Vývoj metod pro detekci a redukci artefaktů u povrchových vysokofrekvenčních ultrazvukových obrazů
Development of methods for the detection and reduction of image artifacts during surface acquisition with high- frequency ultrasound
Typ dokumentu
diplomová prácemaster thesis
Autor
Hauprich Katharina
Vedoucí práce
Rožánek Martin
Oponent práce
Krupička Radim
Studijní obor
Biomedicínské inženýrstvíStudijní program
Biomedicínská a klinická technika (studium v angličtině)Instituce přidělující hodnost
katedra biomedicínské technikyObhájeno
2018-09-19Práva
A university thesis is a work protected by the Copyright Act. Extracts, copies and transcripts of the thesis are allowed for personal use only and at one?s own expense. The use of thesis should be in compliance with the Copyright Act http://www.mkcr.cz/assets/autorske-pravo/01-3982006.pdf and the citation ethics http://knihovny.cvut.cz/vychova/vskp.htmlVysokoškolská závěrečná práce je dílo chráněné autorským zákonem. Je možné pořizovat z něj na své náklady a pro svoji osobní potřebu výpisy, opisy a rozmnoženiny. Jeho využití musí být v souladu s autorským zákonem http://www.mkcr.cz/assets/autorske-pravo/01-3982006.pdf a citační etikou http://knihovny.cvut.cz/vychova/vskp.html
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Vývoj metod pro detekci a redukci artefaktů u povrchových vysokofrekvenčních ultrazvukových obrazů Function and aesthetic of human teeth take a high priority in everyday life. In order to produce a high-quality dental restoration, such as veneers, dental crowns or bridges, a particularly detailed impression of the prepared tooth region is needed. A high-frequency ultrasound based dental microscanner (S.CAI System, whitesonic GmbH, Aachen, Germany) has been proven to be a feasible system for this purpose. Nevertheless, as with other medical imaging modalities, sonography is prone to image artifacts. A strong degradation is given by air bubbles present in the coupling space. Due to the scanner movement, they cause a bowl-like artifact that is strongly dependent on the location of the bubble with respect to the beam focus. During signal processing, the artifact may be confused as originating from the tooth surface. Thus, air bubbles have to be detected to reduce their influence. Two indirect detection methods were developed. The outcome of the conceptual stage was given by a signal-based and an image-based technique that address the segmentation of the bowl artifact in the threedimensional space. The signal-based method was aiming at the recognition of amplitude changes within the recorded A-signals, while the image-based method was detecting elliptic structures in C-Mode images. Both procedures proof to be potential detection methods but show to be limited in their detection ability and robustness. Further developments are required to accomplish a feasible detection approach.
Kolekce
- Diplomové práce - 17110 [1011]