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D'iakonova EN, Fedin AI, Makerova VV, Gorbunov VN. [The use of L-lysine aescinat in the treatment of microcirculatory disturbances in patients young and middle age with violation of the intracranial venous outflow]. Zh Nevrol Psikhiatr Im S S Korsakova 2016; 116:42-50. [PMID: 27735898 DOI: 10.17116/jnevro20161169142-50] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
AIM To study the efficacy of L-lysine aescinat in the treatment of vascular and microvascular disorders in patients with cerebral venous dystonia. MATERIAL AND METHODS Sixty-eight patients, 25 male and 43 female, aged from 25 to 56 years, with disturbances of venous cerebral blood circulation and venous outflow difficulties were examined. The examination included the assessment of cerebral hemodynamics using the algorithm of complex ultrasound examinations and functional status of the microcirculation by the laser Doppler flowmetry (LDF) at baseline and 10 days after treatment with L-lysine aescinat. RESULTS AND CONCLUSION L-lysine aescinat improves intracranial venous outflow, significantly improves the functioning of microcirculation, while not affecting the normal type of microcirculation or changing it in the direction of improvement of hemodynamic parameters, has a modulating effect on the autonomic response, and can be recommended in the complex treatment of young and middle aged patients with disturbances of cerebral venous blood circulation with the predominance of vagotonia as well as hypersympathicotonia.
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Affiliation(s)
| | - A I Fedin
- National Research Medical University, Moscow, Russia Co 'Arterium', Moscow, Russia
| | | | - V N Gorbunov
- National Research Medical University, Moscow, Russia Co 'Arterium', Moscow, Russia
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Bi R, Dong J, Poh CL, Lee K. Optical methods for blood perfusion measurement--theoretical comparison among four different modalities. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2015; 32:860-6. [PMID: 26366910 DOI: 10.1364/josaa.32.000860] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Blood perfusion in human tissue can be measured in vivo by means of various optical methods, which seem to be very different from one another. The most prominent examples of them are laser Doppler flowmetry, laser speckle contrast imaging, diffuse correlation spectroscopy, and the most recently developed diffuse speckle contrast analysis. In this paper, we claim that these four seemingly different modalities are examining different aspects of the same entity-the temporal autocorrelation function of scattered photons. We will show how the observables in each modality can be theoretically derived from the temporal autocorrelation function, and will discuss the merits and drawbacks of each modality in its practical use.
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Binzoni T, Martelli F. Influence of light source-detector spacing on shape of probability density functions of scattering angles in laser Doppler flowmetry. APPLIED OPTICS 2014; 53:4580-4584. [PMID: 25090080 DOI: 10.1364/ao.53.004580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 06/03/2014] [Indexed: 06/03/2023]
Abstract
Analytical models, describing laser Doppler flowmetry and its derived applications, are based on fundamental assumptions of photon scattering angles. It is shown by means of Monte Carlo simulations that, even in the case these assumptions are correct, the presence of a specific source-detector configuration may bias the shape of the probability density functions describing scattering angle behavior. It is found that these biased shapes are generated by selective filtering of photons induced by a particular source-detector configuration. In some specific cases, this phenomenon might invalidate laser Doppler analytical models.
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Sunar U. Monitoring photodynamic therapy of head and neck malignancies with optical spectroscopies. World J Clin Cases 2013; 1:96-105. [PMID: 24303476 PMCID: PMC3845916 DOI: 10.12998/wjcc.v1.i3.96] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 04/02/2013] [Accepted: 05/08/2013] [Indexed: 02/05/2023] Open
Abstract
In recent years there has been significant developments in photosensitizers (PSs), light sources and light delivery systems that have allowed decreasing the treatment time and skin phototoxicity resulting in more frequent use of photodynamic therapy (PDT) in the clinical settings. Compared to standard treatment approaches such as chemo-radiation and surgery, PDT has much reduced morbidity for head and neck malignancies and is becoming an alternative treatment option. It can be used as an adjunct therapy to other treatment modalities without any additive cumulative side effects. Surface illumination can be an option for pre-malignant and early-stage malignancies while interstitial treatment is for debulking of thick tumors in the head and neck region. PDT can achieve equivalent or greater efficacy in treating head and neck malignancies, suggesting that it may be considered as a first line therapy in the future. Despite progressive development, clinical PDT needs improvement in several topics for wider acceptance including standardization of protocols that involve the same administrated light and PS doses and establishing quantitative tools for PDT dosimetry planning and response monitoring. Quantitative measures such as optical parameters, PS concentration, tissue oxygenation and blood flow are essential for accurate PDT dosimetry as well as PDT response monitoring and assessing therapy outcome. Unlike conventional imaging modalities like magnetic resonance imaging, novel optical imaging techniques can quantify PDT-related parameters without any contrast agent administration and enable real-time assessment during PDT for providing fast feedback to clinicians. Ongoing developments in optical imaging offer the promise of optimization of PDT protocols with improved outcomes.
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Belau M, Ninck M, Hering G, Spinelli L, Contini D, Torricelli A, Gisler T. Noninvasive observation of skeletal muscle contraction using near-infrared time-resolved reflectance and diffusing-wave spectroscopy. JOURNAL OF BIOMEDICAL OPTICS 2010; 15:057007. [PMID: 21054123 DOI: 10.1117/1.3503398] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
We introduce a method for noninvasively measuring muscle contraction in vivo, based on near-infrared diffusing-wave spectroscopy (DWS). The method exploits the information about time-dependent shear motions within the contracting muscle that are contained in the temporal autocorrelation function g(1)(τ,t) of the multiply scattered light field measured as a function of lag time, τ, and time after stimulus, t. The analysis of g(1)(τ,t) measured on the human M. biceps brachii during repetitive electrical stimulation, using optical properties measured with time-resolved reflectance spectroscopy, shows that the tissue dynamics giving rise to the speckle fluctuations can be described by a combination of diffusion and shearing. The evolution of the tissue Cauchy strain e(t) shows a strong correlation with the force, indicating that a significant part of the shear observed with DWS is due to muscle contraction. The evolution of the DWS decay time shows quantitative differences between the M. biceps brachii and the M. gastrocnemius, suggesting that DWS allows to discriminate contraction of fast- and slow-twitch muscle fibers.
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Affiliation(s)
- Markus Belau
- Universität Konstanz, Fachbereich Physik, 78457 Konstanz, Germany
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Binzoni T, Seelamantula CS, Van De Ville D. A fast time-domain algorithm for the assessment of tissue blood flow in laser-Doppler flowmetry. Phys Med Biol 2010; 55:N383-94. [PMID: 20530854 DOI: 10.1088/0031-9155/55/13/n02] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In this study, we derive a fast, novel time-domain algorithm to compute the nth-order moment of the power spectral density of the photoelectric current as measured in laser-Doppler flowmetry (LDF). It is well established that in the LDF literature these moments are closely related to fundamental physiological parameters, i.e. concentration of moving erythrocytes and blood flow. In particular, we take advantage of the link between moments in the Fourier domain and fractional derivatives in the temporal domain. Using Parseval's theorem, we establish an exact analytical equivalence between the time-domain expression and the conventional frequency-domain counterpart. Moreover, we demonstrate the appropriateness of estimating the zeroth-, first- and second-order moments using Monte Carlo simulations. Finally, we briefly discuss the feasibility of implementing the proposed algorithm in hardware.
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Affiliation(s)
- Tiziano Binzoni
- Département des Neurosciences Fondamentales, University of Geneva, and Département de l'Imagerie et des Sciences de l'Information Médicale, University Hospital, Geneva, Switzerland.
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Sunar U, Rohrbach D, Rigual N, Tracy E, Keymel K, Cooper MT, Baumann H, Henderson BH. Monitoring photobleaching and hemodynamic responses to HPPH-mediated photodynamic therapy of head and neck cancer: a case report. OPTICS EXPRESS 2010; 18:14969-78. [PMID: 20639983 PMCID: PMC2964147 DOI: 10.1364/oe.18.014969] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
We present initial results obtained during the course of a Phase I clinical trial of 2-1[hexyloxyethyl]-2-devinylpyropheophorbide-a (HPPH)-mediated photo-dynamic therapy (PDT) in a head and neck cancer patient. We quantified blood flow, oxygenation and HPPH drug photobleaching before and after therapeutic light treatment by utilizing fast, non-invasive diffuse optical methods. Our results showed that HPPH-PDT induced significant drug photobleaching, and reduction in blood flow and oxygenation suggesting significant vascular and cellular reaction. These changes were accompanied by cross-linking of the signal transducer and activator of transcription 3 (STAT3), a molecular measure for the oxidative photoreaction. These preliminary results suggest diffuse optical spectroscopies permit non-invasive monitoring of PDT in clinical settings of head and neck cancer patients.
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Affiliation(s)
- Ulas Sunar
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY, 14263, USA.
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Binzoni T, Leung TS, Van De Ville D. The photo-electric current in laser-Doppler flowmetry by Monte Carlo simulations. Phys Med Biol 2009; 54:N303-18. [DOI: 10.1088/0031-9155/54/14/n03] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Binzoni T, Van De Ville D. Full-field laser-Doppler imaging and its physiological significance for tissue blood perfusion. Phys Med Biol 2008; 53:6673-94. [PMID: 18997268 DOI: 10.1088/0031-9155/53/23/003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Using Monte Carlo simulations for a semi-infinite medium representing a skeletal muscle tissue, it is demonstrated that the zero- and first-order moments of the power spectrum for a representative pixel of a full-field laser-Doppler imager behave differently from classical laser-Doppler flowmetry. In particular, the zero-order moment has a very low sensitivity to tissue blood volume changes, and it becomes completely insensitive if the probability for a photon to interact with a moving red blood cell is above 0.05. It is shown that the loss in sensitivity is due to the strong forward scatter of the propagating photons in biological tissues (i.e., anisotropy factor g = 0.9). The first-order moment is linearly related to the root mean square of the red blood cell velocity (the Brownian component), and there is also a positive relationship with tissue blood volume. The most common physiological interpretation of the first-order moment is as tissue blood volume times expectation of the blood velocity (in probabilistic terms). In this sense, the use of the first-order moment appears to be a reasonable approach for qualitative real-time blood flow monitoring, but it does not allow us to obtain information on blood velocity or volume independently. Finally, it is shown that the spatial and temporal resolution trade-off imposed by the CMOS detectors, used in full-field laser-Doppler hardware, may lead to measurements that vary oppositely with the underlying physiological quantities. Further improvements on detectors' sampling rate will overcome this limitation.
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Affiliation(s)
- T Binzoni
- Département des Neurosciences Fondamentales, University of Geneva, Switzerland.
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Pfeiffer N, Chapman GH. Successive order, multiple scattering of two-term Henyey-Greenstein phase functions. OPTICS EXPRESS 2008; 16:13637-13642. [PMID: 18772974 DOI: 10.1364/oe.16.013637] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
An analytic solution to the problem of determining photon direction after successive scatterings in an infinite, homogeneous, isotropic medium, where each scattering event is in accordance with a two-term Henyey-Greenstein phase function, is presented and compared against Monte Carlo simulation results. The photon direction is described by a probability density function of the dot product of the initial direction and the direction after multiple scattering events, and it is found that such a probability density function can be represented as a weighted series of one-term Henyey-Greenstein phase functions.
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Affiliation(s)
- Nick Pfeiffer
- Simon Fraser University, School of Engineering Science, Burnaby, BC, Canada.
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Humeau A, Trzepizur W, Rousseau D, Chapeau-Blondeau F, Abraham P. Fisher information and Shannon entropy for on-line detection of transient signal high-values in laser Doppler flowmetry signals of healthy subjects. Phys Med Biol 2008; 53:5061-76. [DOI: 10.1088/0031-9155/53/18/014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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12
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Johnson PM, Faez S, Lagendijk A. Full characterization of anisotropic diffuse light. OPTICS EXPRESS 2008; 16:7435-7446. [PMID: 18545448 DOI: 10.1364/oe.16.007435] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We demonstrate a method for fully characterizing diffuse transport of light in a statistically anisotropic opaque material. Our technique provides a simple means of determining all parameters governing anisotropic diffusion. Anisotropy in the diffusion constant, the mean free path, and the extrapolation length are, for the first time, determined independently. These results show that the anisotropic diffusion model is effective for modeling transport in anisotropic samples, providing that the light is allowed to travel several times the transport mean free path from the source.
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Affiliation(s)
- P M Johnson
- FOM Institute for Atomic and Molecular Physics AMOLF, Kruislaan 407 Amsterdam, The Netherlands.
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Sunar U, Quon H, Durduran T, Zhang J, Du J, Zhou C, Yu G, Choe R, Kilger A, Lustig R, Loevner L, Nioka S, Chance B, Yodh AG. Noninvasive diffuse optical measurement of blood flow and blood oxygenation for monitoring radiation therapy in patients with head and neck tumors: a pilot study. JOURNAL OF BIOMEDICAL OPTICS 2006; 11:064021. [PMID: 17212544 DOI: 10.1117/1.2397548] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
This pilot study explores the potential of noninvasive diffuse correlation spectroscopy (DCS) and diffuse reflectance spectroscopy (DRS) for monitoring early relative blood flow (rBF), tissue oxygen saturation (StO(2)), and total hemoglobin concentration (THC) responses to chemo-radiation therapy in patients with head and neck tumors. rBF, StO(2), and THC in superficial neck tumor nodes of eight patients are measured before and during the chemo-radiation therapy period. The weekly rBF, StO(2), and THC kinetics exhibit different patterns for different individuals, including significant early blood flow changes during the first two weeks. Averaged blood flow increases (52.7+/-9.7)% in the first week and decreases (42.4+/-7.0)% in the second week. Averaged StO(2) increases from (62.9+/-3.4)% baseline value to (70.4+/-3.2)% at the end of the second week, and averaged THC exhibits a continuous decrease from pretreatment value of (80.7+/-7.0) [microM] to (73.3+/-8.3) [microM] at the end of the second week and to (63.0+/-8.1) [microM] at the end of the fourth week of therapy. These preliminary results suggest daily diffuse-optics-based therapy monitoring is feasible during the first two weeks and may have clinical promise.
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Affiliation(s)
- Ulas Sunar
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6396, USA.
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