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Contrast MRI perfusion imaging
Šejnoha, Radim ; Harabiš, Vratislav (referee) ; Krátká, Lucie (advisor)
This semestral thesis is focused on contrast MRI perfusion imaging using method of Dynamic Contrast-Enhanced MRI. It describes basic principles of nuclear magnetic resonance and puls sequences used in DCE MRI. The thesis contains a part dedicated to dynamic contrast imaging of phantom with experimental NMR device located at the Institut of Scientific Instruments of the ASCR in Brno. Results of measurements are analyzed based on models and reached perfusion parameters are discussed.
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Image registration using evolutionary algorithms
Kubalová, Eva ; Kozumplík, Jiří (referee) ; Mézl, Martin (advisor)
The diploma thesis deals with the image registration using evolutionary algorithms from metaheuristic optimization techniques which are considered recent and widely used. The frst part of the thesis contains theoretical description of components in image registration and later focuses on the ultrasound images. In that part, the thesis explains chosen evolutionary algorithms. Three optimization methods have been implemented, in particular genetic algorithm, particle swarm optimization and frey algorithm. Chosen similarity metrics for optimization are sum of squared dierences, cosine similarity and correlation coefcient. The main part of thesis includes testing of proposed methods with the evaluation of obtained results. These parameters are later used for optimization of real ultrasound sequences obtained by the contrast imaging.
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Graphical user interface for magnetic resonance data reconstruction
Marcin, Michal ; Rajmic, Pavel (referee) ; Mangová, Marie (advisor)
The aim of the bachelor thesis was to create graphical user interface for processing magnetic resonance data. For this purpose, the Matlab development environment was used. The basic principles of magnetic resonance, the ways of scanning and the graphical imaging as well as mathematical methods are described in the first part. The method of compression scanning and imaging of real images using laboratory mice is described in the text. In the second part of the thesis, the graphical user environment and its functions are described. The program is able to simulate and display the Shepp-Logan phantom model according to specified parameters. The created application allows the reconstruction and processing of simulated as well as real data.
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Deconvolution in perfusion imaging
Líbal, Marek ; Havlíček, Martin (referee) ; Bartoš, Michal (advisor)
The purpose of this study is to introduce the methods of the deconvolution and to programme some of them. For the simulation, the tissue homogeneity model and the model of arterial input fiction were used. These models were engaged as the test procedures with the aim of verify the functionality and utility of the Wiener filter, the Lucy-Richardson algorithm and the Singular value decomposition.
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Modelling for ultrasound perfusion imaging
Hracho, Michal ; Šikner, Tomáš (referee) ; Mézl, Martin (advisor)
This thesis deals with the possibilities of determining perfusion parameters of vascular system, using contrast-enhanced ultrasound imaging, which is non-invasive method. Properties of ultrasonography and use of contrast agents are briefly summarized. The methods selected for perfusions analysis were Bolus-tracking¬¬, Burst-replenishment and both of them combined – Bolus&Burst. Parametric models based on these methods were created for modelling an approximation of set perfusion parameters with the use of blind deconvolution.
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Phantom model for perfusion imaging
Borovičková, Michaela ; Harabiš, Vratislav (referee) ; Mézl, Martin (advisor)
This work focuses on issues relating to the perfusion analysis. The aim of this work is to perform experimental measurements of the phantom and then evaluate the perfusion curves. This curves are used to himation of perfusion hemodynamic parameters, which indicates important informatik about monitoring area. All processes associated with the designation and evaluation are performed in a program named Matlab. The output of work is a system that provides the reader into the problem of perfusion analysis and allows him to understand and know what is the meaning od analysis, what demands are placed on the evaluation and what is the result of this perfusion analysis.
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Increasing Resolution in Perfusion Magnetic Resonance Imaging Using Compressed Sensing
Mangová, Marie ; Polec,, Jaroslav (referee) ; Šmídl, Václav (referee) ; Rajmic, Pavel (advisor)
Perfusion magnetic resonance imaging is a medical diagnostic method which requires high spatial and temporal resolution simultaneously to capture dynamics of an intravenous contrast agent which is used to perfusion measurement. However, magnetic resonance imaging has physical limits which do not allow to have this resolution simultaneously. This thesis deals with compressed sensing which enables to reconstruct measured data from relatively few acquired samples (below Nyquist rate) while resolution required to perfusion analysis is increased. This aim could be achieved with suitably proposed apriory information about sensed data and model proposal. The reconstruction is then done as an optimization problem. Doctoral thesis brings several new reconstruction models, further proposes method to debias this estimates and examines influence of compressed sensing onto perfusion parameters. Whole thesis is ended with extension of compressed sensing into three-dimensional data. Here, the influence of reconstruction onto perfusion parameters is also described. In summary, the thesis shows that due to compressed sensing, temporal resolution can be increased with the fixed spatial resolution or spatial resolution can be increased with the fixed temporal resolution.
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Image segmentation of ultrasound images
Schwarzerová, Jana ; Odstrčilík, Jan (referee) ; Mézl, Martin (advisor)
This bachelor’s thesis deals with basic description of ultrasonography, principles of contrast-enhanced imaging and application of segmentation methods in ultrasound problematics. Some individual methods were implemented in Matlab, version R2015b. Algorithms were tested on synthetic images data, on ultrasound phantom images data and on real ultrasound images. Then the thesis was extended by ultrasound sequences segmentation.
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Graphical user interface for magnetic resonance data reconstruction
Marcin, Michal ; Rajmic, Pavel (referee) ; Mangová, Marie (advisor)
The aim of the bachelor thesis was to create graphical user interface for processing magnetic resonance data. For this purpose, the Matlab development environment was used. The basic principles of magnetic resonance, the ways of scanning and the graphical imaging as well as mathematical methods are described in the first part. The method of compression scanning and imaging of real images using laboratory mice is described in the text. In the second part of the thesis, the graphical user environment and its functions are described. The program is able to simulate and display the Shepp-Logan phantom model according to specified parameters. The created application allows the reconstruction and processing of simulated as well as real data.
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Image registration using evolutionary algorithms
Kubalová, Eva ; Kozumplík, Jiří (referee) ; Mézl, Martin (advisor)
The diploma thesis deals with the image registration using evolutionary algorithms from metaheuristic optimization techniques which are considered recent and widely used. The frst part of the thesis contains theoretical description of components in image registration and later focuses on the ultrasound images. In that part, the thesis explains chosen evolutionary algorithms. Three optimization methods have been implemented, in particular genetic algorithm, particle swarm optimization and frey algorithm. Chosen similarity metrics for optimization are sum of squared dierences, cosine similarity and correlation coefcient. The main part of thesis includes testing of proposed methods with the evaluation of obtained results. These parameters are later used for optimization of real ultrasound sequences obtained by the contrast imaging.
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