This thesis deals with a path planning using cellular automata algorithms in a rectangular grid environment. Theoretical part starts with an overview of commonly used approaches for path planning and later on focuses on existing cellular automata solutions and capabilities in detail. Implemented cellular automata algorithms and the commonly used path planning algorithms are together with a map generator described in the practical part. Conclusion of this thesis contains results completed in a special application.

The thesis begins with a theoretical part containing a general description of artificial pulmonary ventilation, invasive pulmonary ventilation and a detailed description of non-invasive pulmonary ventilation and chronic obstructive pulmonary disease. This section also focuses on a detailed description of non-invasive pulmonary ventilation in patients with chronic obstructive pulmonary disease. The aim of this thesis is to find out the real usability and success of non-invasive pulmonary ventilation in patients with chronic obstructive pulmonary disease received in 2018 at the department of ARO in the Hospital Jindřichův Hradec. The data was obtained from the patient documentation for 2018 from the ARO department and subsequently entered in the tables. The research found that in 2018, 162 patients had undergone the selected department, of whom 63 patients suffered from chronic obstructive pulmonary disease. Noninvasive pulmonary ventilation was used in 75 patients. Of the total number of non-invasive pulmonary ventilation applications, 30 were used in patients with chronic obstructive pulmonary disease. The success of non-invasive pulmonary ventilation in chronic patients reached 90 %. The main benefit is the fact that the number of patients with chronic obstructive pulmonary disease is increasing and that indeed chronic obstructive pulmonary disease is aggravated in the winter months. Another benefit is the finding that the success and true utility of non-invasive pulmonary ventilation in patients with chronic obstructive pulmonary disease is very good.

L'objectif de cette thèse est de développer l'imagerie de transfert de saturation des agents de contraste lipoCEST pour la détection de l'angiogenèse dans un modèle souris de tumeur cérébrale U87. Un lipoCEST offrant un seuil de sensibilité in vitro de 100 pM est optimisé afin de répondre aux contraintes de l'imagerie CEST in vivo. Grâce à la mise en place d'un dispositif expérimental dédié à l'imagerie CEST, nous évaluons les performances des lipoCEST pour détecter de façon spécifique l'angiogenèse tumorale. Nous montrons pour la première fois qu'il est possible de détecter un lipoCEST in vivo dans un cerveau de souris suite à une injection intraveineuse. De plus, l'utilisation d'un lipoCEST fonctionnalisé avec un peptide RGD permet de cibler spécifiquement l'intégrine ανβ3 surexprimée lors de l'angiogenèse tumorale. L'association spécifique du RGD-lipoCEST est confirmée grâce à des données d'immunohistochimie et de microscopie de fluorescence. Enfin, dans le but de tendre vers un protocole d'imagerie moléculaire par IRM-CEST, nous mettons en place un outil de quantification des lipoCEST. Cet outil repose sur la modélisation des processus d'échange de protons in vivo. Grâce à la prise en compte des inhomogénéités de champs B0 et B1 qui peuvent se révélées être délétères pour le contraste CEST, nous démontrons que la précision de notre outil de quantification est de 300 pM in vitro. La quantification des données CEST acquises chez la souris U87 permet d'estimer à 1,8 nM la concentration maximale en RGD-lipoCEST liés à leur cible moléculaire.

Dlouhodobé vdechování částic může přispívat ke vzniku nebo zhoršení nejrůznějších plicních onemocnění. Na druhou stranu, vdechování léčiv je často používanou metodou podávání léků proti astmatu a jiným nemocem dýchacího ústrojí. V obou případech je důležité dobře porozumět mechanismům, na jejichž základě funguje pohyb částic a jejich usazování v dýchacích cestách. Cílem této disertační práce bylo získat nová experimentální data depozice částic a analyzovat vliv tvaru částic a průtoku vzduchu na depozici. Byla studována depozice porézních a vláknitých částic v realistickém modelu dýchacích cest. Porézní částice byly vyrobeny různými metodami, např. sprejovým sušením nebo metodou krystalizace. Takto vyrobené částice byly použity při depozičních experimentech. Detekce částic byla provedena pomocí UV/VIS spektrofotometrie. Vláknitý aerosol byl vytvořen rozdrcením skelné vaty. Takto vzniklé vláknité částice byly několikrát prosety přes řadu sít a dále roztříděny podle délky pomocí klasifikátoru pracujícím na principu dielektroforézy. Následná depozice byla vyhodnocena použitím mikroskopie s fázovým kontrastem. Ke zrychlení analýzy byl vyvinut program, který dokáže na základě analýzy obrazu najít a spočítat vlákna. Výsledky experimentu byly použity k určení depozičních charakteristik. S jejich pomocí pak byl kvantifikován vliv tvaru částic a průtoku na míru usazování. Depoziční účinnost částic rostla v závislosti na Stokesově čísle, což poukazuje na vliv setrvačnosti při usazování částic. Bylo prokázáno, že depoziční účinnost porézních částic je podobná té u částic kulových při stejném Stokesově čísle. Vláknité částice se usazovali méně efektivně v porovnání s kulovými částicemi majícími stejné Stokesovo číslo. Jelikož byly okrajové podmínky dostatečně popsány a model plic je k dispozici i v digitální podobě, je možné data použít k validaci výsledků numerických simulací.

This thesis deals with the segmentation of lung parenchyma and extraction of airways tree from three dimensional CT scans. The external mask of the lungs is created and subsequently used to ease the process of airway segmentation. In this work, some published methods for airways segmentation are described with focus on one, which is described more in detail and also implemented in MATLAB. The proposed approach is based on morphological grayscale reconstruction. Method is tested on the real patient CT scans and finally, the results are discussed.

Multi-Agent Path Finding (MAPF) is the task to find efficient collision-free paths for a fixed set of agents. Each agent moves from its initial location to its desired destination in a shared environment represented by a graph. The classical definition of MAPF is very simple and usually does not reflect the real world accurately. In this thesis, we try to add several attributes to the MAPF definition so that we overcome this shortcoming. This is done in several steps. First, we present an approach on how to model and solve MAPF via reduction to Boolean satisfiability using Picat programming language. This provides us with a useful model that can be easily modified to accommodate additional constraints. Secondly, we modify MAPF to portray a more realistic world. Specifically, we allow new agents to enter the shared environment during the execution of the found plan, and we relax the requirement on the homogeneousness of the shared environment. Lastly, we experimentally verify the applicability of the novel models on real robots in comparison with the classical MAPF setting.

For a thorough investigation of metabolic changes in cases of increased activity or disease, a high-resolution imaging modality would be of high-value. Conventional MR-based metabolite mapping techniques suffer from low spatial resolution and poor sensitivity to low concentrated metabolites. In this work, a novel optimization approach for high-resolution metabolic imaging by means of chemical exchange saturation transfer (CEST) and nuclear Overhauser effect (NOE) will be introduced. The general term of saturation transfer comprises CEST, NOE and magnetization transfer (MT). It describes the transfer of saturated magnetization from low concentrated solute metabolites to bulk water, after frequency selective RF irradiation was applied. The strong enhancement of attenuation effects—observed in a Z-spectrum—can be used to detect changes in metabolite concentrations. The vast complexity of in vivo tissue heavily distorts the baseline in Z-spectra. With a background spin system, modeled from a scout acquisition, saturation pulse amplitudes for each frequency offset were modulated, such that a specific target signal intensity was achieved. Further, a framework for a retrospective look-up correction of magnetic field inhomogeneities and background spin system deviations was developed. The approach of a prospective baseline enhancement (PROBE) was investigated by means of sensitivity and specificity in vitro. It was subsequently translated into a clinical setting at 3 T. A high-resolution mapping of elevated lactate in ischemic regions of acute stroke patients became feasible.

121 9. Summárý Purpose: This study was designed to evaluate the role of interventional radiology in liver transplantation programme. The aim is to present our experience, technical outcomes and long-term clinical results with chemoembolization of hepatocellular carcinoma in patients before liver transplantation and with percutaneous treatment of vascular and biliary complication after orthotopic liver transplantation. Methods: Twenty five patients (17 men, 8 women, mean age 57.76 years) with HCC were scheduled for TACE prior to liver transplantation from 2008 to 2012. Twenty three procedures were performed, 7 c-TACE in 2008 and 16 DEB TACE in next years. Thirty patients (13 men, 17 women, mean age 46.4 years) with biliary strictures after liver transplantation without endoscopic access possibility were treated with balloon dilatation and biliary duct drainage from 1996 and 2010. Twenty patients (13 men, 7 women, mean age 45.25 years) were treated with PTA/stent due to hepatic artery stenosis after liver transplantation between 1996 and 2011. Stents were placed to the hepatic/celiac artery in 16 PTAs, balloon dilatation alone was performed in 7 stenosis due to tortuosity of the vessel. Results: Liver transplantation was performed to 20 patients after TACE. Only one patient (4.5 %) was excluded from waiting...

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Stroke is one of the leading causes of death and adult disability worldwide. The major therapeutic intervention for acute ischemic stroke is the administration of recombinant tissue plasminogen activator (rtPA) to help to restore blood flow to the brain. This has been shown to increase the survival rate and to reduce the disability of ischemic stroke patients. However, rtPA is associated with intracranial haemorrhage and thus its administration is currently limited to only about 5% of ischemic stroke patients. More advanced imaging techniques can be used to better stratify patients for rtPA treatment. One new imaging technique, chemical exchange saturation transfer (CEST) magnetic resonance imaging, can potentially image intracellular pH and since tissue acidification happens prior to cerebral infarction, CEST has the potential to predict ischemic injury and hence to improve patient selection. Despite this potential, most studies have generated pH-weighted rather than quantitative pH maps; the most widely used metric to quantify the CEST effect is only able to generate qualitative contrast measurements and suffers from many confounds. The greatest clinical benefit of CEST imaging lies in its ability to non-invasively measure quantitative pH values which may be useful to identify salvageable tissue. The quantitative techniques and work presented in this thesis thus provide the necessary analysis to determine whether a threshold for the quantified CEST effect or for pH exists to help to define tissue outcome following stroke; to investigate the potential of CEST for clinical stroke imaging; and subsequently to facilitate clinical translation of CEST for acute stroke management.