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Simulation of ultrasound sequences in contrast mode
Staňková, Jana ; Mézl, Martin (referee) ; Harabiš, Vratislav (advisor)
This bachelor thesis deals with the principle of contrast imaging techniques for ultrasound imaging. In the first part there are described basic principles and characteristics of ultrasound waves for the understanding. It is also focused on ultrasound contrast agents used in contrast enhanced ultrasound imaging. The important part is the description of perfusion models with a focus on obtaining perfusion parametres and analyzing perfusion curves obtained by measuring the ultrasound contrast agent over time. The second part is devoted to designing a program for generating simulated ultrasound images and description of the simulation of 2D ultrasound tomograms.
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Optimization of the MRI chicken embryos measurements
Sedláčková, Gabriela ; Dražanová, Eva (referee) ; Krátká, Lucie (advisor)
This thesis deals with optimization of MRI measuring of phantoms containing the chicken embryo. The theoretical part of thesis is dedicated to the MRI fundamentals and description of pulse sequences. In the next part the options of keeping and monitoring the temperature are being discussed. The thesis also deals with design and realization of phantoms which are used for measuring. A browser of images captured by MRI was programmed in Matlab environment. The program allows users to look through the images with different settings of pulses sequences or kind of phantom. The final part of thesis describes the anatomical structures of chicken embryo and discussion of collected results.
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Hydrogel phantoms for ultrasound diagnostics
Cerevatova, Kristina ; Smilek, Jiří (referee) ; Pekař, Miloslav (advisor)
This bachelor thesis deals with properties and preparation of hydrogel phantoms used in ultrasound diagnostics. The main object of this work was to get acquainted with the production and problems of phantom models. The theoretical part of the thesis focuses on phantom characterization, the principle of ultrasound, and phantom manufacturing companies. The practical part focuses on production of phantom models in Dansk Fantom Service, and on own production in the laboratory. Then on these phantoms was studied the speed of ultrasound, attenuation, and other physical changes.
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Properties of ultrasound probes
Rusina, Michal ; Mézl, Martin (referee) ; Harabiš, Vratislav (advisor)
This master thesis deals with the measurement properties of ultrasound probes. Ultrasound probes and their parameters significantly affect the quality of the final image. Values of pa-rameters of the probes may change due to their use, because probes may be damaged and the final image may no longer be correct. For these reasons the measurements of parameters of probes are very important. In this master thesis there are described and implemented the possibility of measuring the spatial resolution, focal zone, the sensitivity of the probe and measuring the length of the dead zone. Two ultrasonic phantoms were used for measuring. In the practical part there was created the program called Mereni_parametru, which allows to determine the value of four parameters from captured images of the phantom. Further, there are listed and described measured values for five ultrasonic probes. Results for two of these probes are then compared with the parameters given by the manufacturers.
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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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Hydrogel fantoms in ultrasonic diagnostic
Chovancová, Aneta ; Sovová, Šárka (referee) ; Hurčíková, Andrea (advisor)
This Bachelor thesis is interested in hydrogel phantoms made from gelatin, agar and agarosa. The effect of food foil on the essential properties of gel matrixes such as drying and moulding has been investigated. These properties were investigated visually and gravimetrically. The speed of prepared gel matrixes was measured using high resolution ultrasonic spectroscopy depending on concentration. In the work, I follow up on the already performed Bachelor thesis [1], where gel matrices were measured in the environment of air and water. My gel matrices are dispensed to the machine's cell in a liquid state. Depending on the material used and the method of use of the food foil, gel matrixes prepared for visual and gravimetric evaluation from agar with a concentration of 3 % and 5 % without foil and with foil on the bottom were found to have a longer shelf life than other samples with the same use of foil. Gel matrixes of all three substances and all concentrations covered with food foil are able to last up to 20 days without massive drying and mould formation. The result of measuring the relative ultrasonic velocity of the hydrogels produced was found to increase the rate of spread of ultrasound for all measured substances as the concentration increased.
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Design and Realization of Phantom for MRI
Šablatura, Martin ; Čáp, Martin (referee) ; Nešpor, Dušan (advisor)
Paper studies the principles of MRI and composition of MR system. Main part of thesis focuses on design, mixing and measurement of solution for MR system phantom. Teoretical part of paper focuses on problematic of MRI and phantoms for MR system, including description of specific phantom, which is then realised. Paper contains methods for designing proposed kind of phantom and its followed measurement. Part of paper also focuses on mathematical models of elaboration of data aquired from measurements.
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CT X-ray quantitative evaluation
Novotný, Lukáš ; Malínský, Miloš (referee) ; Drastich, Aleš (advisor)
X-Ray Computed Tomography is irreplaceable medical imaging system. Quantitative evaluation is day to day routine used for clean run of this imaging system. The master’s thesis is focused on quantitative evaluation of first and third generation X-Ray CT. First of all is about subjective and objective evaluation of space and energetic resolution. Space resolution is evaluated in space and frequency domain. Energetic resolution is represent by low contrast resolution method. Application “Kvantitativní hodnocení kvality CT RTG zobrazení” created for this thesis is used for creation of reconstruction image and quantitative evaluation. This application was created with consideration of its usage in subjects about image processing. The master’s thesis contains results of quantitative evaluation X-Ray CT created with this application and proposal of lab work.
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Design and construction of MR phatoms for MRI
Daňová, Ľudmila ; Odstrčilík, Jan (referee) ; Kudlička, Petr (advisor)
The object of the thesis is the design of the static phantom used in the MRI. It solves the generation of the pictures obtained from the magnetic resonance and its physical principles. The thesis focuses on two types of phantoms - dynamic and static, and especially on phantom used for the LCModel. There is also information about components that will be used for the detection of the spectrums of the selected metabolites.
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Development of material for agar-based ultrasound brain phantom
Řehořková, Petra ; Smékalová, Monika (advisor) ; Holas, Ondřej (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Mentor: Mgr. Monika Smékalová, Ph.D. Consultant: MUDr. Michael Bartoš Student: Petra Řehořková Title of Thesis: Development of material for agar-based ultrasound brain phantom This thesis is concerned with the development of a material for an agar-based ultrasound phantom that would provide skill acquisition and experience in a manner approximating real surgery. The aim is to formulate and optimize the agar hydrogel preparation procedure, evaluate its acoustic properties and water loss during storage. A dependence was found between the amount of water evaporated during storage (4 weeks at 37 řC) and the glycerol content, which slows down the water loss from the samples in direct proportion. Based on the results, an agar gel (AG) formulation with 1% agar and 60% glycerol was selected for the acoustic properties measurements. During this experiment the microbial stability of AG was confirmed. The results of acoustic parameters measurements were evaluated, namely, speed of the ultrasound, attenuation coefficient and echogenicity of the samples as a function of content of scattering particles Al2O3 and SiC. It was shown that each type of particles affects grayscale value and attenuation coefficient in a...
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