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MR image data processing in study of tissue cultures
Bidman, Petr ; Šmirg, Ondřej (referee) ; Gescheidtová, Eva (advisor)
Techniques based on principle of nuclear magnetic resonance (NMR) belong to the most modern methods for studying physical, chemical and biological properties of materials [1]. Their universality predestinates them for application in a wide range of scientific disciplines, e.g. in medicine to study properties of tissues. Advantages of techniques utilizing principle of NMR consist in their noninvasiveness and thoughtfulness to human health or studied material. In addition, no undesirable effects of magnetic force field have been so far proved by research. Objectives of this Diploma Thesis are evaluation of MR images of tissue cultures and determination of protons amount included in them. Theoretic part of the Thesis is devoted to the bases of NMR and provides basic overview of MR methods. The spin echo method (SE) is described in more details, including the process of assessment of technique’s parameters, e.g. general magnetization. Practical part of Diploma Thesis is focused on determination of integral of image intensity of clusters of early somatic embryos. Intensity integrals characterizing number of protons in growing cluster were calculated from MR images of spruce embryos contaminated by lead. The intensity of an image weighted by spin density is proportionate to the number of proton nuclei in the chosen slice. The Thesis describes further evaluation of relaxation time T2 from MR images weighted by spin density. Following part is dealing with determination of diffusion from MR images with application of compensation methods, three-measurement arrangement and presentation of obtained results. Images were processed by use of MATLAB and MAREVISI programs.
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Processing of images of early spruce needles scanned by MR technology
Raichl, Jaroslav ; Říha, Kamil (referee) ; Gescheidtová, Eva (advisor)
This semester project deals with filtering of the images detected by use of NMR obtained by NMR application measurement of nuclear magnetic resonance (NMR). This thesis includes the theory of nuclear magnetic resonance, digital filters, basic digital filter banks structures, theory of Wavelet transformation and description of Signal to Noise Ratio calculation. Basic procedure of the MR signal denoising is summarized in the theoretical part of the thesis. The denoising of the images detected by nuclear magnetic resonance is described. In experimental part filtering methods for images denoising are described, which are implemented in program Matlab. These methods are based on Wavelet transformation, digital filter banks with proper thresholding. Effectiveness of filtering methods designed was verified on 2D NMR images. All of these 2D images were measure on MR tomography in the Institute of Scientific Instruments Academy of Science of the Czech Republic in Brno.
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Měření relaxačních časů sodíkových iontů metodami magnetické resonance
Mikotová, E. ; Bartušek, Karel ; Gescheidtová, E.
Nuclear Magnetic Resonance (NMR) experiments enable describing of the structure and the internal mobility of a wide spectrum of materials and systems from solutions, very soft and movable gels over synthetic polymers to organic and inorganic crystals and very hard rigid glass. The paper deals with a study of the relaxation times of the nearly liquid and gel electrolytes with content of natrium ions by the NMR technique. Newly designed method of solid electrolytes samples compounding and a suitable method for measurement of the relaxation times during the samples solidification were established.
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Measurement the induction of magnetic field around an applicator for magnetotherapy
Bartušek, Karel ; Gescheidtová, E. ; Steinbauer, M.
The paper deals with measuring magnetic induction by imaging techniques based on magnetic resonance (MR) and describes experimental results od mapping the magnetic induction of a dermatological applicator for magnetotherapy performed by MR imaging techniques. The results are compared with theoretical calculation and with measurement carried out with an ordinary magnetometr. The conclusion derived from the measurement will be used in the design of a new applicator with complex electronic control of magnetic field.
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Filtering of MR signal in NMR tomography
Bartušek, Karel ; Geschneidtová, E.
The paper presents the comparison of three filtering techniques tested for the nuclear magnetic resonance tomography signal processing. FIR filtering, Wavelet and adaptive filtering were applied in a tomograph designed and produced in the Institute of Scientific Instruments of the Academy od Sciences of the Czech Republic. The test results obtained are described in the next chapters.
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