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Optimization of preoperative and surgical treatment of carcinoma of the esophagus and esophagogastric junction: The use of PET/CT in the diagnosis and evaluation of the effectiveness of preoperative chemotherapy and the technique of anastomotic construction as a factor of postoperative complications after esophagectomy
Haruštiak, Tomáš ; Stolz, Alan (advisor) ; Šimša, Jaromír (referee) ; Vrba, Radek (referee)
Key words: adenocarcinoma of the esophagus and esophagogastric junction, neoadjuvant chemotherapy, PET/CT, histopathological response, technique of esophagogastric anastomosis, anastomotic leak, anastomotic stricture Previous studies have shown that preoperative chemotherapy of locally advanced AEG is beneficial only for patients with a good histopathological response, the so-called responders. The aim of the first part of the thesis was to prospectively verify whether positron emission tomography (PET/CT) could be used for early identification of histopathological non- responders, who could be spared ineffective neoadjuvant treatment. Our study did not prove that the early metabolic response, expressed as the percentage change of the consumption of glucosis on PET/CT performed before (PET1) and 12 to 22 days after the start of the first cycle of preoperative chemotherapy (PET2) correlated with the histopathological response in the resection specimen in the entire population of 90 patients. In a post hoc explorative analysis we found the correlation between metabolic and histopathological response in a subgroup of patients with PET2 performed ≤16 days after the start of the therapy, but this hypothesis needs to be prospectively validated. Our study suggests that PET/CT performed after the first...
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Sex assessment of skull using exocranial meshes from CT scans
Musilová, Barbora ; Brůžek, Jaroslav (advisor) ; Friedl, Lukáš (referee)
Sex estimation is a challenging problem in both forensic anthropology and bioarchaeology. Sexual dimorphism is most noticeably displayed by the pelvis; however in instances when it is not preserved, sex is estimated by skull. There is a multitude of approaches that use the skull, however, their population specificity and variable sexual dimorphism oscillation reduces their effectiveness (Bruzek and Murail, 2006). We base our contribution on the study by Abdel Fatah et al. (2014) that estimates sex based on exocranial and endocranial surfaces with a high success rate of 97%. Our approach uses anonymized CT scans of skulls from recent french population, from which the exocranial surface was segmented. On these surfaces, CPD-DCA (Dupej et al., 2014) was performed. We analyzed both form and shape (form after size normalization) of these surfaces in 104 skulls (53 males, 51 females) aged 18 to 92 years. The mean age was 58 years in females and 52.46 years in males. Classification was performed using support vector machines (SVM) with a radial kernel. Leave-one-out crossvalidation was also applied. The highest success rate (87.5 %) was achieved with the first 27 principal components of form. Classification of shape was less accurate by only 2 %. Even though our success rate was lower than that of Abdel...
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Segmentation of cortical parts of vertebrae
Janštová, Michaela ; Kolář, Radim (referee) ; Jakubíček, Roman (advisor)
This thesis deals with a segmentation of cortical parts of vertebrae from CT image datas in programming software called MATALB. Issues about segmentation techniques are described, especially „level-set” method and its modification DRLSE. This method was chosen because of informations from articles published in spcialized publications and also thanks to its plentiful usage and satisfactory results. In the end of this paper is designed method tested on real CT datas.
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Segmentation and density estimation in femur
Horáček, Jan ; Maršálek, Lukáš (advisor)
Title: Segmentation and Density Estimation in Femur Author: Jan Horáček Department: Department of Software and Computer Science Education Supervisor: Mgr. Lukáš Maršálek Supervisor's e-mail address: lukas.marsalek@mff.cuni.cz Abstract: There are two basic ways of surgical treatment of femoral neck frac- ture - total endoprosthesis or a special metal screw in the bone. In case of a dense enough bone the screws are preferred. But for a too sparse bone, the screw may cut through the femoral head, which results in further surgical operations. We present a novel method for femoral head density measurement, which serves as another hint for the doctor's decision, whether to apply a screw or total endo- prosthesis. Our approach is based on semi-automatical femoral head segmenta- tion from CT dataset based on finding optimal path through polar coordinates on axial slices. The cost function is based on a combination of corticallis proper- ties, mostly the directional behavior of 3D gradients and their size in 2D slices, where they form typical "channels". The final volume is computed using filling and morphological algorithms and its properties are further measured. The final implementation was experimentally validated on RTG clinic of Bulovka hospital and allows radiologists to intuitively and accurately estimate...
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The role of radiologist assistant in radioiodine diagnostics and treatment of thyroid cancer
Hrbek, Jaroslav ; Táborská, Kateřina (referee) ; Vlček, Petr (advisor)
The bachelors thesis on the task of a radiological assistant during radioiodine diagnostics and treatment of thyroid gland carcinomas deals with the issue of thyroid gland carcinomas in the Czech Republic. It contains a brief overview of the types of carcinomas that affect the thyroid gland, their classification, diagnostics and therapy, concentrating on utilisation of modern examination methods and therapeutic practices, including among others application of radioiodine. The thesis also contains cases of four patients with similar diagnoses, the comparison of the development of whose respective illnesses I found interesting. Last but not least, the thesis includes a number of annexes comprising among others tables with important instructions for patients before and after application of radioiodine, and photographs from the site where the radioiodine application takes place Powered by TCPDF (www.tcpdf.org)
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Noise reduction for low dose CT data
Holub, Zbyněk ; Odstrčilík, Jan (referee) ; Chmelík, Jiří (advisor)
The aim of this work is comparing of methods which are used for filtration of low dose CT images. This filtration is realized due to suppress of noise in final image and better visble of details. This work contains design and realization of selected filtration methods. Wiener´s correction coefficient and filtration with usage of WAVELET TRANSFORM are introduced in detail view. These methods are created in Matlab®; with the option to set para-meters of filteres. The filters are tested on 3D CT lungs image data. In the end of this work is a ranking of filter‘s quality and choosen of the most optimal approach.
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Acquisition and Detection Geometry of the CT X-ray Imaging Process
Rusz, Jakub ; Harabiš, Vratislav (referee) ; Drastich, Aleš (advisor)
The basic components of acquisition and detection geometry of a 3rd generation single slice CT scanner are described here. Then the high contrast spatial resolution of the imaging process is explained and what effects does the setting of acquisition and detection geometry changes in the limiting high contrast spatial resolution. At the end a laboratory exercise and a simulator is presented, which will show and explain these effects.
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Segmentation of 3D medical images based on region growing method
Kantorová, Martina ; Krátká, Lucie (referee) ; Harabiš, Vratislav (advisor)
This bachalor thesis deals with a region growing approach for segmentation of volumetric medical images. The aim is to present basic methods of segmentation of image data and to focus in particular on the approach of region growing. The input data are brain slices of magnetic resonance imaging which can be visualized using the browser into the three basic planes. The viewer is implemented in MATLAB programming environment. Image segmentation is realized by seeded region growing.
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Java Client for 3D Displaing of Medical Image Data
Bireš, Jiří ; Štancl, Vít (referee) ; Kršek, Přemysl (advisor)
The thesis considers use of Java language in interactive 3D displaying of medical image data. Main point is to find out advantages of using this language in medical visualisations and find suitable tools for its future usage. At the conclusion it evaluates advantages and disadvantages of used technologies and suggests possible development of the appliacation
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Volume Rendering Using Programmable HW
Jošth, Radovan ; Kršek, Přemysl (referee) ; Herout, Adam (advisor)
This work describes and implementing method for volume data rendering. Main purpose of this work is visualization of scanned 3D data with some current method used for the 3D volumetric scanning. The 3D volumetric scanning is mainly used in medicine and chemistry. System is using programmable pipeline of current graphic cards, which provides us fast parallel work with large volumetric data. This paper introduces some basics about the volumetric rendering and scanning, describes design and at the end, the implementation steps. Result of this project is application which renders volumetric data with OpenGL.
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