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Possibilities of the object surface determination in tomographic data set
Kalasová, Dominika ; Novotný, Jan (referee) ; Zikmund, Tomáš (advisor)
This work studies the possibilities for determining surfaces of objects in tomographic data. This procedure is important for post-processing - object visualization, coordinate measuring, export to STL file format etc., and it is complicated due to tomographic artifacts, porosity of material, material inhomogenities, and low-quality data. The possibilities of the surface determination in VGStudio MAX 2.2 software are described and demonstrated on steel fiber-reinforced concrete sample.
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Modern trends in radiographic procedures and methods in defectoscopy
Skřivánková, Vendula ; Vlašic, František (referee) ; Juliš, Martin (advisor)
Presented thesis deals with modern trends and techniques in radiographic methods of crack detection which are recently used in engineering practice. In the first part, conventional (analogue) radiography principles based on creating a visible image of tested object to radiographic film are discussed. The next part is aimed to the digital radiography and radioscopy. To digitize existing X-ray film images, application of storage phosphor plates (CR), flat panels (DR) and computed tomography (CT).
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Segmentation of soft tissues in facial part of mouse embryos from X-ray computed microtomography data
Janštová, Michaela ; Harabiš, Vratislav (referee) ; Chmelík, Jiří (advisor)
This diploma thesis deals with a segmentation of soft tissues in facial part of mouse embryos in Matlab. Segmentation of soft tissues of mouse embryos was not fully automated and every case needs a specific solution. Solving parts of this issues can provide valuable data for evolutionary biologists. Issues about staining and segmentation techniques are described. On the basis of accessible literature otsu thresholding, region growing, k-means clustering and segmentation with atlas were tested. In the end of this paper are those methods tested and evaluated on 3D microtomography data.
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Optimization of X-ray computed tomography method for imaging of low-density materials
Maleček, Lukáš ; Oberta, Peter (referee) ; Zikmund, Tomáš (advisor)
X-ray computed tomography is a technique enabling three-dimensional non-destructive imaging of the internal structure of measured objects. This imaging method has become a standard tool utilized in various fields, including medicine, industry, and science. Conventional X-ray computed tomography is based on the absorption of X-rays as it is passing through the measured object. However, this conventional imaging approach has its limitations, particularly when imaging objects with low density that causes only low X-ray attenuation. In such cases, sufficient contrast between the measured object and the background is not achieved. This thesis focuses on the optimization of phase contrast imaging, which utilizes phase changes of radiation as it is passing through the sample to overcome the limitations of absorption-based computed tomography. The detection of phase changes is achieved in the thesis using the propagation-based method. The main goal is to develop a methodology for finding the optimal parameters for the acquisition of tomographic data and also for the following processing of obtained X-ray projections. The results are qualitatively and quantitatively evaluated to assess the benefits of the developed methodology.
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Possibilities the use of CT and MRI in ENT diagnostics
SVOBODA, David
The bachelor's thesis deals with the possibilities use of CT and MRI in ENT diagnostics. The main goal is to introduce and give information about the use of various viewing methods in ORL diagnosis, with a main focus on CT and MR viewing methods. In the theoretical part of the thesis, we introduce the field of otorhinolaryngology and a brief introduction into the history of this field. Then we talk about the basic equipment of an ORL doctor's office and the use of various basic examinations. Continuing, we talk about diagnostic methods that can be used in ORL - RTG, CT, NMR, sonography and scintigraphy. Finally, we briefly discuss the anatomy, illness and diagnosis of the airways, throat and neck. The Following goals had been established: To analyse the possibilities of using CT and MRI during the ORL diagnostics. Determine the level of awareness of the non-expert audience about the process of CT and MRI and ORL diseases. Then, hypothesis had been determined, which reads as follows: respondents have sufficient/enough information about the CT and MR examination and respondents have experience with diseases in the ORL area. For the empirical part of the thesis, we chose an anonymous questionnaire whose results were solely intended for the purposes of this thesis. The main purpose of the study was to find out about the knowledge the patients had about the various diagnostic procedures. The result is that the general population is sufficiently informed about the entire diagnostic process, as well as its potential complications and shortcomings. Illnesses in ORL are relatively frequent, across all age groups. The most common diagnoses are ear infections, tonsillitis, and bronchitis. he most commonly used viewing methods are X-rays and ultrasounds or sonography.
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Development and evaluation of new cementless revision acetabular components for total hip arthroplasty / type TC /
Šťastný, Eduard ; Trč, Tomáš (advisor) ; Šponer, Pavel (referee) ; Pilný, Jaroslav (referee)
Development and evaluation of new cementless revision acetabular components for total hip arthroplasty / type TC / Objective: The aim of the clinical part of the study was to introduce a new revision oval cup type TC, and evaluate its reliability and utility in revision endoprosthesis. Due to the different structure of the implant, we aimed to objectively demonstrate the remodeling of bone tissue in its vicinity. In the experimental part of the work we verified the hypothesis that the use of locking screws has an effect on the bond strength of the implant with bone tissue, and therefore on the primary stability of the acetabular component. Method: We evaluated 31 patients that underwent revision hip surgery between 2004 and 2008. The mean follow-up was 7.1 years (range 5.3 to 9.3 years, minimum 5 years after surgery). Osteointegration of the implant and remodeling of bone tissue around the implant and its ribs were evaluated by digital radiography and computed tomography, and clinical results according to Harris. The experiment was based on the execution of pull-out tests after the implantation of TC cups in cadaveric bovine pelves. We evaluated the dependence of tensile forces in the axis of the implant on extraction of the metal cup from the bone bed. Four tests were conducted with the cup fixed...
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Digital forensic anthropology and sexual dimorphism of recent population os coxae: implication for sex estimation.
Mesteková, Šárka ; Brůžek, Jaroslav (advisor) ; Dobisíková, Miluše (referee)
This thesis uses the metric evaluation of 3D models created from CT images. The study is based on an examination of 51 males and 55 females CT scans from recent European population and also based on a metric data (10 linear measurements) of the same geographical provenance of the mid-20th century (n=113). The purpose of our research project is to determine the degree of sexual dimorphism in current population and compare the degree of sexual dimorphism in this geographic area in the middle of the last century. Intraobserver variabilities of linear measurements were less than 2%. Both groups were statistically tested. An index of sexual dimorphism (ISD) was used to assess the level of sexual dimorphism within each sample (Paris ISD = 8,28, Marseille ISD = 6,50). The two-sided t-test indicates that the degree of sexual dimorphism is not significantly different between population from the mid-20th century and recent population (p = 0,680). The secular trend was expressed by the z-score. The results showed that changes in the pelvic bone between the two groups are not significant, since neither one of the measurements does not exceed ±2 SD. Finally, we verified the reliability of method DSP ("Diagnose Sexuelle Probabiliste") for measurements deducted from CT-derived models. The results showed the...
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