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Kostoglou K, Bello-Robles F, Brassard P, Chacon M, Claassen JA, Czosnyka M, Elting JW, Hu K, Labrecque L, Liu J, Marmarelis VZ, Payne SJ, Shin DC, Simpson D, Smirl J, Panerai RB, Mitsis GD. Time-domain methods for quantifying dynamic cerebral blood flow autoregulation: Review and recommendations. A white paper from the Cerebrovascular Research Network (CARNet). J Cereb Blood Flow Metab 2024:271678X241249276. [PMID: 38688529 DOI: 10.1177/0271678x241249276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
Cerebral Autoregulation (CA) is an important physiological mechanism stabilizing cerebral blood flow (CBF) in response to changes in cerebral perfusion pressure (CPP). By maintaining an adequate, relatively constant supply of blood flow, CA plays a critical role in brain function. Quantifying CA under different physiological and pathological states is crucial for understanding its implications. This knowledge may serve as a foundation for informed clinical decision-making, particularly in cases where CA may become impaired. The quantification of CA functionality typically involves constructing models that capture the relationship between CPP (or arterial blood pressure) and experimental measures of CBF. Besides describing normal CA function, these models provide a means to detect possible deviations from the latter. In this context, a recent white paper from the Cerebrovascular Research Network focused on Transfer Function Analysis (TFA), which obtains frequency domain estimates of dynamic CA. In the present paper, we consider the use of time-domain techniques as an alternative approach. Due to their increased flexibility, time-domain methods enable the mitigation of measurement/physiological noise and the incorporation of nonlinearities and time variations in CA dynamics. Here, we provide practical recommendations and guidelines to support researchers and clinicians in effectively utilizing these techniques to study CA.
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Affiliation(s)
- Kyriaki Kostoglou
- Department of Electrical and Computer Engineering, McGill University, Montreal, QC, Canada
- Institute of Neural Engineering, Graz University of Technology, Graz, Austria
| | - Felipe Bello-Robles
- Departamento de Ingeniería Informática, Universidad de Santiago de Chile, Santiago, Chile
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Quebec, QC, Canada
- Research Center of the Institut universitaire de cardiologie et de pneumologie de Québec, Quebec, QC, Canada
| | - Max Chacon
- Departamento de Ingeniería Informática, Universidad de Santiago de Chile, Santiago, Chile
| | - Jurgen Ahr Claassen
- Department of Geriatrics, Radboud University Medical Center, Research Institute for Medical Innovation and Donders Institute, Nijmegen, The Netherlands
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM), Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Marek Czosnyka
- Department of Clinical Neurosciences, Neurosurgery Department, University of Cambridge, Cambridge, UK
| | - Jan-Willem Elting
- Department of Neurology and Clinical Neurophysiology, University Medical Center Groningen, Groningen, The Netherlands
| | - Kun Hu
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
| | - Lawrence Labrecque
- Department of Kinesiology, Faculty of Medicine, Université Laval, Quebec, QC, Canada
- Research Center of the Institut universitaire de cardiologie et de pneumologie de Québec, Quebec, QC, Canada
| | - Jia Liu
- Laboratory for Engineering and Scientific Computing, Institute of Advanced Computing and Digital Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Vasilis Z Marmarelis
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, USA
| | - Stephen J Payne
- Institute of Applied Mechanics, National Taiwan University, Taipei, Taiwan
| | - Dae Cheol Shin
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, USA
| | - David Simpson
- Institute of Sound and Vibration Research, University of Southampton, Southampton, UK
| | - Jonathan Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Ronney B Panerai
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM), Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, British Heart Foundation, Glenfield Hospital, Leicester, UK
| | - Georgios D Mitsis
- Department of Bioengineering, McGill University, Montreal, QC, Canada
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Chaleckas E, Putnynaite V, Lapinskiene I, Preiksaitis A, Serpytis M, Rocka S, Bartusis L, Petkus V, Ragauskas A. Impaired cerebral autoregulation detected in early prevasospasm period is associated with unfavorable outcome after spontaneous subarachnoid hemorrhage: an observational prospective pilot study. Ultrasound J 2024; 16:24. [PMID: 38619783 PMCID: PMC11018731 DOI: 10.1186/s13089-024-00371-8] [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: 12/11/2023] [Accepted: 03/11/2024] [Indexed: 04/16/2024] Open
Abstract
BACKGROUND Subarachnoid hemorrhage (SAH) patients with cerebral autoregulation (CA) impairment at an early post-SAH period are at high risk of unfavorable outcomes due to delayed cerebral ischemia (DCI) or other complications. Limited evidence exists for an association between early-stage CA impairments and SAH patient outcomes. The objective of this prospective study was to explore associations between CA impairments detected in early post-SAH snapshot examinations and patient outcomes. METHODS The pilot observational study included 29 SAH patients whose CA status was estimated 2-3 days after spontaneous aneurysm rupture and a control group of 15 healthy volunteers for comparison. Inflatable leg recovery boots (reboots.com, Germany) were used for the safe controlled generation of arterial blood pressure (ABP) changes necessary for reliable CA examination. At least 5 inflation‒deflation cycles of leg recovery boots with a 2-3 min period were used during examinations. CA status was assessed according to the delay time (∆TCBFV) measured between ABP(t) and cerebral blood flow velocity (CBFV(t)) signals during artificially induced ABP changes at boot deflation cycle. CBFV was measured in middle cerebral artery by using transcranial Doppler device. RESULTS Statistically significant differences in ∆TCBFV were found between SAH patients with unfavorable outcomes (∆TCBFV = 1.37 ± 1.23 s) and those with favorable outcomes (∆TCBFV = 2.86 ± 0.99 s) (p < 0.001). Early assessment of baroreflex sensitivity (BRS) during the deflation cycle showed statistically significant differences between the DCI and non-DCI patient groups (p = 0.039). CONCLUSIONS A relatively small delay of ∆TCBFV <1.6 s between CBFV(t) and ABP(t) waves could be an early warning sign associated with unfavorable outcomes in SAH patients. The BRS during boot deflation can be used as a biomarker for the prediction of DCI. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT06028906. Registered 31 August 2023 - Retrospectively registered, https://www. CLINICALTRIALS gov/study/NCT06028906 .
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Affiliation(s)
- Edvinas Chaleckas
- Health Telematics Science Institute, Kaunas University of Technology, K. Barsausko str. 59, Kaunas, LT-51423, Lithuania
| | - Vilma Putnynaite
- Health Telematics Science Institute, Kaunas University of Technology, K. Barsausko str. 59, Kaunas, LT-51423, Lithuania
| | - Indre Lapinskiene
- Clinic of Anesthesiology and Intensive Care, Faculty of Medicine, Vilnius University, Vilnius, Lithuania
- Vilnius University Hospital Santaros Klinikos, Vilnius, Lithuania
| | - Aidanas Preiksaitis
- Clinic of Neurology and Neurosurgery, Faculty of Medicine, Vilnius University, Vilnius, Lithuania
- Vilnius University Hospital Santaros Klinikos, Vilnius, Lithuania
| | - Mindaugas Serpytis
- Clinic of Anesthesiology and Intensive Care, Faculty of Medicine, Vilnius University, Vilnius, Lithuania
- Vilnius University Hospital Santaros Klinikos, Vilnius, Lithuania
| | - Saulius Rocka
- Clinic of Neurology and Neurosurgery, Faculty of Medicine, Vilnius University, Vilnius, Lithuania
- Vilnius University Hospital Santaros Klinikos, Vilnius, Lithuania
| | - Laimonas Bartusis
- Health Telematics Science Institute, Kaunas University of Technology, K. Barsausko str. 59, Kaunas, LT-51423, Lithuania
| | - Vytautas Petkus
- Health Telematics Science Institute, Kaunas University of Technology, K. Barsausko str. 59, Kaunas, LT-51423, Lithuania.
| | - Arminas Ragauskas
- Health Telematics Science Institute, Kaunas University of Technology, K. Barsausko str. 59, Kaunas, LT-51423, Lithuania
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Canova D, Roatta S, Saglietto A, Scarsoglio S, Gianotto NR, Piccotti A, De Ferrari GM, Ridolfi L, Anselmino M. A Quantitative Assessment of Cerebral Hemodynamic Perturbations Associated with Long R-R Intervals in Atrial Fibrillation: A Pilot-Case-Based Experience. MEDICINA (KAUNAS, LITHUANIA) 2024; 60:531. [PMID: 38674177 PMCID: PMC11052310 DOI: 10.3390/medicina60040531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 02/08/2024] [Accepted: 03/18/2024] [Indexed: 04/28/2024]
Abstract
Background and Objectives: Atrial fibrillation (AF) results in systemic hemodynamic perturbations which impact cerebral circulation, possibly contributing to the development of dementia. However, evidence documenting effects in cerebral perfusion is scarce. The aim of this study is to provide a quantitative characterization of the magnitude and time course of the cerebral hemodynamic response to the short hypotensive events associated with long R-R intervals, as detected by near-infrared spectroscopy (NIRS). Materials and Methods: Cerebral NIRS signals and arterial blood pressure were continuously recorded along with an electrocardiogram in twelve patients with AF undergoing elective electrical cardioversion (ECV). The top 0.5-2.5% longest R-R intervals during AF were identified in each patient and used as triggers to carry out the triggered averaging of hemodynamic signals. The average curves were then characterized in terms of the latency, magnitude, and duration of the observed effects, and the possible occurrence of an overshoot was also investigated. Results: The triggered averages revealed that long R-R intervals produced a significant drop in diastolic blood pressure (-13.7 ± 6.1 mmHg) associated with an immediate drop in cerebral blood volume (THI: -0.92 ± 0.46%, lasting 1.9 ± 0.8 s), followed by a longer-lasting decrease in cerebral oxygenation (TOI: -0.79 ± 0.37%, lasting 5.2 ± 0.9 s, p < 0.01). The recovery of the TOI was generally followed by an overshoot (+1.06 ± 0.12%). These effects were progressively attenuated in response to R-R intervals of a shorter duration. Conclusions: Long R-R intervals cause a detectable and consistent cerebral hemodynamic response which concerns both cerebral blood volume and oxygenation and outlasts the duration of the systemic perturbation. These effects are compatible with the activation of dynamic autoregulatory mechanisms in response to the hypotensive stimulus.
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Affiliation(s)
- Daniela Canova
- Department of Neuroscience, University of Torino, 10125 Torino, Italy; (D.C.); (S.R.)
| | - Silvestro Roatta
- Department of Neuroscience, University of Torino, 10125 Torino, Italy; (D.C.); (S.R.)
| | - Andrea Saglietto
- Division of Cardiology, Cardiovascular and Thoracic Department, “Città della Salute e della Scienza” Hospital, 10126 Torino, Italy;
| | - Stefania Scarsoglio
- Department of Water Engineering, Politecnico di Torino, 10129 Torino, Italy;
| | - Nefer Roberta Gianotto
- Department of Medical Sciences, University of Torino, 10124 Torino, Italy; (N.R.G.); (A.P.); (G.M.D.F.)
| | - Alessandro Piccotti
- Department of Medical Sciences, University of Torino, 10124 Torino, Italy; (N.R.G.); (A.P.); (G.M.D.F.)
| | - Gaetano Maria De Ferrari
- Department of Medical Sciences, University of Torino, 10124 Torino, Italy; (N.R.G.); (A.P.); (G.M.D.F.)
| | - Luca Ridolfi
- Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino DIATI, 10129 Torino, Italy;
| | - Matteo Anselmino
- Division of Cardiology, Cardiovascular and Thoracic Department, “Città della Salute e della Scienza” Hospital, 10126 Torino, Italy;
- Department of Medical Sciences, University of Torino, 10124 Torino, Italy; (N.R.G.); (A.P.); (G.M.D.F.)
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Chen Y, Ma Y, Qin J, Wei X, Yang Y, Yuan Y, Yan F, Huo X, Han L. Blood pressure variability predicts poor outcomes in acute stroke patients without thrombolysis: a systematic review and meta-analysis. J Neurol 2024; 271:1160-1169. [PMID: 38036920 DOI: 10.1007/s00415-023-12054-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 10/07/2023] [Accepted: 10/09/2023] [Indexed: 12/02/2023]
Abstract
BACKGROUND Stroke is a significant medical condition, and blood pressure stands out as the most prevalent treatable risk factor associated with it. Researches link blood pressure variability (BPV) with stroke; however, the specific relationship between with the outcomes of stroke patients remains unclear. As blood pressure variability and mean blood pressure are interrelated, it remains uncertain whether BPV adds additional information to understanding the outcome of acute stroke patients. OBJECTIVE To systematically review studies investigating the association between blood pressure variability and prognosis in acute stroke patients. METHODS Embase, PubMed, Web of Science, and the Cochrane Library were searched for English language full-text articles from the inception to 1 January 2023. Stroke patients aged ≥ 18 years were included in this analysis. Stroke types were not restricted. RESULTS This meta-analysis shows that higher systolic blood pressure variability is linked to a higher risk of poor outcome, including function disability, mortality, early neurological deterioration, and stroke recurrence, among acute stroke patients without thrombolysis. A higher diastolic blood pressure variability is linked with to a higher risk of mortality and functional disability. CONCLUSIONS This review reveals that blood pressure variability is a novel and clinically relevant risk factor for stroke patients' outcome. Future studies should investigate how best to measure and define BPV in acute stroke. Larger studies are warranted to provide more robust evidence in this area.
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Affiliation(s)
- Yajing Chen
- Evidence-Based Nursing Centre, School of Nursing, Lanzhou University, Lanzhou, Gansu Province, China
| | - Yuxia Ma
- Evidence-Based Nursing Centre, School of Nursing, Lanzhou University, Lanzhou, Gansu Province, China.
- The First Clinical Medical College of Lanzhou University, Lanzhou, 730030, Gansu Province, China.
| | - Jiangxia Qin
- Evidence-Based Nursing Centre, School of Nursing, Lanzhou University, Lanzhou, Gansu Province, China
| | - Xiaoqin Wei
- Evidence-Based Nursing Centre, School of Nursing, Lanzhou University, Lanzhou, Gansu Province, China
| | - Yiyi Yang
- Evidence-Based Nursing Centre, School of Nursing, Lanzhou University, Lanzhou, Gansu Province, China
| | - Yue Yuan
- Evidence-Based Nursing Centre, School of Nursing, Lanzhou University, Lanzhou, Gansu Province, China
| | - Fanghong Yan
- Evidence-Based Nursing Centre, School of Nursing, Lanzhou University, Lanzhou, Gansu Province, China
| | - Xiaoning Huo
- The Third People's Hospital of Lanzhou, No.130 Jianlan New Village, Lanzhou, Gansu Province, China
| | - Lin Han
- Evidence-Based Nursing Centre, School of Nursing, Lanzhou University, Lanzhou, Gansu Province, China.
- Department of Nursing, Gansu Provincial Hospital, No. 204 Donggang West Road, Lanzhou, Gansu Province, China.
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5
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Li W, Zhang Z, Li Z, Gui Z, Shang Y. Correlation and asynchronization of electroencephalogram and cerebral blood flow in active and passive stimulations. J Neural Eng 2023; 20:066007. [PMID: 37931297 DOI: 10.1088/1741-2552/ad0a02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 11/06/2023] [Indexed: 11/08/2023]
Abstract
Objective.Real-time brain monitoring is of importance for intraoperative surgeries and intensive care unit, in order to take timely clinical interventions. Electroencephalogram (EEG) is a conventional technique for recording neural excitations (e.g. brain waves) in the cerebral cortex, and near infrared diffuse correlation spectroscopy (DCS) is an emerging technique that can directly measure the cerebral blood flow (CBF) in microvasculature system. Currently, the relationship between the neural activities and cerebral hemodynamics that reflects the vasoconstriction features of cerebral vessels, especially under both active and passive situation, has not been elucidated thus far, which triggers the motivation of this study.Approach.We used the verbal fluency test as an active cognitive stimulus to the brain, and we manipulated blood pressure changes as a passive challenge to the brain. Under both protocols, the CBF and EEG responses were longitudinally monitored throughout the cerebral stimulus. Power spectrum approaches were applied the EEG signals and compared with CBF responses.Main results.The results show that the EEG response was significantly faster and larger in amplitude during the active cognitive task, when compared to the CBF, but with larger individual variability. By contrast, CBF is more sensitive when response to the passive task, and with better signal stability. We also found that there was a correlation (p< 0.01,r= 0.866,R2= 0.751) between CBF and EEG in initial response during the active task, but no significant correlation (p> 0.05) was found during the passive task. The similar relations were also found between regional brain waves and blood flow.Significance.The asynchronization and correlation between the two measurements indicates the necessity of monitoring both variables for comprehensive understanding of cerebral physiology. Deep exploration of their relationships provides promising implications for DCS/EEG integration in the diagnosis of various neurovascular and psychiatric diseases.
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Affiliation(s)
- Weilong Li
- State Key Laboratory of Dynamic Measurement Technology, North University of China, Taiyuan, People's Republic of China
| | - Zihao Zhang
- School of Electronics and Information Engineering, Harbin Institute of Technology, Harbin, People's Republic of China
| | - Zhiyi Li
- Electronic Information College, Northwestern Polytechnical University, Xian, People's Republic of China
| | - Zhiguo Gui
- State Key Laboratory of Dynamic Measurement Technology, North University of China, Taiyuan, People's Republic of China
| | - Yu Shang
- State Key Laboratory of Dynamic Measurement Technology, North University of China, Taiyuan, People's Republic of China
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Shoemaker LN, Milej D, Sajid A, Mistry J, Lawrence KS, Shoemaker JK. Characterization of cerebral macro- and microvascular hemodynamics during transient hypotension. J Appl Physiol (1985) 2023; 135:717-725. [PMID: 37560766 PMCID: PMC10642516 DOI: 10.1152/japplphysiol.00743.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 06/26/2023] [Accepted: 08/04/2023] [Indexed: 08/11/2023] Open
Abstract
The aim of the current study was to establish the interplay between blood flow patterns within a large cerebral artery and a downstream microvascular segment under conditions of transiently reduced mean arterial pressure (MAP). We report data from nine young, healthy participants (5 women; 26 ± 4 yr) acquired during a 15-s bout of sudden-onset lower body negative pressure (LBNP; -80 mmHg). Simultaneous changes in microvascular cerebral blood flow (CBF) and middle cerebral artery blood velocity (MCAvmean) were captured using diffuse correlation spectroscopy (DCS) and transcranial Doppler ultrasound (TCD), respectively. Brachial blood pressure (finger photoplethysmography) and TCD waveforms were extracted at baseline and during the nadir blood pressure (BP) response to LBNP and analyzed using a modified Windkessel model to calculate indices of cerebrovascular resistance (Ri) and compliance (Ci). Compared with baseline, rapid-onset LBNP decreased MAP by 22 ± 16% and Ri by 14 ± 10% (both P ≤ 0.03). Ci increased (322 ± 298%; P < 0.01) but MCAvmean (-8 ± 16%; P = 0.09) and CBF (-2 ± 3%; P = 0.29) were preserved. The results provide evidence that changes in both vascular resistance and compliance preserve CBF, as indexed by no significant changes in MCAvmean or DCS microvascular flow, during transient hypotension.NEW & NOTEWORTHY To characterize the relationship between cerebrovascular patterns within the large middle cerebral artery (MCA) and a downstream microvascular segment, we used a novel combination of transcranial Doppler ultrasound of the MCA and optical monitoring of a downstream microvascular segment, respectively, under conditions of transiently reduced mean arterial pressure (i.e., lower body negative pressure, -80 mmHg). A rapid increase in vessel compliance accompanied the maintenance of MCA blood velocity and downstream microvascular flow.
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Affiliation(s)
- Leena N Shoemaker
- Imaging Program, Lawson Health Research Institute, London, Ontario, Canada
- Department of Medical Biophysics, Western University, London, Ontario, Canada
- School of Kinesiology, Western University, London, Ontario, Canada
| | - Daniel Milej
- Imaging Program, Lawson Health Research Institute, London, Ontario, Canada
- Department of Medical Biophysics, Western University, London, Ontario, Canada
| | - Aleena Sajid
- School of Kinesiology, Western University, London, Ontario, Canada
| | - Jigneshkumar Mistry
- Imaging Program, Lawson Health Research Institute, London, Ontario, Canada
- Department of Medical Biophysics, Western University, London, Ontario, Canada
| | - Keith St Lawrence
- Imaging Program, Lawson Health Research Institute, London, Ontario, Canada
- Department of Medical Biophysics, Western University, London, Ontario, Canada
| | - J Kevin Shoemaker
- School of Kinesiology, Western University, London, Ontario, Canada
- Department of Physiology and Pharmacology, Western University, London, Ontario, Canada
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7
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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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Huang D, Guo Y, Guan X, Pan L, Zhu Z, Chen Z, Dijkhuizen RM, Duering M, Yu F, Boltze J, Li P. Recent advances in arterial spin labeling perfusion MRI in patients with vascular cognitive impairment. J Cereb Blood Flow Metab 2023; 43:173-184. [PMID: 36284489 PMCID: PMC9903225 DOI: 10.1177/0271678x221135353] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 08/01/2022] [Accepted: 09/21/2022] [Indexed: 01/24/2023]
Abstract
Cognitive impairment (CI) is a major health concern in aging populations. It impairs patients' independent life and may progress to dementia. Vascular cognitive impairment (VCI) encompasses all cerebrovascular pathologies that contribute to cognitive impairment (CI). Moreover, the majority of CI subtypes involve various aspects of vascular dysfunction. Recent research highlights the critical role of reduced cerebral blood flow (CBF) in the progress of VCI, and the detection of altered CBF may help to detect or even predict the onset of VCI. Arterial spin labeling (ASL) is a non-invasive, non-ionizing perfusion MRI technique for assessing CBF qualitatively and quantitatively. Recent methodological advances enabling improved signal-to-noise ratio (SNR) and data acquisition have led to an increase in the use of ASL to assess CBF in VCI patients. Combined with other imaging modalities and biomarkers, ASL has great potential for identifying early VCI and guiding prediction and prevention strategies. This review focuses on recent advances in ASL-based perfusion MRI for identifying patients at high risk of VCI.
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Affiliation(s)
- Dan Huang
- Department of Anesthesiology, Clinical Research Center, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yunlu Guo
- Department of Anesthesiology, Clinical Research Center, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiaoyu Guan
- Department of Anesthesiology, Clinical Research Center, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lijun Pan
- Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ziyu Zhu
- Department of Anesthesiology, Clinical Research Center, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zeng’ai Chen
- Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Rick M Dijkhuizen
- Biomedical MR Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, the Netherlands
| | - Marco Duering
- Institute for Stroke and Dementia Research, University Hospital, LMU Munich, Germany
- Medical Image Analysis Center (MIAC) and qbig, Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | - Fang Yu
- Department of Anesthesiology, Westchester Medical Center, New York Medical College, NY, USA
| | - Johannes Boltze
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Peiying Li
- Department of Anesthesiology, Clinical Research Center, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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9
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Favilla CG, Mullen MT, Kahn F, Rasheed IYD, Messe SR, Parthasarathy AB, Yodh AG. Dynamic cerebral autoregulation measured by diffuse correlation spectroscopy. J Cereb Blood Flow Metab 2023:271678X231153728. [PMID: 36703572 PMCID: PMC10369149 DOI: 10.1177/0271678x231153728] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Dynamic cerebral autoregulation (dCA) can be derived from spontaneous oscillations in arterial blood pressure (ABP) and cerebral blood flow (CBF). Transcranial Doppler (TCD) measures CBF-velocity and is commonly used to assess dCA. Diffuse correlation spectroscopy (DCS) is a promising optical technique for non-invasive CBF monitoring, so here we aimed to validate DCS as a tool for quantifying dCA. In 33 healthy adults and 17 acute ischemic stroke patients, resting-state hemodynamic were monitored simultaneously with high-speed (20 Hz) DCS and TCD. dCA parameters were calcaulated by a transfer function analysis using a Fourier decomposition of ABP and CBF (or CBF-velocity). Strong correlation was found between DCS and TCD measured gain (magnitude of regulation) in healthy volunteers (r = 0.73, p < 0.001) and stroke patients (r = 0.76, p = 0.003). DCS-gain retained strong test-retest reliability in both groups (ICC 0.87 and 0.82, respectively). DCS and TCD-derived phase (latency of regulation) did not significantly correlate in healthy volunteers (r = 0.12, p = 0.50) but moderately correlated in stroke patients (r = 0.65, p = 0.006). DCS-derived phase was reproducible in both groups (ICC 0.88 and 0.90, respectively). High-frequency DCS is a promising non-invasive bedside technique that can be leveraged to quantify dCA from resting-state data, but the discrepancy between TCD and DCS-derived phase requires further investigation.
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Affiliation(s)
| | - Michael T Mullen
- Department of Neurology, 6558Temple University, Philadelphia, USA
| | - Farhan Kahn
- Department of Neurology, 6572University of Pennsylvania, Philadelphia, USA
| | | | - Steven R Messe
- Department of Neurology, 6572University of Pennsylvania, Philadelphia, USA
| | | | - Arjun G Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, USA
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10
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Yang J, Acharya D, Scammon WB, Schmitt S, Crane EC, Smith MA, Kainerstorfer JM. Cerebrovascular Impedance as a Function of Cerebral Perfusion Pressure. IEEE OPEN JOURNAL OF ENGINEERING IN MEDICINE AND BIOLOGY 2023; 4:96-101. [PMID: 37234191 PMCID: PMC10208597 DOI: 10.1109/ojemb.2023.3236267] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/19/2022] [Accepted: 12/21/2022] [Indexed: 09/30/2023] Open
Abstract
Goal: Cerebrovascular impedance is modulated by a vasoactive autoregulative mechanism in response to changes in cerebral perfusion pressure. Characterization of impedance and the limits of autoregulation are important biomarkers of cerebral health. We developed a method to quantify impedance based on the spectral content of cerebral blood flow and volume at the cardiac frequency, measured with diffuse optical methods. Methods: In three non-human primates, we modulated cerebral perfusion pressure beyond the limits of autoregulation. Cerebral blood flow and volume were measured with diffuse correlation spectroscopy and near-infrared spectroscopy, respectively. Results: We show that impedance can be used to identify the lower and upper limits of autoregulation. Conclusions: This impedance method may be an alternative method to measure autoregulation and a way of assessing cerebral health non-invasively at the clinical bedside.
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Affiliation(s)
- Jason Yang
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
| | - Deepshikha Acharya
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
| | - William B. Scammon
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
| | - Samantha Schmitt
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
- Neuroscience InstituteCarnegie Mellon UniversityPittsburghPA15213USA
| | - Emily C. Crane
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
| | - Matthew A. Smith
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
- Neuroscience InstituteCarnegie Mellon UniversityPittsburghPA15213USA
| | - Jana M. Kainerstorfer
- Department of Biomedical EngineeringCarnegie Mellon UniversityPittsburghPA15213USA
- Neuroscience InstituteCarnegie Mellon UniversityPittsburghPA15213USA
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11
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Yang J, Ruesch A, Kainerstorfer JM. Cerebrovascular impedance estimation with near-infrared and diffuse correlation spectroscopy. NEUROPHOTONICS 2023; 10:015002. [PMID: 36699625 PMCID: PMC9868286 DOI: 10.1117/1.nph.10.1.015002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 12/29/2022] [Indexed: 06/17/2023]
Abstract
SIGNIFICANCE Cerebrovascular impedance (CVI) is related to cerebral autoregulation (CA), which is the mechanism of the brain to maintain near-constant cerebral blood flow (CBF) despite changes in cerebral perfusion pressure (CPP). Changes in blood vessel impedance enable the stabilization of blood flow. Due to the interplay between CVI and CA, assessment of CVI may enable quantification of CA and may serve as a biomarker for cerebral health. AIM We developed a method to quantify CVI based on a combination of diffuse correlation spectroscopy (DCS) and continuous wave (CW) near-infrared spectroscopy (NIRS). Data on healthy human volunteers were used to validate the method. APPROACH A combined high-speed DCS-NIRS system was developed, allowing for simultaneous, noninvasive blood flow, and volume measurements in the same tissue compartment. Blood volume was used as a surrogate measurement for blood pressure and CVI was calculated as the spectral ratio of blood volume and blood flow changes. This technique was validated on six healthy human volunteers undergoing postural changes to elicit CVI changes. RESULTS Averaged across the six subjects, a decrease in CVI was found for a head of bed (HOB) tilting of - 40 deg . These impedance changes were reversed when returning to the horizontal (0 deg) HOB baseline. CONCLUSIONS We developed a combined DCS-NIRS system, which measures CBF and volume changes, which we demonstrate can be used to measure CVI. Using CVI as a metric of CA may be beneficial for assessing cerebral health, especially in patients where CPP is altered.
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Affiliation(s)
- Jason Yang
- Carnegie Mellon University, Department of Biomedical Engineering, Pittsburgh, Pennsylvania, United States
| | - Alexander Ruesch
- Carnegie Mellon University, Department of Biomedical Engineering, Pittsburgh, Pennsylvania, United States
- Carnegie Mellon University, Neuroscience Institute, Pittsburgh, Pennsylvania, United States
| | - Jana M. Kainerstorfer
- Carnegie Mellon University, Department of Biomedical Engineering, Pittsburgh, Pennsylvania, United States
- Carnegie Mellon University, Neuroscience Institute, Pittsburgh, Pennsylvania, United States
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12
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Tagliabue S, Lindner C, da Prat IC, Sanchez-Guerrero A, Serra I, Kacprzak M, Maruccia F, Silva OM, Weigel UM, de Nadal M, Poca MA, Durduran T. Comparison of cerebral metabolic rate of oxygen, blood flow, and bispectral index under general anesthesia. NEUROPHOTONICS 2023; 10:015006. [PMID: 36911206 PMCID: PMC9993084 DOI: 10.1117/1.nph.10.1.015006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 02/07/2023] [Indexed: 06/18/2023]
Abstract
SIGNIFICANCE The optical measurement of cerebral oxygen metabolism was evaluated. AIM Compare optically derived cerebral signals to the electroencephalographic bispectral index (BIS) sensors to monitor propofol-induced anesthesia during surgery. APPROACH Relative cerebral metabolic rate of oxygen ( rCMRO 2 ) and blood flow (rCBF) were measured by time-resolved and diffuse correlation spectroscopies. Changes were tested against the relative BIS (rBIS) ones. The synchronism in the changes was also assessed by the R-Pearson correlation. RESULTS In 23 measurements, optically derived signals showed significant changes in agreement with rBIS: during propofol induction, rBIS decreased by 67% [interquartile ranges (IQR) 62% to 71%], rCMRO 2 by 33% (IQR 18% to 46%), and rCBF by 28% (IQR 10% to 37%). During recovery, a significant increase was observed for rBIS (48%, IQR 38% to 55%), rCMRO 2 (29%, IQR 17% to 39%), and rCBF (30%, IQR 10% to 44%). The significance and direction of the changes subject-by-subject were tested: the coupling between the rBIS, rCMRO 2 , and rCBF was witnessed in the majority of the cases (14/18 and 12/18 for rCBF and 19/21 and 13/18 for rCMRO 2 in the initial and final part, respectively). These changes were also correlated in time ( R > 0.69 to R = 1 , p - values < 0.05 ). CONCLUSIONS Optics can reliably monitor rCMRO 2 in such conditions.
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Affiliation(s)
- Susanna Tagliabue
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Claus Lindner
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | | | - Angela Sanchez-Guerrero
- Vall d’Hebron University Hospital Research Institute, Neurotraumatology and Neurosurgery Research Unit, Barcelona, Spain
| | - Isabel Serra
- Centre de Recerca Matemàtica, Bellaterra, Spain
- Barcelona Supercomputing Center—Centre Nacional de Supercomputació, Spain
| | - Michał Kacprzak
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
- Nalecz Institute of Biocybernetics and Biomedical Engineering PAS, Warsaw, Poland
| | - Federica Maruccia
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
- Vall d’Hebron University Hospital Research Institute, Neurotraumatology and Neurosurgery Research Unit, Barcelona, Spain
| | - Olga Martinez Silva
- Vall d’Hebron University Hospital, Department of Anesthesiology, Barcelona, Spain
| | - Udo M. Weigel
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
- HemoPhotonics S.L., Mediterranean Technology Park, Barcelona, Spain
| | - Miriam de Nadal
- Vall d’Hebron University Hospital, Department of Anesthesiology, Barcelona, Spain
- Universidad Autònoma de Barcelona, Plaça Cívica, Barcelona, Spain
| | - Maria A. Poca
- Vall d’Hebron University Hospital Research Institute, Neurotraumatology and Neurosurgery Research Unit, Barcelona, Spain
- Universidad Autònoma de Barcelona, Plaça Cívica, Barcelona, Spain
- Vall d’Hebron University Hospital, Department of Neurosurgery, Barcelona, Spain
| | - Turgut Durduran
- ICFO – Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
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13
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Biswas A, Parthasarathy AB. Lossless Compressed Sensing of Photon Counts for Fast Diffuse Correlation Spectroscopy. IEEE ACCESS : PRACTICAL INNOVATIONS, OPEN SOLUTIONS 2022; 10:129754-129762. [PMID: 36644002 PMCID: PMC9835098 DOI: 10.1109/access.2022.3228439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Diffuse Correlation Spectroscopy (DCS), a noninvasive optical technique, measures deep tissue blood flow using avalanche photon counting modules and data acquisition devices such as FPGAs or correlator boards. Conventional DCS instruments use in-processor counter modules that consume 32 bits/channel which is inefficient for low-photon budget situations prevalent in diffuse optics. Scaling these photon counters for large-scale imaging applications is difficult due to bandwidth and processing time considerations. Here, we introduce a new, lossless compressed sensing approach for fast and efficient detection of photon counts. The compressed DCS method uses an array of binary-coded-decimal counters to record photon counts from 8 channels simultaneously as a single 32-bit number. We validate the compressed DCS approach by comparisons with conventional DCS in experiments on tissue simulating phantoms and in-vivo arm cuff occlusion. Lossless compressed DCS was implemented with 87.5% compression efficiency. In tissue simulating phantoms, it was able to accurately estimate a tissue blood flow index, with no statistically significant difference compared to conventional DCS. Compressed DCS also recorded blood flow in vivo, in human forearm, with signal-to-noise ratio and dynamic range comparable to conventional DCS. Lossless 87.5% efficient compressed sensing counting of photon counts meets and exceeds benchmarks set by conventional DCS systems, offering a low-cost alternative for fast (~100 Hz) deep tissue blood flow measurement with optics.
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Affiliation(s)
- Arindam Biswas
- Department of Electrical Engineering, University of South Florida, Tampa, FL 33620, USA
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14
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Ayaz H, Baker WB, Blaney G, Boas DA, Bortfeld H, Brady K, Brake J, Brigadoi S, Buckley EM, Carp SA, Cooper RJ, Cowdrick KR, Culver JP, Dan I, Dehghani H, Devor A, Durduran T, Eggebrecht AT, Emberson LL, Fang Q, Fantini S, Franceschini MA, Fischer JB, Gervain J, Hirsch J, Hong KS, Horstmeyer R, Kainerstorfer JM, Ko TS, Licht DJ, Liebert A, Luke R, Lynch JM, Mesquida J, Mesquita RC, Naseer N, Novi SL, Orihuela-Espina F, O’Sullivan TD, Peterka DS, Pifferi A, Pollonini L, Sassaroli A, Sato JR, Scholkmann F, Spinelli L, Srinivasan VJ, St. Lawrence K, Tachtsidis I, Tong Y, Torricelli A, Urner T, Wabnitz H, Wolf M, Wolf U, Xu S, Yang C, Yodh AG, Yücel MA, Zhou W. Optical imaging and spectroscopy for the study of the human brain: status report. NEUROPHOTONICS 2022; 9:S24001. [PMID: 36052058 PMCID: PMC9424749 DOI: 10.1117/1.nph.9.s2.s24001] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
This report is the second part of a comprehensive two-part series aimed at reviewing an extensive and diverse toolkit of novel methods to explore brain health and function. While the first report focused on neurophotonic tools mostly applicable to animal studies, here, we highlight optical spectroscopy and imaging methods relevant to noninvasive human brain studies. We outline current state-of-the-art technologies and software advances, explore the most recent impact of these technologies on neuroscience and clinical applications, identify the areas where innovation is needed, and provide an outlook for the future directions.
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Affiliation(s)
- Hasan Ayaz
- Drexel University, School of Biomedical Engineering, Science, and Health Systems, Philadelphia, Pennsylvania, United States
- Drexel University, College of Arts and Sciences, Department of Psychological and Brain Sciences, Philadelphia, Pennsylvania, United States
| | - Wesley B. Baker
- Children’s Hospital of Philadelphia, Division of Neurology, Philadelphia, Pennsylvania, United States
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Giles Blaney
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
| | - David A. Boas
- Boston University Neurophotonics Center, Boston, Massachusetts, United States
- Boston University, College of Engineering, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Heather Bortfeld
- University of California, Merced, Departments of Psychological Sciences and Cognitive and Information Sciences, Merced, California, United States
| | - Kenneth Brady
- Lurie Children’s Hospital, Northwestern University Feinberg School of Medicine, Department of Anesthesiology, Chicago, Illinois, United States
| | - Joshua Brake
- Harvey Mudd College, Department of Engineering, Claremont, California, United States
| | - Sabrina Brigadoi
- University of Padua, Department of Developmental and Social Psychology, Padua, Italy
| | - Erin M. Buckley
- 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
| | - Stefan A. Carp
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, United States
| | - Robert J. Cooper
- University College London, Department of Medical Physics and Bioengineering, DOT-HUB, London, United Kingdom
| | - Kyle R. Cowdrick
- Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Joseph P. Culver
- Washington University School of Medicine, Department of Radiology, St. Louis, Missouri, United States
| | - Ippeita Dan
- Chuo University, Faculty of Science and Engineering, Tokyo, Japan
| | - Hamid Dehghani
- University of Birmingham, School of Computer Science, Birmingham, United Kingdom
| | - Anna Devor
- Boston University, College of Engineering, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Turgut Durduran
- ICFO – The Institute of Photonic Sciences, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
- Institució Catalana de Recerca I Estudis Avançats (ICREA), Barcelona, Spain
| | - Adam T. Eggebrecht
- Washington University in St. Louis, Mallinckrodt Institute of Radiology, St. Louis, Missouri, United States
| | - Lauren L. Emberson
- University of British Columbia, Department of Psychology, Vancouver, British Columbia, Canada
| | - Qianqian Fang
- Northeastern University, Department of Bioengineering, Boston, Massachusetts, United States
| | - Sergio Fantini
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
| | - Maria Angela Franceschini
- Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Massachusetts, United States
| | - Jonas B. Fischer
- ICFO – The Institute of Photonic Sciences, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
| | - Judit Gervain
- University of Padua, Department of Developmental and Social Psychology, Padua, Italy
- Université Paris Cité, CNRS, Integrative Neuroscience and Cognition Center, Paris, France
| | - Joy Hirsch
- Yale School of Medicine, Department of Psychiatry, Neuroscience, and Comparative Medicine, New Haven, Connecticut, United States
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Keum-Shik Hong
- Pusan National University, School of Mechanical Engineering, Busan, Republic of Korea
- Qingdao University, School of Automation, Institute for Future, Qingdao, China
| | - Roarke Horstmeyer
- Duke University, Department of Biomedical Engineering, Durham, North Carolina, United States
- Duke University, Department of Electrical and Computer Engineering, Durham, North Carolina, United States
- Duke University, Department of Physics, Durham, North Carolina, United States
| | - Jana M. Kainerstorfer
- Carnegie Mellon University, Department of Biomedical Engineering, Pittsburgh, Pennsylvania, United States
- Carnegie Mellon University, Neuroscience Institute, Pittsburgh, Pennsylvania, United States
| | - Tiffany S. Ko
- Children’s Hospital of Philadelphia, Division of Cardiothoracic Anesthesiology, Philadelphia, Pennsylvania, United States
| | - Daniel J. Licht
- Children’s Hospital of Philadelphia, Division of Neurology, Philadelphia, Pennsylvania, United States
| | - Adam Liebert
- Polish Academy of Sciences, Nalecz Institute of Biocybernetics and Biomedical Engineering, Warsaw, Poland
| | - Robert Luke
- Macquarie University, Department of Linguistics, Sydney, New South Wales, Australia
- Macquarie University Hearing, Australia Hearing Hub, Sydney, New South Wales, Australia
| | - Jennifer M. Lynch
- Children’s Hospital of Philadelphia, Division of Cardiothoracic Anesthesiology, Philadelphia, Pennsylvania, United States
| | - Jaume Mesquida
- Parc Taulí Hospital Universitari, Critical Care Department, Sabadell, Spain
| | - Rickson C. Mesquita
- University of Campinas, Institute of Physics, Campinas, São Paulo, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology, Campinas, São Paulo, Brazil
| | - Noman Naseer
- Air University, Department of Mechatronics and Biomedical Engineering, Islamabad, Pakistan
| | - Sergio L. Novi
- University of Campinas, Institute of Physics, Campinas, São Paulo, Brazil
- Western University, Department of Physiology and Pharmacology, London, Ontario, Canada
| | | | - Thomas D. O’Sullivan
- University of Notre Dame, Department of Electrical Engineering, Notre Dame, Indiana, United States
| | - Darcy S. Peterka
- Columbia University, Zuckerman Mind Brain Behaviour Institute, New York, United States
| | | | - Luca Pollonini
- University of Houston, Department of Engineering Technology, Houston, Texas, United States
| | - Angelo Sassaroli
- Tufts University, Department of Biomedical Engineering, Medford, Massachusetts, United States
| | - João Ricardo Sato
- Federal University of ABC, Center of Mathematics, Computing and Cognition, São Bernardo do Campo, São Paulo, Brazil
| | - Felix Scholkmann
- University of Bern, Institute of Complementary and Integrative Medicine, Bern, Switzerland
- University of Zurich, University Hospital Zurich, Department of Neonatology, Biomedical Optics Research Laboratory, Zürich, Switzerland
| | - Lorenzo Spinelli
- National Research Council (CNR), IFN – Institute for Photonics and Nanotechnologies, Milan, Italy
| | - Vivek J. Srinivasan
- University of California Davis, Department of Biomedical Engineering, Davis, California, United States
- NYU Langone Health, Department of Ophthalmology, New York, New York, United States
- NYU Langone Health, Department of Radiology, New York, New York, United States
| | - Keith St. Lawrence
- Lawson Health Research Institute, Imaging Program, London, Ontario, Canada
- Western University, Department of Medical Biophysics, London, Ontario, Canada
| | - Ilias Tachtsidis
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Yunjie Tong
- Purdue University, Weldon School of Biomedical Engineering, West Lafayette, Indiana, United States
| | - Alessandro Torricelli
- Politecnico di Milano, Dipartimento di Fisica, Milan, Italy
- National Research Council (CNR), IFN – Institute for Photonics and Nanotechnologies, Milan, Italy
| | - Tara Urner
- Georgia Institute of Technology, Wallace H. Coulter Department of Biomedical Engineering, Atlanta, Georgia, United States
| | - Heidrun Wabnitz
- Physikalisch-Technische Bundesanstalt (PTB), Berlin, Germany
| | - Martin Wolf
- University of Zurich, University Hospital Zurich, Department of Neonatology, Biomedical Optics Research Laboratory, Zürich, Switzerland
| | - Ursula Wolf
- University of Bern, Institute of Complementary and Integrative Medicine, Bern, Switzerland
| | - Shiqi Xu
- Duke University, Department of Biomedical Engineering, Durham, North Carolina, United States
| | - Changhuei Yang
- California Institute of Technology, Department of Electrical Engineering, Pasadena, California, United States
| | - Arjun G. Yodh
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
| | - Meryem A. Yücel
- Boston University Neurophotonics Center, Boston, Massachusetts, United States
- Boston University, College of Engineering, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Wenjun Zhou
- University of California Davis, Department of Biomedical Engineering, Davis, California, United States
- China Jiliang University, College of Optical and Electronic Technology, Hangzhou, Zhejiang, China
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15
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Seong M, Oh Y, Lee K, Kim JG. Blood flow estimation via numerical integration of temporal autocorrelation function in diffuse correlation spectroscopy. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2022; 222:106933. [PMID: 35728393 DOI: 10.1016/j.cmpb.2022.106933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 05/27/2022] [Accepted: 06/02/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND AND OBJECTIVE Diffuse correlation spectroscopy (DCS) is an optical technique widely used to monitor blood flow. Recently, efforts have been made to derive new signal processing methods to minimize the systems used and shorten the signal processing time. Herein, we propose alternative approaches to obtain blood flow information via DCS by numerically integrating the temporal autocorrelation curves. METHODS We use the following methods: the inverse of K2 (IK2)-based on the framework of diffuse speckle contrast analysis-and the inverse of the numerical integration of squared g1 (INISg1) which, based on the normalized electric field autocorrelation curve, is more simplified than IK2. In addition, g1 thresholding is introduced to further reduce computational time and make the suggested methods comparable to the conventional nonlinear fitting approach. To validate the feasibility of the suggested methods, studies using simulation, liquid phantom, and in vivo settings were performed. In the meantime, the suggested methods were implemented and tested on three types of Arduino (Arduino Due, Arduino Nano 33 BLE Sense, and Portenta H7) to demonstrate the possibility of miniaturizing the DCS systems using microcotrollers for signal processing. RESULTS The simulation and experimental results confirm that both IK2 and INISg1 are sufficiently relevant to capture the changes in blood flow information. More interestingly, when g1 thresholding was applied, our results showed that INISg1 outperformed IK2. It was further confirmed that INISg1 with g1 thresholding implemented on a PC and Portenta H7, an advanced Arduino board, performed faster than did the deep learning-based, state-of-the-art processing method. CONCLUSION Our findings strongly indicate that INISg1 with g1 thresholding could be an alternative approach to derive relative blood flow information via DCS, which may contribute to the simplification of DCS methodologies.
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Affiliation(s)
- Myeongsu Seong
- School of Information Science and Technology, Nantong University, Nantong, Jiangsu, China; Research Center for Intelligent Information Technology, Nantong University, Nantong, Jiangsu, China; Nantong Research Institute for Advanced Communication Technologies, Nantong, Jiangsu, China
| | - Yoonho Oh
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea
| | - Kijoon Lee
- Department of Electrical Engineering and Computer Science, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea.
| | - Jae G Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea.
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16
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Moore CH, Lin W. FPGA Correlator for Applications in Embedded Smart Devices. BIOSENSORS 2022; 12:bios12040236. [PMID: 35448296 PMCID: PMC9024689 DOI: 10.3390/bios12040236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 04/08/2022] [Accepted: 04/09/2022] [Indexed: 05/22/2023]
Abstract
Correlation has a variety of applications that require signal processing. However, it is computationally intensive, and software correlators require high-performance processors for real-time data analysis. This is a challenge for embedded devices because of the limitation of computing resources. Hardware correlators that use Field Programmable Gate Array (FPGA) technology can significantly boost computational power and bridge the gap between the need for high-performance computing and the limited processing power available in embedded devices. This paper presents a detailed FPGA-based correlator design at the register level along with the open-source Very High-Speed Integrated Circuit Hardware Description Language (VHDL) code. It includes base modules for linear and multi-tau correlators of varying sizes. Every module implements a simple and unified data interface for easy integration with standard and publicly available FPGA modules. Eighty-lag linear and multi-tau correlators were built for validation of the design. Three input data sets-constant signal, pulse signal, and sine signal-were used to test the accuracy of the correlators. The results from the FPGA correlators were compared against the outputs of equivalent software correlators and validated with the corresponding theoretical values. The FPGA correlators returned results identical to those from the software references for all tested data sets and were proven to be equivalent to their software counterparts. Their computation speed is at least 85,000 times faster than the software correlators running on a Xilinx MicroBlaze processor. The FPGA correlator can be easily implemented, especially on System on a Chip (SoC) integrated circuits that have processor cores and FPGA fabric. It is the ideal component for device-on-chip solutions in biosensing.
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17
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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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Effects of circulatory arrest and cardiopulmonary bypass on cerebral autoregulation in neonatal swine. Pediatr Res 2022; 91:1374-1382. [PMID: 33947997 PMCID: PMC8566324 DOI: 10.1038/s41390-021-01525-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 02/02/2021] [Accepted: 03/18/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND Cerebral autoregulation mechanisms help maintain adequate cerebral blood flow (CBF) despite changes in cerebral perfusion pressure. Impairment of cerebral autoregulation, during and after cardiopulmonary bypass (CPB), may increase risk of neurologic injury in neonates undergoing surgery. In this study, alterations of cerebral autoregulation were assessed in a neonatal swine model probing four perfusion strategies. METHODS Neonatal swine (n = 25) were randomized to continuous deep hypothermic cardiopulmonary bypass (DH-CPB, n = 7), deep hypothermic circulatory arrest (DHCA, n = 7), selective cerebral perfusion (SCP, n = 7) at deep hypothermia, or normothermic cardiopulmonary bypass (control, n = 4). The correlation coefficient (LDx) between laser Doppler measurements of CBF and mean arterial blood pressure was computed at initiation and conclusion of CPB. Alterations in cerebral autoregulation were assessed by the change between initial and final LDx measurements. RESULTS Cerebral autoregulation became more impaired (LDx increased) in piglets that underwent DH-CPB (initial LDx: median 0.15, IQR [0.03, 0.26]; final: 0.45, [0.27, 0.74]; p = 0.02). LDx was not altered in those undergoing DHCA (p > 0.99) or SCP (p = 0.13). These differences were not explained by other risk factors. CONCLUSIONS In a validated swine model of cardiac surgery, DH-CPB had a significant effect on cerebral autoregulation, whereas DHCA and SCP did not. IMPACT Approximately half of the patients who survive neonatal heart surgery with cardiopulmonary bypass (CPB) experience neurodevelopmental delays. This preclinical investigation takes steps to elucidate and isolate potential perioperative risk factors of neurologic injury, such as impairment of cerebral autoregulation, associated with cardiac surgical procedures involving CPB. We demonstrate a method to characterize cerebral autoregulation during CPB pump flow changes in a neonatal swine model of cardiac surgery. Cerebral autoregulation was not altered in piglets that underwent deep hypothermic circulatory arrest (DHCA) or selective cerebral perfusion (SCP), but it was altered in piglets that underwent deep hypothermic CBP.
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Robinson MB, Renna M, Ozana NN, Peruch A, Sakadzic S, Blackwell ML, Richardson JM, Aull BF, Carp SA, Franceschini MA. Diffuse correlation spectroscopy beyond the water peak enabled by cross-correlation of the signals from InGaAs/InP single photon detectors. IEEE Trans Biomed Eng 2021; 69:1943-1953. [PMID: 34847015 DOI: 10.1109/tbme.2021.3131353] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Diffuse correlation spectroscopy (DCS) is an optical technique that allows for the non-invasive measurement of blood flow. Recent work has shown that utilizing longer wavelengths beyond the traditional NIR range provides a significant improvement to signal-to-noise ratio (SNR). However, current detectors both sensitive to longer wavelengths and suitable for clinical applications (InGaAs/InP SPADs) suffer from suboptimal afterpulsing and dark noise characteristics. To overcome these barriers, we introduce a cross correlation method to more accurately recover blood flow information using InGaAs/InP SPADs. METHODS Two InGaAs/InP SPAD detectors were used for during in vitro and in vivo DCS measurements. Cross correlation of the photon streams from each detector was performed to calculate the correlation function. Detector operating parameters were varied to determine parameters which maximized measurement SNR. State-space modeling was performed to determine the detector characteristics at each operating point. RESULTS Evaluation of detector characteristics was performed across the range of operating conditions. Modeling the effects of the detector noise on the correlation function provided a method to correct the distortion of the correlation curve, yielding accurate recovery of flow information as confirmed by a reference detector. CONCLUSION Through a combination of cross-correlation of the signals from two detectors, model-based characterization of detector response, and optimization of detector operating parameters, the method allows for the accurate estimation of the true blood flow index. SIGNIFICANCE This work presents a method by which DCS can be performed at longer NIR wavelengths with existing detector technology, taking advantage of the increased SNR.
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20
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Pham T, Fernandez C, Blaney G, Tgavalekos K, Sassaroli A, Cai X, Bibu S, Kornbluth J, Fantini S. Noninvasive Optical Measurements of Dynamic Cerebral Autoregulation by Inducing Oscillatory Cerebral Hemodynamics. Front Neurol 2021; 12:745987. [PMID: 34867729 PMCID: PMC8637213 DOI: 10.3389/fneur.2021.745987] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 10/13/2021] [Indexed: 11/13/2022] Open
Abstract
Objective: Cerebral autoregulation limits the variability of cerebral blood flow (CBF) in the presence of systemic arterial blood pressure (ABP) changes. Monitoring cerebral autoregulation is important in the Neurocritical Care Unit (NCCU) to assess cerebral health. Here, our goal is to identify optimal frequency-domain near-infrared spectroscopy (FD-NIRS) parameters and apply a hemodynamic model of coherent hemodynamics spectroscopy (CHS) to assess cerebral autoregulation in healthy adult subjects and NCCU patients. Methods: In five healthy subjects and three NCCU patients, ABP oscillations at a frequency around 0.065 Hz were induced by cyclic inflation-deflation of pneumatic thigh cuffs. Transfer function analysis based on wavelet transform was performed to measure dynamic relationships between ABP and oscillations in oxy- (O), deoxy- (D), and total- (T) hemoglobin concentrations measured with different FD-NIRS methods. In healthy subjects, we also obtained the dynamic CBF-ABP relationship by using FD-NIRS measurements and the CHS model. In healthy subjects, an interval of hypercapnia was performed to induce cerebral autoregulation impairment. In NCCU patients, the optical measurements of autoregulation were linked to individual clinical diagnoses. Results: In healthy subjects, hypercapnia leads to a more negative phase difference of both O and D oscillations vs. ABP oscillations, which are consistent across different FD-NIRS methods and are highly correlated with a more negative phase difference CBF vs. ABP. In the NCCU, a less negative phase difference of D vs. ABP was observed in one patient as compared to two others, indicating a better autoregulation in that patient. Conclusions: Non-invasive optical measurements of induced phase difference between D and ABP show the strongest sensitivity to cerebral autoregulation. The results from healthy subjects also show that the CHS model, in combination with FD-NIRS, can be applied to measure the CBF-ABP dynamics for a better direct measurement of cerebral autoregulation.
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Affiliation(s)
- Thao Pham
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Cristianne Fernandez
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Giles Blaney
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Kristen Tgavalekos
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Angelo Sassaroli
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
| | - Xuemei Cai
- Department of Neurology, Tufts University School of Medicine, Boston, MA, United States
| | - Steve Bibu
- Department of Neurology, Tufts University School of Medicine, Boston, MA, United States
| | - Joshua Kornbluth
- Department of Neurology, Tufts University School of Medicine, Boston, MA, United States
| | - Sergio Fantini
- Department of Biomedical Engineering, Tufts University, Medford, MA, United States
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21
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Bryant JED, Birch AA, Panerai RB, Nikolic D, Bulters D, Simpson DM. Estimating confidence intervals for cerebral autoregulation: a parametric bootstrap approach. Physiol Meas 2021; 42. [PMID: 34534969 DOI: 10.1088/1361-6579/ac27b8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 09/17/2021] [Indexed: 11/12/2022]
Abstract
Cerebral autoregulation (CA) refers to the ability of the brain vasculature to control blood flow in the face of changing blood pressure. One of the methods commonly used to assess cerebral autoregulation, especially in participants at rest, is the analysis of phase derived from transfer function analysis (TFA), relating arterial blood pressure (ABP) to cerebral blood flow (CBF). This and other indexes of CA can provide consistent results when comparing groups of subjects (e.g. patients and healthy controls or normocapnia and hypercapnia) but can be quite variable within and between individuals. The objective of this paper is to present a novel parametric bootstrap method, used to estimate the sampling distribution and hence confidence intervals (CIs) of the mean phase estimate in the low-frequency band, in order to optimise estimation of measures of CA function and allow more robust inferences on the status of CA from individual recordings. A set of simulations was used to verify the proposed method under controlled conditions. In 20 healthy adult volunteers (age 25.53.5 years), ABP and CBF velocity (CBFV) were measured at rest, using a Finometer device and Transcranial Doppler (applied to the middle cerebral artery), respectively. For each volunteer, five individual recordings were taken on different days, each approximately 18 min long. Phase was estimated using TFA. Analysis of recorded data showed widely changing CIs over the duration of recordings, which could be reduced when noisy data and frequencies with low coherence were excluded from the analysis (Wilcoxon signed rank testp= 0.0065). The TFA window-lengths of 50s gave smaller CIs than lengths of 100s (p< 0.001) or 20s (p< 0.001), challenging the usual recommendation of 100s. The method adds a much needed flexible statistical tool for CA analysis in individual recordings.
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Affiliation(s)
- Jack E D Bryant
- Faculty of Engineering, University of Southampton, Highfield, Southampton, United Kingdom
| | - Anthony A Birch
- Department of Medical Physics, University Hospital Southampton NHS Foundation Trust, Southampton, Hampshire, United Kingdom
| | - Ronney B Panerai
- Department of Cardiovascular Sciences, University of Leicester, United Kingdom
| | - Dragana Nikolic
- Faculty of Engineering, University of Southampton, Highfield, Southampton, United Kingdom
| | - Diederik Bulters
- Wessex Neurological Centre, University Hospital Southampton NHS Foundation Trust, Southampton, Hampshire, United Kingdom
| | - David M Simpson
- Faculty of Engineering, University of Southampton, Highfield, Southampton, United Kingdom
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22
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Zhou W, Kholiqov O, Zhu J, Zhao M, Zimmermann LL, Martin RM, Lyeth BG, Srinivasan VJ. Functional interferometric diffusing wave spectroscopy of the human brain. SCIENCE ADVANCES 2021; 7:eabe0150. [PMID: 33980479 PMCID: PMC8115931 DOI: 10.1126/sciadv.abe0150] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Accepted: 03/23/2021] [Indexed: 05/18/2023]
Abstract
Cerebral blood flow (CBF) is essential for brain function, and CBF-related signals can inform us about brain activity. Yet currently, high-end medical instrumentation is needed to perform a CBF measurement in adult humans. Here, we describe functional interferometric diffusing wave spectroscopy (fiDWS), which introduces and collects near-infrared light via the scalp, using inexpensive detector arrays to rapidly monitor coherent light fluctuations that encode brain blood flow index (BFI), a surrogate for CBF. Compared to other functional optical approaches, fiDWS measures BFI faster and deeper while also providing continuous wave absorption signals. Achieving clear pulsatile BFI waveforms at source-collector separations of 3.5 cm, we confirm that optical BFI, not absorption, shows a graded hypercapnic response consistent with human cerebrovascular physiology, and that BFI has a better contrast-to-noise ratio than absorption during brain activation. By providing high-throughput measurements of optical BFI at low cost, fiDWS will expand access to CBF.
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Affiliation(s)
- Wenjun Zhou
- Department of Biomedical Engineering, University of California, Davis, Davis, CA, USA
| | - Oybek Kholiqov
- Department of Biomedical Engineering, University of California, Davis, Davis, CA, USA
| | - Jun Zhu
- Department of Biomedical Engineering, University of California, Davis, Davis, CA, USA
| | - Mingjun Zhao
- Department of Biomedical Engineering, University of California, Davis, Davis, CA, USA
| | - Lara L Zimmermann
- Department of Neurological Surgery, University of California, Davis, Sacramento, CA, USA
| | - Ryan M Martin
- Department of Neurological Surgery, University of California, Davis, Sacramento, CA, USA
| | - Bruce G Lyeth
- Department of Neurological Surgery, University of California, Davis, Sacramento, CA, USA
| | - Vivek J Srinivasan
- Department of Biomedical Engineering, University of California, Davis, Davis, CA, USA.
- Department of Ophthalmology and Vision Science, University of California, Davis, Sacramento, CA, USA
- Department of Ophthalmology, NYU Langone Health, New York, NY, USA
- Department of Radiology, NYU Langone Health, New York, NY, USA
- Tech4Health Institute, NYU Langone Health, New York, NY, USA
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Cerebrovascular pressure reactivity and intracranial pressure are associated with neurologic outcome after hypoxic-ischemic brain injury. Resuscitation 2021; 164:114-121. [PMID: 33930501 DOI: 10.1016/j.resuscitation.2021.04.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 04/09/2021] [Accepted: 04/20/2021] [Indexed: 11/21/2022]
Abstract
AIM We evaluated the association of physiological parameters measured by intracranial multimodality neuromonitoring with neurologic outcome in a consecutive series of patients with hypoxic-ischemic brain injury (HIBI). METHODS We retrospectively identified all patients with HIBI who underwent combined invasive intracranial pressure (ICP) and brain tissue oxygen (PbtO2) monitoring over a 3 year period. Cerebrovascular pressure reactivity index (PRx) was calculated continuously as a surrogate of cerebral autoregulation. Favorable outcome was defined as recovery of consciousness (Glasgow Coma Scale motor score = 6). Differences in mean ICP, PRx and PbtO2 for the entire monitoring period across outcomes were measured. Logistic regression and area under receiver operating characteristic (AUROC) curve were used to assess the association of each monitoring parameter with neurologic outcome. RESULTS We analyzed data from 36 patients. Most (89%) had an antecedent sudden cardiac arrest. Favorable outcome occurred in 8 (22%) patients. ICP and PRx were higher in patients with unfavorable outcome (ICP: 26 ± 4.1 mmHg vs 7.5 ± 2 mmHg, p = 0.0002; PRx: 0.51 ± 0.05 vs 0.11 ± 0.05, p < 0.0001). There was no significant difference in PbtO2 between groups (unfavorable: 20 ± 2.4 mmHg vs favorable: 25 ± 1.5 mmHg, p = 0.12). Both ICP (AUROC 0.84, 95%CI 0.72-0.98, p = 0.003) and PRx (AUROC 0.94, 95%CI 0.85-1, p = 0.0002) discriminated between favorable and unfavorable outcome, in contrast to PbtO2, (AUROC 0.59, 95%CI 0.39-0.78, p = 0.52). ICP > 15 mmHg, PRx > 0.2, and PbtO2 < 18 mmHg had sensitivity/specificity of 68%/100%, 89%/88%, and 40%/100% respectively for discriminating outcomes. CONCLUSION Cerebrovascular pressure reactivity and intracranial pressure appear to be associated with neurologic outcome in patients with HIBI.
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Dar IA, Khan IR, Maddox RK, Selioutski O, Donohue KL, Marinescu MA, Prasad SM, Quazi NH, Donlon JS, Loose EA, Ramirez GA, Ren J, Majeski JB, Abramson K, Durduran T, Busch DR, Choe R. Towards detection of brain injury using multimodal non-invasive neuromonitoring in adults undergoing extracorporeal membrane oxygenation. BIOMEDICAL OPTICS EXPRESS 2020; 11:6551-6569. [PMID: 33282508 PMCID: PMC7687959 DOI: 10.1364/boe.401641] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 09/16/2020] [Accepted: 10/02/2020] [Indexed: 05/27/2023]
Abstract
Extracorporeal membrane oxygenation (ECMO) is a form of cardiopulmonary bypass that provides life-saving support to critically ill patients whose illness is progressing despite maximal conventional support. Use in adults is expanding, however neurological injuries are common. Currently, the existing brain imaging tools are a snapshot in time and require high-risk patient transport. Here we assess the feasibility of measuring diffuse correlation spectroscopy, transcranial Doppler ultrasound, electroencephalography, and auditory brainstem responses at the bedside, and developing a cerebral autoregulation metric. We report preliminary results from two patients, demonstrating feasibility and laying the foundation for future studies monitoring neurological health during ECMO.
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Affiliation(s)
- Irfaan A. Dar
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14620, USA
| | - Imad R. Khan
- Department of Neurology, Division of Neurocritical Care, University of Rochester Medical Center, Rochester, New York 14642, USA
| | - Ross K. Maddox
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14620, USA
- Department of Neuroscience, University of Rochester, Rochester, New York 14620, USA
| | - Olga Selioutski
- Department of Neurology, Division of Epilepsy, University of Rochester Medical Center, Rochester, New York 14642, USA
| | - Kelly L. Donohue
- Department of Neurology, Division of Neurocritical Care, University of Rochester Medical Center, Rochester, New York 14642, USA
| | - Mark A. Marinescu
- Department of Medicine, Division of Cardiology, University of Rochester Medical Center, Rochester, New York 14642, USA
| | - Sunil M. Prasad
- Department of Surgery, Division of Cardiac Surgery, University of Rochester Medical Center, Rochester, New York 14642, USA
| | - Nadim H. Quazi
- Department of Biology, University of Rochester, Rochester, New York 14620, USA
| | - Jack S. Donlon
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14620, USA
| | - Emily A. Loose
- Department of Biology, University of Rochester, Rochester, New York 14620, USA
| | - Gabriel A. Ramirez
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14620, USA
| | - Jingxuan Ren
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14620, USA
| | - Joseph B. Majeski
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14620, USA
| | - Kenneth Abramson
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Turgut Durduran
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels (Barcelona), 08860, Spain
- Instituciò Catalana de Recerca i Estudis Avançats (ICREA), Castelldefels (Barcelona), 08015, Spain
| | - David R. Busch
- Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Regine Choe
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14620, USA
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York 14620, USA
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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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26
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Robinson M, Boas D, Sakadžic S, Franceschini MA, Carp S. Interferometric diffuse correlation spectroscopy improves measurements at long source-detector separation and low photon count rate. JOURNAL OF BIOMEDICAL OPTICS 2020; 25:JBO-200232R. [PMID: 33000571 PMCID: PMC7525153 DOI: 10.1117/1.jbo.25.9.097004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 09/11/2020] [Indexed: 05/04/2023]
Abstract
SIGNIFICANCE The use of diffuse correlation spectroscopy (DCS) has shown efficacy in research studies as a technique capable of noninvasively monitoring blood flow in tissue with applications in neuromonitoring, exercise science, and breast cancer management. The ability of DCS to resolve blood flow in these tissues is related to the optical sensitivity and signal-to-noise ratio (SNR) of the measurements, which in some cases, particularly adult cerebral blood flow measurements, is inadequate in a significant portion of the population. Improvements to DCS sensitivity and SNR could allow for greater clinical translation of this technique. AIM Interferometric diffuse correlation spectroscopy (iDCS) was characterized and compared to traditional homodyne DCS to determine possible benefits of utilizing heterodyne detection. APPROACH An iDCS system was constructed by modifying a homodyne DCS system with fused fiber couplers to create a Mach-Zehnder interferometer. Comparisons between homodyne and heterodyne detection were performed using an intralipid phantom characterized at two extended source-detector separations (2.4, 3.6 cm), different photon count rates, and a range of reference arm power levels. Characterization of the iDCS signal mixing was compared to theory. Precision of the estimation of the diffusion coefficient and SNR of the autocorrelation curve were compared between different measurement conditions that mimicked what would be seen in vivo. RESULTS The mixture of signals present in the heterodyne autocorrelation function was found to agree with the derived theory and resulted in accurate measurement of the diffusion coefficient of the phantom. Improvement of the SNR of the autocorrelation curve up to ∼2 × and up to 80% reduction in the variability of the diffusion coefficient fit were observed for all measurement cases as a function of increased reference arm power. CONCLUSIONS iDCS has the potential to improve characterization of blood flow in tissue at extended source-detector separations, enhancing depth sensitivity and SNR.
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Affiliation(s)
- Mitchell Robinson
- Athinoula A. Martinos Ctr. for Biomedical Imaging, Massachusetts General Hospital, United States
- Harvard-MIT Health Sciences and Technology, United States
- Harvard Medical School, United States
| | - David Boas
- Neurophotonics Ctr., Boston Univ., United States
| | - Sava Sakadžic
- Athinoula A. Martinos Ctr. for Biomedical Imaging, Massachusetts General Hospital, United States
- Harvard Medical School, United States
| | - Maria Angela Franceschini
- Athinoula A. Martinos Ctr. for Biomedical Imaging, Massachusetts General Hospital, United States
- Harvard Medical School, United States
| | - Stefan Carp
- Athinoula A. Martinos Ctr. for Biomedical Imaging, Massachusetts General Hospital, United States
- Harvard Medical School, United States
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27
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Crouzet C, Wilson RH, Lee D, Bazrafkan A, Tromberg BJ, Akbari Y, Choi B. Dissociation of Cerebral Blood Flow and Femoral Artery Blood Pressure Pulsatility After Cardiac Arrest and Resuscitation in a Rodent Model: Implications for Neurological Recovery. J Am Heart Assoc 2020; 9:e012691. [PMID: 31902319 PMCID: PMC6988151 DOI: 10.1161/jaha.119.012691] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Background Impaired neurological function affects 85% to 90% of cardiac arrest (CA) survivors. Pulsatile blood flow may play an important role in neurological recovery after CA. Cerebral blood flow (CBF) pulsatility immediately, during, and after CA and resuscitation has not been investigated. We characterized the effects of asphyxial CA on short‐term (<2 hours after CA) CBF and femoral arterial blood pressure (ABP) pulsatility and studied their relationship to cerebrovascular resistance (CVR) and short‐term neuroelectrical recovery. Methods and Results Male rats underwent asphyxial CA followed by cardiopulmonary resuscitation. A multimodal platform combining laser speckle imaging, ABP, and electroencephalography to monitor CBF, peripheral blood pressure, and brain electrophysiology, respectively, was used. CBF and ABP pulsatility and CVR were assessed during baseline, CA, and multiple time points after resuscitation. Neuroelectrical recovery, a surrogate for neurological outcome, was assessed using quantitative electroencephalography 90 minutes after resuscitation. We found that CBF pulsatility differs significantly from baseline at all experimental time points with sustained deficits during the 2 hours of postresuscitation monitoring, whereas ABP pulsatility was relatively unaffected. Alterations in CBF pulsatility were inversely correlated with changes in CVR, but ABP pulsatility had no association to CVR. Interestingly, despite small changes in ABP pulsatility, higher ABP pulsatility was associated with worse neuroelectrical recovery, whereas CBF pulsatility had no association. Conclusions Our results reveal, for the first time, that CBF pulsatility and CVR are significantly altered in the short‐term postresuscitation period after CA. Nevertheless, higher ABP pulsatility appears to be inversely associated with neuroelectrical recovery, possibly caused by impaired cerebral autoregulation and/or more severe global cerebral ischemia.
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Affiliation(s)
- Christian Crouzet
- Beckman Laser Institute and Medical Clinic Irvine CA.,Department of Biomedical Engineering University of California Irvine CA.,University of California, Irvine Irvine CA
| | - Robert H Wilson
- Beckman Laser Institute and Medical Clinic Irvine CA.,University of California, Irvine Irvine CA
| | - Donald Lee
- Department of Neurology University of California Irvine CA.,University of California, Irvine Irvine CA
| | - Afsheen Bazrafkan
- Department of Neurology University of California Irvine CA.,University of California, Irvine Irvine CA
| | - Bruce J Tromberg
- Beckman Laser Institute and Medical Clinic Irvine CA.,Department of Biomedical Engineering University of California Irvine CA.,Department of Surgery University of California Irvine CA.,University of California, Irvine Irvine CA
| | - Yama Akbari
- Beckman Laser Institute and Medical Clinic Irvine CA.,Department of Neurology University of California Irvine CA.,University of California, Irvine Irvine CA
| | - Bernard Choi
- Beckman Laser Institute and Medical Clinic Irvine CA.,Department of Biomedical Engineering University of California Irvine CA.,Department of Surgery University of California Irvine CA.,Edwards Lifesciences Center for Advanced Cardiovascular Technology Irvine CA.,University of California, Irvine Irvine CA
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Elting JWJ, Tas J, Aries MJ, Czosnyka M, Maurits NM. Dynamic cerebral autoregulation estimates derived from near infrared spectroscopy and transcranial Doppler are similar after correction for transit time and blood flow and blood volume oscillations. J Cereb Blood Flow Metab 2020; 40:135-149. [PMID: 30353763 PMCID: PMC6927073 DOI: 10.1177/0271678x18806107] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
We analysed mean arterial blood pressure, cerebral blood flow velocity, oxygenated haemoglobin and deoxygenated haemoglobin signals to estimate dynamic cerebral autoregulation. We compared macrovascular (mean arterial blood pressure-cerebral blood flow velocity) and microvascular (oxygenated haemoglobin-deoxygenated haemoglobin) dynamic cerebral autoregulation estimates during three different conditions: rest, mild hypocapnia and hypercapnia. Microvascular dynamic cerebral autoregulation estimates were created by introducing the constant time lag plus constant phase shift model, which enables correction for transit time, blood flow and blood volume oscillations (TT-BF/BV correction). After TT-BF/BV correction, a significant agreement between mean arterial blood pressure-cerebral blood flow velocity and oxygenated haemoglobin-deoxygenated haemoglobin phase differences in the low frequency band was found during rest (left: intraclass correlation=0.6, median phase difference 29.5° vs. 30.7°, right: intraclass correlation=0.56, median phase difference 32.6° vs. 39.8°) and mild hypocapnia (left: intraclass correlation=0.73, median phase difference 48.6° vs. 43.3°, right: intraclass correlation=0.70, median phase difference 52.1° vs. 61.8°). During hypercapnia, the mean transit time decreased and blood volume oscillations became much more prominent, except for very low frequencies. The transit time related to blood flow oscillations was remarkably stable during all conditions. We conclude that non-invasive microvascular dynamic cerebral autoregulation estimates are similar to macrovascular dynamic cerebral autoregulation estimates, after TT-BF/BV correction is applied. These findings may increase the feasibility of non-invasive continuous autoregulation monitoring and guided therapy in clinical situations.
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Affiliation(s)
- Jan Willem J Elting
- Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands
| | - Jeanette Tas
- Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands
| | - Marcel Jh Aries
- Department of Intensive Care, Maastricht University Medical Center, Maastricht, The Netherlands.,Brain Physics Group, Department of Clinical Neurosciences, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
| | - Marek Czosnyka
- Brain Physics Group, Department of Clinical Neurosciences, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK.,Institute of Electronic Systems, Warsaw University of Technology, Warsaw, Poland
| | - Natasha M Maurits
- Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands
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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: 10] [Impact Index Per Article: 2.0] [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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Mullen MT, Parthasarathy AB, Zandieh A, Baker WB, Mesquita RC, Loomis C, Torres J, Guo W, Favilla CG, Messé SR, Yodh AG, Detre JA, Kasner SE. Cerebral Blood Flow Response During Bolus Normal Saline Infusion After Ischemic Stroke. J Stroke Cerebrovasc Dis 2019; 28:104294. [PMID: 31416759 DOI: 10.1016/j.jstrokecerebrovasdis.2019.07.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 07/11/2019] [Indexed: 01/01/2023] Open
Abstract
GOALS We quantified cerebral blood flow response to a 500 cc bolus of 0.9%% normal saline (NS) within 96 hours of acute ischemic stroke (AIS) using diffuse correlation spectroscopy (DCS). MATERIALS AND METHODS Subjects with AIS in the anterior, middle, or posterior cerebral artery territory were enrolled within 96 hours of symptom onset. DCS measured relative cerebral blood flow (rCBF) in the bilateral frontal lobes for 15 minutes at rest (baseline), during a 30-minute infusion of 500 cc NS (bolus), and for 15 minutes after completion (post-bolus). Mean rCBF for each time period was calculated for individual subjects and median rCBF for the population was compared between time periods. Linear regression was used to evaluate for associations between rCBF and clinical features. RESULTS Among 57 subjects, median rCBF (IQR) increased relative to baseline in the ipsilesional hemisphere by 17% (-2.0%, 43.1%), P< 0.001, and in the contralesional hemisphere by 13.3% (-4.3%, 36.0%), P < .004. No significant associations were found between ipsilesional changes in rCBF and age, race, infarct size, infarct location, presence of large vessel stenosis, NIH stroke scale, or symptom duration. CONCLUSION A 500 cc bolus of .9% NS produced a measurable increase in rCBF in both the affected and nonaffected hemispheres. Clinical features did not predict rCBF response.
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Affiliation(s)
- Michael T Mullen
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania; Leondard David Institute for Health Economics, University of Pennsylvania, Philadelphia, Pennsylvania.
| | | | - Ali Zandieh
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Wesley B Baker
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Neurology, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | | | - Caitlin Loomis
- Department of Neurology, Yale University, New Haven, Connecticut
| | - Jose Torres
- Department of Neurology, New York University, New York City, New York
| | - Wensheng Guo
- Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | | | - Steven R Messé
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Arjun G Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania
| | - John A Detre
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Scott E Kasner
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania
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Baker WB, Balu R, He L, Kavuri VC, Busch DR, Amendolia O, Quattrone F, Frangos S, Maloney-Wilensky E, Abramson K, Mahanna Gabrielli E, Yodh AG, Andrew Kofke W. Continuous non-invasive optical monitoring of cerebral blood flow and oxidative metabolism after acute brain injury. J Cereb Blood Flow Metab 2019; 39:1469-1485. [PMID: 31088234 PMCID: PMC6681541 DOI: 10.1177/0271678x19846657] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Rapid detection of ischemic conditions at the bedside can improve treatment of acute brain injury. In this observational study of 11 critically ill brain-injured adults, we employed a monitoring approach that interleaves time-resolved near-infrared spectroscopy (TR-NIRS) measurements of cerebral oxygen saturation and oxygen extraction fraction (OEF) with diffuse correlation spectroscopy (DCS) measurement of cerebral blood flow (CBF). Using this approach, we demonstrate the clinical promise of non-invasive, continuous optical monitoring of changes in CBF and cerebral metabolic rate of oxygen (CMRO2). In addition, the optical CBF and CMRO2 measures were compared to invasive brain tissue oxygen tension (PbtO2), thermal diffusion flowmetry CBF, and cerebral microdialysis measures obtained concurrently. The optical CBF and CMRO2 information successfully distinguished between ischemic, hypermetabolic, and hyperemic conditions that arose spontaneously during patient care. Moreover, CBF monitoring during pressor-induced changes of mean arterial blood pressure enabled assessment of cerebral autoregulation. In total, the findings suggest that this hybrid non-invasive neurometabolic optical monitor (NNOM) can facilitate clinical detection of adverse physiological changes in brain injured patients that are otherwise difficult to measure with conventional bedside monitoring techniques.
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Affiliation(s)
- Wesley B Baker
- 1 Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA, USA.,2 Division of Neurology, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Ramani Balu
- 3 Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - Lian He
- 4 Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
| | - Venkaiah C Kavuri
- 4 Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
| | - David R Busch
- 4 Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA.,5 Department of Anesthesiology & Pain Management and Neurology & Neurotherapeutics, University of Texas Southwestern, Dallas, TX, USA
| | - Olivia Amendolia
- 6 Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Francis Quattrone
- 6 Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Suzanne Frangos
- 6 Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Kenneth Abramson
- 4 Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Arjun G Yodh
- 4 Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
| | - W Andrew Kofke
- 1 Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA, USA
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Forti RM, Favilla CG, Cochran JM, Baker WB, Detre JA, Kasner SE, Mullen MT, Messé SR, Kofke WA, Balu R, Kung D, Pukenas BA, Sedora-Roman NI, Hurst RW, Choudhri OA, Mesquita RC, Yodh AG. Transcranial Optical Monitoring of Cerebral Hemodynamics in Acute Stroke Patients during Mechanical Thrombectomy. J Stroke Cerebrovasc Dis 2019; 28:1483-1494. [PMID: 30975462 PMCID: PMC6686873 DOI: 10.1016/j.jstrokecerebrovasdis.2019.03.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 02/28/2019] [Accepted: 03/06/2019] [Indexed: 01/01/2023] Open
Abstract
INTRODUCTION Mechanical thrombectomy is revolutionizing treatment of acute stroke due to large vessel occlusion (LVO). Unfortunately, use of the modified Thrombolysis in Cerebral Infarction score (mTICI) to characterize recanalization of the cerebral vasculature does not address microvascular perfusion of the distal parenchyma, nor provide more than a vascular "snapshot." Thus, little is known about tissue-level hemodynamic consequences of LVO recanalization. Diffuse correlation spectroscopy (DCS) and diffuse optical spectroscopy (DOS) are promising methods for continuous, noninvasive, contrast-free transcranial monitoring of cerebral microvasculature. METHODS Here, we use a combined DCS/DOS system to monitor frontal lobe hemodynamic changes during endovascular treatment of 2 patients with ischemic stroke due to internal carotid artery (ICA) occlusions. RESULTS AND DISCUSSION The monitoring instrument identified a recanalization-induced increase in ipsilateral cerebral blood flow (CBF) with little or no concurrent change in contralateral CBF and extracerebral blood flow. The results suggest that diffuse optical monitoring is sensitive to intracerebral hemodynamics in patients with ICA occlusion and can measure microvascular responses to mechanical thrombectomy.
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Affiliation(s)
- Rodrigo M Forti
- Institute of Physics, University of Campinas, Campinas, SP, Brazil; Brazilian Institute of Neuroscience and Neurotechnology, Campinas, SP, Brazil; Department of Physics & Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania.
| | | | - Jeffrey M Cochran
- Department of Physics & Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Wesley B Baker
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - John A Detre
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Scott E Kasner
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Michael T Mullen
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Steven R Messé
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - W Andrew Kofke
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ramani Balu
- Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - David Kung
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Bryan A Pukenas
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Neda I Sedora-Roman
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Robert W Hurst
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Omar A Choudhri
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Rickson C Mesquita
- Institute of Physics, University of Campinas, Campinas, SP, Brazil; Brazilian Institute of Neuroscience and Neurotechnology, Campinas, SP, Brazil
| | - Arjun G Yodh
- Department of Physics & Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania
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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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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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