1
|
Liu X, Mohtasebi M, Safavi P, Fathi F, Haratbar SR, Chen L, Chen J, Bada HS, Chen L, Abu Jawdeh EG, Yu G. Wearable fiber-free optical sensor for continuous monitoring of neonatal cerebral blood flow and oxygenation. Pediatr Res 2024; 96:486-493. [PMID: 38503982 DOI: 10.1038/s41390-024-03137-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 02/15/2024] [Accepted: 03/01/2024] [Indexed: 03/21/2024]
Abstract
BACKGROUND Unstable cerebral hemodynamics places preterm infants at high risk of brain injury. We adapted an innovative, fiber-free, wearable diffuse speckle contrast flow-oximetry (DSCFO) device for continuous monitoring of both cerebral blood flow (CBF) and oxygenation in neonatal piglets and preterm infants. METHODS DSCFO uses two small laser diodes as focused-point and a tiny CMOS camera as a high-density two-dimensional detector to detect spontaneous spatial fluctuation of diffuse laser speckles for CBF measurement, and light intensity attenuations for cerebral oxygenation measurement. The DSCFO was first validated against the established diffuse correlation spectroscopy (DCS) in neonatal piglets and then utilized for continuous CBF and oxygenation monitoring in preterm infants during intermittent hypoxemia (IH) events. RESULTS Significant correlations between the DSCFO and DCS measurements of CBF variations in neonatal piglets were observed. IH events induced fluctuations in CBF, cerebral oxygenation, and peripheral cardiorespiratory vitals in preterm infants. However, no consistent correlation patterns were observed among peripheral and cerebral monitoring parameters. CONCLUSIONS This pilot study demonstrated the feasibility of DSCFO technology to serve as a low-cost wearable sensor for continuous monitoring of multiple cerebral hemodynamic parameters. The results suggested the importance of multi-parameter measurements for understanding deep insights of peripheral and cerebral regulations. IMPACT The innovative DSCFO technology may serve as a low-cost wearable sensor for continuous bedside monitoring of multiple cerebral hemodynamic parameters in neonatal intensive care units. Concurrent DSCFO and DCS measurements of CBF variations in neonatal piglet models generated consistent results. No consistent correlation patterns were observed among peripheral and cerebral monitoring parameters in preterm neonates, suggesting the importance of multi-parameter measurements for understanding deep insights of peripheral and cerebral regulations during IH events. Integrating and correlating multiple cerebral functional parameters with clinical outcomes may identify biomarkers for prediction and management of IH associated brain injury.
Collapse
Affiliation(s)
- Xuhui Liu
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Mehrana Mohtasebi
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Pegah Safavi
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Faraneh Fathi
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | | | - Li Chen
- Biostatistics and Bioinformatics Shared Resource Facility, Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - Jin Chen
- Department of Internal Medicine and Department of Computer Science, Institute for Biomedical Informatics, University of Kentucky, Lexington, KY, USA
| | - Henrietta S Bada
- Division of Neonatology, Department of Pediatrics, University of Kentucky, Lexington, KY, USA
| | - Lei Chen
- Department of Physiology and the Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY, USA
| | - Elie G Abu Jawdeh
- Division of Neonatology, Department of Pediatrics, University of Kentucky, Lexington, KY, USA
| | - Guoqiang Yu
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA.
| |
Collapse
|
2
|
Huang YX, Mahler S, Dickson M, Abedi A, Tyszka JM, Lo YT, Russin J, Liu C, Yang C. Compact and cost-effective laser-powered speckle contrast optical spectroscopy fiber-free device for measuring cerebral blood flow. JOURNAL OF BIOMEDICAL OPTICS 2024; 29:067001. [PMID: 38826808 PMCID: PMC11140771 DOI: 10.1117/1.jbo.29.6.067001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 04/22/2024] [Accepted: 05/15/2024] [Indexed: 06/04/2024]
Abstract
Significance In the realm of cerebrovascular monitoring, primary metrics typically include blood pressure, which influences cerebral blood flow (CBF) and is contingent upon vessel radius. Measuring CBF noninvasively poses a persistent challenge, primarily attributed to the difficulty of accessing and obtaining signal from the brain. Aim Our study aims to introduce a compact speckle contrast optical spectroscopy device for noninvasive CBF measurements at long source-to-detector distances, offering cost-effectiveness, and scalability while tracking blood flow (BF) with remarkable sensitivity and temporal resolution. Approach The wearable sensor module consists solely of a laser diode and a board camera. It can be easily placed on a subject's head to measure BF at a sampling rate of 80 Hz. Results Compared to the single-fiber-based version, the proposed device achieved a signal gain of about 70 times, showed superior stability, reproducibility, and signal-to-noise ratio for measuring BF at long source-to-detector distances. The device can be distributed in multiple configurations around the head. Conclusions Given its cost-effectiveness, scalability, and simplicity, this laser-centric tool offers significant potential in advancing noninvasive cerebral monitoring technologies.
Collapse
Affiliation(s)
- Yu Xi Huang
- California Institute of Technology, Department of Electrical Engineering, Pasadena, California, United States
| | - Simon Mahler
- California Institute of Technology, Department of Electrical Engineering, Pasadena, California, United States
| | - Maya Dickson
- California Institute of Technology, Department of Electrical Engineering, Pasadena, California, United States
| | - Aidin Abedi
- University of Southern California, USC Neurorestoration Center, Department of Neurological Surgery, Los Angeles, California, United States
| | - Julian Michael Tyszka
- California Institute of Technology, Division of Humanities and Social Sciences, Pasadena, California, United States
| | - Yu Tung Lo
- University of Southern California, USC Neurorestoration Center, Department of Neurological Surgery, Los Angeles, California, United States
| | - Jonathan Russin
- University of Southern California, USC Neurorestoration Center, Department of Neurological Surgery, Los Angeles, California, United States
- Rancho Los Amigos National Rehabilitation Center, Downey, California, United States
| | - Charles Liu
- University of Southern California, USC Neurorestoration Center, Department of Neurological Surgery, Los Angeles, California, United States
- Rancho Los Amigos National Rehabilitation Center, Downey, California, United States
| | - Changhuei Yang
- California Institute of Technology, Department of Electrical Engineering, Pasadena, California, United States
| |
Collapse
|
3
|
Favilla CG, Carter S, Hartl B, Gitlevich R, Mullen MT, Yodh AG, Baker WB, Konecky S. Validation of the Openwater wearable optical system: cerebral hemodynamic monitoring during a breath-hold maneuver. NEUROPHOTONICS 2024; 11:015008. [PMID: 38464864 PMCID: PMC10923543 DOI: 10.1117/1.nph.11.1.015008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 02/10/2024] [Accepted: 02/13/2024] [Indexed: 03/12/2024]
Abstract
Significance Bedside cerebral blood flow (CBF) monitoring has the potential to inform and improve care for acute neurologic diseases, but technical challenges limit the use of existing techniques in clinical practice. Aim Here, we validate the Openwater optical system, a novel wearable headset that uses laser speckle contrast to monitor microvascular hemodynamics. Approach We monitored 25 healthy adults with the Openwater system and concurrent transcranial Doppler (TCD) while performing a breath-hold maneuver to increase CBF. Relative blood flow (rBF) was derived from changes in speckle contrast, and relative blood volume (rBV) was derived from changes in speckle average intensity. Results A strong correlation was observed between beat-to-beat optical rBF and TCD-measured cerebral blood flow velocity (CBFv), R = 0.79 ; the slope of the linear fit indicates good agreement, 0.87 (95% CI: 0.83 - 0.92 ). Beat-to-beat rBV and CBFv were also strongly correlated, R = 0.72 , but as expected the two variables were not proportional; changes in rBV were smaller than CBFv changes, with linear fit slope of 0.18 (95% CI: 0.17 to 0.19). Further, strong agreement was found between rBF and CBFv waveform morphology and related metrics. Conclusions This first in vivo validation of the Openwater optical system highlights its potential as a cerebral hemodynamic monitor, but additional validation is needed in disease states.
Collapse
Affiliation(s)
- Christopher G. Favilla
- University of Pennsylvania, Department of Neurology, Philadelphia, Pennsylvania, United States
| | - Sarah Carter
- University of Pennsylvania, Department of Neurology, Philadelphia, Pennsylvania, United States
| | - Brad Hartl
- Openwater, San Francisco, California, United States
| | - Rebecca Gitlevich
- University of Pennsylvania, Department of Neurology, Philadelphia, Pennsylvania, United States
| | - Michael T. Mullen
- Temple University, Department of Neurology, Philadelphia, Pennsylvania, United States
| | - Arjun G. Yodh
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
| | - Wesley B. Baker
- Children’s Hospital of Philadelphia, Department of Neurology, Philadelphia, Pennsylvania, United States
| | | |
Collapse
|
4
|
Liu X, Irwin DA, Huang C, Gu Y, Chen L, Donohue KD, Chen L, Yu G. A Wearable Fiber-Free Optical Sensor for Continuous Monitoring of Cerebral Blood Flow in Freely Behaving Mice. IEEE Trans Biomed Eng 2023; 70:1838-1848. [PMID: 37015409 PMCID: PMC10542964 DOI: 10.1109/tbme.2022.3229513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Wearable technologies for functional brain monitoring in freely behaving subjects can advance our understanding of cognitive processing and adaptive behavior. Existing technologies are lacking in this capability or need procedures that are invasive and/or otherwise impede brain assessments during social behavioral conditions, exercise, and sleep. METHODS In response a complete system was developed to combine relative cerebral blood flow (rCBF) measurement, O2 and CO2 supplies, and behavior recording for use on conscious, freely behaving mice. An innovative diffuse speckle contrast flowmetry (DSCF) device and associated hardware were miniaturized and optimized for rCBF measurements in small subject applications. The use of this wearable, fiber-free, near-infrared DSCF head-stage/probe allowed no craniotomy, minimally invasive probe implantation, and minimal restraint of the awake animal. RESULTS AND CONCLUSIONS Significant correlations were found between measurements with the new DSCF design and an optical standard. The system successfully detected rCBF responses to CO2-induced hypercapnia in both anesthetized and freely behaving mice. SIGNIFICANCE Collecting rCBF and activity information together during natural behaviors provides realistic physiological results and opens the path to exploring their correlations with pathophysiological conditions.
Collapse
Affiliation(s)
- Xuhui Liu
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Daniel A. Irwin
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Chong Huang
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Yutong Gu
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Li Chen
- Biostatistics and Bioinformatics Shared Resource Facility, Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - Kevin D. Donohue
- Department of Electrical and Computer Engineering, University of Kentucky, Lexington, KY, USA
| | - Lei Chen
- Department of Physiology, Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY, USA
| | - Guoqiang Yu
- Department of Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| |
Collapse
|
5
|
Development of a miniaturized and modular probe for fNIRS instrument. Lasers Med Sci 2022; 37:2269-2277. [PMID: 35028765 DOI: 10.1007/s10103-021-03493-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 11/29/2021] [Indexed: 10/19/2022]
Abstract
Functional near-infrared spectroscopy (fNIRS) is a non-invasive and promising method for continuously monitoring hemodynamic and metabolic changes in tissues. However, the existing fNIRS equipment uses optical fiber, which is bulky, expensive, and time-consuming. We present a miniaturized, modular, novel silicon photomultiplier (SiPM) detector and develop a fNIRS instrument aimed at investigating the cerebral hemodynamic response for patients with epilepsy. Light emitting probe is a circle with a diameter of 5 mm. Independent and modular light source and detector are more flexible in placement. The system can be expanded to high-density measurement with 16 light sources, 16 detectors, and 52 channels. The sampling rate of each channel is 25 Hz. Instrument performance was evaluated using brain tissue phantom and in vivo experiments. High signal-to-noise ratio (60 dB) in source detector separation (SDS) of 30 mm, good stability (0.1%), noise equivalent power (0.89 pW), and system drift (0.56%) were achieved in the phantom experiment. Forearm blood-flow occlusion experiments were performed on the forearm of three healthy volunteers to demonstrate the ability to track rapid hemodynamic changes. Breath holding experiments on the forehead of healthy volunteers demonstrated the system can well detect brain function activity. The computer software was developed to display the original light signal intensity and the concentration changes of oxygenated hemoglobin (HbO2) and deoxygenated hemoglobin (HbR) in real time. This system paves the way for our further diagnosis of epilepsy.
Collapse
|
6
|
Manikkath J, Subramony JA. Toward closed-loop drug delivery: Integrating wearable technologies with transdermal drug delivery systems. Adv Drug Deliv Rev 2021; 179:113997. [PMID: 34634396 DOI: 10.1016/j.addr.2021.113997] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 08/31/2021] [Accepted: 10/04/2021] [Indexed: 12/15/2022]
Abstract
The recent advancement and prevalence of wearable technologies and their ability to make digital measurements of vital signs and wellness parameters have triggered a new paradigm in the management of diseases. Drug delivery as a function of stimuli or response from wearable, closed-loop systems can offer real-time on-demand or preprogrammed drug delivery capability and offer total management of disease states. Here we review the key opportunities in this space for development of closed-loop systems, given the advent of digital wearable technologies. Particular considerations and focus are given to closed-loop systems combined with transdermal drug delivery technologies.
Collapse
|
7
|
Biswas A, Moka S, Muller A, Parthasarathy AB. Fast diffuse correlation spectroscopy with a low-cost, fiber-less embedded diode laser. BIOMEDICAL OPTICS EXPRESS 2021; 12:6686-6700. [PMID: 34858674 PMCID: PMC8606156 DOI: 10.1364/boe.435136] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 09/20/2021] [Accepted: 09/21/2021] [Indexed: 06/02/2023]
Abstract
Diffuse correlation spectroscopy (DCS), a popular optical technique for fast noninvasive measurement of blood flow, is commonly implemented using expensive fiber-coupled long coherence length laser systems. Here, we report the development of a portable and fiber-less approach that can be used as a low-cost alternative to illuminate tissue in DCS instruments. We validate the accuracy and noise characteristics of the fiber-less DCS laser source, by comparisons against traditional DCS light sources, with experiments on controlled tissue-simulating phantoms and in humans.
Collapse
Affiliation(s)
- Arindam Biswas
- Department of Electrical Engineering, University of South Florida, 4202 E. Fowler Avenue, ENG030, Tampa, FL 33620, USA
| | - Sadhu Moka
- Department of Electrical Engineering, University of South Florida, 4202 E. Fowler Avenue, ENG030, Tampa, FL 33620, USA
| | - Andreas Muller
- Department of Physics, University of South Florida, 4202 E. Fowler Avenue, ISA2019, Tampa, FL 33620, USA
| | - Ashwin B. Parthasarathy
- Department of Electrical Engineering, University of South Florida, 4202 E. Fowler Avenue, ENG030, Tampa, FL 33620, USA
| |
Collapse
|
8
|
Zhao M, Huang C, Mazdeyasna S, Yu G. Extraction of tissue optical property and blood flow from speckle contrast diffuse correlation tomography (scDCT) measurements. BIOMEDICAL OPTICS EXPRESS 2021; 12:5894-5908. [PMID: 34692223 PMCID: PMC8515985 DOI: 10.1364/boe.429890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/15/2021] [Accepted: 08/17/2021] [Indexed: 06/13/2023]
Abstract
Measurement of blood flow in tissue provides vital information for the diagnosis and therapeutic monitoring of various vascular diseases. A noncontact, camera-based, near-infrared speckle contrast diffuse correlation tomography (scDCT) technique has been recently developed for 3D imaging of blood flow index (αDB) distributions in deep tissues up to a centimeter. A limitation with the continuous-wave scDCT measurement of blood flow is the assumption of constant and homogenous tissue absorption coefficient (μ a ). The present study took the advantage of rapid, high-density, noncontact scDCT measurements of both light intensities and diffuse speckle contrast at multiple source-detector distances and developed two-step fitting algorithms for extracting both μ a and αDB. The new algorithms were tested in tissue-simulating phantoms with known optical properties and human forearms. Measurement results were compared against established near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS) techniques. The accuracies of our new fitting algorithms with scDCT measurements in phantoms (up to 16% errors) and forearms (up to 23% errors) are comparable to relevant study results (up to 25% errors). Knowledge of μ a not only improved the accuracy in calculating αDB but also provided the potential for quantifying tissue blood oxygenation via spectral measurements. A multiple-wavelength scDCT system with new algorithms is currently developing to fit multi-wavelength and multi-distance data for 3D imaging of both blood flow and oxygenation distributions in deep tissues.
Collapse
|
9
|
Li Z, Ge Q, Feng J, Jia K, Zhao J. Quantification of blood flow index in diffuse correlation spectroscopy using long short-term memory architecture. BIOMEDICAL OPTICS EXPRESS 2021; 12:4131-4146. [PMID: 34457404 PMCID: PMC8367234 DOI: 10.1364/boe.423777] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 06/08/2021] [Accepted: 06/08/2021] [Indexed: 05/30/2023]
Abstract
Diffuse correlation spectroscopy (DCS) is a noninvasive technique that derives blood flow information from measurements of the temporal intensity fluctuations of multiply scattered light. Blood flow index (BFI) and especially its variation was demonstrated to be approximately proportional to absolute blood flow. We investigated and assessed the utility of a long short-term memory (LSTM) architecture for quantification of BFI in DCS. Phantom and in vivo experiments were established to measure normalized intensity autocorrelation function data. Improved accuracy and faster computational time were gained by the proposed LSTM architecture. The results support the notion of using proposed LSTM architecture for quantification of BFI in DCS. This approach would be especially useful for continuous real-time monitoring of blood flow.
Collapse
Affiliation(s)
- Zhe Li
- Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China
- Beijing Laboratory of Advanced Information Networks, Beijing 100124, China
- Beijing Key Laboratory of Computational Intelligence and Intelligent System, Beijing University of Technology, Beijing 100124, China
- Zhe Li and Qisi Ge contributed equally to this work
| | - Qisi Ge
- Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China
- Beijing Laboratory of Advanced Information Networks, Beijing 100124, China
- Beijing Key Laboratory of Computational Intelligence and Intelligent System, Beijing University of Technology, Beijing 100124, China
- Zhe Li and Qisi Ge contributed equally to this work
| | - Jinchao Feng
- Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China
- Beijing Laboratory of Advanced Information Networks, Beijing 100124, China
- Beijing Key Laboratory of Computational Intelligence and Intelligent System, Beijing University of Technology, Beijing 100124, China
| | - Kebin Jia
- Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China
- Beijing Laboratory of Advanced Information Networks, Beijing 100124, China
- Beijing Key Laboratory of Computational Intelligence and Intelligent System, Beijing University of Technology, Beijing 100124, China
| | - Jing Zhao
- College of Pharmaceutical Engineering of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, China
| |
Collapse
|