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Dubensky A, Ryzhkov I, Tsokolaeva Z, Lapin K, Kalabushev S, Varnakova L, Dolgikh V. Post-occlusive reactive hyperemia variables can be used to diagnose vascular dysfunction in hemorrhagic shock. Microvasc Res 2024; 152:104647. [PMID: 38092223 DOI: 10.1016/j.mvr.2023.104647] [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: 10/16/2023] [Revised: 11/24/2023] [Accepted: 12/08/2023] [Indexed: 02/03/2024]
Abstract
INTRODUCTION Laser doppler flowmetry (LDF) allows non-invasive assessment of microvascular functions. The combination of LDF with an occlusion functional test enables study of post-occlusive reactive hyperemia (PORH), providing additional information about vasomotor function, capillary blood flow reserve, and the overall reactivity of the microvascular system. AIM To identify early alterations of PORH variables in the skin of a rat in hemorrhagic shock (HS). MATERIAL AND METHODS Male Wistar rats (n = 14) weighing 400-450 g were anesthetized with a combination of tiletamine/zolazepam (20 mg/kg) and xylazine (5 mg/kg). The animals breathed on their own, and were placed on a heated platform in the supine position. A PE-50 catheter was inserted into the carotid artery to measure the mean arterial pressure (MAP). The optical probe of the Laser Doppler device was installed on the plantar surface of the hind limb of a rat; a pneumatic cuff was applied proximal to the same limb. The occlusion time was 3 min. The following physiological variables were measured at baseline and 30 min after blood loss: MAP, mmHg; mean cutaneous blood flow (M, PU); cutaneous vascular conductance (CVC = M/MAP); peak hyperemia (Mmax, PU) and maximum cutaneous vascular conductance (CVCmax) during PORH. In the HS group (n = 7), 30 % of the estimated blood volume was taken within 5 min. There was no blood loss in the group of sham-operated animals (Sham, n = 7). The results are presented as Me [25 %;75 %]. The U-Mann-Whitney criterion was used to evaluate intergroup differences. Differences were considered statistically significant at p < 0.05. RESULTS The groups did not differ at baseline. Blood loss led to a significant decrease in MAP (43 [31;46] vs. 94 [84;104] mmHg), M (11.5 [16.9;7.8] vs 16.7 [20.2;13.9]) and Mmax (18.1 [16.4;21.8] vs. 25.0 [23.0;26.2]) in the HS group compared to the Sham group, respectively. At the same time, both CVC (0.25 [0.23;0.30] vs. 0.16 [0.14;0.21]) and CVCmax (0.55 [0.38;0.49] vs 0.24 [0.23; 0.29]) increased after blood loss in the HS group compared to the Sham group. Arterial blood gas analysis revealed metabolic lactic acidosis in the HS group. CONCLUSION In this rat model of HS, alterations in cutaneous blood flow are manifested by a decrease in perfusion (M) and the intensity of PORH (Mmax) with a simultaneous increase in vascular conductance (CVC and CVCmax).
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Affiliation(s)
- Aleksey Dubensky
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia
| | - Ivan Ryzhkov
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia.
| | - Zoya Tsokolaeva
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia
| | - Konstantin Lapin
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia.
| | - Sergey Kalabushev
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia.
| | - Lidia Varnakova
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia.
| | - Vladimir Dolgikh
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia
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Makovik I, Volkov M, Eratova L, Dremin V. Vascular targeted optical theranostics: enhanced photoplethysmography imaging of laser-induced singlet oxygen effects. OPTICS LETTERS 2024; 49:1137-1140. [PMID: 38426957 DOI: 10.1364/ol.513960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 01/22/2024] [Indexed: 03/02/2024]
Abstract
The work considers a theranostic system that implements a multimodal approach allowing the simultaneous generation of singlet oxygen and visualization of the various parameters of the vascular bed. The system, together with the developed data processing algorithm, has the ability to assess architectural changes in the vascular network and its blood supply, as well as to identify periodic signal changes associated with mechanisms of blood flow oscillation of various natures. The use of this system seems promising in studying the effect of laser-induced singlet oxygen on the state of the vascular bed, as well as within the framework of the theranostic concept of treatment and diagnosis of oncological diseases and non-oncological vascular anomalies.
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Yao J, Sprick JD, Jeong J, Park J, Reiter DA. Differences in peripheral microcirculatory blood flow regulation in chronic kidney disease based on wavelet analysis of resting near-infrared spectroscopy. Microvasc Res 2024; 151:104624. [PMID: 37926135 PMCID: PMC11018197 DOI: 10.1016/j.mvr.2023.104624] [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: 08/11/2023] [Revised: 10/13/2023] [Accepted: 11/01/2023] [Indexed: 11/07/2023]
Abstract
Vascular impairment is closely related to increased mortality in chronic kidney disease (CKD). The objective of this study was to assess impairments in the regulation of peripheral microvascular perfusion in patients with CKD based on time-frequency spectral analysis of resting near-infrared spectroscopy (NIRS) signals. Total hemoglobin (tHb) concentration and tissue saturation index (TSI) signals were collected using NIRS for a continuous 5 mins at 10 Hz from the forearm of 55 participants (34 CKD including 5 with end-stage renal disease, and 21 age-matched control). Continuous wavelet transform-based spectral analysis was used to quantify the spectral amplitude within five pre-defined frequency intervals (I, 0.0095-0.021 Hz; II, 0.021-0.052 Hz; III, 0.052-0.145 Hz; IV, 0.145-0.6 Hz and V, 0.6-2.0 Hz), representing endothelial, neurogenic, myogenic, respiratory and heartbeat activity, respectively. CKD patients showed lower tHb average spectral amplitude within the neurogenic frequency interval compared with controls (p = 0.014), consistent with an increased sympathetic outflow observed in CKD. CKD patients also showed lower TSI average spectral amplitude within the endothelial frequency interval compared with controls (p = 0.046), consistent with a reduced endothelial function in CKD. These findings demonstrate the potential of wavelet analysis of NIRS to provide complementary information on peripheral microvascular regulation in CKD.
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Affiliation(s)
- Jingting Yao
- Department of Radiology and Imaging Science, Emory University, Atlanta, GA, United States; Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | - Justin D Sprick
- Department of Kinesiology, Health Promotion, and Recreation, University of North Texas, Denton, TX, United States
| | - Jinhee Jeong
- Division of Renal Medicine, Emory University, Atlanta, GA, United States; Atlanta Veterans Affairs Medical Center, Decatur, GA, United States
| | - Jeanie Park
- Division of Renal Medicine, Emory University, Atlanta, GA, United States; Atlanta Veterans Affairs Medical Center, Decatur, GA, United States
| | - David A Reiter
- Department of Radiology and Imaging Science, Emory University, Atlanta, GA, United States; Department of Orthopedics, Emory University, Atlanta, GA, United States; Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, United States.
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Park JY, Choi G, Lee K. Pressure stimulus study on acupuncture points with multi-channel multimode-fiber diffuse speckle contrast analysis (MMF-DSCA). BIOMEDICAL OPTICS EXPRESS 2023; 14:5602-5614. [PMID: 38021125 PMCID: PMC10659788 DOI: 10.1364/boe.502447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 09/26/2023] [Accepted: 10/01/2023] [Indexed: 12/01/2023]
Abstract
A multi-channel multimode-fiber deep tissue flowmetry system has been constructed based on diffuse speckle contrast analysis (DSCA) for simultaneous blood flow measurements at different locations on the human body. This system has been utilized in an acupuncture study within the field of traditional Chinese medicine (TCM), primarily focusing on acupuncture points along the large intestine meridian. Deep tissue blood flow was monitored at four different acupuncture points (LI1, LI5, LI10, and ST25) with a sampling rate of 60 Hz while applying pressure stimulus on LI4 (hegu or hapgok). Although the blood flow index (BFI) and blood volume (BV) did not exhibit significant changes after the pressure stimulus, an increase in the amplitude and complexity of low-frequency oscillations (LFOs) in microcirculation was observed.
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Affiliation(s)
- Jae Yoon Park
- Department of Electrical Engineering and Computer Science, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Gisoon Choi
- Department of Electrical Engineering and Computer Science, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Kijoon Lee
- Department of Electrical Engineering and Computer Science, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
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Li D, Yao Y, Zuo T, Xu J, Tao C, Qian X, Liu X. In vivo structural and functional imaging of human nailbed microvasculature using photoacoustic microscopy. OPTICS LETTERS 2023; 48:5711-5714. [PMID: 37910740 DOI: 10.1364/ol.502305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 10/12/2023] [Indexed: 11/03/2023]
Abstract
Monitoring microvascular structure and function is of great significance for the diagnosis of many diseases. In this study, we demonstrate the feasibility of OR-PAM to nailbed microcirculation detection as a new, to the best of our knowledge, application scenario in humans. We propose a dual-wavelength optical-resolution photoacoustic microscopy (OR-PAM) with improved local-flexible coupling to image human nailbed microvasculature. Microchip lasers with 532 nm wavelength are employed as the pump sources. The 558 nm laser is generated from the 532 nm laser through the stimulated Raman scattering effect. The flowing water, circulated by a peristaltic pump, maintains the acoustic coupling between the ultrasonic transducer and the sample. These designs improve the sensitivity, practicality, and stability of the OR-PAM system for human in vivo experiments. The imaging of the mouse ear demonstrates the ability of our system to acquire structural and functional information. Then, the system is applied to image human nailbed microvasculature. The imaging results reveal that the superficial capillaries are arranged in a straight sagittal pattern, approximately parallel to the long axis of the finger. The arterial and venular limbs are distinguished according to their oxygen saturation differences. Additionally, the images successfully discover the capillary loops with single or multiple twists, the oxygen release at the end of the capillary loop, and the changes when the nailbed is abnormal.
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Dremin V. Lesion Detection and Analysis Using Optical Imaging. Diagnostics (Basel) 2023; 13:diagnostics13091565. [PMID: 37174956 PMCID: PMC10177594 DOI: 10.3390/diagnostics13091565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
The biomedical application of optical spectroscopy and imaging is currently an active, developing area of research, supported by recent technical progress in the development of light sources and detectors [...].
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Affiliation(s)
- Viktor Dremin
- Research & Development Center of Biomedical Photonics, Orel State University, 302026 Orel, Russia
- College of Engineering and Physical Sciences, Aston University, Birmingham B4 7ET, UK
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Karseeva E, Kolokolnikov I, Medvedeva E, Savchenko E. Joint Methodology Based on Optical Densitometry and Dynamic Light Scattering for Liver Function Assessment. Diagnostics (Basel) 2023; 13:diagnostics13071269. [PMID: 37046487 PMCID: PMC10092963 DOI: 10.3390/diagnostics13071269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/12/2023] [Accepted: 03/13/2023] [Indexed: 03/30/2023] Open
Abstract
A pressing health problem, both in clinical and socio-economic terms, is the increase in the number of patients with liver damage caused by viral diseases (hepatitis), cancer, toxicological damage, or metabolic disorders. Liver function assessment is a complex task, for which various existing diagnostic methods are used. Unfortunately, they all have several limitations which frequently make prompt and accurate diagnosis impossible. The high level of disability and mortality caused by liver diseases makes the development of new liver diagnostic methods very urgent. In this paper, we describe a new joint methodology for studying liver function based on optical densitometry and dynamic light scattering. This will help to diagnose and predict the dynamics of liver function during treatment with greater efficiency, due to including in consideration the individual characteristics of the cardiovascular system and tissue metabolism. In this paper, we present a laboratory model of a combined sensor for optical densitometry and dynamic light scattering. We also developed special software for controlling the sensor and processing the recorded data. Modeling experiments and physical medical studies were carried out to adjust and calibrate the sensor and software. We also assessed the sensor resolution when registering the concentration of dye in the human body and the minimum measured flow rate.
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Affiliation(s)
- Elina Karseeva
- Higher School of Applied Physics and Space Technologies, Institute of Electronics and Telecommunications, Peter the Great St. Petersburg Polytechnic University, Saint Petersburg 195251, Russia
- Correspondence: (E.K.); (I.K.); (E.M.)
| | - Ilya Kolokolnikov
- Higher School of Applied Physics and Space Technologies, Institute of Electronics and Telecommunications, Peter the Great St. Petersburg Polytechnic University, Saint Petersburg 195251, Russia
- Correspondence: (E.K.); (I.K.); (E.M.)
| | - Ekaterina Medvedeva
- Higher School of Applied Physics and Space Technologies, Institute of Electronics and Telecommunications, Peter the Great St. Petersburg Polytechnic University, Saint Petersburg 195251, Russia
- Correspondence: (E.K.); (I.K.); (E.M.)
| | - Elena Savchenko
- Computer Information Systems Department, International University of Kyrgyzstan, Bishkek 720010, Kyrgyzstan
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Hultman M, Larsson M, Strömberg T, Fredriksson I. Speed-resolved perfusion imaging using multi-exposure laser speckle contrast imaging and machine learning. JOURNAL OF BIOMEDICAL OPTICS 2023; 28:036007. [PMID: 36950019 PMCID: PMC10027009 DOI: 10.1117/1.jbo.28.3.036007] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 02/27/2023] [Indexed: 05/19/2023]
Abstract
SIGNIFICANCE Laser speckle contrast imaging (LSCI) gives a relative measure of microcirculatory perfusion. However, due to the limited information in single-exposure LSCI, models are inaccurate for skin tissue due to complex effects from e.g. static and dynamic scatterers, multiple Doppler shifts, and the speed-distribution of blood. It has been demonstrated how to account for these effects in laser Doppler flowmetry (LDF) using inverse Monte Carlo (MC) algorithms. This allows for a speed-resolved perfusion measure in absolute units %RBC × mm/s, improving the physiological interpretation of the data. Until now, this has been limited to a single-point LDF technique but recent advances in multi-exposure LSCI (MELSCI) enable the analysis in an imaging modality. AIM To present a method for speed-resolved perfusion imaging in absolute units %RBC × mm/s, computed from multi-exposure speckle contrast images. APPROACH An artificial neural network (ANN) was trained on a large simulated dataset of multi-exposure contrast values and corresponding speed-resolved perfusion. The dataset was generated using MC simulations of photon transport in randomized skin models covering a wide range of physiologically relevant geometrical and optical tissue properties. The ANN was evaluated on in vivo data sets captured during an occlusion provocation. RESULTS Speed-resolved perfusion was estimated in the three speed intervals 0 to 1 mm / s , 1 to 10 mm / s , and > 10 mm / s , with relative errors 9.8%, 12%, and 19%, respectively. The perfusion had a linear response to changes in both blood tissue fraction and blood flow speed and was less affected by tissue properties compared with single-exposure LSCI. The image quality was subjectively higher compared with LSCI, revealing previously unseen macro- and microvascular structures. CONCLUSIONS The ANN, trained on modeled data, calculates speed-resolved perfusion in absolute units from multi-exposure speckle contrast. This method facilitates the physiological interpretation of measurements using MELSCI and may increase the clinical impact of the technique.
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Affiliation(s)
- Martin Hultman
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
- Perimed AB, Stockholm, Sweden
- Address all correspondence to Martin Hultman,
| | - Marcus Larsson
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
| | - Tomas Strömberg
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
| | - Ingemar Fredriksson
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
- Perimed AB, Stockholm, Sweden
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Taylor-Williams M, Spicer G, Bale G, Bohndiek SE. Noninvasive hemoglobin sensing and imaging: optical tools for disease diagnosis. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:JBO-220074VR. [PMID: 35922891 PMCID: PMC9346606 DOI: 10.1117/1.jbo.27.8.080901] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 06/27/2022] [Indexed: 05/08/2023]
Abstract
SIGNIFICANCE Measurement and imaging of hemoglobin oxygenation are used extensively in the detection and diagnosis of disease; however, the applied instruments vary widely in their depth of imaging, spatiotemporal resolution, sensitivity, accuracy, complexity, physical size, and cost. The wide variation in available instrumentation can make it challenging for end users to select the appropriate tools for their application and to understand the relative limitations of different methods. AIM We aim to provide a systematic overview of the field of hemoglobin imaging and sensing. APPROACH We reviewed the sensing and imaging methods used to analyze hemoglobin oxygenation, including pulse oximetry, spectral reflectance imaging, diffuse optical imaging, spectroscopic optical coherence tomography, photoacoustic imaging, and diffuse correlation spectroscopy. RESULTS We compared and contrasted the ability of different methods to determine hemoglobin biomarkers such as oxygenation while considering factors that influence their practical application. CONCLUSIONS We highlight key limitations in the current state-of-the-art and make suggestions for routes to advance the clinical use and interpretation of hemoglobin oxygenation information.
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Affiliation(s)
- Michaela Taylor-Williams
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Cancer Research UK Cambridge Institute, Cambridge, United Kingdom, United Kingdom
| | - Graham Spicer
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Cancer Research UK Cambridge Institute, Cambridge, United Kingdom, United Kingdom
| | - Gemma Bale
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Electrical Division, Department of Engineering, Cambridge, United Kingdom, United Kingdom
| | - Sarah E Bohndiek
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Cancer Research UK Cambridge Institute, Cambridge, United Kingdom, United Kingdom
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Machikhin AS, Volkov MV, Khokhlov DD, Lovchikova ED, Potemkin AV, Danilycheva IV, Dorofeeva IV, Shulzhenko AE. Exoscope-based videocapillaroscopy system for in vivo skin microcirculation imaging of various body areas. BIOMEDICAL OPTICS EXPRESS 2021; 12:4627-4636. [PMID: 34513213 PMCID: PMC8407810 DOI: 10.1364/boe.420786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 06/20/2021] [Accepted: 06/23/2021] [Indexed: 06/13/2023]
Abstract
The capillary system immediately responds to many pathologies and environmental conditions. Accurate monitoring of its functioning often enables early detection of various diseases related to disorders in skin microcirculation. To expand the scope of capillaroscopy application, it is reasonable to visualize and assess blood microcirculation exactly in the areas of inflamed skin. Body vibrations, breathing, non-flat skin surface and other factors hamper the application of conventional capillaroscopes outside the nailfold area. In this paper, we propose an exoscope-based optical system for high-quality non-invasive computational imaging of capillary network in various areas of the body. Accurate image matching and tracking temporal intensity variations allow detecting the presence of blood pulsations, precise mapping of capillaries and photoplethysmogram acquisition. We have demonstrated the efficiency of the proposed approach experimentally by in vivo mapping and analysis of microvessels in wrist, forearm, upper-arm, breast and hip areas. We believe that the developed system will increase the diagnostic value of video capillaroscopy in clinical practice.
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Affiliation(s)
- Alexander S. Machikhin
- Laboratory of Acousto-optic Spectroscopy, Scientific and Technological Center of Unique Instrumentation, Russian Academy of Sciences, 15 Butlerova, 117342, Moscow, Russia
| | - Mikhail V. Volkov
- Faculty of Applied Optics, ITMO University, 49 Kronverksky, 197101, St. Petersburg, Russia
| | - Demid D. Khokhlov
- Laboratory of Acousto-optic Spectroscopy, Scientific and Technological Center of Unique Instrumentation, Russian Academy of Sciences, 15 Butlerova, 117342, Moscow, Russia
| | - Ekaterina D. Lovchikova
- Laboratory of Acousto-optic Spectroscopy, Scientific and Technological Center of Unique Instrumentation, Russian Academy of Sciences, 15 Butlerova, 117342, Moscow, Russia
| | - Andrey V. Potemkin
- Faculty of Applied Optics, ITMO University, 49 Kronverksky, 197101, St. Petersburg, Russia
| | - Inna V. Danilycheva
- Department of Allergology and Immunotherapy, Institute of Immunology, Federal Medical Biological Agency, 24 Kashirskoe, 115522, Moscow, Russia
| | - Irina V. Dorofeeva
- Department of Allergology and Immunotherapy, Institute of Immunology, Federal Medical Biological Agency, 24 Kashirskoe, 115522, Moscow, Russia
| | - Andrey E. Shulzhenko
- Department of Allergology and Immunotherapy, Institute of Immunology, Federal Medical Biological Agency, 24 Kashirskoe, 115522, Moscow, Russia
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Mizeva I, Potapova E, Dremin V, Kozlov I, Dunaev A. Spatial heterogeneity of cutaneous blood flow respiratory-related oscillations quantified via laser speckle contrast imaging. PLoS One 2021; 16:e0252296. [PMID: 34043720 PMCID: PMC8158914 DOI: 10.1371/journal.pone.0252296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 01/21/2021] [Indexed: 11/18/2022] Open
Abstract
LSCI technique provides experimental data which can be considered in the context of spatial blood flow coherency. Analysis of vascular tone oscillations gives additional information to ensure a better understanding of the mechanisms affecting microvascular physiology. The oscillations with different frequencies are due to different physiological mechanisms. The reasons for the generation of peripheral blood flow oscillations in the 0.14-0.6 Hz frequency band are as follows: cardio-respiratory interactions, pressure variations in the venous part of the circulatory system, and the effect of the sympathetic nervous system on the vascular tone. Earlier, we described the spatial heterogeneity of around 0.3 Hz oscillations and this motivated us to continue the research to find the conditions for the occurrence of spatial phase synchronization. For this purpose, a number of physiological tests (controlled respiration, breath holder, and venous occlusion tests) which influence the blood flow oscillations of 0.14-0.6 Hz were considered, an appropriate measurement system and the required data processing algorithms were developed. At spontaneous respiration, the oscillations with frequencies around 0.3 Hz were stochastic, whereas all the performed tests induced an increase in spatial coherence. The protocols and methods proposed here can help to clarify whether the heterogeneity of respiratory-related blood flow oscillations exists on the skin surface.
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Affiliation(s)
- Irina Mizeva
- Institute of Continuous Media Mechanics UrB RAS, Perm, Russia
- Research & Development Center of Biomedical Photonics, Orel State University, Orel, Russia
- * E-mail:
| | - Elena Potapova
- Research & Development Center of Biomedical Photonics, Orel State University, Orel, Russia
| | - Viktor Dremin
- Research & Development Center of Biomedical Photonics, Orel State University, Orel, Russia
- College of Engineering and Physical Sciences, Aston University, Birmingham, United Kingdom
| | - Igor Kozlov
- Research & Development Center of Biomedical Photonics, Orel State University, Orel, Russia
| | - Andrey Dunaev
- Research & Development Center of Biomedical Photonics, Orel State University, Orel, Russia
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Jiang Y, Hu H, Li X, Lou J, Zhang Y, He X, Wu Y, Shao X, Fang J. Difference in Moxibustion-Induced Microcirculatory Responses between the Heart and Lung Meridians Assessed by Laser Doppler Flowmetry. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE : ECAM 2021; 2021:6644625. [PMID: 33868440 PMCID: PMC8032512 DOI: 10.1155/2021/6644625] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 01/18/2021] [Accepted: 03/20/2021] [Indexed: 12/11/2022]
Abstract
OBJECTIVE By comparing the differences in microcirculatory responses of the heart and lung meridians induced by moxibustion on these two meridians, respectively, this study aimed to investigate the specificity for site-to-site association on body surface between different meridians. METHODS Eighty healthy adults were enrolled and divided into the lung meridian intervention group and heart meridian intervention group in a ratio of 1 : 1. Three-channel laser Doppler flowmetry was used to monitor microcirculatory responses for the heart and lung meridians. Primary outcome was change of blood perfusion units (PU) of three measurement sites along the two meridians. RESULTS In the lung meridian intervention group, following moxibustion performed at LU5 of the lung meridian, PU in the distal site of the lung meridian increased significantly. By contrast, the PU of HT3 in the heart meridian, which was nearest to the moxibustion site, did not change significantly. PU in the distal site of the heart meridian declined. Meanwhile, significant difference in PU change was detected between the distal site of the lung meridian and the other two control sites of the heart meridians during moxibustion and postmoxibustion. Alternatively, similar to the results of the lung meridian intervention group, the specificity of microcirculatory response between the heart and lung meridians was observed in the heart meridian intervention group. CONCLUSIONS For the heart and lung meridians, the effect of moxibustion-induced microcirculatory response may be more related to meridian routes than the specific distance between two sites located at different meridians, thereby supporting possible specificity for site-to-site association on the body surface between these two meridians. Nevertheless, given that only two meridians and limited measurement sites were compared, all current findings are not sufficiently robust. Further research should be conducted to investigate more meridians and measurement sites.
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Affiliation(s)
- Yongliang Jiang
- Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou 310053, China
| | - Hantong Hu
- Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou 310053, China
- Department of Acupuncture and Moxibustion, The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou City, Zhejiang Province, China
| | - Xiaoyu Li
- Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou 310053, China
| | - Jiali Lou
- Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou 310053, China
| | - Yajun Zhang
- Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou 310053, China
| | - Xiaofen He
- Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou 310053, China
| | - Yuanyuan Wu
- Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou 310053, China
| | - Xiaomei Shao
- Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou 310053, China
| | - Jianqiao Fang
- Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou 310053, China
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13
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Laser Doppler Spectrum Analysis Based on Calculation of Cumulative Sums Detects Changes in Skin Capillary Blood Flow in Type 2 Diabetes Melitus. Diagnostics (Basel) 2021; 11:diagnostics11020267. [PMID: 33572387 PMCID: PMC7916189 DOI: 10.3390/diagnostics11020267] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/31/2021] [Accepted: 02/03/2021] [Indexed: 12/14/2022] Open
Abstract
In this article, we introduce a new method of signal processing and data analysis for the digital laser Doppler flowmetry. Our approach is based on the calculation of cumulative sums over the registered Doppler power spectra. The introduced new parameter represents an integral estimation for the redistribution of moving red blood cells over the range of speed. The prototype of the device implementing the technique is developed and tested in preliminary clinical trials. The methodology was verified with the involvement of two age groups of healthy volunteers and in a group of patients with type 2 diabetes mellitus. The main practical result of the study is the development of a set of binary linear classifiers that allow the method to identify typical patterns of the microcirculation for the healthy volunteers and diabetic patients based on the presented diagnostic algorithm.
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Li X, Wu L, Yang Z, Hu Y, Zhou C, Ji R. Assessment of Microcirculation in the Type 2 Diabetic and Impaired Glucose Tolerance Feet of Elderly Men by CEUS. Diabetes Metab Syndr Obes 2021; 14:3647-3652. [PMID: 34413664 PMCID: PMC8369044 DOI: 10.2147/dmso.s314727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 07/12/2021] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE To evaluate the foot microcirculation in type 2 diabetes mellitus (T2DM) and impaired glucose tolerance patients (IGT) with contrast-enhanced ultrasound (CEUS). METHODS The study included 37 patients with T2DM but without diabetic foot (DM group), 15 patients with impaired glucose tolerance (IGT group) and 10 elderly males with normal fasting blood glucose (FBS) and negative glucose tolerance tests (control group). Color Doppler flow imaging (CDFI) and CEUS were performed on the right foot great toes for detecting the blood perfusion performance. CEUS images were recorded and parameters of CDFI and flow time-intensity curves (TICs) were analyzed by the Student's t-test. RESULTS There was no significant difference in CDFI parameters pulse index and peak systolic blood flow velocity (PSV) among the three groups (P >0.05). Compared with control group, CEUS images of IGT and DM groups showed lower microvascular density and were pale. Peak intensity (PI) and area under time-intensity curve (AUC) in control, IGT and DM groups were decreased gradually (PI 46.36±10.96 vs 35.26±11.65 vs 28.15±7.94, P = 0.001, AUC 5.12±1.02 vs 3.25±1.60 vs 2.81±1.20, P = 0.001). The arrival times (AT) and time to peak (TTP) tended to be increased with the extension of DM course, but the difference was not statistically significant (AT, P = 0.260, TTP, P = 0.481). CONCLUSION CEUS, as a noninvasive and valuable technique, could detect the alterations in foot microcirculation of DM and IGT patients.
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Affiliation(s)
- Xiaoyu Li
- Department of Ultrasound, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People’s Republic of China
| | - Lin Wu
- Department of Geriatrics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People’s Republic of China
| | - Zhifang Yang
- Department of Ultrasound, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People’s Republic of China
| | - Yunyun Hu
- Department of Ultrasound, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People’s Republic of China
| | - Chun Zhou
- Department of Ultrasound, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People’s Republic of China
- Correspondence: Chun Zhou; Ri Ji Department of Ultrasound, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People’s Republic of ChinaTel/Fax +86 021 63846590; Tel +86 18717771587 Email ;
| | - Ri Ji
- Department of Ultrasound, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People’s Republic of China
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15
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Saha M, Dremin V, Rafailov I, Dunaev A, Sokolovski S, Rafailov E. Wearable Laser Doppler Flowmetry Sensor: A Feasibility Study with Smoker and Non-Smoker Volunteers. BIOSENSORS-BASEL 2020; 10:bios10120201. [PMID: 33297337 PMCID: PMC7762214 DOI: 10.3390/bios10120201] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/01/2020] [Accepted: 12/03/2020] [Indexed: 12/14/2022]
Abstract
Novel, non-invasive wearable laser Doppler flowmetry (LDF) devices measure real-time blood circulation of the left middle fingertip and the topside of the wrist of the left hand. The LDF signals are simultaneously recorded for fingertip and wrist. The amplitude of blood flow signals and wavelet analysis of the signal are used for the analysis of blood perfusion parameters. The aim of this pilot study is to validate the accuracy of blood circulation measurements recorded by one such non-invasive wearable LDF device for healthy young non-smokers and smokers. This study reveals a higher level of blood perfusion in the non-smoker group compared to the smoker group and vice-versa for the variation of pulse frequency. This result can be useful to assess the sensitivity of the wearable LDF sensor in determining the effect of nicotine for smokers as compared to non-smokers and also the blood microcirculation in smokers with different pathologies.
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Affiliation(s)
- Mou Saha
- Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET, UK; (S.S.); (E.R.)
- Correspondence: (M.S.); (V.D.)
| | - Viktor Dremin
- Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET, UK; (S.S.); (E.R.)
- Research & Development Center of Biomedical Photonics, Orel State University, 302026 Orel, Russia;
- Correspondence: (M.S.); (V.D.)
| | - Ilya Rafailov
- Aston Medical Technology Ltd., Birmingham B7 4BB, UK;
| | - Andrey Dunaev
- Research & Development Center of Biomedical Photonics, Orel State University, 302026 Orel, Russia;
| | - Sergei Sokolovski
- Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET, UK; (S.S.); (E.R.)
| | - Edik Rafailov
- Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET, UK; (S.S.); (E.R.)
- Saratov State University, 410012 Saratov, Russia
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16
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Zherebtsov E, Zajnulina M, Kandurova K, Potapova E, Dremin V, Mamoshin A, Sokolovski S, Dunaev A, Rafailov EU. Machine Learning Aided Photonic Diagnostic System for Minimally Invasive Optically Guided Surgery in the Hepatoduodenal Area. Diagnostics (Basel) 2020; 10:E873. [PMID: 33121013 PMCID: PMC7693603 DOI: 10.3390/diagnostics10110873] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 10/19/2020] [Accepted: 10/24/2020] [Indexed: 12/29/2022] Open
Abstract
Abdominal cancer is a widely prevalent group of tumours with a high level of mortality if diagnosed at a late stage. Although the cancer death rates have in general declined over the past few decades, the mortality from tumours in the hepatoduodenal area has significantly increased in recent years. The broader use of minimal access surgery (MAS) for diagnostics and treatment can significantly improve the survival rate and quality of life of patients after surgery. This work aims to develop and characterise an appropriate technical implementation for tissue endogenous fluorescence (TEF) and assess the efficiency of machine learning methods for the real-time diagnosis of tumours in the hepatoduodenal area. In this paper, we present the results of the machine learning approach applied to the optically guided MAS. We have elaborated tissue fluorescence approach with a fibre-optic probe to record the TEF and blood perfusion parameters during MAS in patients with cancers in the hepatoduodenal area. The measurements from the laser Doppler flowmetry (LDF) channel were used as a sensor of the tissue vitality to reduce variability in TEF data. Also, we evaluated how the blood perfusion oscillations are changed in the tumour tissue. The evaluated amplitudes of the cardiac (0.6-1.6 Hz) and respiratory (0.2-0.6 Hz) oscillations was significantly higher in intact tissues (p < 0.001) compared to the cancerous ones, while the myogenic (0.2-0.06 Hz) oscillation did not demonstrate any statistically significant difference. Our results demonstrate that a fibre-optic TEF probe accompanied with ML algorithms such as k-Nearest Neighbours or AdaBoost is highly promising for the real-time in situ differentiation between cancerous and healthy tissues by detecting the information about the tissue type that is encoded in the fluorescence spectrum. Also, we show that the detection can be supplemented and enhanced by parallel collection and classification of blood perfusion oscillations.
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Affiliation(s)
- Evgeny Zherebtsov
- Research and Development Center of Biomedical Photonics, Orel State University, 302026 Orel, Russia; (K.K.); (E.P.); (V.D.); (A.M.); (A.D.)
- Faculty of Information Technology and Electrical Engineering, University of Oulu, Optoelectronics and Measurement Techniques Unit, 90570 Oulu, Finland
| | - Marina Zajnulina
- Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET, UK; (M.Z.); (S.S.); (E.U.R.)
| | - Ksenia Kandurova
- Research and Development Center of Biomedical Photonics, Orel State University, 302026 Orel, Russia; (K.K.); (E.P.); (V.D.); (A.M.); (A.D.)
| | - Elena Potapova
- Research and Development Center of Biomedical Photonics, Orel State University, 302026 Orel, Russia; (K.K.); (E.P.); (V.D.); (A.M.); (A.D.)
| | - Viktor Dremin
- Research and Development Center of Biomedical Photonics, Orel State University, 302026 Orel, Russia; (K.K.); (E.P.); (V.D.); (A.M.); (A.D.)
- Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET, UK; (M.Z.); (S.S.); (E.U.R.)
| | - Andrian Mamoshin
- Research and Development Center of Biomedical Photonics, Orel State University, 302026 Orel, Russia; (K.K.); (E.P.); (V.D.); (A.M.); (A.D.)
- Department of X-ray Surgical Methods of Diagnosis and Treatment, Orel Regional Clinical Hospital, 302028 Orel, Russia
| | - Sergei Sokolovski
- Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET, UK; (M.Z.); (S.S.); (E.U.R.)
| | - Andrey Dunaev
- Research and Development Center of Biomedical Photonics, Orel State University, 302026 Orel, Russia; (K.K.); (E.P.); (V.D.); (A.M.); (A.D.)
| | - Edik U. Rafailov
- Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET, UK; (M.Z.); (S.S.); (E.U.R.)
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17
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Zharkikh E, Dremin V, Zherebtsov E, Dunaev A, Meglinski I. Biophotonics methods for functional monitoring of complications of diabetes mellitus. JOURNAL OF BIOPHOTONICS 2020; 13:e202000203. [PMID: 32654427 DOI: 10.1002/jbio.202000203] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/02/2020] [Accepted: 07/04/2020] [Indexed: 06/11/2023]
Abstract
The prevalence of diabetes complications is a significant public health problem with a considerable economic cost. Thus, the timely diagnosis of complications and prevention of their development will contribute to increasing the length and quality of patient life, and reducing the economic costs of their treatment. This article aims to review the current state-of-the-art biophotonics technologies used to identify the complications of diabetes mellitus and assess the quality of their treatment. Additionally, these technologies assess the structural and functional properties of biological tissues, and they include capillaroscopy, laser Doppler flowmetry and hyperspectral imaging, laser speckle contrast imaging, diffuse reflectance spectroscopy and imaging, fluorescence spectroscopy and imaging, optical coherence tomography, optoacoustic imaging and confocal microscopy. Recent advances in the field of optical noninvasive diagnosis suggest a wider introduction of biophotonics technologies into clinical practice and, in particular, in diabetes care units.
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Affiliation(s)
- Elena Zharkikh
- Research & Development Center of Biomedical Photonics, Orel State University, Orel, Russia
| | - Viktor Dremin
- Research & Development Center of Biomedical Photonics, Orel State University, Orel, Russia
- School of Engineering and Applied Science, Aston University, Birmingham, UK
| | - Evgeny Zherebtsov
- Research & Development Center of Biomedical Photonics, Orel State University, Orel, Russia
- Optoelectronics and Measurement Techniques unit, University of Oulu, Oulu, Finland
| | - Andrey Dunaev
- Research & Development Center of Biomedical Photonics, Orel State University, Orel, Russia
| | - Igor Meglinski
- School of Engineering and Applied Science, Aston University, Birmingham, UK
- Optoelectronics and Measurement Techniques unit, University of Oulu, Oulu, Finland
- Interdisciplinary Laboratory of Biophotonics, National Research Tomsk State University, Tomsk, Russia
- Institute of Engineering Physics for Biomedicine (PhysBio), National Research Nuclear University-MEPhI, Moscow, Russia
- School of Life and Health Sciences, Aston University, Birmingham, UK
- Department of Histology, Cytology and Embryology, Institute of Clinical Medicine N.V. Sklifosovsky, I.M. Sechenov First Moscow State Medical University, Moscow, Russia
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18
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Abdulhameed YA, McClintock PVE, Stefanovska A. Race-specific differences in the phase coherence between blood flow and oxygenation: A simultaneous NIRS, white light spectroscopy and LDF study. JOURNAL OF BIOPHOTONICS 2020; 13:e201960131. [PMID: 31944599 DOI: 10.1002/jbio.201960131] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/12/2019] [Accepted: 12/30/2019] [Indexed: 06/10/2023]
Abstract
Race-specific differences in the level of glycated hemoglobin are well known. However, these differences were detected by invasive measurement of mean oxygenation, and their understanding remains far from complete. Given that oxygen is delivered to the cells by hemoglobin through the cardiovascular system, a possible approach is to investigate the phase coherence between blood flow and oxygen transportation. Here we introduce a noninvasive optical method based on simultaneous recordings using NIRS, white light spectroscopy and LDF, combined with wavelet-based phase coherence analysis. Signals were recorded simultaneously for individuals in two groups of healthy subjects, 16 from Sub-Saharan Africa (BA group) and 16 Europeans (CA group). It was found that the power of myogenic oscillations in oxygenated and de-oxygenated hemoglobin is higher in the BA group, but that the phase coherence between blood flow and oxygen saturation, or blood flow and hemoglobin concentrations is higher in the CA group.
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Affiliation(s)
- Yunus A Abdulhameed
- Department of Physics, Lancaster University, Lancaster, UK
- Department of Physics, Yusuf Maitama Sule University, Kano, Nigeria
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Dremin V, Zherebtsov E, Bykov A, Popov A, Doronin A, Meglinski I. Influence of blood pulsation on diagnostic volume in pulse oximetry and photoplethysmography measurements. APPLIED OPTICS 2019; 58:9398-9405. [PMID: 31873531 DOI: 10.1364/ao.58.009398] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 10/25/2019] [Indexed: 05/27/2023]
Abstract
Recent advances in the development of ultra-compact semiconductor lasers and technology of printed flexible hybrid electronics have opened broad perspectives for the design of new pulse oximetry and photoplethysmography devices. Conceptual design of optical diagnostic devices requires careful selection of various technical parameters, including spectral range; polarization and intensity of incident light; actual size, geometry, and sensitivity of the detector; and mutual position of the source and detector on the surface of skin. In the current study utilizing a unified Monte Carlo computational tool, we explore the variations in diagnostic volume due to arterial blood pulsation for typical transmitted and back-scattered probing configurations in a human finger. The results of computational studies show that the variations in diagnostic volumes due to arterial pulse wave are notably (up to 45%) different in visible and near-infrared spectral ranges in both transmitted and back-scattered probing geometries. While these variations are acceptable for relative measurements in pulse oximetry and/or photoplethysmography, for absolute measurements, an alignment normalization of diagnostic volume is required and can be done by a computational approach utilized in the framework of the current study.
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