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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Behov och förutsättningar till kompetensutveckling för röntgensjuksköterskor : En intervjustudie

Wu, Erik, Nordin, Elina January 2017 (has links)
Bakgrund: Yrket röntgensjuksköterska är under ständig utveckling i Sverige gällande kompetensutveckling. Internationellt sett finns det många vägar att gå för röntgensjuksköterskor. Man kan till exempel vidareutbilda sig beskrivande radiograf. Utbildningarna har uteslutande gett positiva resultat. På grund av förändringar bland patienter måste vården utvecklas, detta gäller även röntgenverksamheten. I Sverige har man, trots den internationella utvecklingen, ännu inte fullt ut sett behovet. Syfte: Syftet med studien är att ta reda på vilket behov samt vilka förutsättningar till kompetensutveckling det finns på olika sjukhus för röntgensjuksköterskor. Metod: Studien är en kvalitativ intervjustudie med semi-strukturerade frågor. Ett strategiskt urval gjordes med inklusions- och exklusionskriterier. De kvalitativa intervjuerna utfördes per telefon eller i direkta möten och samtalen spelades in för att sedan analyseras med kvalitativ manifest innehållsanalys. Resultat: Det har varit omväxlande svar från deltagarna. De deltagande har varierande haft stora och små behov av kompetensutveckling för sina röntgensjuksköterskor. Bristen på personal är påtaglig. Alla deltagare uttryckte att de hade möjligheter och förutsättningar för att deras röntgensjuksköterskor skulle få kompetensutveckling även om utbudet varierade. Resultatet visar att kompetensutveckling behövs inom alla områden. Trots detta uttrycker inte alla sjukhus att kompetensutveckling är viktigt för deras verksamhet. Slutsats: Kompetensutveckling för röntgensjuksköterskor är ett stort ämne. Det finns mer att ta reda på och det finns många utvecklingsmöjligheter. Det finns ett behov att kompetensutveckla anställda röntgensjuksköterskor för att få en förbättring i sin profession, vilket leder till utveckling både individuellt som röntgensjuksköterska och tillsammans som röntgenavdelning. / Background: Profession as radiographer is constantly developing in Sweden valid skills development. There are many different ways in order to improve the profession internationally. One can, for example, take advanced practicing to become a reporting radiographer. The advanced practicing has exclusively showed positive results. Nowadays the patients are changing in conditions rapidly that the healthcare industry needs to adapt itself. Even the international development for radiographers seems bright, the need is yet fully realized in Sweden. Purpose: The purpose of this study is to find out which needs and possibilities are available for Swedish radiographers to improve and develop their own professional skills. Method: A qualitative interview study with semi-structured questions. The participants were selected by inclusions and exclusions. The interviews were conducted by telephone or physical meetings and the interviews were recorded and analyzed using qualitative content analysis manifest. Results: The responses from the participants have been varied. Lack of radiographers is palpable. All participants expressed that they had opportunities and possibilities for their radiographers to receive an advanced practicing in skills development even though the supply varied. The result shows that skills development is needed in all areas. Despite this, all hospitals do not express that skill development is important for their radiology department. Conclusion: Advanced skills development for radiographers is an interesting topic. There are more to figure out valid skill development. There is a need to develop radiographers in order to improve individually and together as X-ray department.
232

Hybrid PET/MRI Nanoparticle Development and Multi-Modal Imaging

Hoffman, David 03 December 2013 (has links)
The development of hybrid PET/MRI imaging systems needs to be paralleled with the development of a hybrid intrinsic PET/MRI probes. The aim of this work was to develop and validate a novel radio-superparamagnetic nanoparticle (r-SPNP) for hybrid PET/MRI imaging. This was achieved with the synthesis of superparamagnetic iron oxide nanoparticles (SPIONs) that intrinsically incorporated 59Fe and manganese iron oxide nanoparticles (MIONs) that intrinsically incorporated 52Mn. Both [59Fe]-SPIONs and [52Mn]-MIONs were produced through thermal decomposition synthesis. The physiochemical characteristics of the r-SPNPs were assessed with TEM, DLS, and zeta-potential measurements, as well as in imaging phantom studies. The [59Fe]-SPIONs were evaluated in vivo with biodistribution and MR imaging studies. The biodistrubution studies of [59Fe]-SPIONs showed uptake in the liver. This corresponded with major MR signal contrast measured in the liver. 52Mn was produced on natural chromium through the 52Cr(p,n)52Mn reaction. The manganese radionuclides were separated from the target material through a liquid-liquid extraction. The αVβ3 integrin binding of [52Mn]-MION-cRGDs was evaluated with αVβ3 integrin solid phase assays, and the expression of αVβ3 integrin in U87MG xenograft tumors was characterized with fluorescence flow cytometry. [52Mn]-MION-cRGDs were used for in vivo PET and MR imaging of U87MG xenograft tumor bearing mice. PET data showed increased [52Mn]-MION-cRGD uptake compared with untargeted [52Mn]-MIONs. ROI analysis of PET and MRI data showed that MR contrasted corresponded with PET signal. Future work will utilize [52Mn]-MION-cRGDs in other tumor models and with hybrid PET/MRI imaging systems.
233

Stråldos till personal vid hantering av diagnostiska radiofarmaka vid förberedelse och undersökning av patient / Radiation dose to personnel when handling diagnostic radiopharmaceuticals in preparation and in examination of patient

Kangas, Elina, Ucar, Berfin January 2017 (has links)
No description available.
234

För och nackdelar med CT lågdos protokoll : En kvalitativ litteraturstudie

Ange Marie, Ingabire, Mina, Narmashiri January 2017 (has links)
Bakgrund: Antal röntgenundersökningar som utförs med Computer Tomografi (CT) ökar ständigt i sjukvården, vilket har lett till en ökad mängd farlig strålning som patienter och vårdpersonal utsätts för och därmed följer en rad risker. Därför är det eftersträvansvärt att minimera denna stråldos men även bibehålla bildkvalité och diagnostisk säkerhet. Detta kommer dock med en mängd utmaningar som kräver nya tekniker och protokoll. För att dessa ska appliceras korrekt krävs även att den ansvariga vårdpersonalen besitter god kunskap inom området.  Syfte: Syfte med denna studie är att beskriva fördelar och nackdelar med lågdos CT (LDCT) vid buk undersökningar. Metod: Den systematiska litteraturstudien sammanställer vetenskapliga artiklar från bland annat PubMed vars kvantitativa eller kvalitativa svar anses kunna besvara den kvalitativa frågeställningen.  Resultat: Lågdosprotokoll för CT ger i många fall en liknande diagnostisk säkerhet som konventionell CT samtidigt som dosen sänks kraftigt. Dock begränsas effektiviteten av lågdosprotokollen för bukundersökningar i fall där patienten är överviktig och kan ibland inte appliceras alls om de patologiska fenomenen är för små. Överlag överväger fördelarna med lågdos CT dess nackdelar i de flesta fall. Slutsats: Resultatet har visat att lågdos CT kan uppnå samma diagnostiska säkerhet som CT undersökningar med standarddos. Vårdpersonal bör dock vara medveten om begränsningarna med lågdosprotokollen för att undvika risken för upprepning av undersökningar. Mer forskning kring ämnet kan potentiellt driva ner stråldosen ytterligare och med bättre kunskap bland personalen kan diagnoser ställas korrekt och risken för strålskador med CT kan minimeras.
235

Investigation and Development of a Fully 3D Tilt Capable Hybrid SPECT - CT System for Dedicated Breast Imaging

Shah, Jainil January 2015 (has links)
<p>X-ray mammography has been the gold standard for breast imaging for decades, despite the significant limitations posed by the two dimensional (2D) image acquisitions. Difficulty in diagnosing lesions close to the chest wall and axilla, high amount of structural overlap and patient discomfort due to compression are only some of these limitations. To overcome these drawbacks, three dimensional (3D) breast imaging modalities have been developed including dual modality single photon emission computed tomography (SPECT) and computed tomography (CT) systems. This thesis focuses on the development and integration of the next generation of such a device for dedicated breast imaging. The goals of this dissertation work are to: [1] understand and characterize any effects of fully 3-D trajectories on reconstructed image scatter correction, absorbed dose and Hounsifeld Unit accuracy, and [2] design, develop and implement the fully flexible, third generation hybrid SPECT-CT system capable of traversing complex 3D orbits about a pendant breast volume, without interference from the other. Such a system would overcome artifacts resulting from incompletely sampled divergent cone beam imaging schemes and allow imaging closer to the chest wall, which other systems currently under research and development elsewhere cannot achieve. </p><p>The dependence of x-ray scatter radiation on object shape, size, material composition and the CT acquisition trajectory, was investigated with a well-established beam stop array (BSA) scatter correction method. While the 2D scatter to primary ratio (SPR) was the main metric used to characterize total system scatter, a new metric called ‘normalized scatter contribution’ was developed to compare the results of scatter correction on 3D reconstructed volumes. Scatter estimation studies were undertaken with a sinusoidal saddle (±15° polar tilt) orbit and a traditional circular (AZOR) orbit. Clinical studies to acquire data for scatter correction were used to evaluate the 2D SPR on a small set of patients scanned with the AZOR orbit. Clinical SPR results showed clear dependence of scatter on breast composition and glandular tissue distribution, otherwise consistent with the overall phantom-based size and density measurements. Additionally, SPR dependence was also observed on the acquisition trajectory where 2D scatter increased with an increase in the polar tilt angle of the system. </p><p>The dose delivered by any imaging system is of primary importance from the patient’s point of view, and therefore trajectory related differences in the dose distribution in a target volume were evaluated. Monte Carlo simulations as well as physical measurements using radiochromic film were undertaken using saddle and AZOR orbits. Results illustrated that both orbits deliver comparable dose to the target volume, and only slightly differ in distribution within the volume. Simulations and measurements showed similar results, and all measured dose values were within the standard screening mammography-specific, 6 mGy dose limit, which is used as a benchmark for dose comparisons.</p><p>Hounsfield Units (HU) are used clinically in differentiating tissue types in a reconstructed CT image, and therefore the HU accuracy of a system is very important, especially when using non-traditional trajectories. Uniform phantoms filled with various uniform density fluids were used to investigate differences in HU accuracy between saddle and AZOR orbits. Results illustrate the considerably better performance of the saddle orbit, especially close to the chest and nipple region of what would clinically be a pedant breast volume. The AZOR orbit causes shading artifacts near the nipple, due to insufficient sampling, rendering a major portion of the scanned phantom unusable, whereas the saddle orbit performs exceptionally well and provides a tighter distribution of HU values in reconstructed volumes. </p><p>Finally, the third generation, fully-suspended SPECT-CT system was designed in and developed in our lab. A novel mechanical method using a linear motor was developed for tilting the CT system. A new x-ray source and a custom made 40 x 30 cm2 detector were integrated on to this system. The SPECT system was nested, in the center of the gantry, orthogonal to the CT source-detector pair. The SPECT system tilts on a goniometer, and the newly developed CT tilting mechanism allows ±15° maximum polar tilting of the CT system. The entire gantry is mounted on a rotation stage, allowing complex arbitrary trajectories for each system, without interference from the other, while having a common field of view. This hybrid system shows potential to be used clinically as a diagnostic tool for dedicated breast imaging.</p> / Dissertation
236

Head space: an exploration into architecture and neuroscience

Lamas, Mariana 06 August 2012 (has links)
The mental capacity for knowledge production, storage and dissemination is one of the characteristics that makes us human. Throughout history humankind has built spaces to accommodate knowledge in its various forms: from medieval monasteries to state-of-the-art research laboratories. The evolution of these ‘knowledge spaces’ and their architectural character can tell us a lot about a society´s views and perceptions of knowledge. Using monasteries, universities, libraries and research laboratories as examples of ‘knowledge spaces’ this essay aims to explore the relationship between knowledge and architecture throughout history in order to understand where knowledge has traditionally been produced, stored and disseminated. Drawing on this information, the appropriateness of the historical typologies will be assessed with regards to today´s context where the nature of knowledge is rapidly changing as a result of the emergence of new technologies
237

Ej-MR-villkorliga Hjärtimplantat : En litteraturstudie av dess risker och säkerhet i MR-miljö.

Omerovic, Muhamed, Feier, Ioan Räzvan January 2019 (has links)
Bakgrund: MRT som diagnostisk metod ökar konstant med åren och samtidigt ökar antalet patienter som får aktiva hjärtimplantat vilket leder till att undersökningar på patienter med ej-MR-villkorliga implantat också ökar. Undersökningarna utförs med olika protokoll och många faror finns när sådana undersökningar sker, många steg tas för att minimera riskerna för dessa patienter. Syfte: Sammanställa resultat av tidigare studier med avseende på säkerhetsaspekterna vid MR-undersökningar på patienter med ej-MR-villkorliga CIED. Metod: Studien är en kvantitativ litteraturstudie baserad på kvantitativa artiklar. Artiklarna hittades genom booleska sökmetoderna på PubMed för resultat samt snowballing för att samla in artiklar till bakgrunden och diskussionen. Resultat: MRT undersökningar på extremiteter såväl som huvud kan göras med minimala risker så länge de korrekta säkerhetsaspekterna följs. Undersökningar på det torakiska området var inte heller problematiskt, incidenser såsom Power-On-Reset var oftast under 1 %. Ingen incidens av dödsfall under MR undersökningarna på grund av implantaten i fråga. I vissa studier var batterierna problematiska och visade inte korrekt livslängd för implantatet efter MRT oftast med POR som möjlig orsak. Det är viktigt att all nödvändig personal är på plats eller tillgänglig under hela undersökningsprocessen fram tills patientens implantat har bekräftats fungera som normalt. Förändringar i ledarnas impedans dokumenterades i flera studier av oklar genes. Kvarlämnade- och brutna ledare visades sig vara relativt säkra. Artefakter var förekommande men var ej-kritiska, i några fall där FOV var i toraxregionen påverkades diagnosen. Slutsats: MRT av icke-torakiska undersökningar var säkra med säkerhetsprotokoll. / Background: MRI as a diagnostic method has increased with time, at the same time the number of patients with active heart implants has increased. This means we see an increasing number of MRI’s of patients with non-MR-conditional devices. The examinations are done with several different protocols and sequences, many dangers present themselves in these examinations therefore many steps are taken to minimize the risks to the patient during an MRI. Purpose: Compile results of earlier studies with regards to safety aspects during MRI of patients with non-MR-conditional CIED. Method: This is a quantitive literature study based on quantitative articles that were sourced using Boolean search methods on PubMed for the results and using the snowballing method for background and discussion. Results: MRI examinations on extremities as well as head-MRI can be done with minimal risks if the correct safety procedures are implemented. Thoracic examinations were quite safe with incidence rate of Power-on-Reset usually under 1%. No incidence of mortality during scanning due to CIED. In some studies, the batteries didn’t show their true remaining lifespan, usually preceded by a POR. All necessary personnel are to be in place during the exam or alternately available in a short timeframe during the entire examination until the examination is over and the patients CIED is determined to be working properly. Undetermined changes in lead impedance in several studies. Abandoned and broken leads showed no increased risk. Mild artefacts were documented, diagnostic imaging was only compromised when FOV was in the thorax region. Conclusion: Non-thoracic examinations were determined safe with safety protocol in place.
238

Röntgensjuksköterskans bemötande av barn med autismspektrumtillstånd : En litteraturstudie

Broke, Carolin, Norström, Ida January 2019 (has links)
Bakgrund: Barn som kommer till den radiologiska avdelningen kan uppleva oro i den högteknologiska miljön. Barn med autismspektrumtillstånd kan uppleva mer oro i dessa miljöer då diagnosen innebär nedsatta förmågor gällande social- och språklig kommunikation, föreställningsförmåga samt flexibilitet. För en optimal undersökning ställer det krav på att röntgensjuksköterskan kan ge ett bemötande som minskar oro. Metod/Syfte: Arbetet utformades som en litteraturöversikt med systematiskt tillvägagångssätt för att besvara syftet hur röntgensjuksköterskan kan bemöta barn med autismspektrumtillstånd för att minska oro i samband med undersökning på den radiologiska avdelningen. Resultat: Tre huvudkategorier identifierades i resultatet: vårdmiljö, vårdpersonalens roll samt föräldrarnas roll. För att minska oro hos barnet kan röntgensjuksköterskan anpassa vårdmiljön och genom förberedelser skapa en känd miljö. Röntgensjuksköterskan kan även ha ett förhållningssätt där kommunikation anpassas till barnet och ett samarbete med föräldrarna skapas.   Slutsats: Röntgensjuksköterskan har ansvar att anpassa sitt bemötande och kan genom att tillämpa strategier minska oro hos barnet med autismspektrumtillstånd vid radiologiska undersökningar.
239

Kartläggning av hjärnundersökningar med PET/CT på svenska universitetssjukhus : Redovisning av modalitetsuppbyggnad, undersökningsmetod och rekonstruktionsmetod samt stråldosjämförelse mellan PET och SPECT / Mapping of brain imaging with PET/CT in Swedish university hospitals : Presentation of modality structure, examination method and reconstruction method with a comparison of radiation dose between PET and SPECT

Keinan, Sara, Zaklan, Elma January 2019 (has links)
Positron emission tomography/computed tomography (PET/CT) is a method that quantitatively visualizes physiological processes. The most common indications for PET brain are early diagnosis of various dementia types with 18F-Fludeoxyglucose (18F-FDG). The hospital in Jonkoping installed a new PET/CT and brain examinations have not yet been performed. The aim of the study was to map how hospitals in Sweden performed seven selected brain examinations with PET/CT focusing on modality structure, examination method and reconstruction method, with a comparison of radiation dose between PET/CT and single photon emission computed tomography/CT (SPECT)/CT. Out of the nine university hospitals selected, two were excluded. The method was prospective with quantitative approach and data was collected through a protocol. Compilation was made on Excel and the statistics were processed using the Wilcoxon Signed Ranks Test. The result showed similarities, for example reconstruction method and differences, for example fasting time. Effective dose was higher on SPECT than PET in examination of Parkinson's disease, however no significant difference (p = 0,059) was detected. Higher effective doses on SPECT was due to longer half-lives and greater dosages of Ioflupane (123I-Datscan) than 18F-FDG. For further studies, more hospitals and parameters in the protocol can be included.
240

Improving Image Quality in Cardiac Computed Tomography using Deep Learning / Att förbättra bildkvalitet från datortomografier av hjärtat med djupinlärning

Wajngot, David January 2019 (has links)
Cardiovascular diseases are the largest mortality factor globally, and early diagnosis is essential for a proper medical response. Cardiac computed tomography can be used to acquire images for their diagnosis, but without radiation dose reduction the radiation emitted to the patient becomes a significant risk factor. By reducing the dose, the image quality is often compromised, and determining a diagnosis becomes difficult. This project proposes image quality enhancement with deep learning. A cycle-consistent generative adversarial neural network was fed low- and high-quality images with the purpose to learn to translate between them. By using a cycle-consistency cost it was possible to train the network without paired data. With this method, a low-quality image acquired from a computed tomography scan with dose reduction could be enhanced in post processing. The results were mixed but showed an increase of ventricular contrast and artifact mitigation. The technique comes with several problems that are yet to be solved, such as structure alterations, but it shows promise for continued development.

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