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Aplicação do transdutor magnetoacústico em estudos gástricos: in vitro e in vivo / Magnetoacústico transducer application in gastric studies: in vitro and in vivo.Bruno, Alexandre Colello 23 January 2015 (has links)
A proposta deste trabalho foi desenvolver e avaliar as aplicações do transdutor magnetoacústico, em estudos in vitro e in vivo como ferramenta para o diagnóstico clínico, inicialmente para a análise de motilidade gastrintestinal. Na primeira etapa, a intensidade do campo magnético foi mapeada e ajustada, o melhor processamento para os dados foi definido e a viabilidade do uso de nanopartículas como marcadores foi contatada. Nos estudos in vivo, realizados em ratos, avaliou-se o potencial do transdutor híbrido para análise do esvaziamento gástrico, de alimentos marcado com partículas magnéticas, comparando os dados susceptométricos (padrão ouro) com os acústicos. O esvaziamento foi relacionado com a variação de área do estômago no tempo, que foi demarcada nas imagens de ultrassom usando a vibração das partículas como contraste. Outras variações e aplicações da ultrassonografia magnetomotriz foram investigadas, usando a excitação magnética pulsada (antes harmônica), aumentando a taxa de aquisição das imagens e gerando imagens elastográficas em fantomas. A produção e detecção de Shaer Waves (elastografia absoluta) também foi avaliada em outros fantomas com uma esfera de ferrita, sem e com uma inclusão mais rígida. A ultrassonografia magnetomotriz pulsada e o processamento vinculado a ela foram capazes de gerar as shear waves, através de puxões magnéticos na esfera de ferrita, e estimar a velocidade de propagação dessas. Com esta velocidade, estimaram-se os coeficientes elástico e viscoso dos meios de propagação. Portanto, o transdutor magnetoacústico, avaliado de diversas formas nesse trabalho, apresentou-se como uma potencial ferramenta para diagnóstico da motilidade gástrica in vivo, usando tanto a ultrassonografia magnetomotriz harmônica como a pulsada. As técnicas de processamento podem ser convencionais (modos Doppler, Power Doppler e elastográficos) ou dedicadas, as quais podem detectar deslocamentos, deformações ou propagação de ondas sísmicas; suas aplicações não se limitam ao estômago e nem os diagnósticos in vivo. / The aim of this study was to develop and to evaluate applications magneto-acoustic transducer in phantoms and in vivo studies, as a tool for clinical diagnosis, initially for analysis of gastrointestinal motility. First step, the magnetic field intensity was adjusted and mapped; the best data and image processing was defined, and nanoparticles markers were studied to future applications. In experiments with rats (in vivo), we evaluated the hybrid transducer potential by gastric emptying analysis using foods labeled magnetic particles, comparing the susceptometric data (gold standard) with the acoustic. Others magneto motive ultrasonography variations and applications were investigated. The variations were the pulsed magnetic excitation and the high frame rate. The rats empty gastric were evaluated with solid and liquid food by pulsed magneto-motive ultrasound; the solid food took longer to leave the stomach, as was expected. Other applications based on the use of elastography techniques combined with pulsed magneto-motive ultrasound in phantoms were evaluated - the first potential application was the lesions detection in the colon wall (by elastography relative). In this case, harder inclusions were located by elastography based on deformations caused by the magnetic pulse and by the magnetic fluid inserted in the supposed colon. The second potential application was Shear Waves production and detection (Transient elastography) using a ferrite sphere inside the phantoms with a harder inclusion. The pulsed Magneto Motive Ultrasound was able to generate shear waves by magnetic \"pushes\" in the ferrite sphere and it estimated the speed propagation of these. Therefore, the Magneto-Acoustic transducer showed that it is a potential tool for gastric motility diagnosis in vivo, using the harmonic or pulsed Magneto-Motive Ultrasound. Their processing techniques can be conventional (Doppler, Power Doppler and elastography modes), or dedicated to detect displacements, strains and seismic waves propagation, and its applications are not limited to stomach and in vivo diagnostics.
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Aplicação do transdutor magnetoacústico em estudos gástricos: in vitro e in vivo / Magnetoacústico transducer application in gastric studies: in vitro and in vivo.Alexandre Colello Bruno 23 January 2015 (has links)
A proposta deste trabalho foi desenvolver e avaliar as aplicações do transdutor magnetoacústico, em estudos in vitro e in vivo como ferramenta para o diagnóstico clínico, inicialmente para a análise de motilidade gastrintestinal. Na primeira etapa, a intensidade do campo magnético foi mapeada e ajustada, o melhor processamento para os dados foi definido e a viabilidade do uso de nanopartículas como marcadores foi contatada. Nos estudos in vivo, realizados em ratos, avaliou-se o potencial do transdutor híbrido para análise do esvaziamento gástrico, de alimentos marcado com partículas magnéticas, comparando os dados susceptométricos (padrão ouro) com os acústicos. O esvaziamento foi relacionado com a variação de área do estômago no tempo, que foi demarcada nas imagens de ultrassom usando a vibração das partículas como contraste. Outras variações e aplicações da ultrassonografia magnetomotriz foram investigadas, usando a excitação magnética pulsada (antes harmônica), aumentando a taxa de aquisição das imagens e gerando imagens elastográficas em fantomas. A produção e detecção de Shaer Waves (elastografia absoluta) também foi avaliada em outros fantomas com uma esfera de ferrita, sem e com uma inclusão mais rígida. A ultrassonografia magnetomotriz pulsada e o processamento vinculado a ela foram capazes de gerar as shear waves, através de puxões magnéticos na esfera de ferrita, e estimar a velocidade de propagação dessas. Com esta velocidade, estimaram-se os coeficientes elástico e viscoso dos meios de propagação. Portanto, o transdutor magnetoacústico, avaliado de diversas formas nesse trabalho, apresentou-se como uma potencial ferramenta para diagnóstico da motilidade gástrica in vivo, usando tanto a ultrassonografia magnetomotriz harmônica como a pulsada. As técnicas de processamento podem ser convencionais (modos Doppler, Power Doppler e elastográficos) ou dedicadas, as quais podem detectar deslocamentos, deformações ou propagação de ondas sísmicas; suas aplicações não se limitam ao estômago e nem os diagnósticos in vivo. / The aim of this study was to develop and to evaluate applications magneto-acoustic transducer in phantoms and in vivo studies, as a tool for clinical diagnosis, initially for analysis of gastrointestinal motility. First step, the magnetic field intensity was adjusted and mapped; the best data and image processing was defined, and nanoparticles markers were studied to future applications. In experiments with rats (in vivo), we evaluated the hybrid transducer potential by gastric emptying analysis using foods labeled magnetic particles, comparing the susceptometric data (gold standard) with the acoustic. Others magneto motive ultrasonography variations and applications were investigated. The variations were the pulsed magnetic excitation and the high frame rate. The rats empty gastric were evaluated with solid and liquid food by pulsed magneto-motive ultrasound; the solid food took longer to leave the stomach, as was expected. Other applications based on the use of elastography techniques combined with pulsed magneto-motive ultrasound in phantoms were evaluated - the first potential application was the lesions detection in the colon wall (by elastography relative). In this case, harder inclusions were located by elastography based on deformations caused by the magnetic pulse and by the magnetic fluid inserted in the supposed colon. The second potential application was Shear Waves production and detection (Transient elastography) using a ferrite sphere inside the phantoms with a harder inclusion. The pulsed Magneto Motive Ultrasound was able to generate shear waves by magnetic \"pushes\" in the ferrite sphere and it estimated the speed propagation of these. Therefore, the Magneto-Acoustic transducer showed that it is a potential tool for gastric motility diagnosis in vivo, using the harmonic or pulsed Magneto-Motive Ultrasound. Their processing techniques can be conventional (Doppler, Power Doppler and elastography modes), or dedicated to detect displacements, strains and seismic waves propagation, and its applications are not limited to stomach and in vivo diagnostics.
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Analyzing the Benefits and Downsides of Mobile Mammography Units in Sweden / Analysera fördelarna och nackdelarna med mobila mammografienheter i SverigeMasoom, Sadia January 2022 (has links)
Breast Cancer is the second most common cancer in Sweden. More treatment options are available with a higher chance of survival if Breast cancer is diagnosed early. WHO has recommended performing Breast Cancer screenings on women even before they develop any symptoms. In Sweden, all women between the age of 40 and 74 years are called for a Breast Cancer Screening examination every two years. However, all of the called out women are not appearing for Breast screening therefore the purpose of this degree project is to analyze the possible benefits of setting up Mobile Mammography Units (MMUs) in Sweden. This thesis focuses on need-analysis, cost-analysis, image quality, and quality of care in MMUs compared to fixed units and if MMUs can be used as a tool for dispersal of knowledge regarding preventive care for cancer. Further, long waiting queues is one of the major concern and underperformed area in Sweden. Since the enactment of Cancer Care Pathways in Sweden, long waiting queues for patients having non-cancer diseases have been the most frequently mentioned risk in the regional status reports. This study, therefore, aims to analyze if mammography screening in hospitals is adding up to the long waiting ques for other patients or not. This study followed a qualitative setting where several semi-structured interviews were conducted with members of the National workgroup of mammography in Sweden, and an abductive inductive approach was followed for the data collection and analysis. The results of the study concluded that Mobile mammography units are only beneficial for areas with demographic issues. Mobile mammography units are resource-demanding therefore it is better to invest in fixed units for areas where there are no traveling issues. The mammography unit in a hospital is a separate department and does not affect any other patient by being in the hospital hence not resulting in the “Crowding out effect”. Regarding the Image quality and quality of care, it is similar in both the fixed and mobile units, apart from the quality of care for disabled women who must visit the fixed unit and hence are deprived of close care. A proper cost-analysis, with exact figures, for both mobile and fixed mammography units was not found during this study therefore it could not be concluded if MMUs are cost-effective or not. Also, if Mobile Mammography Units are to be used as a tool for the dispersal of knowledge regarding the prevention of cancer, there will be a need to hire extra staff who can perform this job. / Bröstcancer är den näst vanligaste cancerformen i Sverige. Fler behandlingsalternativ finns tillgängliga med högre chans att överleva om bröstcancer diagnostiseras tidigt. WHO har rekommenderat att utföra bröstcancerscreeningar på kvinnor även innan de utvecklar några symtom. I Sverige kallas alla kvinnor mellan 40 och 74 år till en bröstcancerundersökning vartannat år. Alla kvinnor som bjuds in till undersökning dyker dock inte upp, därför är syftet med detta examensarbete att analysera möjliga fördelar med att sätta upp mobila mammografienheter (MMU) i Sverige. Långa väntetider är ett stort problem i Sverige, även för dessa patienter som inte har cancer eller tecken på cancer. Denna studie syftar därför till att analysera om mammografiscreening på sjukhus ökar eller minskar de långa väntetiderna för andra patienter som inte är drabbade av cancern. Resultat av studien visar att mobila mammografienheter endast är fördelaktiga för områden med demografiska problem. Mobila mammografienheter är resurskrävande, därför är det bättre att investera i fasta enheter för områden där det inte finns några reseproblem. Också Mammografienheten på ett sjukhus är en separat avdelning och bör inte påverka antal mängder patienter på ett sjukhus. Vi kunde inte fastställa kostnader för vare sig mobila eller fasta mammografienheter under denna studie. Därmed kan slutsatsen inte avgöras om det är förmånligt med mobila mammografienheter eller inte. Men däremot är en sak säker, det kommer att behövas att anställa fler personal.
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