L'imagerie en tenseur de diffusion (DTI) est basée sur la mesure de la mobilité des molécules d'eau permettant l'analyse de la microarchitecture du tissu cérébral. Le trajet des fibres blanches peut être alors reconstruit par des méthodes de tractographie déterministes basées sur la direction principale de la diffusion. Toutefois elle repose sur des outils mathématiques complexes donnant un regard indirect sur les structures anatomiques, et sa validation est un enjeu majeur. Notre objectif a été de concevoir un objet-Test (OT) tri-Dimensionnel permettant la validation de la diffusion dans des faisceaux de fibres imitant l'organisation cérébrale. Cet OT se compose de trois modules: BOITE, SOLUTION, FIBRE réalisés en impression 3D. Il se compose de solutions de glucose et de fibres de dyneema orientées dans les trois orientations de l’espace. Nous nous sommes intéressés au développement d'une méthode de contrôle qualité des mesures quantitatives de diffusion dans le module SOLUTION. / Diffusion Tensor Imaging (DTI) is based on the measurement of water diffusion mobility in order to investigate brain microarchitecture and white fiber connectivity. The trajectory of white fibers bundles can be reconstructed by deterministic tractography methods depending on the principal direction of diffusion in tissu. However, tractography consist to complex mathematical algorithms reflecting an indirect visualization of white fibers. Our goal consisted to design a 3D phantom which imitates brain's diffusion properties, offering different degrees of diffusion mobility and imitating the organization of brain fibers. The phantom consists of three components 3D-Printing: BOX, SOLUTION, FIBER. The phantom was composed of various glucose solutions and dyneema synthetical fibers organized in all 3 directions. We developed a quality control of quantitative measurements for the SOLUTION's component. We have lead a comparison of fibers reconstruction between tractography and ground truth in FIBER's component. Results show that : ADC values were ranged on those brain values with glucose solutions; FA,

X-Ray Computed Tomography is irreplaceable medical imaging system. Quantitative evaluation is day to day routine used for clean run of this imaging system. The master’s thesis is focused on quantitative evaluation of first and third generation X-Ray CT. First of all is about subjective and objective evaluation of space and energetic resolution. Space resolution is evaluated in space and frequency domain. Energetic resolution is represent by low contrast resolution method. Application “Kvantitativní hodnocení kvality CT RTG zobrazení” created for this thesis is used for creation of reconstruction image and quantitative evaluation. This application was created with consideration of its usage in subjects about image processing. The master’s thesis contains results of quantitative evaluation X-Ray CT created with this application and proposal of lab work.

In our work we have studied the ultrasonic imaging systems and their use in ophthalmology, especially with the device Nidek 4000. We described ophthalmological examination methods. In addition, we are using the simulation program Field II. It simulated eye phantom and created his B-scan and biometry, where we compared the effects of different central frequency ultrasonic probes and different speeds of sound in the resulting values. We also created phantoms using agarose gel and materials of different properties. On phantoms, we studied the effect of the velocity of ultrasound in measurement results, effect of the concentration of the agarose gel to the velocity of sound. And we created phantoms simulating the human eye. Measurement protocol was created for use in teaching.

The thesis deals with physical principles of ultrasound with following specialization on ophtalmic ultrasound system Nidek Echoscan 4000 and its properties. And also it deals with description of investigative techniques in ophthalmology (A-mode, B-mode, biometry and pachymetry). Next, they was suggested procedures of measurement and that is spatial resolution (axial and lateral spatial resolution) and propagation speed of ultrasound depending on the temperature. Then these properties was tested on laboratory phantoms of eye – ETETECH LTD. and Multipurpose Ultrasound Phantom but on created phantoms of eye too, which will be made from agarose gel with build-in materail (fishing line, plastic film, plastic bag and rubber). At the end, measured values was processed in the generated program.

This master thesis deals with the measurement properties of ultrasound probes. Ultrasound probes and their parameters significantly affect the quality of the final image. Values of pa-rameters of the probes may change due to their use, because probes may be damaged and the final image may no longer be correct. For these reasons the measurements of parameters of probes are very important. In this master thesis there are described and implemented the possibility of measuring the spatial resolution, focal zone, the sensitivity of the probe and measuring the length of the dead zone. Two ultrasonic phantoms were used for measuring. In the practical part there was created the program called Mereni_parametru, which allows to determine the value of four parameters from captured images of the phantom. Further, there are listed and described measured values for five ultrasonic probes. Results for two of these probes are then compared with the parameters given by the manufacturers.

This paper presents basic principles of optical coherence tomography, review of applications and basic categorization of these systems. Paper also deals with the typical properties of images from optical coherence tomography, especially speckle pattern. This paper also provides an overview of the origin of speckle noise and utilization of its dependence on microstructure of probed tissue for image classification based on textural analysis. Experimental part of this paper consists of phantom preparation, data acquisition by OCT system, implementation of speckle analysis in MATLAB and of testing of its functionality on standard textural dataset and also on acquired image phantom data. Speckle analysis is used for phantom image data segmentation.

In this thesis the primary focus is on the evaluation of biomedical microwave sensor to be used in the muscle analyzer system. Lower muscle quality is one indicator that a patient can have sarcopenia. Therefore the muscle analyzer system can be a tool used in screening for sarcopenia. Sarcopenia is a progressive skeletal muscle disorder that typically affects elderly people. It is characterized by several different things, one of them is that there is an infiltration of fat into the muscle. At microwave frequencies the dielectric properties of fat are vastly different than the muscles. So, this fat infiltration creates a dielectric contrast compared to muscle without this fat infiltration that the sensors aim to detect. The muscle analyzer system is proposed to be a portable device that can be employed in clinics to assess muscle quality. The sensors are evaluated on their ability to distinguish between normal muscle tissue and muscle of lower quality. This is achieved via electromagnetic simulations, clinical trials, where the system is compared against established techniques, and phantom experiments, where artificial tissue emulating materials is used in a laboratory setting to mimick the properties of human tissues. In a initial clinical pilot study the split ring resonator sensor was used, but the results raised concerns over the penetration depth of the sensor. Therefore, three new alternative sensors were designed and evaluated via simulations. Two of the new sensors showed encouraging results, one of which has been fabricated. This sensor was used in a another clinical study.This study only had data from 4 patients, 8 measurements in total, meaning it was hard to draw any conclusions from it. The sensors used in the clinical setting as well as another were evaluated in the phantom experiments. Those experiments were exploratory because a wider frequency range was used, although some problems in the experiments were found. A secondary approach in this thesis is devoted to a data-driven approach, where a microwave sensor is simulated. The data from it is simulated and used to train a neural network to predict the dielectric properties of materials. The network predicts these properties with relatively high accuracy. However, this approach is currently limited to simulations only. Several ideas on how to improve this approach and extend it to measurements is given.

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Bakgrund Amputation innebär att individen förlorar en liten eller stor del av kroppen som inte kan ersättas. Orsaken till amputation kan vara kärlsjukdomar, diabetes samt trauma. Amputation kan medföra fysiska och psykiska förändringar i patientens liv. Omvårdnad av dessa patienter kan vara komplex, sjuksköterskan har i sin profession en betydande roll i mötet med patienten. Syfte Syftet var att beskriva patienters upplevelser och erfarenheter efter amputation av nedre extremitet. Metod En icke systematisk litteraturöversikt genomfördes utifrån Fribergs metodbeskrivning. Sjutton originalartiklar inhämtades via databaserna PubMed och Cinahl Complete. Valda artiklar, kvalitetsgranskades och analyserades genom en integrerad analysmetod. Resultat Efter sammanställning av de nitton studierna identifierades två övergripande rubriker: Fysiologiska upplevelser och erfarenheter, psykologiska upplevelse och erfarenheter. varje kategori hade två underkategorier. Eftersom vi undersöker patientens upplevelser och erfarenheter efter amputation har vi valt att inkludera flera faktorer som påverkar patientens livskvalitet såsom sexualitet, smärta, depression och kroppsbild. Dessutom har vi även valt att inkludera benprotesens samt ADLs funktion som en faktor eftersom funktionaliteten är en viktig del av livskvaliteten. Slutsats Amputation leder till stor förändring i patientens liv, kan orsaka lidande i både den fysiska och psykiska hälsan, och ger svårigheter i patientens framtida liv. Det är viktigt som sjuksköterska att förstå och ha kunskap om den påfrestning som uppkommer efter amputation för att ge den specificerade vård som behövs i samarbete med andra yrkesgrupper för att möjliggöra att patienten ska kunna återgå till ett så normalt liv som möjligt. / Background Amputation means that the individual loses a small or large part of the body which cannot be replaced. The cause of amputation can be vascular disease, diabetes and trauma. Amputation causes physical and mental changes in the patient's life. Patient care can be complex, therefore the nurse has a significant role when interacting with patients who have undergone amputation. Purpose The purpose was to describe patients experiences after amputation of the lower extremity. Method Non-systematic literature review was performed based on Friberg's method description. Seventeen original articles were obtained via the databases PubMed and Cinahl Complete. Selected articles were quality reviewed and analyzed through an integrated analysis. Results After compiling the seventeen studies, two main categories were identified: Physiological experiences and experiences, psychological experience and experiences. Each category had two subcategories. Because we examine and study the patient's experiences after amputation, we have chosen to include several factors that affect the patient's quality of life such as sexuality, pain, depression and body image. In addition, we have also chosen to include the function of bone prosthesis and ADL as a factor because functionality is an important part of the quality of life. Conclusions Amputation leads to great change in the patient's life, which can cause suffering in physical and mental health and difficulties in the patient's future life. It is important as a nurse to understand and have knowledge of the stress that arises after amputation to provide the specified care needed in collaboration with other professions to enable the patient to return to a normal life as possible.