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Karlas A, Katsouli N, Fasoula NA, Bariotakis M, Chlis NK, Omar M, He H, Iakovakis D, Schäffer C, Kallmayer M, Füchtenbusch M, Ziegler A, Eckstein HH, Hadjileontiadis L, Ntziachristos V. Dermal features derived from optoacoustic tomograms via machine learning correlate microangiopathy phenotypes with diabetes stage. Nat Biomed Eng 2023; 7:1667-1682. [PMID: 38049470 PMCID: PMC10727986 DOI: 10.1038/s41551-023-01151-w] [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: 04/19/2022] [Accepted: 10/24/2023] [Indexed: 12/06/2023]
Abstract
Skin microangiopathy has been associated with diabetes. Here we show that skin-microangiopathy phenotypes in humans can be correlated with diabetes stage via morphophysiological cutaneous features extracted from raster-scan optoacoustic mesoscopy (RSOM) images of skin on the leg. We obtained 199 RSOM images from 115 participants (40 healthy and 75 with diabetes), and used machine learning to segment skin layers and microvasculature to identify clinically explainable features pertaining to different depths and scales of detail that provided the highest predictive power. Features in the dermal layer at the scale of detail of 0.1-1 mm (such as the number of junction-to-junction branches) were highly sensitive to diabetes stage. A 'microangiopathy score' compiling the 32 most-relevant features predicted the presence of diabetes with an area under the receiver operating characteristic curve of 0.84. The analysis of morphophysiological cutaneous features via RSOM may allow for the discovery of diabetes biomarkers in the skin and for the monitoring of diabetes status.
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Affiliation(s)
- Angelos Karlas
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany
- Department for Vascular and Endovascular Surgery, Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany
| | - Nikoletta Katsouli
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany
| | - Nikolina-Alexia Fasoula
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany
| | - Michail Bariotakis
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany
| | - Nikolaos-Kosmas Chlis
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany
- Institute of Computational Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Murad Omar
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany
| | - Hailong He
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany
| | - Dimitrios Iakovakis
- Department of Biomedical Engineering, Healthcare Engineering Innovation Center (HEIC), Khalifa University, Abu Dhabi, United Arab Emirates
- Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Christoph Schäffer
- Department for Vascular and Endovascular Surgery, Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany
| | - Michael Kallmayer
- Department for Vascular and Endovascular Surgery, Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany
| | | | - Annette Ziegler
- Forschergruppe Diabetes e.V., Helmholtz Zentrum München, Neuherberg, Germany
- Institute of Diabetes Research, Helmholtz Zentrum München, Neuherberg, Germany
- Forschergruppe Diabetes, Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany
| | - Hans-Henning Eckstein
- Department for Vascular and Endovascular Surgery, Klinikum rechts der Isar, Technical University of Munich (TUM), Munich, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany
| | - Leontios Hadjileontiadis
- Department of Biomedical Engineering, Healthcare Engineering Innovation Center (HEIC), Khalifa University, Abu Dhabi, United Arab Emirates
- Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Vasilis Ntziachristos
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany.
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany.
- DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany.
- Munich Institute of Robotics and Machine Intelligence (MIRMI), Technical University of Munich, Munich, Germany.
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Tikhonova IV, Grinevich AA, Tankanag AV, Safronova VG. Skin Microhemodynamics and Mechanisms of Its Regulation in Type 2 Diabetes Mellitus. Biophysics (Nagoya-shi) 2022; 67:647-659. [PMID: 36281313 PMCID: PMC9581453 DOI: 10.1134/s0006350922040200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/19/2022] [Accepted: 05/20/2022] [Indexed: 11/07/2022] Open
Abstract
The review presents modern ideas about peripheral microhemodynamics, approaches to the ana-lysis of skin blood flow oscillations and their diagnostic significance. Disorders of skin microhemodynamics in type 2 diabetes mellitus (DM) and the possibility of their interpretation from the standpoint of external and internal interactions between systems of skin blood flow regulation, based on a comparison of couplings in normal and pathological conditions, including models of pathologies on animals, are considered. The factors and mechanisms of vasomotor regulation, among them receptors and signaling events in endothelial and smooth muscle cells considered as models of microvessels are discussed. Attention was drawn to the disturbance of Ca2+-dependent regulation of coupling between vascular cells and NO-dependent regulation of vasodilation in diabetes mellitus. The main mechanisms of insulin resistance in type 2 DM are considered to be a defect in the number of insulin receptors and impaired signal transduction from the receptor to phosphatidylinositol-3-kinase and downstream targets. Reactive oxygen species plays an important role in vascular dysfunction in hyperglycemia. It is assumed that the considered molecular and cellular mechanisms of microhemodynamics regulation are involved in the formation of skin blood flow oscillations. Parameters of skin blood microcirculation can be used as diagnostic and prognostic markers for assessing the state of the body.
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Affiliation(s)
- I. V. Tikhonova
- Institute of Cell Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow oblast Russia
| | - A. A. Grinevich
- Institute of Cell Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow oblast Russia
| | - A. V. Tankanag
- Institute of Cell Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow oblast Russia
| | - V. G. Safronova
- Institute of Cell Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow oblast Russia
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Liu S, Zhao L, Liu Y. The Origin of Vasomotion and Stochastic Resonance in Vasomotion. Front Bioeng Biotechnol 2022; 10:819716. [PMID: 35309989 PMCID: PMC8924506 DOI: 10.3389/fbioe.2022.819716] [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: 11/22/2021] [Accepted: 01/14/2022] [Indexed: 11/13/2022] Open
Abstract
Vasomotion is the spontaneous time-dependent contraction and relaxation of micro arteries and the oscillating frequency is about 0.01–0.1 Hz. The physiological mechanism of vasomotion has not been thoroughly understood. From the dynamics point of view, the heartbeat is the only external loading exerted on the vascular system. We speculate that the nonlinear vascular system and the variable period of the heartbeat might induce the low-frequency vasomotion. In this study, the laser Doppler flowmeter is used to measure the time series of radial artery blood flow and reconstructed modified time series that has the same period as the measured time series but different heartbeat curves. We measured the time series of radial artery blood flow in different conditions by adding different noise disturbances on the forearm, and we decomposed the experiment pulse signal by Hilbert–Huang transform. The wavelet spectral analyses showed that the low-frequency components were induced by the variable period but independent of the shape of the heartbeat curve. Furthermore, we simulated the linear flow in a single pipe and the nonlinear flow in a piping network and found that the nonlinear flow would generate low-frequency components. From the results, we could deduce that the variable period of heartbeat and the nonlinearity of the vascular system induce vasomotion. The noise has effects on the blood signals related to the respiratory activities (∼0.3 Hz) but little influence on that related to the cardiac activities (∼1 Hz). Adding white noise and then stopping would induce an SNR increase in the frequency band related to vasomotion (∼0.1 Hz).
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Affiliation(s)
- Shuhong Liu
- Research Centre for Fluid-Structure Interactions, Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong SAR, China
| | - Liangjing Zhao
- Research Centre for Fluid-Structure Interactions, Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong SAR, China
| | - Yang Liu
- Department of Mechanical Engineering, Kowloon, Hong Kong SAR, China
- *Correspondence: Yang Liu,
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Rizzoni D, Mengozzi A, Masi S, Agabiti Rosei C, De Ciuceis C, Virdis A. New Noninvasive Methods to Evaluate Microvascular Structure and Function. Hypertension 2022; 79:874-886. [PMID: 35114816 DOI: 10.1161/hypertensionaha.121.17954] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The structural and functional alterations of microvessels are detected because of physiological aging and in several cardiometabolic diseases, including hypertension, diabetes, and obesity. The small resistance arteries of these patients show an increase in the media or total wall thickness to internal lumen diameter ratio (MLR or WLR), often accompanied by endothelial dysfunction. For decades, micromyography has been considered as a gold standard method for evaluating microvascular structural alterations through the measurement of MLR or WLR of subcutaneous small vessels dissected from tissue biopsies. Micromyography is the most common and reliable method for assessing microcirculatory endothelial function ex vivo, while strain-gauge venous plethysmography is considered the reference technique for in vivo studies. Recently, several noninvasive methods have been proposed to extend the microvasculature evaluation to a broader range of patients and clinical settings. Scanning laser Doppler flowmetry and adaptive optics are increasingly used to estimate the WLR of retinal arterioles. Microvascular endothelial function may be evaluated in the retina by flicker light stimulus, in the finger by tonometric approaches, or in the cutaneous or sublingual tissues by laser Doppler flowmetry or intravital microscopy. The main limitation of these techniques is the lack of robust evidence on their prognostic value, which currently reduces their widespread use in daily clinical practice. Ongoing and future studies will overcome this issue, hopefully moving the noninvasive assessment of the microvascular function and structure from bench to bedside.
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Affiliation(s)
- Damiano Rizzoni
- Clinica Medica, Department of Clinical and Experimental Sciences, University of Brescia, Italy (D.R., C.A., C.D.C.).,Division of Medicine, Spedali Civili di Brescia, Montichiari (Brescia), Italy (D.R.)
| | - Alessandro Mengozzi
- Department of Clinical and Experimental Medicine, University of Pisa, Italy (A.M., S.M., A.V.).,Institute of Life Science, Sant'Anna School of Advanced Studies, Pisa, Italy (A.M.)
| | - Stefano Masi
- Department of Clinical and Experimental Medicine, University of Pisa, Italy (A.M., S.M., A.V.).,Institute of Cardiovascular Science, University College London, United Kingdom (S.M.)
| | - Claudia Agabiti Rosei
- Clinica Medica, Department of Clinical and Experimental Sciences, University of Brescia, Italy (D.R., C.A., C.D.C.)
| | - Carolina De Ciuceis
- Clinica Medica, Department of Clinical and Experimental Sciences, University of Brescia, Italy (D.R., C.A., C.D.C.)
| | - Agostino Virdis
- Department of Clinical and Experimental Medicine, University of Pisa, Italy (A.M., S.M., A.V.)
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Diagnostic capabilities of different methods of laser doppler flowmetry spectral indexes assessment in patients with diabetic microangiopathy. BIOMEDICAL PHOTONICS 2021. [DOI: 10.24931/2413-9432-2021-10-2-18-24] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The article contains the results of a study of two different methods for calculating the spectral parameters of laser Doppler flowmetry in patients with diabetic microangiopathy caused by type 2 diabetes mellitus (main group) and those with excluded diabetes mellitus (control group). Spectral indices were calculated using either average or maximum amplitudes of the frequency ranges. When comparing the contribution of respiratory and pulse fluxmotions using average amplitudes, there were significant (p < 0.05) differences between the main and control groups. On the contrary, when using the maximum amplitudes, no significant differences were noted (p > 0.05). Also, significant correlations were found between the contributions of respiratory and pulse fluxmotions and the estimated glomerular filtration rate in the main group, using both calculation methods. These studies indicate the feasibility of using a technique based on the analysis of average amplitudes to increase the specificity of laser Doppler flowmetry as a method for diagnosing diabetic microangiopathy.
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Glazkova PA, Kulikov DA, Glazkov AA, Terpigorev SA, Rogatkin DA, Shekhyan GG, Krasulina KA, Kulikov AV, Makmatov-Rys MB, Paleev FN. Reactivity of skin microcirculation as a biomarker of cardiovascular events. Pilot study. Clin Hemorheol Microcirc 2021; 78:247-257. [PMID: 33682698 DOI: 10.3233/ch-201016] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The role of microcirculatory disorders is progressively being accepted in the pathogenesis of cardiovascular diseases. OBJECTIVE The purpose of current study is to assess whether we can consider skin microcirculation disorders as a biomarker of cardiovascular events. METHODS Group 1 consisted of healthy volunteers (n = 31); group 2 (n = 42) consisted of patients with diseases that increase the risk of cardiovascular events; group 3 (n = 39) included patients with the history of cardiovascular events. Skin microcirculation measurement was performed using laser Doppler flowmetry during the heating test. RESULTS LDF parameters reflecting the rapid response of microcirculation to heating ("Slope 120 s" and "Slope 180 s") significantly differed in three groups (p < 0.05). A decrease in the "Slope 180 s" parameter less than 0.5 PU/s is associated with cardiovascular events (sensitivity 69.2%, specificity 66.7%; the area under the ROC curve, 0.667; 95% confidence interval [CI], 0.545-0.788, p = 0.01). Multivariable logistic regression analysis revealed that "Slope 180 s≤0.5 PU/s" was significantly related to cardiovascular events (adjusted odds ratio = 3.9, p = 0.019, CI 95% 1.2-12). CONCLUSIONS Reduced reactivity of the skin microcirculation may be useful as a biomarker of severe damage to the cardiovascular system and is promising as a risk factor for cardiovascular events.
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Affiliation(s)
- P A Glazkova
- Moscow Regional Research and Clinical Institute ("MONIKI"), Moscow, Russian Federation
| | - D A Kulikov
- Moscow Regional Research and Clinical Institute ("MONIKI"), Moscow, Russian Federation.,Moscow Region State University, Mytishchi, Russian Federation
| | - A A Glazkov
- Moscow Regional Research and Clinical Institute ("MONIKI"), Moscow, Russian Federation
| | - S A Terpigorev
- Moscow Regional Research and Clinical Institute ("MONIKI"), Moscow, Russian Federation
| | - D A Rogatkin
- Moscow Regional Research and Clinical Institute ("MONIKI"), Moscow, Russian Federation
| | - G G Shekhyan
- Moscow Regional Research and Clinical Institute ("MONIKI"), Moscow, Russian Federation
| | - K A Krasulina
- Moscow Regional Research and Clinical Institute ("MONIKI"), Moscow, Russian Federation
| | - A V Kulikov
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Russian Federation
| | - M B Makmatov-Rys
- Moscow Regional Research and Clinical Institute ("MONIKI"), Moscow, Russian Federation
| | - F N Paleev
- National medical research center of cardiology of the Ministry of healthcare of the Russian Federation, Moscow, Russian Federation
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Finžgar M, Frangež HB, Cankar K, Frangež I. Transcutaneous application of the gaseous CO 2 for improvement of the microvascular function in patients with diabetic foot ulcers. Microvasc Res 2020; 133:104100. [PMID: 33181169 DOI: 10.1016/j.mvr.2020.104100] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/03/2020] [Accepted: 11/03/2020] [Indexed: 01/13/2023]
Abstract
INTRODUCTION Microvascular function is impaired in patients with diabetes mellitus (DM) and is involved in numerous DM complications. Several microvascular-supporting interventions have been proposed of which the transcutaneous application of gaseous CO2 (hereinafter CO2 therapy) is one of the most promising. The aim of present study was to determine the effect of repeated CO2 therapies on the cutaneous microvascular function in DM patients with diabetic foot ulcers. METHODOLOGY A total of 42 subjects with at least one chronic diabetic foot ulcer were enrolled in the study. They were divided into the experimental group (21 subjects aged 64.6 ± 11.6 years) that underwent 4-week-long treatment with transcutaneous application of gaseous CO2 (hereinafter CO2 therapies), and the placebo group (21 subjects aged 65.0 ± 10.7 years) that underwent 4-week-long placebo treatment with transcutaneous application of air. Before the first and after the last treatment in both groups, laser Doppler (LD) flux in foot cutaneous microcirculation, heart rate, and arterial blood pressure measurements were carried out during rest and local thermal hyperaemia (LTH) provocation test. RESULTS In the experimental group the following statistically significant changes were observed after the completed treatment 1) increased mean relative powers of LD flux signals during rest in the frequency bands related to NO-independent endothelial (0.07 ± 0.055 vs. 0.048 ± 0.059, p = 0.0058), NO-mediated endothelial (0.154 ± 0.101 vs. 0.113 ± 0.108, p = 0.015), and neurogenic (0.17 ± 0.107 vs. 0.136 ± 0.098, p = 0.018) activity; 2) decreased resting LD flux (35 ± 29 PU vs. 52 ± 56 PU; p = 0.038); and 3) increased peak LD flux as a function of baseline during LTH (482 ± 474%BL vs. 287 ± 262%BL, p = 0.036); there were no statistically significant changes observed in the placebo group. No systemic effects were observed in none of the two groups by means of mean values of heart rate and arterial blood pressure. CONCLUSIONS Repeated CO2 therapies improves the microvasular function in DM patients without any systemic side effects.
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Affiliation(s)
- Miha Finžgar
- Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva c. 6, Ljubljana, Slovenia
| | - Helena Ban Frangež
- Department of Obstetrics and Gynaecology, University Medical Centre Ljubljana, Šlajmerjeva ul. 3, 1000 Ljubljana, Slovenia; Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia
| | - Ksenija Cankar
- Institute of Physiology, Faculty of Medicine, University of Ljubljana, Zaloška c. 4, 1000 Ljubljana, Slovenia
| | - Igor Frangež
- Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia; Department of Surgical Infections, University Medical Centre Ljubljana, Zaloška c. 2, 1000 Ljubljana, Slovenia.
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A new approach to the analysis of skin blood flow oscillations in human. Microvasc Res 2019; 126:103889. [PMID: 31255697 DOI: 10.1016/j.mvr.2019.103889] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 05/21/2019] [Accepted: 06/26/2019] [Indexed: 12/27/2022]
Abstract
It is considered that there are six non-overlapping frequency intervals with constant boundaries. These intervals correspond to different mechanisms of skin blood flow regulation. The boundaries do not depend on functional conditions but this statement should be verified. Also it remains unclear how the oscillatory components of skin blood flow are related. Thus the study is aimed to verify statistically the boundaries of frequency intervals, to test the hypothesis that the boundaries depend on age and to search for relationships between spectral components of skin blood flow. The study involved 105 healthy volunteers aged from 20 to 65 years, which were divided into two age groups. Skin blood flow was registered with laser Doppler flowmeter (LDF). Assessments of frequency interval boundaries and relationship between the frequency oscillatory components of blood flow were conducted with histogram approach, bootstrap method and correlation analysis. New frequency interval boundaries were found. They were different in two groups. A linear correlation and frequency areas with moderate (0.5-0.7) and high (>0.7) correlation coefficients were found between spectral components of blood flow. The dependence of these correlations on the age was shown. Thus we proposed a conceptually new approach to analysis of spectral components of skin microhemodynamics and interpretation of results obtained by laser Doppler techniques. This approach is the result of the development of modern understanding of relationships between skin blood flow regulation mechanisms and spectral components of LDF signals. It allows one to have a new look at these relationships as well as demonstrates their dependence on the functional state of the organism as a whole.
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Stepanov R, Podtaev S, Tsiberkin K. Sample size determination in the laser-Doppler measurements of skin blood flow. Microvasc Res 2019; 125:103883. [PMID: 31103448 DOI: 10.1016/j.mvr.2019.103883] [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: 01/10/2019] [Revised: 05/08/2019] [Accepted: 05/11/2019] [Indexed: 10/26/2022]
Abstract
Pre-study calculations of the required sample size are vital to a large majority of studies. Using the method based on the Monte-Carlo simulations, we have illustrated how the sample size is related to the statistic power value, the significance level, the variability of observations and the minor magnitude of the effect of interest under study. If the study has been already completed, one should not perform any 'post hoc' power calculations. In this case, calculation of confidence intervals is a better choice. We assessed the confidence intervals given in a number of publications where microcirculation is studied by LDF techniques using different protocols. We have found that types I and II errors are frequently encountered in the LDF studies, which is a consequence of an inappropriate sample size.
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Affiliation(s)
- Rodion Stepanov
- Institute of Continuous Media Mechanics, Korolyov str. 1, 614013 Perm, Russia; Perm National Research Polytechnic University, Komsomolskii av. 29, 614990 Perm, Russia.
| | - Sergey Podtaev
- Institute of Continuous Media Mechanics, Korolyov str. 1, 614013 Perm, Russia
| | - Kirill Tsiberkin
- Department of Physics, Perm State University, Bukirev str. 15, Perm 614990, Russia
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Chipperfield AJ, Thanaj M, Scorletti E, Byrne CD, Clough GF. Multi-domain analysis of microvascular flow motion dynamics in NAFLD. Microcirculation 2019; 26:e12538. [PMID: 30803094 DOI: 10.1111/micc.12538] [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: 11/22/2018] [Revised: 01/22/2019] [Accepted: 02/20/2019] [Indexed: 12/21/2022]
Abstract
OBJECTIVE To determine whether analysis of microvascular network perfusion using complexity-based methods can discriminate between groups of individuals at an increased risk of developing CVD. METHODS Data were obtained from laser Doppler recordings of skin blood flux at the forearm in 50 participants with non-alcoholic fatty liver disease grouped for absence (n = 28) or presence (n = 14) of type 2 diabetes and use of calcium channel blocker medication (n = 8). Power spectral density was evaluated and Lempel-Ziv complexity determined to quantify signal information content at single and multiple time-scales to account for the different processes modulating network perfusion. RESULTS Complexity was associated with dilatory capacity and respiration and negatively with baseline blood flux and cardiac band power. The relationship between the modulators of flowmotion and complexity of blood flux is shown to change with time-scale improving discrimination between groups. Multiscale Lempel-Ziv achieved best classification accuracy of 86.1%. CONCLUSIONS Time and frequency domain measures alone are insufficient to discriminate between groups. As cardiovascular disease risk increases, the degree of complexity of the blood flux signal reduces, indicative of a reduced temporal activity and heterogeneous distribution of blood flow within the microvascular network sampled. Complexity-based methods, particularly multiscale variants, are shown to have good discriminatory capabilities.
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Affiliation(s)
- Andrew J Chipperfield
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
| | - Marjola Thanaj
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
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Chen CT, Hsu CH, Liu JR, Wu HB, Chou YS, Hsiu H. Comparison of complexity and spectral indices of skin-surface laser-doppler signals in patients with breast cancer receiving chemotherapy and Kuan-Sin-Yin. Clin Hemorheol Microcirc 2019; 73:553-563. [PMID: 31156144 DOI: 10.3233/ch-190569] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This study tested the hypothesis that measuring and analyzing skin-surface blood flow dynamics can be used to noninvasively discriminate the different microcirculatory and physiological function states of breast-cancer patients with chemotherapy between receiving and not receiving Kuan-Sin-Yin (KSY) treatment. The 17 included patients were assigned randomly to 2 comparison groups: Group K (n = 10) received KSY treatment, while Group NK (n = 7) did not receive KSY treatment. Beat-to-beat, spectral, and approximate-entropy (ApEn) analyses were applied to the 20-minute laser-Doppler sequences. The self-reported quality of life and cancer-related symptoms of patients were also investigated. In posttests, Group NK had a significantly larger ApEn ratio than that in Group K, significantly smaller values of laser-Doppler-flowmetry variability indices, and a slightly higher relative energy contribution of the neural-related frequency band compared to those in the pretests. Almost all cancer-related symptoms showed improvements in Group K compared to in Group NK. The present findings indicated that the present analysis can be used to detect the significantly different responses in the laser-Doppler indices between taking and not taking KSY. The KSY effect was also noted to be accompanied with improvement of EORTC QLQ-C30 scores. These could lead to a rapid, inexpensive, and objective technique for enhancing clinical applications in quality-of-life monitoring of breast cancer therapy.
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Affiliation(s)
- Chao-Tsung Chen
- Institute of Traditional Medicine, National Yang-Ming University, Taipei, Taiwan
- Department of Traditional Chinese Medicine, Taipei City Hospital RenAi Branch, Taipei, Taiwan
- General Education Center, University of Taipei, Taipei, Taiwan
| | - Chung-Hua Hsu
- Institute of Traditional Medicine, National Yang-Ming University, Taipei, Taiwan
- Branch of Linsen and Chinese Medicine, Taipei City Hospital, Taipei, Taiwan
| | - Jyh-Rou Liu
- Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan
| | - Hung-Bo Wu
- Division of Hematology and Oncology, Department of Medicine, Taipei City Hospital, Renai Branch, Taipei, Taiwan
| | - Yi-Sheng Chou
- Division of Hematology and Oncology, Department of Medicine, Taipei City Hospital, Renai Branch, Taipei, Taiwan
| | - Hsin Hsiu
- Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan
- Biomedical Engineering Research Center, National Defense Medical Center, Taipei, Taiwan
- Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei, Taiwan
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