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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.
31

Interfaces for Modular Surgical Planning and Assistance Systems

Gessat, Michael 22 June 2010 (has links)
Modern surgery of the 21st century relies in many aspects on computers or, in a wider sense, digital data processing. Department administration, OR scheduling, billing, and - with increasing pervasion - patient data management are performed with the aid of so called Surgical Information Systems (SIS) or, more general, Hospital Information Systems (HIS). Computer Assisted Surgery (CAS) summarizes techniques which assist a surgeon in the preparation and conduction of surgical interventions. Today still predominantly based on radiology images, these techniques include the preoperative determination of an optimal surgical strategy and intraoperative systems which aim at increasing the accuracy of surgical manipulations. CAS is a relatively young field of computer science. One of the unsolved "teething troubles" of CAS is the absence of technical standards for the interconnectivity of CAS system. Current CAS systems are usually "islands of information" with no connection to other devices within the operating room or hospital-wide information systems. Several workshop reports and individual publications point out that this situation leads to ergonomic, logistic, and economic limitations in hospital work. Perioperative processes are prolonged by the manual installation and configuration of an increasing amount of technical devices. Intraoperatively, a large amount of the surgeons'' attention is absorbed by the requirement to monitor and operate systems. The need for open infrastructures which enable the integration of CAS devices from different vendors in order to exchange information as well as commands among these devices through a network has been identified by numerous experts with backgrounds in medicine as well as engineering. This thesis contains two approaches to the integration of CAS systems: - For perioperative data exchange, the specification of new data structures as an amendment to the existing DICOM standard for radiology image management is presented. The extension of DICOM towards surgical application allows for the seamless integration of surgical planning and reporting systems into DICOM-based Picture Archiving and Communication Systems (PACS) as they are installed in most hospitals for the exchange and long-term archival of patient images and image-related patient data. - For the integration of intraoperatively used CAS devices, such as, e.g., navigation systems, video image sources, or biosensors, the concept of a surgical middleware is presented. A c++ class library, the TiCoLi, is presented which facilitates the configuration of ad-hoc networks among the modules of a distributed CAS system as well as the exchange of data streams, singular data objects, and commands between these modules. The TiCoLi is the first software library for a surgical field of application to implement all of these services. To demonstrate the suitability of the presented specifications and their implementation, two modular CAS applications are presented which utilize the proposed DICOM extensions for perioperative exchange of surgical planning data as well as the TiCoLi for establishing an intraoperative network of autonomous, yet not independent, CAS modules. / Die moderne Hochleistungschirurgie des 21. Jahrhunderts ist auf vielerlei Weise abhängig von Computern oder, im weiteren Sinne, der digitalen Datenverarbeitung. Administrative Abläufe, wie die Erstellung von Nutzungsplänen für die verfügbaren technischen, räumlichen und personellen Ressourcen, die Rechnungsstellung und - in zunehmendem Maße - die Verwaltung und Archivierung von Patientendaten werden mit Hilfe von digitalen Informationssystemen rationell und effizient durchgeführt. Innerhalb der Krankenhausinformationssysteme (KIS, oder englisch HIS) stehen für die speziellen Bedürfnisse der einzelnen Fachabteilungen oft spezifische Informationssysteme zur Verfügung. Chirurgieinformationssysteme (CIS, oder englisch SIS) decken hierbei vor allen Dingen die Bereiche Operationsplanung sowie Materialwirtschaft für spezifisch chirurgische Verbrauchsmaterialien ab. Während die genannten HIS und SIS vornehmlich der Optimierung administrativer Aufgaben dienen, stehen die Systeme der Computerassistierten Chirugie (CAS) wesentlich direkter im Dienste der eigentlichen chirugischen Behandlungsplanung und Therapie. Die CAS verwendet Methoden der Robotik, digitalen Bild- und Signalverarbeitung, künstlichen Intelligenz, numerischen Simulation, um nur einige zu nennen, zur patientenspezifischen Behandlungsplanung und zur intraoperativen Unterstützung des OP-Teams, allen voran des Chirurgen. Vor allen Dingen Fortschritte in der räumlichen Verfolgung von Werkzeugen und Patienten ("Tracking"), die Verfügbarkeit dreidimensionaler radiologischer Aufnahmen (CT, MRT, ...) und der Einsatz verschiedener Robotersysteme haben in den vergangenen Jahrzehnten den Einzug des Computers in den Operationssaal - medienwirksam - ermöglicht. Weniger prominent, jedoch keinesfalls von untergeordnetem praktischen Nutzen, sind Beispiele zur automatisierten Überwachung klinischer Messwerte, wie etwa Blutdruck oder Sauerstoffsättigung. Im Gegensatz zu den meist hochgradig verteilten und gut miteinander verwobenen Informationssystemen für die Krankenhausadministration und Patientendatenverwaltung, sind die Systeme der CAS heutzutage meist wenig oder überhaupt nicht miteinander und mit Hintergrundsdatenspeichern vernetzt. Eine Reihe wissenschaftlicher Publikationen und interdisziplinärer Workshops hat sich in den vergangen ein bis zwei Jahrzehnten mit den Problemen des Alltagseinsatzes von CAS Systemen befasst. Mit steigender Intensität wurde hierbei auf den Mangel an infrastrukturiellen Grundlagen für die Vernetzung intraoperativ eingesetzter CAS Systeme miteinander und mit den perioperativ eingesetzten Planungs-, Dokumentations- und Archivierungssystemen hingewiesen. Die sich daraus ergebenden negativen Einflüsse auf die Effizienz perioperativer Abläufe - jedes Gerät muss manuell in Betrieb genommen und mit den spezifischen Daten des nächsten Patienten gefüttert werden - sowie die zunehmende Aufmerksamkeit, welche der Operateur und sein Team auf die Überwachung und dem Betrieb der einzelnen Geräte verwenden muss, werden als eine der "Kinderkrankheiten" dieser relativ jungen Technologie betrachtet und stehen einer Verbreitung über die Grenzen einer engagierten technophilen Nutzergruppe hinaus im Wege. Die vorliegende Arbeit zeigt zwei parallel von einander (jedoch, im Sinne der Schnittstellenkompatibilität, nicht gänzlich unabhängig voneinander) zu betreibende Ansätze zur Integration von CAS Systemen. - Für den perioperativen Datenaustausch wird die Spezifikation zusätzlicher Datenstrukturen zum Transfer chirurgischer Planungsdaten im Rahmen des in radiologischen Bildverarbeitungssystemen weit verbreiteten DICOM Standards vorgeschlagen und an zwei Beispielen vorgeführt. Die Erweiterung des DICOM Standards für den perioperativen Einsatz ermöglicht hierbei die nahtlose Integration chirurgischer Planungssysteme in existierende "Picture Archiving and Communication Systems" (PACS), welche in den meisten Fällen auf dem DICOM Standard basieren oder zumindest damit kompatibel sind. Dadurch ist einerseits der Tatsache Rechnung getragen, dass die patientenspezifische OP-Planung in hohem Masse auf radiologischen Bildern basiert und andererseits sicher gestellt, dass die Planungsergebnisse entsprechend der geltenden Bestimmungen langfristig archiviert und gegen unbefugten Zugriff geschützt sind - PACS Server liefern hier bereits wohlerprobte Lösungen. - Für die integration intraoperativer CAS Systeme, wie etwa Navigationssysteme, Videobildquellen oder Sensoren zur Überwachung der Vitalparameter, wird das Konzept einer "chirurgischen Middleware" vorgestellt. Unter dem Namen TiCoLi wurde eine c++ Klassenbibliothek entwickelt, auf deren Grundlage die Konfiguration von ad-hoc Netzwerken während der OP-Vorbereitung mittels plug-and-play Mechanismen erleichtert wird. Nach erfolgter Konfiguration ermöglicht die TiCoLi den Austausch kontinuierlicher Datenströme sowie einzelner Datenpakete und Kommandos zwischen den Modulen einer verteilten CAS Anwendung durch ein Ethernet-basiertes Netzwerk. Die TiCoLi ist die erste frei verfügbare Klassenbibliothek welche diese Funktionalitäten dediziert für einen Einsatz im chirurgischen Umfeld vereinigt. Zum Nachweis der Tauglichkeit der gezeigten Spezifikationen und deren Implementierungen, werden zwei modulare CAS Anwendungen präsentiert, welche die vorgeschlagenen DICOM Erweiterungen zum perioperativen Austausch von Planungsergebnissen sowie die TiCoLi zum intraoperativen Datenaustausch von Messdaten unter echzeitnahen Anforderungen verwenden.
32

Suporte à recuperação de imagens médicas baseadas em conteúdo através de Histogramas Métricos.

Bueno, Josiane Maria 05 February 2002 (has links)
Os grandes centros médicos e hospitais de todo o mundo têm procurado integrar as informações de seus pacientes incluindo os exames de imagens efetuados (tomografia computadorizada, tomografia por ressonância magnética, ultrasson, medicina nuclear, etc.). Um sistema que integra as imagens junto às informações tradicionais é chamado de Sistema de Arquivamento e Comunicação de Imagens (Picture Archive and Communication System - PACS). Os sistemas PACS comerciais associam as imagens de exames às informações de pacientes através de chaves de consultas textuais e numéricas, não suportando consultas baseadas no conteúdo pictórico das imagens. Entretanto, muitas vezes o médico gostaria de recuperar as imagens armazenadas que fossem semelhantes (similares) a uma determinada imagem de consulta. Por exemplo, seja a consulta: "encontre as 10 imagens mais semelhantes à imagem Raio-X-tórax do Jõao da Silva". Ao responder a consultas desse tipo, o sistema permite que o médico relembre casos ocorridos anteriormente. Além disso, o conhecimento já gerado de exames e tratamentos anteriores pode ser recuperado mais rapidamente do que utilizando apenas a memória humana ou um sistema não automático de recuperação de informações. Um sistema com a capacidade de recuperar imagens utilizando o seu conteúdo pictórico é uma ferramenta valiosa para o auxílio ao diagnóstico médico. Esta tese apresenta a arquitetura de um PACS atualmente em desenvolvimento. Este sistema está sendo denominado mini-PACS. Tal sistema necessita da integração de três sistemas, a saber: - Um Sistema de Processamento de Imagens (SPI), o qual é responsável pela leitura e pré-processamento das imagens que são recebidas de diferentes dispositivos e possuem diferentes formatos. O SPI extrai as características relevantes das imagens, as quais serão utilizadas para a sua indexação e recuperação por conteúdo. - Um Sistema de Gerenciamento de Bases de Dados e Imagens (SGBDI), que permite a armazenagem e a recuperação de imagens baseada em seu conteúdo. O SGBDI utiliza uma estrutura métrica, a Slim-tree, que indexa as imagens através das características extraídas pelo SPI e possibilita responder consultas por similaridade. - Um Servidor de Web (SW), que disponibiliza o acesso às informações através da internet. A construção do Servidor de Web encontra-se fora do escopo do desenvolvimento desta tese. Porém, testes iniciais sobre a transferência e comunicação de imagens utilizando um servidor e aplicativos Java foram desenvolvidos para avaliar o comportamento do sistema. Entre as principais contribuições deste trabalho encontra-se um novo método de extração de características de imagens chamado histograma métrico. Os histogramas métricos permitem comparar imagens de diferentes tamanhos e mapeadas em faixas de quantização diferentes (se a alteração de brilho for linear). O tempo de resposta às consultas por similaridade utilizando histogramas métricos é, em média, 5 vezes menor do que o tempo de resposta utilizando histogramas tradicionais. Para permitir a indexação das imagens utilizando a Slim-tree foi necessário desenvolver uma nova função de distância métrica. Tal função de distância utiliza a diferença entre as áreas das curvas do histograma métrico. A construção da árvore de indexação utilizando os histogramas métricos chega a ser 10 vezes mais rápida do que com os histogramas tradicionais. As inovações e aperfeiçoamentos oriundos deste trabalho estão sendo integrados ao mini-PACS. Este sistema vem sendo desenvolvido de forma conjunta entre o Grupo de Bases de Dados e Imagens (GDBI) do Instituto de Ciências Matemáticas e de Computação da USP e o Centro de Ciências de Imagens e Física Médica (CCIFM) da Faculdade de Medicina de Ribeirão Preto da USP.
33

Pacs et mariages en France : une analyse économique

Leturcq, Marion 28 September 2011 (has links) (PDF)
Cette thèse porte sur les impacts économiques du pacs et du mariage en France. Elle s'articule autour de trois axes. Le chapitre 2 évalue l'impact de la fiscalité sur le nombre de pacs contractés en France. Le chapitre 3 cherche à déterminer si le pacs se substitue au mariage en étudiant l'évolution des taux de mariage et de l'âge au premier mariage depuis la mise en place du pacs in 1999. Le chapitre 4 s'interroge sur l'impact économique du mariage en évaluant l'effet du mariage sur les contraintes de crédit des couples. Si la fiscalité a joué un rôle indéniable dans la progression du nombre de pacs contractés chaque année en France, celui-ci ne semble pas avoir augmenté au détriment du mariage, dont l'évolution récente prolonge la modification du paysage matrimonial observée depuis 25 ans, à savoir une baisse des taux de mariage et un recul de l'âge au premier mariage. Si la baisse du nombre de mariages contractés, associée au développement de la cohabitation hors mariage introduit une distinction entre couples non-mariés et couples mariés, ces derniers ont plus souvent des projets d'investissement mais ils ne sont pas pour autant avantagés sur le marché du crédit. Ils souffrent de plus mauvaises conditions d'emprunt, traduisant une sélection dans le mariage des couples les plus enclins à investir.
34

Data Propagation and Self-Configuring Directory Services in a Distributed Environment / Data Propagation and Self-Configuring Directory Services in a Distributed Environment

Hedin, Svante January 2001 (has links)
<p>The Swedish field of digital X-ray imaging has since several years relied heavily on distributed information systems and digital storage containers. </p><p>To ensure accurate and safe radiological reporting, Swedish software-firm eCare AB delivers a system called Feedback—the first and only quality assurance IT support product of its kind. This thesis covers several aspects of the design and implementation of future versions of this software platform. </p><p>The focus lies on distributed directory services and models for secure and robust data propagation in TCP/IP networks. For data propagation, a new application, InfoBroker, has been designed and implemented to facilitate integration between Feedback and other medical IT support systems. The directory services, introduced in this thesis as the Feedback Directory Services, have been designed on the architectural level. A combination of CORBA and Java Enterprise Edition is suggested as the implementation platform.</p>
35

Designing a framework for simulating radiology information systems

Lindblad, Erik January 2008 (has links)
<p>In this thesis, a very flexible framework for simulating RIS is designed to beused for Infobroker testing. Infobroker is an application developed by MawellSvenska AB that connects RIS and PACS to achieve interoperability by enablingimage and journal data transmission between radiology sites. To put the project in context, the field of medical informatics, RIS and PACS systems and common protocols and standards are explored. A proof-of-concept implementation of the proposed design shows its potential and verifies that it works. The thesis concludes that a more specialized approach is preferred.</p>
36

Transforming Medical Imaging Applications into Collaborative PACS-based Telemedical Systems

Maani, Rouzbeh 13 October 2010 (has links)
Many medical imaging applications have been developed so far; however, many of them do not support collaboration and are not remotely accessible (i.e., Telemedicine). Medical imaging applications are not practical for use in clinical workflows unless they are able to communicate with the Picture Archiving and Communications System (PACS). This thesis presents an approach based on a three-tier architecture and provides several components to transform medical imaging applications into collaborative, PACS-based, telemedical systems. A novel method is presented to support PACS connectivity. The method is to use the Digital Imaging and COmmunication in Medicine (DICOM) protocol and enhance transmission time by employing a combination of parallelism and compression methods. Experimental results show up to 1.63 speedup over Local Area Networks (LANs) and up to 16.34 speedup over Wide Area Networks (WANs) compared to the current method of medical data transmission.
37

Transforming Medical Imaging Applications into Collaborative PACS-based Telemedical Systems

Maani, Rouzbeh 13 October 2010 (has links)
Many medical imaging applications have been developed so far; however, many of them do not support collaboration and are not remotely accessible (i.e., Telemedicine). Medical imaging applications are not practical for use in clinical workflows unless they are able to communicate with the Picture Archiving and Communications System (PACS). This thesis presents an approach based on a three-tier architecture and provides several components to transform medical imaging applications into collaborative, PACS-based, telemedical systems. A novel method is presented to support PACS connectivity. The method is to use the Digital Imaging and COmmunication in Medicine (DICOM) protocol and enhance transmission time by employing a combination of parallelism and compression methods. Experimental results show up to 1.63 speedup over Local Area Networks (LANs) and up to 16.34 speedup over Wide Area Networks (WANs) compared to the current method of medical data transmission.
38

Estimation of the size of the media necessary to construct a medical image database

池田, 充, Ikeda, Mitsuru, 石垣, 武男, Ishigaki, Takeo, 山内, 一信, Yamauchi, Kazunobu 01 1900 (has links)
No description available.
39

Designing a framework for simulating radiology information systems

Lindblad, Erik January 2008 (has links)
In this thesis, a very flexible framework for simulating RIS is designed to beused for Infobroker testing. Infobroker is an application developed by MawellSvenska AB that connects RIS and PACS to achieve interoperability by enablingimage and journal data transmission between radiology sites. To put the project in context, the field of medical informatics, RIS and PACS systems and common protocols and standards are explored. A proof-of-concept implementation of the proposed design shows its potential and verifies that it works. The thesis concludes that a more specialized approach is preferred.
40

Data Propagation and Self-Configuring Directory Services in a Distributed Environment / Data Propagation and Self-Configuring Directory Services in a Distributed Environment

Hedin, Svante January 2001 (has links)
The Swedish field of digital X-ray imaging has since several years relied heavily on distributed information systems and digital storage containers. To ensure accurate and safe radiological reporting, Swedish software-firm eCare AB delivers a system called Feedback—the first and only quality assurance IT support product of its kind. This thesis covers several aspects of the design and implementation of future versions of this software platform. The focus lies on distributed directory services and models for secure and robust data propagation in TCP/IP networks. For data propagation, a new application, InfoBroker, has been designed and implemented to facilitate integration between Feedback and other medical IT support systems. The directory services, introduced in this thesis as the Feedback Directory Services, have been designed on the architectural level. A combination of CORBA and Java Enterprise Edition is suggested as the implementation platform.

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