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Dynamic Focusing in Ultrasound Tomography
Kratochvíla, Jiří ; Roleček, Jiří (referee) ; Jiřík, Radovan (advisor)
The aim of the master’s thesis, is to get acquainted with the dynamic focusing in conventional ultrasound systems, to modify this method for ultrasound computer tomography and to realize and interpret this modification on simulated and real data in a transparent graphic interface. The modification of the dynamic focusing was executed for the 3D ultrasound computer tomograph developed in Karlsruhe. Simulated data, that are necessary for focusing, were generated by existing program, which was adjusted. The new created program of the dynamic focusing was tested and evaluated with those simulated and real data.
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Measurement of cardiovascular parameters
Kratochvíla, Jiří ; Čmiel, Vratislav (referee) ; Kolářová, Jana (advisor)
The aim of the bachelor’s thesis is to get acquainted with the measurement of cardiovascular parameters, to realize the measurment of these parameters, to analyze them, show the statistic procedure of verifying hypotheses in this spere and finally the presentation of measured data including automatical detection of the heart rate from ECG signal in created program in Guide of Matlab system. On the basis of the theory was done the measurment on own suggestion with the Biopac system and with the quicksilver tonomether. The parameters, that were measured on the group of five people: ECG, blood pressure and the pulse frequency before and after the load. After the data processing was done the statistic analysis, the aim of this analysis was to show the procedure of verifying hypothesis, if and how are these measured parameters of cardiovascular system changing. After that the measured data were transported into Matlab system. The presentation of measured data (created program) contains the time domain and spectral analyses (using Fourier transform) of ECG signal, automatical detection of the heart rate from ECG signal, analysis of the heart rate variability (HRV) – tachogram together with detailed analysis of HRV spectra (spectra of heart rate variability – relating with parasympathetic and sympathetic activity), that are using in clinical practice too, just as the other measured parametres of the cardiovascular system.
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Analysis of measured parameters of the cardiovascular system
Lysoň, Jakub ; Vítek, Martin (referee) ; Kratochvíla, Jiří (advisor)
This bachelor thesis talks about the measurement of heart electrical activity by twelve lead ECG. The diagnostic system Biopac is used for measurement, featured by the computer program Acqknowledge. The own authentic method is designed to detect effect of load on increasing in blood pressure and heartbeat. Using a statistical procedure for testing hypotheses in this area the measurement results will be evaluated. For the analysis of measured data in time and frequency domain was used program Matlab, in which the measured results were imported. It was created functions that are implemented in an medium of Guide to the graphic design program.
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Modeling and Signal Processing in Dynamic Contrast Enhanced Magnetic Resonance Imaging
Kratochvíla, Jiří ; Šroubek,, Filip (referee) ; Tintěra,, Jaroslav (referee) ; Jiřík, Radovan (advisor)
The theoretical part of this work describes perfusion analysis of dynamic contrast enhanced magnetic resonance imaging from data acquisition to estimation of perfusion parameters. The main application fields are oncology, cardiology and neurology. The thesis is focused on quantitative perfusion analysis, specifically it contributes to solving of the the main challenge of this method – correct estimation of the contrast-agent concentration sequence in the arterial input of the region of interest (arterial input function). The goals of the thesis are stated based on literature review and on the expertise of our group. Blind deconvolution is selected as the method of choice. In the practical part of this thesis, a new method for arterial input function identification based on blind deconvolution is proposed. The method is designed for both preclinical and clinical applications. It was validated on synthetic, preclinical and clinical data. Furthermore, possibilities of the longer temporal sampling provided by blind deconvolution were analyzed. This can be used for improved spatial resolution and possibly for higher SNR. For easier deployment of the proposed methods into clinical and preclinical use, a software tool for perfusion data processing was designed.
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Measurement and analysis of cardiovascular parameters
Filipová, Petra ; Smital, Lukáš (referee) ; Kratochvíla, Jiří (advisor)
This bachelor´s thesis illustrates the basic diagnostic procedures for ECG analysis in clinical practice. It contains the verification of statistical hypotheses, automatic detection of the RR intervals using three different QRS detectors and heart rate from the ECG und other analyses in time and frequency domain. The validation of detection efficiency is investigated. Heart rate variability analyses are shown in time and frequency domain too. Analyses are done in Matlab, the graphical interface in Maltab GUIDE was done too and includes all of the created functions in time and frequency domain. For the purpose of evaluation methods the real data were measured according to the created acquisition protocol.
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The measurement of cardiovascular parameters
Žáková, Monika ; Kratochvíla, Jiří (referee) ; Nováková, Zuzana (advisor)
This paper summarizes the problems of physiology of the cardiovascular system, with a focus on cardiovascular measurements during physical activity. It describes the diagnostic tools Cardiovit AT-104 (Schiller, Switzerland) and PowerCube (Ganshorn, Germany), used to spiro-ergometry measurements. It provides options to export data and work with them. It proposed protocol for the measurement of a small group of volunteers, by which we measure basic diagnostic parameters before, during and after physical activity. The MATLAB application is created, allowing clear analysis of measurement records. The final part contains a statistical assessment affected by physical activity on the measured parameters and a comparison of results with the available literature.
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Modelling of parametric arterial input function in perfusion imaging
Černý, Štěpán ; Jiřík, Radovan (referee) ; Kratochvíla, Jiří (advisor)
The task of this bachelor’s tesis is to study the subject in the area of perfusion imaging based on dynamic imaging with T1 contrast. Aims is primarily on the role of the arterial input function. Principles phenomenon of dynamic magnetic resonance measurements are discribed. The role of contrast media and their influence on the relaxation time T1 are described. It is also described problems perfusion analysis, measurement and mathematical modeling of arterial input function and perfusion acquisition parameters. In the experimental part, there is modeled several models of arterial input function and their evaluation. Further the creation program for the approximation real measurement of arterial input function created models and the integration of this program into a graphical interface created for work with models. Was also verified the functionality of the program and evaluate the success of approximations for individual models.
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Analysis of measured parameters of the cardiovascular system
Lysoň, Jakub ; Vítek, Martin (referee) ; Kratochvíla, Jiří (advisor)
This bachelor thesis talks about the measurement of heart electrical activity by twelve lead ECG. The diagnostic system Biopac is used for measurement, featured by the computer program Acqknowledge. The own authentic method is designed to detect effect of load on increasing in blood pressure and heartbeat. Using a statistical procedure for testing hypotheses in this area the measurement results will be evaluated. For the analysis of measured data in time and frequency domain was used program Matlab, in which the measured results were imported. It was created functions that are implemented in an medium of Guide to the graphic design program.
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Scanning a analysing of heart electrical activity and blood pressure before and after the load
Vích, Daniel ; Kolářová, Jana (referee) ; Kratochvíla, Jiří (advisor)
The aim of bachelor’s thesis is familiarization with anatomy and physiology of heart, with setting to electrical activity, scanning EKG before and after the load with Biopac system, scanning of blood pressure before and after the load with auscultation, statistical analysis of acquired data and presentation of measured data in graphical interface Guide of Matlab system. According to the protocol of measurement, scanning of heart electrical activity with the Biopac system, and scanning of blood pressure, with auscultation, was realized before and after the load. Measured data was statistically analyzed with t-test to verify hypothesis, that there is an influence of the load on the watched parameters, and to show the process of statistical verification. Application of this method assumes normal distribution of data, that’s why data was at first tested by Chi-squared and Kolmogorov-Smirnov test to verify their normal distribution. In the next step data was imported into Matlab system. The presentation of measured data is realized in graphic interface Guide. The program contains time domain and spectral analysis, automatic detection of heart rate and analysis of heart rate variability.
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Scaling of arterial input function in DCE-MRI
Holeček, Tomáš ; Kolář, Radim (referee) ; Kratochvíla, Jiří (advisor)
Perfusion magnetic resonance imaging is modern diagnostic method used mainly in oncology. In this method, contrast agent is injected to the subject and then is continuously monitored the progress of its concentration in the affected area in time. Correct determination of the arterial input function (AIF) is very important for perfusion analysis. One possibility is to model AIF by multichannel blind deconvolution but the estimated AIF is necessary to be scaled. This master´s thesis is focused on description of scaling methods and their influence on perfussion parameters in dependence on used model of AIF in different tissues.
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