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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.
151

Naturliga kluster av funktionella enheter i ultraljudssekvenser : En utvärdering av klusteranalys för att detektera motoriska enheter i kontraherande skelettmuskulatur / Natural clusters of functional units in ultrasound sequences : An evaluation of cluster analysis for detection of motor units in contracting skeletal muscle tissue

Mårell Ohlsson, Adam January 2014 (has links)
Strukturell avbildning med ultraljud kan användas för att upptäcka sjukdomar och störningar i kroppen. För att ställa tillförlitliga diagnoser räcker det inte alltid med en strukturell avbildning utan ibland krävs det även fysiologisk information. Vid användning av funktionell avbildning med ultraljud kan den informationen mätas i kroppens olika fysiologiska system.   Systemen består av funktionellt olika enheter och kallas för motoriska enheter i skelettmuskulatur. Vid sjukdomar som ateroskleros (åderförkalkning) kan dessa enheter vara så kallade kärlplack, som består av vävnad med varierande egenskaper och medicinsk relevans. Möjligheten att kunna analysera funktionella enheter i system som dessa kan bidra mycket till diagnostisering av sjukdomar och störningar.   Den här studien presenterar en metod för att hitta naturliga kluster av funktionella enheter i skelettmuskulatur, från 3D-data inhämtat med ultraljudssekvenser.   I studien genererades syntetiska data från en modell som simulerar sekvenser av aktionspotentialer i kontraherande muskelvävnad. Datat bearbetades med förbehandlingar och klusteranalys och resultaten utvärderades med siluettkoefficienter. Kombinationer av fyra förbehandlingssätt och två klustringsalgoritmer jämförs i studien. Även tester på riktigt ultraljudsdata av muskelkontraktioner utfördes.   Den bästa kombinationen av förbehandling och klustringsalgoritm gav goda resultat och använder datanormalisering samt temporal bandpassfiltrering som förbehandling tillsammans med hierarkisk Complete Linkage-klustring. Den var dessutom relativt okänslig för störningar i datat. Resultaten från riktigt ultraljudsdata gav en grov indelning av områden i muskeln som visuellt överensstämmer med anatomin i den strukturella bilden. / Structural imaging using ultra sound can be used to detect diseases and disorders in the body. It’s not always enough to structurally image these detections for accurate diagnosis, sometimes physiologically functional information is needed. By using functional imaging, this information can be measured in various physiological systems throughout the body.   The systems are built up by functionally different units. In skeletal muscle these units are called motor units and in cases of disease, like atherosclerosis, they can be arterial plack. The placks have a tissue composition of various properties and clinical relevance. If functional units could be analyzed in systems like these, much could be contributed to diagnosis of diseases and disorders.   In this study, a method of detecting natural clusters of functional units in skeletal muscle, using 3D data collected from ultrasound sequences, is presented.   Using a model that simulates a series of actions potentials in contracting muscle tissue, synthetic data was generated. During analysis the data was preprocessed and clustered, the results were analyzed using silhouette coefficients. In this study, combinations of four methods of preprocessing and two clustering algorithms are compared. Real ultrasound data of contracting muscle tissue was also examined.   A combination of preprocessing and clustering that clustered the data particularly well used data normalization and temporal passband filtering for preprocessing together with hierarchical Complete Linkage clustering. It also seemed to be relatively unaffected by noise. Clustering of the real ultrasound data resulted in a coarse sorting of the different areas of the muscle that corresponds to the anatomy seen in structural images.
152

Guidelines for smartphone usage in telemedical photography / Riktlinjer för användning av smartphones inom telemedicinsk fotografering

Hagman, Anna, Riedberg, Sander January 2014 (has links)
The wide usage of smartphones makes them an interesting and potential medical device. Given that smartphone cameras have a sufficiently high quality - some of the medical photography done at health care facilities could be done telemedically and by non-medically educated per- sons. Therefore a research of the quality of the photos taken with smartphone cameras has been done. This thesis presents guidelines regarding how inexperienced persons could take high qualitative medical photos with a smartphone. This thesis includes a review of current guidelines within medical photography. A compari- son between two popular smartphones and a professional medical camera has been done - where possibilities and limitations in smartphone cameras have been identified. In order to evaluate the sharpness and the color temperature representation in the photos taken with smartphones, an experiment with realistic lighting and easy accessible color-calibration cards has been done. The execution and the achieved result have formed the basis of the proposed guidelines. The result shows that smartphone cameras are of high quality and thereby could be used as a complement to advanced medical camera equipment. With the help of the proposed guidelines inexperienced persons could acquire sufficiently good medical photos, in order to be used as diagnostic material. This thesis provides a foundation for further research and implementation within the area, with the purpose of becoming an important part of the efficiency improvement within the telemedical health care.
153

Karolinska Testbädd för Telemedicin och eHälsa : En analys av medicintekniska företags behov och krav på en samverkansmiljö för produktutveckling på Karolinska Universitetssjukhuset

Björkehag, Jonathan, Seglare, Kristin January 2010 (has links)
Syftet med uppsatsen är att kartlägga behovet av en testbädd för telemedicinska produkter och att analysera krav som medicintekniska företag ställer på en testbäddsmiljö för samverkan med sjukvården. Målet har varit att konkretisera resultatet i en kommersialiseringsplan för Karolinska Testbädd för Telemedicin och eHälsa, vid Medicinsk Teknik på Karolinska Universitetssjukhuset. Vid genomförandet av undersökningen har totalt 19 intervjuer och ytterligare 6 telefonintervjuer genomförts med dels representanter från medicintekniska företag och sjukvården och dels med samarbetsstrukturer för medicinsk teknik och möjliga finansiärer. En enkätundersökning har genomförts för att kvantifiera resultatet från intervjuerna. Webbutskick har gjorts till 279 företag med verksamhet inom områdena medicinsk teknik, IT och telekom. Uppsatsen beskriver hur den kliniska forskningen inom området medicinsk teknik har förändrats de senaste decennierna och hur situationen ser ut idag. Utmaningar som den svenska hälso- och sjukvården står inför presenteras, som demografiska förändringar, ökade sjukvårdskostnader, dyrare behandlingsmetoder och färre kommersialiserade innovationer inom medicinsk teknik.  Omständigheter som påverkar produktutveckling för hälso- och sjukvården belyses, dels genom den regulatoriska gränsdragningen mellan IT-produkter och medicintekniska produkter och dels utifrån en genomgång av forskning inom produkt- och tjänsteutveckling och utifrån de frågor kring hur företag bedriver produktutveckling som ställts i intervjuerna och i webbenkäten. Resultatet visar att företagen i högsta grad är beroende av samarbete med sjukvården i olika faser av sin produktutvecklingsprocess och att flera företag uttrycker ett behov av en testbäddsstruktur. Företagen samarbetar med vården framförallt för att det möjliggör att utveckla mer vårdanpassade produkter. Samarbete med vården ger kortare utvecklingstider och därmed minskade utvecklingskostnader. Det förenklar även arbetet med validering av produkters funktionalitet. Flera företag har utarbetade samarbeten direkt in på vårdavdelningar, medan andra i dagsläget saknar nödvändiga samarbetsstrukturer. Studien har identifierat ett flertal företag som visat intresse för ett samarbete med Testbädden och ytterligare ett antal som har önskat att få mer information om vad Testbädden kan erbjuda. I kommersialiseringsplanen föreslås Karolinska Testbädd för Telemedicin och eHälsa fokusera på sin nisch samt vidareutveckla den kompetens som företagen saknar. Testbädden bör arbeta vidare med att utveckla både externa kontakter och den interna samverkansorganisationen på Karolinska för att möjliggöra effektiva, smidiga och kvalitativa samarbeten mellan företag och sjukhusets avdelningar. / The purpose is to study the demand for a testbed for telemedicine and to analyze the medical device-developing companies’ requirements on the testbed’s facilities when collaborating with the healthcare sector in their product development. The study’s aim is to result in a commercialization plan for Karolinska Testbed for telemedicine and eHealth, at the department of Biomedical Engineering at Karolinska University Hospital. During the study, 19 interviews and 6 telephone-interviews has been held with people from the medical device industry, hospitals, potential funders and collaboration structures which foster medical device development. A web-survey has been sent to 279 companies within the fields of medical technologies, IT and telecom, to quantify the results from the interviews. The study describes how the clinical research on medical technologies has changed over the last decades and what the situation is like today. Present and forthcoming challenges to the Swedish health care system is presented, like demographic changes, increasing healthcare-costs, expensive treatments and the scarcity of medical device innovations being commercialized. Obstacles affecting the medical device development are studied, including the regulatory differences between IT and medical devices. An analysis of the research on product and service development is also looked at from the perspectives on how the medical device companies develop their products, which is derived from both interviews and the web-survey. The result shows that medical device companies rely upon the ability to collaborate with the hospitals in different phases of their product development process and that there is an extensive need for a testbed structure amongst companies. The companies that collaborate with hospitals do it primarily because it makes their products more adaptive to functioning in the settings of healthcare, time to market and development costs can be decreased and it facilitates the process when validating the functionality of their products. Several companies have their ways of collaborating with hospital wards whilst others explicitly lack indispensable collaboration structures. The study has identified some companies which have shown interest in collaborating with Testbed Karolinska for telemedicine and eHealth and other ones whom wish to receive more information on what the testbed can offer them. In the commercialization plan it is suggested that Karolinska Testbed for telemedicine and eHealth shall focus on their niche and elaborate the competency which the companies doesn’t have. It is also suggested that the Testbed continues the work with developing the internal organization within Karolinska to enable efficient, flexible and qualitative collaboration between companies and the clinics at Karolinska University Hospital.
154

Mobilt bredband till mobil röntgen : Förbättring av Region Skånes pilotprojekt med mobil röntgenverksamhet

Toivanen, Tommi January 2012 (has links)
Detta arbete beskriver en examensuppsats i datateknik på Linnéuniversitetet. Röntgenavdelningen på SUS, Skånes Universitetssjukhus i Lund, använder en lättviktig flyttbar röntgenmaskin som väger endast cirka 90 kg, för röntgenundersökningar ute på äldreboenden. Bilderna överförs till sjukhusets PACS när maskinen är tillbaka på sjukhuset, genom att man kopplar in Dragon via kabel till sjukhusets nätverk. Målsättningen är att förbättra den trådlösa kommunikationen som för närvarande är för långsam och opålitlig, så att bilderna kan överföras till sjukhusets PACS direkt efter undersökningen. I detta arbete beskrivs vilka alternativ som kan användas. Samt om de mobila bredbandstjänster som finns tillgängliga i Region Skåne är bra nog för att kunna användas för uppgiften. Slutsatsen är att ett 3G HSDPA/HSUPA abonnemang kan vara tillförlitligt nog. Framför allt om extra redundans tillförs med dubbla SIM-kort som använder separata nät och att signalen förstärks med antenn placerad utomhus på transportfordonet. Transportfordonet används som brygga mellan Wifi och mobilt nätverk. Röntgenmaskinen kommunicerar med transportfordonet via Wifi. För de fall Wifi inte fungerar på grund av byggnader och omgivande miljö arbetades ett reservalternativ fram. Jag har också undersökt och jämfört DICOM protokollet mot FTP. Detta för att se om DICOM har en overhead som skulle motivera användet av FTP istället för sändning av bilder. Resultatet av jämförelsen visade att DICOM har 5-10 % overhead jämfört med FTP. / This abstract describes a degree project in computer engineering at Linnaeus University. The Department of Radiology at SUS, Skåne University Hospital in Lund, is using a lightweight portable x-ray machine that weights about 90 kg, for radiography services in nursing homes for elders. The images are transferred to hospital PACS when the machine returns to the hospital, this is done with Dragon connecting to hospital network via wire. The goal is to improve the currently too slow and unreliable wireless communication, so the images can be transferred to hospital PACS directly after examination. This report describes what alternatives can be used and investigates whether the mobile broadband services currently available in Skåne County are good enough to be relied on for the task. The conclusion is that a 3G HSDPA/HSUPA subscription can be used reliably enough, if extra redundancy is added via dual SIM cards using separate mobile networks and the signal is strengthen by an antenna placed outdoors on the transport vehicle. The transport vehicle is used as a bridge between Wifi and mobile networks. The mobile x-ray machine communicates with the transport vehicle via Wifi. In those cases Wifi does not work due to difficult building environments, a backup solution was worked out to be used. I also investigated and compared the DICOM protocol against FTP. This was to find out if DICOM has an overhead that would motivate using FTP instead for the transmission of the images, the result of the comparison showed that DICOM has an 5-10 % overhead compared with FTP. / Mobil röntgen Skånes Universitetssjukhus Lund
155

Att bädda för test : Utvecklingen av en innovations- och testmiljö inom Landstinget i Östergötland / Making the bed for testing : The development of an innovation and testing environment within the County Council of Östergötland

Nilsson, Frida, Savelid, Christin January 2013 (has links)
Ämnet för uppsatsen grundar sig i en ökad efterfrågan av att kunna införa teknik och informationsteknik (IT), som är testad och anpassad för en verksamhet redan innan införandet. Vidare finns det ett behov av att, genom nya innovationer, uppnå långsiktiga strategiska mål inom vård och omsorg. Därför har Sveriges innovationsmyndighet Vinnova startat en satsning på testbäddar inom vård och omsorg. En testbädd kan liknas vid en innovations- och testmiljö där samarbete mellan vårdpersonal, företag och forskning kan ske för att ta fram produkter, processer och tjänster som är anpassade till den miljö där dessa sedan ska tillämpas. Denna studie berör hur utveckling och organisering av en innovations- och testmiljö kan gå till och vilka utmaningar som finns. Vidare tar vi upp intressenters roller och behov i utvecklingen samt hur innovation kan stimuleras i en organisation. Detta har genomförts med hjälp av en fallstudie kring utvecklingen av en testbädd i Landstinget i Östergötland (LIÖ). Teorier inom områdena intressenter, utveckling och innovation används för att stödja analysen och skapa förståelse för vissa begrepp. Den empiriska undersökningen utförs genom semistrukturerade intervjuer med representanter från olika intressentgrupper till testbädd LIÖ. Analysen genomförs även med hjälp av dokumentstudier som en del i den empiriska undersökningen. Det empiriska materialet diskuteras i relation till den teoretiska referensramen för att uppnå ett kunskapsbidrag i form av en slutsats. Denna berör hur en innovations- och testmiljö kan utvecklas och organiseras, intressenternas roll och behov i utvecklingen samt hur innovationer kan genereras och utvecklas i organisationer. Med fallets hjälp kan praktiken ge ny kunskap om dessa områden inför kommande utvecklingsprojekt av liknande karaktär. / The topic of this paper is based on an increased demand for the introduction of technology and information technology (IT), which is better tested and adapted for a business before the implementation. Furthermore, there is a need that through new innovations, achieve long-term strategic objectives in the care sector. Therefore, the Swedish innovation agency Vinnova started a venture in test beds in healthcare. A test bed can be likened to an innovation and testing environment. In these, collaboration between healthcare professionals, businesses and research is done to develop products, processes and services that are adapted to the environment in which they are then applied. This study concerns the development and organization of an innovation- and testing environment and what the challenges are. It also concerns the roles and the needs of the stakeholders in the development and how innovation can be achieved in an organization. This has been studied by a case concerning the development of the testbed LIÖ in Östergötland County Council. Theories in the fields of stakeholders, development and innovation are used to support the analysis around these parts, and to create an understanding of some concepts. The empirical study is carried out through semi-structured interviews with representatives from various stakeholder groups to testbed LIÖ. The analysis is also carried out with the help of document studies as part of the empirical investigation. The empirical data are discussed in relation to the theoretical framework for achieving a knowledge contribution in the form of a conclusion. This affects how an innovation and test environment can be developed and organized, stakeholder roles and needs of the development and how innovations can be generated and developed in organizations. The study of the case can provide new knowledge in these areas for future development projects of similar nature.
156

Upphandling av medicintekniska produkter inom sjukvården i Sverige / Public procurement of medical devices in Swedish healthcare

Andersson, Elin, Filipsson, Emma January 2017 (has links)
Since 1994, the Public Procurement Act has undergone changes aimed to improve the procurement process and promoting innovation. In order to promote innovation there are a number of government agencies that offer financial assistance, especially to small business with innovative ideas. Despite these efforts, newly established small businesses have difficulties entering the market. The study investigates whether changes have been made in the public procurement of medical devices with regard to price and quality prioritization. The priority criteria is presented by the contracting authority as percentage in the allocation criteria. The study is limited to in vitro diagnostic products contracting in Swedish healthcare between the years 2009 and 2015. All tenders, companies that apply for participation in procurement, were analyzed based on sales, number of employees and year of establishment with the purpose of evaluating differences between winning tenders and other tenders. The result shows that prioritization has been increasingly on price rather than the quality. Regarding the winning tenders the study shows that larger, more established companies dominates the market. Noteworthy is that this dominance has increased over theses last years. The increase may be due to a spiral effect that is created when winning tenders get an increased economic power.
157

Incitament för centraliserad hantering av externa serviceavtal / Incentive for Centralized Management of External Service Agreements

Björling Nordström, Sebastian, Pruul Trueman, Eric January 2018 (has links)
At the moment there are no guidelines to how external service agreements should be managed and administered at Södersjukhuset. The goal with this report has been to provide Södersjukhuset with supporting arguments to decide if they should centralize the management of service agreements or not. In order to achieve this goal it was essential to: study and get a better understanding of the term centralization, examine the serviceagreements’ to get a greater awareness of their extent and analyze Södersjukhuset to gain a better insight of the organisation as a whole. Service agreements were accumulated throughmeetings with the hospital’s employees and through the software Medusa. Calculations were conducted from the agreements to display Södersjukhuset’s current situation. Themanagement of the hospital’s service agreements was considered decentralized and wasdeemed to convey negative economical factors. A proposed solution for the problem was a centralized structure for managing external service agreements which would help the hospital organize and benefit it economically. / Det finns idag ingen struktur för hur externa serviceavtal ska hanteras och förvaltas på Södersjukhuset. Målet med denna rapport har varit att bistå Södersjukhuset med underlag för att avgöra om de ekonomiskt sett bör centralisera sina serviceavtal eller ej. För att uppnå detta studerades: begreppet centralisering, serviceavtalens omfattning samt Södersjukhuset i form av organisation och dess resurser. Insamling av avtal verkställdes genom möten med personal på Södersjukhuset och via mjukvaran Medusa. Från avtalen upprättades kalkyler för att beskriva hur situationen med avtalen såg ut. SÖS bedömdes vara decentraliserat vid hanteringen av externa serviceavtal vilket ansågs vara en ekonomisk nackdel. Rekommendation för att åtgärda dessa problem var att upprätta en centraliserad struktur som stödjer en organiserad hantering av externa serviceavtal och bidrar till en ekonomisk nytta för Södersjukhuset.
158

Tyst kunskap och produktdatasystem vid medicinteknisk tillverkning : Pilotstudie av system för produktdatahantering och kartläggning av den tysta kunskapen vid Nationellt respirationscetrum, NRC / Tacit knowledge and product data management system in medical technology production : Pilot study of a PDM system and survey of the tacit knowledge at National respiratory centre, NRC

Hedlund, Niclas January 2009 (has links)
<p>This thesis looks at two sides of the same coin: how to support the production and future development at a specialist medical technology department at Danderyd Hospital. The two sides are; a pilot study of a product management system (PDM) and an interview based study on the characteristics of the silent knowledge of the technicians. The department (National respiratory centre, NRC) is facing retirement of several key employees.</p><p>The technical study shows that the success of an implementation is largely dependent on the users’ prior knowledge and use of a 3D Computer aided design system (CAD).The system itself is shown to fulfill the Lifecycle requirement of tracking the products (mostly tracheostomy tubes) but without a CAD centered workflow, some substantial education and preferably some new recruits, an implementation of the PDM system will fail. The author recommends development of the current “low-tech” system of MS Excel and Access rather than redistribute the dependency from technician towards a complex, commercial software and its vendor.</p><p>The analysis of the technicians’ silent knowledge with the newly developed method, epithet for silent knowledge (ETK), shows that the longer employment time:</p><ul><li>the more differentiated technicians become in describing their work,</li><li>practical knowledge are regarded higher and</li><li>the social and collective problem solving factors of the work becomes more important.</li></ul><p>Typically, it is shown that a new employee should preferably enjoy problem solving, being pragmatic and social as well as having some prior education or work experience in a CAD and/or a PDM system.</p>
159

Extracellular Matrix Based Materials for Tissue Engineering

Aulin, Cecilia January 2010 (has links)
The extracellular matrix is (ECM) is a network of large, structural proteins and polysaccharides, important for cellular behavior, tissue development and maintenance. Present thesis describes work exploring ECM as scaffolds for tissue engineering by manipulating cells cultured in vitro or by influencing ECM expression in vivo. By culturing cells on polymer meshes under dynamic culture conditions, deposition of a complex ECM could be achieved, but with low yields. Since the major part of synthesized ECM diffused into the medium the rate limiting step of deposition was investigated. This quantitative analysis showed that the real rate limiting factor is the low proportion of new proteins which are deposited as functional ECM. It is suggested that cells are pre-embedded in for example collagen gels to increase the steric retention and hence functional deposition. The possibility to induce endogenous ECM formation and tissue regeneration by implantation of growth factors in a carrier material was investigated. Bone morphogenetic protein-2 (BMP-2) is a growth factor known to be involved in growth and differentiation of bone and cartilage tissue. The BMP-2 processing and secretion was examined in two cell systems representing endochondral (chondrocytes) and intramembranous (mesenchymal stem cells) bone formation. It was discovered that chondrocytes are more efficient in producing BMP-2 compared to MSC. The role of the antagonist noggin was also investigated and was found to affect the stability of BMP-2 and modulate its effect. Finally, an injectable gel of the ECM component hyaluronan has been evaluated as delivery vehicle in cartilage regeneration. The hyaluronan hydrogel system showed promising results as a versatile biomaterial for cartilage regeneration, could easily be placed intraarticulary and can be used for both cell based and cell free therapies.
160

Spectral Mammography with X-Ray Optics and a Photon-Counting Detector

Fredenberg, Erik January 2009 (has links)
Early detection is vital to successfully treating breast cancer, and mammography screening is the most efficient and wide-spread method to reach this goal. Imaging low-contrast targets, while minimizing the radiation exposure to a large population is, however, a major challenge. Optimizing the image quality per unit radiation dose is therefore essential. In this thesis, two optimization schemes with respect to x-ray photon energy have been investigated: filtering the incident spectrum with refractive x-ray optics (spectral shaping), and utilizing the transmitted spectrum with energy-resolved photon-counting detectors (spectral imaging). Two types of x-ray lenses were experimentally characterized, and modeled using ray tracing, field propagation, and geometrical optics. Spectral shaping reduced dose approximately 20% compared to an absorption-filtered reference system with the same signal-to-noise ratio, scan time, and spatial resolution. In addition, a focusing pre-object collimator based on the same type of optics reduced divergence of the radiation and improved photon economy by about 50%. A photon-counting silicon detector was investigated in terms of energy resolution and its feasibility for spectral imaging. Contrast-enhanced tumor imaging with a system based on the detector was characterized and optimized with a model that took anatomical noise into account. Improvement in an ideal-observer detectability index by a factor of 2 to 8 over that obtained by conventional absorption imaging was found for different levels of anatomical noise and breast density. Increased conspicuity was confirmed by experiment. Further, the model was extended to include imaging of unenhanced lesions. Detectability of microcalcifications increased no more than a few percent, whereas the ability to detect large tumors might improve on the order of 50% despite the low attenuation difference between glandular and cancerous tissue. It is clear that inclusion of anatomical noise and imaging task in spectral optimization may yield completely different results than an analysis based solely on quantum noise. / QC 20100714

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