arterial oxygen saturation and cerebral oxygen saturation), and an index of cerebral metabolic rate of oxygen consumption in control and CHD neonates. Preoperative CHD measures were compared with controls. Preoperative and postoperative measures were compared within each CHD group. RESULTS In total, 31 CHD neonates (7 two-ventricle, 11 TGA, 13 SV) and 13 controls were included. Only neonates with SV CHD displayed significantly lower preoperative cerebral blood flow index (P < .04) than controls. TGA and SV groups displayed greater OEF (P < .05) during the preoperative period compared with controls. Compared with the preoperative state, postoperative neonates with TGA had a greater arterial oxygen saturation with lower OEF. CONCLUSIONS Differences in cerebral hemodynamics and oxygen metabolism were observed in diverse CHD groups compared with controls. Increased OEF appears to be a compensatory mechanism in neonates with TGA and SV. Studies are needed to understand the relationship of these metrics to outcome and their potential to guide interventions to improve outcome.
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Affiliation(s)
- Henry H Cheng
- Department of Cardiology, Boston Children's Hospital, Boston, Mass
| | - Silvina L Ferradal
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children's Hospital, Boston, Mass
| | - Rutvi Vyas
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children's Hospital, Boston, Mass
| | - Daniel Wigmore
- Department of Cardiology, Boston Children's Hospital, Boston, Mass
| | - Erica McDavitt
- Department of Cardiology, Boston Children's Hospital, Boston, Mass
| | - Janet S Soul
- Department of Neurology, Boston Children's Hospital, Boston, Mass
| | - Mari A Franceschini
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, Mass
| | - Jane W Newburger
- Department of Cardiology, Boston Children's Hospital, Boston, Mass
| | - P Ellen Grant
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children's Hospital, Boston, Mass.
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31
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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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Lin W, Busch DR, Goh CC, Barsi J, Floyd TF. Diffuse Correlation Spectroscopy Analysis Implemented on a Field Programmable Gate Array. IEEE ACCESS : PRACTICAL INNOVATIONS, OPEN SOLUTIONS 2019; 7:122503-122512. [PMID: 32457822 PMCID: PMC7249994 DOI: 10.1109/access.2019.2938085] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Diffusive correlation spectroscopy (DCS) is an emerging optical technique that measures blood perfusion in deep tissue. In a DCS measurement, temporal changes in the interference pattern of light, which has passed through tissue, are quantified by an autocorrelation function. This autocorrelation function is further parameterized through a non-linear curve fit to a solution to the diffusion equation for coherence transport. The computational load for this non-linear curve fitting is a barrier for deployment of DCS for clinical use, where real-time results, as well as instrument size and simplicity, are important considerations. We have mitigated this computational bottleneck through development of a hardware analyzer for DCS. This analyzer implements the DCS curving fitting algorithm on digital logic circuit using Field Programmable Gate Array (FPGA) technology. The FPGA analyzer is more efficient than a typical software analysis solution. The analyzer module can be easily duplicated for processing multiple channels of DCS data in real-time. We have demonstrated the utility of this analyzer in pre-clinical large animal studies of spinal cord ischemia. In combination with previously described FPGA implementations of auto-correlators, this hardware analyzer can provide a complete device-on-a-chip solution for DCS signal processing. Such a component will enable new DCS applications demanding mobility and real-time processing.
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Affiliation(s)
- Wei Lin
- Stony Brook University, Stony Brook, NY 11794 USA
| | - David R. Busch
- University of Texas Southwestern, Dallas TX 75390 80523 USA
| | | | - James Barsi
- Stony Brook University, Stony Brook, NY 11794 USA
| | - Thomas F. Floyd
- Stony Brook University, Stony Brook, NY 11794 USA
- University of Texas Southwestern, Dallas TX 75390 80523 USA
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Schytz HW, Amin FM, Selb J, Boas DA. Non-invasive methods for measuring vascular changes in neurovascular headaches. J Cereb Blood Flow Metab 2019; 39:633-649. [PMID: 28782410 PMCID: PMC6446419 DOI: 10.1177/0271678x17724138] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Vascular changes during spontaneous headache attacks have been studied over the last 30 years. The interest in cerebral vessels in headache research was initially due to the hypothesis of cerebral vessels as the pain source. Here, we review the knowledge gained by measuring the cerebral vasculature during spontaneous primary headache attacks with the use of single photon emission tomography (SPECT), positron emission tomography (PET), magnetic resonance imaging (MRA) and transcranial Doppler (TCD). Furthermore, the use of near-infrared spectroscopy in headache research is reviewed. Existing TCD studies of migraine and other headache disorders do not provide solid evidence for cerebral blood flow velocity changes during spontaneous attacks of migraine headache. SPECT studies have clearly shown cortical vascular changes following migraine aura and the differences between migraine with aura compared to migraine without aura. PET studies have shown focal activation in brain structures related to headache, but whether the changes are specific to different primary headaches have yet to be demonstrated. MR angiography has shown precise changes in large cerebral vessels during spontaneous migraine without aura attacks. Future development in more precise imaging methods may further elucidate the pathophysiological mechanisms in primary headaches.
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Affiliation(s)
- Henrik W Schytz
- 1 Danish Headache Center and Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark
| | - Faisal M Amin
- 1 Danish Headache Center and Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Copenhagen, Denmark
| | - Juliette Selb
- 2 Department of Radiology, MGH/HST Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, USA
| | - David A Boas
- 2 Department of Radiology, MGH/HST Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, USA
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Pham T, Tgavalekos K, Sassaroli A, Blaney G, Fantini S. Quantitative measurements of cerebral blood flow with near-infrared spectroscopy. BIOMEDICAL OPTICS EXPRESS 2019; 10:2117-2134. [PMID: 31061774 PMCID: PMC6484993 DOI: 10.1364/boe.10.002117] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/07/2019] [Accepted: 03/20/2019] [Indexed: 05/29/2023]
Abstract
We propose a new near-infrared spectroscopy (NIRS) method for quantitative measurements of cerebral blood flow (CBF). Because this method uses concepts of coherent hemodynamics spectroscopy (CHS), we identify this new method with the acronym NIRS-CHS. We tested this method on the prefrontal cortex of six healthy human subjects during mean arterial pressure (MAP) transients induced by the rapid deflation of pneumatic thigh cuffs. A comparison of CBF dynamics measured with NIRS-CHS and with diffuse correlation spectroscopy (DCS) showed a good agreement for characteristic times of the CBF transient. We also report absolute measurements of baseline CBF with NIRS-CHS (69 ± 6 ml/100g/min over the six subjects). NIRS-CHS can provide more accurate measurements of CBF with respect to previously reported NIRS surrogates of CBF.
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Affiliation(s)
- Thao Pham
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| | - Kristen Tgavalekos
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| | - Angelo Sassaroli
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| | - Giles Blaney
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| | - Sergio Fantini
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
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Vasung L, Abaci Turk E, Ferradal SL, Sutin J, Stout JN, Ahtam B, Lin PY, Grant PE. Exploring early human brain development with structural and physiological neuroimaging. Neuroimage 2019; 187:226-254. [PMID: 30041061 PMCID: PMC6537870 DOI: 10.1016/j.neuroimage.2018.07.041] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 07/16/2018] [Accepted: 07/16/2018] [Indexed: 12/11/2022] Open
Abstract
Early brain development, from the embryonic period to infancy, is characterized by rapid structural and functional changes. These changes can be studied using structural and physiological neuroimaging methods. In order to optimally acquire and accurately interpret this data, concepts from adult neuroimaging cannot be directly transferred. Instead, one must have a basic understanding of fetal and neonatal structural and physiological brain development, and the important modulators of this process. Here, we first review the major developmental milestones of transient cerebral structures and structural connectivity (axonal connectivity) followed by a summary of the contributions from ex vivo and in vivo MRI. Next, we discuss the basic biology of neuronal circuitry development (synaptic connectivity, i.e. ensemble of direct chemical and electrical connections between neurons), physiology of neurovascular coupling, baseline metabolic needs of the fetus and the infant, and functional connectivity (defined as statistical dependence of low-frequency spontaneous fluctuations seen with functional magnetic resonance imaging (fMRI)). The complementary roles of magnetic resonance imaging (MRI), electroencephalography (EEG), magnetoencephalography (MEG), and near-infrared spectroscopy (NIRS) are discussed. We include a section on modulators of brain development where we focus on the placenta and emerging placental MRI approaches. In each section we discuss key technical limitations of the imaging modalities and some of the limitations arising due to the biology of the system. Although neuroimaging approaches have contributed significantly to our understanding of early brain development, there is much yet to be done and a dire need for technical innovations and scientific discoveries to realize the future potential of early fetal and infant interventions to avert long term disease.
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Affiliation(s)
- Lana Vasung
- Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
| | - Esra Abaci Turk
- Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
| | - Silvina L Ferradal
- Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
| | - Jason Sutin
- Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
| | - Jeffrey N Stout
- Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
| | - Banu Ahtam
- Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
| | - Pei-Yi Lin
- Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
| | - P Ellen Grant
- Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
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Busch DR, Balu R, Baker WB, Guo W, He L, Diop M, Milej D, Kavuri V, Amendolia O, St Lawrence K, Yodh AG, Kofke WA. Detection of Brain Hypoxia Based on Noninvasive Optical Monitoring of Cerebral Blood Flow with Diffuse Correlation Spectroscopy. Neurocrit Care 2019; 30:72-80. [PMID: 30030667 PMCID: PMC6528475 DOI: 10.1007/s12028-018-0573-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Diffuse correlation spectroscopy (DCS) noninvasively permits continuous, quantitative, bedside measurements of cerebral blood flow (CBF). To test whether optical monitoring (OM) can detect decrements in CBF producing cerebral hypoxia, we applied the OM technique continuously to probe brain-injured patients who also had invasive brain tissue oxygen (PbO2) monitors. METHODS Comatose patients with a Glasgow Coma Score (GCS) < 8) were enrolled in an IRB-approved protocol after obtaining informed consent from the legally authorized representative. Patients underwent 6-8 h of daily monitoring. Brain PbO2 was measured with a Clark electrode. Absolute CBF was monitored with DCS, calibrated by perfusion measurements based on intravenous indocyanine green bolus administration. Variation of optical CBF and mean arterial pressure (MAP) from baseline was measured during periods of brain hypoxia (defined as a drop in PbO2 below 19 mmHg for more than 6 min from baseline (PbO2 > 21 mmHg). In a secondary analysis, we compared optical CBF and MAP during randomly selected 12-min periods of "normal" (> 21 mmHg) and "low" (< 19 mmHg) PbO2. Receiver operator characteristic (ROC) and logistic regression analysis were employed to assess the utility of optical CBF, MAP, and the two-variable combination, for discrimination of brain hypoxia from normal brain oxygen tension. RESULTS Seven patients were enrolled and monitored for a total of 17 days. Baseline-normalized MAP and CBF significantly decreased during brain hypoxia events (p < 0.05). Through use of randomly selected, temporally sparse windows of low and high PbO2, we observed that both MAP and optical CBF discriminated between periods of brain hypoxia and normal brain oxygen tension (ROC AUC 0.761, 0.762, respectively). Further, combining these variables using logistic regression analysis markedly improved the ability to distinguish low- and high-PbO2 epochs (AUC 0.876). CONCLUSIONS The data suggest optical techniques may be able to provide continuous individualized CBF measurement to indicate occurrence of brain hypoxia and guide brain-directed therapy.
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Affiliation(s)
- David R Busch
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
- Departments of Anesthesiology and Pain Management & Neurology and Neurotherapeutics, University of Texas, Southwestern Medical Center, Dallas, TX, USA
| | - Ramani Balu
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - Wesley B Baker
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, 19104, PA, USA
| | - Wensheng Guo
- Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Lian He
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
| | - Mamadou Diop
- Department of Medical Biophysics, Lawson Health Research Institute, University of Western Ontario, London, Canada
| | - Daniel Milej
- Department of Medical Biophysics, Lawson Health Research Institute, University of Western Ontario, London, Canada
| | - Venkaiah Kavuri
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
| | - Olivia Amendolia
- Neurosurgery Clinical Research Division, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Keith St Lawrence
- Department of Medical Biophysics, Lawson Health Research Institute, University of Western Ontario, London, Canada
| | - Arjun G Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
| | - W Andrew Kofke
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, 19104, PA, USA.
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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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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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Selb J, Wu KC, Sutin J, Lin PY(I, Farzam P, Bechek S, Shenoy A, Patel AB, Boas DA, Franceschini MA, Rosenthal ES. Prolonged monitoring of cerebral blood flow and autoregulation with diffuse correlation spectroscopy in neurocritical care patients. NEUROPHOTONICS 2018; 5:045005. [PMID: 30450363 PMCID: PMC6233866 DOI: 10.1117/1.nph.5.4.045005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 09/24/2018] [Indexed: 05/13/2023]
Abstract
Monitoring of cerebral blood flow (CBF) and autoregulation are essential components of neurocritical care, but continuous noninvasive methods for CBF monitoring are lacking. Diffuse correlation spectroscopy (DCS) is a noninvasive diffuse optical modality that measures a CBF index ( CBF i ) in the cortex microvasculature by monitoring the rapid fluctuations of near-infrared light diffusing through moving red blood cells. We tested the feasibility of monitoring CBF i with DCS in at-risk patients in the Neurosciences Intensive Care Unit. DCS data were acquired continuously for up to 20 h in six patients with aneurysmal subarachnoid hemorrhage, as permitted by clinical care. Mean arterial blood pressure was recorded synchronously, allowing us to derive autoregulation curves and to compute an autoregulation index. The autoregulation curves suggest disrupted cerebral autoregulation in most patients, with the severity of disruption and the limits of preserved autoregulation varying between subjects. Our findings suggest the potential of the DCS modality for noninvasive, long-term monitoring of cerebral perfusion, and autoregulation.
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Affiliation(s)
- Juliette Selb
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Kuan-Cheng Wu
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Jason Sutin
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Pei-Yi (Ivy) Lin
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Parisa Farzam
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Sophia Bechek
- Massachusetts General Hospital, Department of Neurology, Boston, Massachusetts, United States
| | - Apeksha Shenoy
- Massachusetts General Hospital, Department of Neurology, Boston, Massachusetts, United States
| | - Aman B. Patel
- Massachusetts General Hospital, Department of Neurology, Boston, Massachusetts, United States
| | - David A. Boas
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Maria Angela Franceschini
- Massachusetts General Hospital, Optics at Martinos, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
- Address all correspondence to: Maria Angela Franceschini, E-mail:
| | - Eric S. Rosenthal
- Massachusetts General Hospital, Department of Neurology, Boston, Massachusetts, United States
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Ichinose M, Nakabayashi M, Ono Y. Sympathoexcitation constrains vasodilation in the human skeletal muscle microvasculature during postocclusive reactive hyperemia. Am J Physiol Heart Circ Physiol 2018; 315:H242-H253. [DOI: 10.1152/ajpheart.00010.2018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We used diffuse correlation spectroscopy to investigate sympathetic vasoconstriction, local vasodilation, and integration of these two responses in the skeletal muscle microvasculature of 20 healthy volunteers. Diffuse correlation spectroscopy probes were placed on the flexor carpi radialis muscle or vastus lateralis muscle, and a blood flow index was derived continuously. We measured hemodynamic responses during sympathoexcitation induced by forehead cooling, after which the effects of the increased sympathetic tone on vasodilatory responses during postocclusive reactive hyperemia (PORH) were examined. PORH was induced by releasing arterial occlusion (3 min) in an arm or leg. To increase sympathetic tone during PORH, forehead cooling was begun 60 s before the occlusion release and ended 60 s after the release. During forehead cooling, mean arterial pressure rose significantly and was sustained at an elevated level. Significant vasoconstriction and decreases in blood flow index followed by gradual blunting of the vasoconstriction also occurred. The time course of these responses is in good agreement with previous observations in animals. The acute sympathoexcitation diminished the peak vasodilation during PORH only in the vastus lateralis muscle, but it hastened the decline in vasodilation after the peak in both the flexor carpi radialis muscle and vastus lateralis muscle. Consequently, the total vasodilatory response assessed as the area of the vascular conductance during the first minute of PORH was significantly diminished in both regions. We conclude that, in humans, the integrated effects of sympathetic vasoconstriction and local vasodilation have an important role in vascular regulation and control of perfusion in the skeletal muscle microcirculation. NEW & NOTEWORTHY We used diffuse correlation spectroscopy to demonstrate that acute sympathoexcitation constrains local vasodilation in the human skeletal muscle microvasculature during postocclusive reactive hyperemia. This finding indicates that integration of sympathetic vasoconstriction and local vasodilation is importantly involved in vascular regulation and the control of perfusion of the skeletal muscle microcirculation in humans.
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Affiliation(s)
- Masashi Ichinose
- Human Integrative Physiology Laboratory, School of Business Administration, Meiji University, Tokyo, Japan
| | - Mikie Nakabayashi
- Graduate School of Science and Technology, Meiji University, Kanagawa, Japan
| | - Yumie Ono
- Department of Electronics and Bioinformatics, School of Science and Technology, Meiji University, Kanagawa, Japan
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Busch DR, Davis J, Kogler A, Galler RM, Parthasarathy AB, Yodh AG, Floyd TF. Laser safety in fiber-optic monitoring of spinal cord hemodynamics: a preclinical evaluation. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-9. [PMID: 29923371 PMCID: PMC8357330 DOI: 10.1117/1.jbo.23.6.065003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 05/30/2018] [Indexed: 05/02/2023]
Abstract
The prevention and treatment of spinal cord injury are focused upon the maintenance of spinal cord blood flow, yet no technology exists to monitor spinal cord ischemia. We recently demonstrated continuous monitoring of spinal cord ischemia with diffuse correlation and optical spectroscopies using an optical probe. Prior to clinical translation of this technology, it is critically important to demonstrate the safety profile of spinal cord exposure to the required light. To our knowledge, this is the first report of in situ safety testing of such a monitor. We expose the spinal cord to laser light utilizing a custom fiber-optic epidural probe in a survival surgery model (11 adult Dorset sheep). We compare the tissue illumination from our instrument with the American National Standards Institute maximum permissible exposures. We experimentally evaluate neurological and pathological outcomes of the irradiated sheep associated with prolonged exposure to the laser source and evaluate heating in ex vivo spinal cord samples. Spinal cord tissue was exposed to light levels at ∼18 × the maximum permissible exposure for the eye and ∼ ( 1 / 3 ) × for the skin. Multidisciplinary testing revealed no functional neurological sequelae, histopathologic evidence of laser-related injury to the spinal cord, or significant temperature changes in ex vivo samples. Low tissue irradiance and the lack of neurological, pathological, and temperature changes upon prolonged exposure to the laser source offer evidence that spinal cord tissues can be monitored safely with near-infrared optical probes placed within the epidural space.
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Affiliation(s)
- David R. Busch
- University of Texas Southwestern, Department of Anesthesiology and Pain Management, Dallas Texas, United States
- University of Texas Southwestern, Department of Neurology and Neurotherapeutics, Dallas, Texas, United States
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
- Address all correspondence to: David R. Busch, E-mail: ; Thomas F. Floyd, E-mail:
| | - James Davis
- Stony Brook University Medical Center, Department of Pathology, Stony Brook, New York, United States
| | - Angela Kogler
- Stony Brook University Medical Center, Department of Anesthesiology, Stony Brook, New York, United States
- Stony Brook University, Department of Biomedical Engineering, Stony Brook, New York, United States
| | - Robert M. Galler
- Stony Brook University Medical Center, Department of Neurosurgery, Stony Brook, New York, United States
| | - Ashwin B. Parthasarathy
- University of South Florida, Department of Electrical Engineering, Tampa, Florida, United States
| | - Arjun G. Yodh
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
| | - Thomas F. Floyd
- University of Texas Southwestern, Department of Anesthesiology and Pain Management, Dallas Texas, United States
- Address all correspondence to: David R. Busch, E-mail: ; Thomas F. Floyd, E-mail:
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Hammer SM, Alexander AM, Didier KD, Smith JR, Caldwell JT, Sutterfield SL, Ade CJ, Barstow TJ. The noninvasive simultaneous measurement of tissue oxygenation and microvascular hemodynamics during incremental handgrip exercise. J Appl Physiol (1985) 2018; 124:604-614. [DOI: 10.1152/japplphysiol.00815.2017] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Limb blood flow increases linearly with exercise intensity; however, invasive measurements of muscle microvascular blood flow during incremental exercise have demonstrated submaximal plateaus. We tested the hypotheses that 1) brachial artery blood flow (Q̇BA) would increase with increasing exercise intensity until task failure, 2) blood flow index of the flexor digitorum superficialis (BFIFDS) measured noninvasively via diffuse correlation spectroscopy would plateau at a submaximal work rate, and 3) muscle oxygenation characteristics (total-[heme], deoxy-[heme], and percentage saturation) measured noninvasively with near-infrared spectroscopy would demonstrate a plateau at a similar work rate as BFIFDS. Sixteen subjects (23.3 ± 3.9 yr, 170.8 ± 1.9 cm, 72.8 ± 3.4 kg) participated in this study. Peak power (Ppeak) was determined for each subject (1.8 ± 0.4 W) via an incremental handgrip exercise test. Q̇BA, BFIFDS, total-[heme], deoxy-[heme], and percentage saturation were measured during each stage of the exercise test. On a subsequent testing day, muscle activation measurements of the FDS (RMSFDS) were collected during each stage of an identical incremental handgrip exercise test via electromyography from a subset of subjects ( n = 7). Q̇BA increased with exercise intensity until the final work rate transition ( P < 0.05). No increases in BFIFDS or muscle oxygenation characteristics were observed at exercise intensities greater than 51.5 ± 22.9% of Ppeak. No submaximal plateau in RMSFDS was observed. Whereas muscle activation of the FDS increased until task failure, noninvasively measured indices of perfusive and diffusive muscle microvascular oxygen delivery demonstrated submaximal plateaus. NEW & NOTEWORTHY Invasive measurements of muscle microvascular blood flow during incremental exercise have demonstrated submaximal plateaus. We demonstrate that indices of perfusive and diffusive microvascular oxygen transport to skeletal muscle, measured completely noninvasively, plateau at submaximal work rates during incremental exercise, even though limb blood flow and muscle recruitment continued to increase.
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Affiliation(s)
- Shane M. Hammer
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | | | - Kaylin D. Didier
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Joshua R. Smith
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Jacob T. Caldwell
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | | | - Carl J. Ade
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Thomas J. Barstow
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
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43
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Proctor AR, Ramirez GA, Han S, Liu Z, Bubel TM, Choe R. Validation of diffuse correlation spectroscopy sensitivity to nicotinamide-induced blood flow elevation in the murine hindlimb using the fluorescent microsphere technique. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-9. [PMID: 29595019 PMCID: PMC5873645 DOI: 10.1117/1.jbo.23.3.035006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/06/2018] [Indexed: 05/15/2023]
Abstract
Nicotinamide has been shown to affect blood flow in both tumor and normal tissues, including skeletal muscle. Intraperitoneal injection of nicotinamide was used as a simple intervention to test the sensitivity of noninvasive diffuse correlation spectroscopy (DCS) to changes in blood flow in the murine left quadriceps femoris skeletal muscle. DCS was then compared with the gold-standard fluorescent microsphere (FM) technique for validation. The nicotinamide dose-response experiment showed that relative blood flow measured by DCS increased following treatment with 500- and 1000-mg / kg nicotinamide. The DCS and FM technique comparison showed that blood flow index measured by DCS was correlated with FM counts quantified by image analysis. The results of this study show that DCS is sensitive to nicotinamide-induced blood flow elevation in the murine left quadriceps femoris. Additionally, the results of the comparison were consistent with similar studies in higher-order animal models, suggesting that mouse models can be effectively employed to investigate the utility of DCS for various blood flow measurement applications.
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Affiliation(s)
- Ashley R. Proctor
- University of Rochester, Department of Biomedical Engineering, Rochester, New York, United States
| | - Gabriel A. Ramirez
- University of Rochester, Department of Biomedical Engineering, Rochester, New York, United States
| | - Songfeng Han
- University of Rochester, Institute of Optics, Rochester, New York, United States
| | - Ziping Liu
- University of Rochester, Department of Biomedical Engineering, Rochester, New York, United States
| | - Tracy M. Bubel
- University of Rochester, Center for Visual Science, Rochester, New York, United States
| | - Regine Choe
- University of Rochester, Department of Biomedical Engineering, Rochester, New York, United States
- University of Rochester, Department of Electrical and Computer Engineering, Rochester, New York, United States
- Address all correspondence to: Regine Choe, E-mail:
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44
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Li J, Poon CS, Kress J, Rohrbach DJ, Sunar U. Resting-state functional connectivity measured by diffuse correlation spectroscopy. JOURNAL OF BIOPHOTONICS 2018; 11. [PMID: 28708329 DOI: 10.1002/jbio.201700165] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 06/29/2017] [Indexed: 05/17/2023]
Abstract
Near-infrared diffuse correlation spectroscopy (DCS) is used to record spontaneous cerebral blood flow fluctuations in the frontal cortex. Nine adult subjects participated in the experiments, in which 8-minute spontaneous fluctuations were simultaneously recorded from the left and right dorsolateral and inferior frontal regions. Resting-state functional connectivity (RSFC) was measured by the temporal correlation of the low frequency fluctuations. Our data shows the RSFC within the dorsolateral region is significantly stronger than that between the inferior and dorsolateral regions, in line with previous observations with functional near-infrared spectroscopy. This indicates that DCS is capable of investigating brain functional connectivity in terms of cerebral blood flow.
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Affiliation(s)
- Jun Li
- Department of Biomedical, Industrial and Human Factors, Wright State University, Dayton, Ohio
| | - Chien-Sing Poon
- Department of Biomedical, Industrial and Human Factors, Wright State University, Dayton, Ohio
| | - Jeremy Kress
- Department of Biomedical, Industrial and Human Factors, Wright State University, Dayton, Ohio
| | - Daniel J Rohrbach
- Department of Biomedical, Industrial and Human Factors, Wright State University, Dayton, Ohio
| | - Ulas Sunar
- Department of Biomedical, Industrial and Human Factors, Wright State University, Dayton, Ohio
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45
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Li J, Qiu L, Poon CS, Sunar U. Analytical models for time-domain diffuse correlation spectroscopy for multi-layer and heterogeneous turbid media. BIOMEDICAL OPTICS EXPRESS 2017; 8:5518-5532. [PMID: 29296485 PMCID: PMC5745100 DOI: 10.1364/boe.8.005518] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 10/24/2017] [Accepted: 10/24/2017] [Indexed: 05/18/2023]
Abstract
A novel approach for time-domain diffuse correlation spectroscopy (TD-DCS) has been recently proposed, which has the unique advantage by simultaneous measurements of optical and dynamical properties in a scattering medium. In this study, analytical models for calculating the time-resolved electric-field autocorrelation function is presented for a multi-layer turbid sample, as well as a semi-infinite medium embedded with a small dynamic heterogeneity. To verify the analytical models, we used Monte Carlo simulations, which demonstrated that the theoretical prediction for the time-resolved autocorrelation function was highly consistent with the Monte Carlo simulation, validating the proposed analytical models. Using these analytical models, we also showed that TD-DCS has a higher sensitivity compared to conventional continuous-wave (CW) DCS for detecting the deeper dynamics. The presented analytical models and simulations can be utilized for quantification of optical and dynamical properties from future TD-DCS experimental data as well as for optimization of the experimental design to achieve maximum contrast for deep tissue dynamics.
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Affiliation(s)
- Jun Li
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, National Center for International Research on Green Optoelectronics, MOE International Laboratory for Optical Information Technologies, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, China
- Department of Biomedical, Industrial and Human Factors Engineering, Wright State University, Dayton, OH 45435, USA
- These authors contributed equally
| | - Lina Qiu
- Dipartimento di Fisica, Politecnico di Milano, Milan, Italy
- These authors contributed equally
| | - Chien-Sing Poon
- Department of Biomedical, Industrial and Human Factors Engineering, Wright State University, Dayton, OH 45435, USA
| | - Ulas Sunar
- Department of Biomedical, Industrial and Human Factors Engineering, Wright State University, Dayton, OH 45435, USA
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46
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Farzam P, Buckley EM, Lin PY, Hagan K, Grant PE, Inder TE, Carp SA, Franceschini MA. Shedding light on the neonatal brain: probing cerebral hemodynamics by diffuse optical spectroscopic methods. Sci Rep 2017; 7:15786. [PMID: 29150648 PMCID: PMC5693925 DOI: 10.1038/s41598-017-15995-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 11/03/2017] [Indexed: 11/24/2022] Open
Abstract
Investigating the cerebral physiology of healthy term newborns' brains is important for better understanding perinatal brain injuries, of which the most common etiologies are hypoxia and ischemia. Hence, cerebral blood flow and cerebral oxygenation are important biomarkers of brain health. In this study, we employed a hybrid diffuse optical system consisting of diffuse correlation spectroscopy (DCS) and frequency-domain near infrared spectroscopy (FDNIRS) to measure hemoglobin concentration, oxygen saturation, and indices of cerebral blood flow and metabolism. We measured 30 term infants to assess the optical and physiological characteristics of the healthy neonatal brain in the frontal, temporal, and parietal lobes. We observed higher metabolism in the right hemisphere compared to the left and a positive correlation between gestational age and the level of cerebral hemoglobin concentration, blood volume, and oxygen saturation. Moreover, we observed higher cerebral blood flow and lower oxygen saturation in females compared to males. The delayed maturation in males and the sexual dimorphism in cerebral hemodynamics may explain why males are more vulnerable to perinatal brain injuries than females.
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Affiliation(s)
- Parisa Farzam
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA.
| | - Erin M Buckley
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
- Georgia Institute of Technology, Atlanta, GA, 30322, USA
| | - Pei-Yi Lin
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
| | - Katherine Hagan
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
| | - P Ellen Grant
- Fetal-Neonatal Neuroimaging and Developmental Science Center, Division of Newborn Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Terrie Eleanor Inder
- Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Stefan A Carp
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
| | - Maria Angela Franceschini
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
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47
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Shedding light on the neonatal brain: probing cerebral hemodynamics by diffuse optical spectroscopic methods. Sci Rep 2017. [PMID: 29150648 DOI: 10.1038/s41598‐017‐15995‐1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Investigating the cerebral physiology of healthy term newborns' brains is important for better understanding perinatal brain injuries, of which the most common etiologies are hypoxia and ischemia. Hence, cerebral blood flow and cerebral oxygenation are important biomarkers of brain health. In this study, we employed a hybrid diffuse optical system consisting of diffuse correlation spectroscopy (DCS) and frequency-domain near infrared spectroscopy (FDNIRS) to measure hemoglobin concentration, oxygen saturation, and indices of cerebral blood flow and metabolism. We measured 30 term infants to assess the optical and physiological characteristics of the healthy neonatal brain in the frontal, temporal, and parietal lobes. We observed higher metabolism in the right hemisphere compared to the left and a positive correlation between gestational age and the level of cerebral hemoglobin concentration, blood volume, and oxygen saturation. Moreover, we observed higher cerebral blood flow and lower oxygen saturation in females compared to males. The delayed maturation in males and the sexual dimorphism in cerebral hemodynamics may explain why males are more vulnerable to perinatal brain injuries than females.
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48
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Carp SA, Farzam P, Redes N, Hueber DM, Franceschini MA. Combined multi-distance frequency domain and diffuse correlation spectroscopy system with simultaneous data acquisition and real-time analysis. BIOMEDICAL OPTICS EXPRESS 2017; 8:3993-4006. [PMID: 29026684 PMCID: PMC5611918 DOI: 10.1364/boe.8.003993] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 07/29/2017] [Accepted: 07/29/2017] [Indexed: 05/19/2023]
Abstract
Frequency domain near infrared spectroscopy (FD-NIRS) and diffuse correlation spectroscopy (DCS) have emerged as synergistic techniques for the non-invasive assessment of tissue health. Combining FD-NIRS oximetry with DCS measures of blood flow, the tissue oxygen metabolic rate can be quantified, a parameter more closely linked to underlying physiology and pathology than either NIRS or DCS estimates alone. Here we describe the first commercially available integrated instrument, called the "MetaOx", designed to enable simultaneous FD-NIRS and DCS measurements at rates of 10 + Hz, and offering real-time data evaluation. We show simultaneously acquired characterization data demonstrating performance equivalent to individual devices and sample in vivo measurements of pulsation resolved blood flow, forearm occlusion hemodynamic changes and muscle oxygen metabolic rate monitoring during stationary bike exercise.
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Affiliation(s)
- Stefan A. Carp
- Harvard Medical School, Massachusetts General Hospital, Martinos Center for Biomedical Imaging, 149 13th St., Charlestown, MA 02129, USA
| | - Parisa Farzam
- Harvard Medical School, Massachusetts General Hospital, Martinos Center for Biomedical Imaging, 149 13th St., Charlestown, MA 02129, USA
| | - Norin Redes
- ISS Inc., 1602 Newton Drive, Champaign, IL 61822, USA
| | | | - Maria Angela Franceschini
- Harvard Medical School, Massachusetts General Hospital, Martinos Center for Biomedical Imaging, 149 13th St., Charlestown, MA 02129, USA
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49
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Sakadžić S, Boas DA, Carp S. Theoretical model of blood flow measurement by diffuse correlation spectroscopy. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:27006. [PMID: 28241276 PMCID: PMC5325034 DOI: 10.1117/1.jbo.22.2.027006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 01/30/2017] [Indexed: 05/03/2023]
Abstract
Diffuse correlation spectroscopy (DCS) is a noninvasive method to quantify tissue perfusion from measurements of the intensity temporal autocorrelation function of diffusely scattered light. However, DCS autocorrelation function measurements in tissue better match theoretical predictions based on the diffusive motion of the scatterers than those based on a model where the advective nature of blood flow dominates the stochastic properties of the scattered light. We have recently shown using Monte Carlo (MC) simulations and assuming a simplistic vascular geometry and laminar flow profile that the diffusive nature of the DCS autocorrelation function decay is likely a result of the shear-induced diffusion of the red blood cells. Here, we provide theoretical derivations supporting and generalizing the previous MC results. Based on the theory of diffusing-wave spectroscopy, we derive an expression for the autocorrelation function along the photon path through a vessel that takes into account both diffusive and advective scatterer motion, and we provide the solution for the DCS autocorrelation function in a semi-infinite geometry. We also derive the correlation diffusion and correlation transfer equation, which can be applied for an arbitrary sample geometry. Further, we propose a method to take into account realistic vascular morphology and flow profile.
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Affiliation(s)
- Sava Sakadžić
- Massachusetts General Hospital and Harvard Medical School, Optics Division, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
- Address all correspondence to: Sava Sakadžić, E-mail:
| | - David A. Boas
- Massachusetts General Hospital and Harvard Medical School, Optics Division, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
| | - Stefan Carp
- Massachusetts General Hospital and Harvard Medical School, Optics Division, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts, United States
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50
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Sutin J, Zimmerman B, Tyulmankov D, Tamborini D, Wu KC, Selb J, Gulinatti A, Rech I, Tosi A, Boas DA, Franceschini MA. Time-domain diffuse correlation spectroscopy. OPTICA 2016; 3:1006-1013. [PMID: 28008417 PMCID: PMC5166986 DOI: 10.1364/optica.3.001006] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Physiological monitoring of oxygen delivery to the brain has great significance for improving the management of patients at risk for brain injury. Diffuse correlation spectroscopy (DCS) is a rapidly growing optical technology able to non-invasively assess the blood flow index (BFi) at the bedside. The current limitations of DCS are the contamination introduced by extracerebral tissue and the need to know the tissue's optical properties to correctly quantify the BFi. To overcome these limitations, we have developed a new technology for time-resolved diffuse correlation spectroscopy. By operating DCS in the time domain (TD-DCS), we are able to simultaneously acquire the temporal point-spread function to quantify tissue optical properties and the autocorrelation function to quantify the BFi. More importantly, by applying time-gated strategies to the DCS autocorrelation functions, we are able to differentiate between short and long photon paths through the tissue and determine the BFi for different depths. Here, we present the novel device and we report the first experiments in tissue-like phantoms and in rodents. The TD-DCS method opens many possibilities for improved non-invasive monitoring of oxygen delivery in humans.
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Affiliation(s)
- Jason Sutin
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Bernhard Zimmerman
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Danil Tyulmankov
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Davide Tamborini
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
- Dipartimento di Elettronica, Informazione e Bioingegneria at Politecnico di Milano, Milano, Italy
| | - Kuan Cheng Wu
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Juliette Selb
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Angelo Gulinatti
- Dipartimento di Elettronica, Informazione e Bioingegneria at Politecnico di Milano, Milano, Italy
| | - Ivan Rech
- Dipartimento di Elettronica, Informazione e Bioingegneria at Politecnico di Milano, Milano, Italy
| | - Alberto Tosi
- Dipartimento di Elettronica, Informazione e Bioingegneria at Politecnico di Milano, Milano, Italy
| | - David A. Boas
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Maria Angela Franceschini
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
- Corresponding author:
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