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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.
1

Modelo anatômico de ventriculomegalia para treinamento neuroendoscópico / Ventriculomegaly anatomical models for neuroendoscopy training

Ferreira, Christian Diniz 28 May 2015 (has links)
OBJETIVO: Desenvolver peças anatômicas que simulem uma condição real de ventriculomegalia para serem utilizadas como uma ferramenta no treinamento dos neurocirurgiões nas técnicas de neuroendoscopia e viabilizar estudo anatômico dos ventrículos. MÉTODO: Foram utilizadas vinte peças anatômicas de encéfalo de cadáveres de indigentes, com a aprovação do Comitê de Ética em pesquisa da FMUSP sob o número 046/10. As peças foram retiradas da base do crânio com a persistência da superfície óssea (parte da calvária) para serem submetidas aos seguintes procedimentos: canulação do IV ventrículo por meio da abertura mediana do IV ventrículo (forame de Magendie); tomografias pré-experimento e injeção de água destilada no sistema ventricular. A água injetada estava à temperatura ambiente e os cérebros foram resfriados até 4º C e, após 12 horas, foram congelados a uma temperatura de 0º C (no estado sólido) por 24 horas. Esses procedimentos foram realizados na frequência de três vezes. Após o experimento, foram realizadas tomografias pós-experimento e procedimentos neuroendoscópicos ventriculares. Foram excluídos encéfalos com lesões traumáticas ou antecedentes de enfermidades transmissíveis. Não foram critérios de exclusão o sexo e a idade. Foram avaliadas, nas imagens tomográficas, a variação pré e pós-experimento dos seguintes parâmetros: coeficiente corno frontal/diâmetro interno; índice de Evan; e tamanho do corno temporal. As análises estatísticas foram realizadas no programa SPSS (Statistical Package for the Social Sciences) versão 13, para ambos os grupos. RESULTADOS: A avaliação da relação Corno frontal/Diâmetro interno, antes e pós-experimento apresentou média de 11,98% e 19,46%, respectivamente. Estudo estatístico (t Student) mostrou diferença estatística (t= -5142, gl =19; p < 0,01). O Índice de Evan também apresentou diferença significativa (t = -5,172, gl = 9; p < 0,01) entre os resultados antes (média de 10,86%) e após experimento (média de 18,35%). A análise do tamanho do corno temporal mostrou diferença significativa entre os grupos antes e depois do experimento (t = -2,297, gl = 9; p< 0,01), indicando que o tamanho mediano do Corno Temporal é maior após o experimento (média de 2,65cm). CONCLUSÕES: A exploração das características físico-químicas anômalas da molécula da água pode nos fornecer um bom mecanismo expansor de cavidades ventriculares para a indução de ventriculomegalia em uma peça anatômica de encéfalo, em que o endoscópio poderá ser introduzido pelas vias habituais, podendo, assim, realizar observação anatômica e simular o procedimento cirúrgico com a mesma sensibilidade tátil que irá encontrar no procedimento real / PURPOSE: To develop anatomical models which simulate real conditions of ventriculomegaly and to use them as tools to train neuroendoscopic techniques and allow the study of the ventricles. METHODS: A total of twenty brains, with the approval of the Ethics in Research Committee from FMUSP (046/10) were used to perform this research. The brains were separated from the skull base, but keeping part of the calvaria, and then underwent the following procedures: cannulation of the fourth ventricle through the median open of the fourth ventricle (foramen of Magendie); CT scans performed before the experiment; and then injection of distilled water into the ventricular system. The water was injected at room temperature, and then the brains were cooled to 4ºC. After 12 hours, they were then frozen at 0ºC for 24 hours.These procedures were repeated three times. After the experiment,CT scans were performed after the injections and neuroendoscopic procedures. Brains, which had traumatic injuries or history of infectious diseases, were excluded. Gender and age were not exclusion criteria. The statistical analysis was performed with the SPSS program (Statistical Package for the Social Sciences) version 13, for both groups. To assess the variation of the frontal horn (FH)/internal diameter (ID) coefficient, such as Evan\'s index\'s variation, and to analyze the temporal horn (TH) size, thet-Student test was used. RESULTS: The results of the t-Student test showed that the FH/ID, with an average of 11.98% before the experiment, had significant difference (t = -5.142, gl = 19; p < 0.01) after the experiment, with an average of19.46%. The Evan\'s index also showed a significant difference (t = -5.172, gl = 9; p < 0,01) with an initial average of 10.86% and a final average of 18.35%. The analysis of the temporal horn size showed a significant difference between the size before and after the experiment (t = -2.297, gl = 9; p < 0.01), indicating the significant increase of the temporal horn (with an initial average of 0.02cm and a final average of 2.65cm). CONCLUSIONS: The use of the anomalous physical and chemical characteristics of water can provide us with a good expanding mechanism of the ventricular system, creating ventriculomegaly in anatomical models, allowing the endoscope to be introduced by the usual approaches, to perform anatomical observation, and to simulate a surgical procedure with the same sensitivity of a real procedure
2

Modelo anatômico de ventriculomegalia para treinamento neuroendoscópico / Ventriculomegaly anatomical models for neuroendoscopy training

Christian Diniz Ferreira 28 May 2015 (has links)
OBJETIVO: Desenvolver peças anatômicas que simulem uma condição real de ventriculomegalia para serem utilizadas como uma ferramenta no treinamento dos neurocirurgiões nas técnicas de neuroendoscopia e viabilizar estudo anatômico dos ventrículos. MÉTODO: Foram utilizadas vinte peças anatômicas de encéfalo de cadáveres de indigentes, com a aprovação do Comitê de Ética em pesquisa da FMUSP sob o número 046/10. As peças foram retiradas da base do crânio com a persistência da superfície óssea (parte da calvária) para serem submetidas aos seguintes procedimentos: canulação do IV ventrículo por meio da abertura mediana do IV ventrículo (forame de Magendie); tomografias pré-experimento e injeção de água destilada no sistema ventricular. A água injetada estava à temperatura ambiente e os cérebros foram resfriados até 4º C e, após 12 horas, foram congelados a uma temperatura de 0º C (no estado sólido) por 24 horas. Esses procedimentos foram realizados na frequência de três vezes. Após o experimento, foram realizadas tomografias pós-experimento e procedimentos neuroendoscópicos ventriculares. Foram excluídos encéfalos com lesões traumáticas ou antecedentes de enfermidades transmissíveis. Não foram critérios de exclusão o sexo e a idade. Foram avaliadas, nas imagens tomográficas, a variação pré e pós-experimento dos seguintes parâmetros: coeficiente corno frontal/diâmetro interno; índice de Evan; e tamanho do corno temporal. As análises estatísticas foram realizadas no programa SPSS (Statistical Package for the Social Sciences) versão 13, para ambos os grupos. RESULTADOS: A avaliação da relação Corno frontal/Diâmetro interno, antes e pós-experimento apresentou média de 11,98% e 19,46%, respectivamente. Estudo estatístico (t Student) mostrou diferença estatística (t= -5142, gl =19; p < 0,01). O Índice de Evan também apresentou diferença significativa (t = -5,172, gl = 9; p < 0,01) entre os resultados antes (média de 10,86%) e após experimento (média de 18,35%). A análise do tamanho do corno temporal mostrou diferença significativa entre os grupos antes e depois do experimento (t = -2,297, gl = 9; p< 0,01), indicando que o tamanho mediano do Corno Temporal é maior após o experimento (média de 2,65cm). CONCLUSÕES: A exploração das características físico-químicas anômalas da molécula da água pode nos fornecer um bom mecanismo expansor de cavidades ventriculares para a indução de ventriculomegalia em uma peça anatômica de encéfalo, em que o endoscópio poderá ser introduzido pelas vias habituais, podendo, assim, realizar observação anatômica e simular o procedimento cirúrgico com a mesma sensibilidade tátil que irá encontrar no procedimento real / PURPOSE: To develop anatomical models which simulate real conditions of ventriculomegaly and to use them as tools to train neuroendoscopic techniques and allow the study of the ventricles. METHODS: A total of twenty brains, with the approval of the Ethics in Research Committee from FMUSP (046/10) were used to perform this research. The brains were separated from the skull base, but keeping part of the calvaria, and then underwent the following procedures: cannulation of the fourth ventricle through the median open of the fourth ventricle (foramen of Magendie); CT scans performed before the experiment; and then injection of distilled water into the ventricular system. The water was injected at room temperature, and then the brains were cooled to 4ºC. After 12 hours, they were then frozen at 0ºC for 24 hours.These procedures were repeated three times. After the experiment,CT scans were performed after the injections and neuroendoscopic procedures. Brains, which had traumatic injuries or history of infectious diseases, were excluded. Gender and age were not exclusion criteria. The statistical analysis was performed with the SPSS program (Statistical Package for the Social Sciences) version 13, for both groups. To assess the variation of the frontal horn (FH)/internal diameter (ID) coefficient, such as Evan\'s index\'s variation, and to analyze the temporal horn (TH) size, thet-Student test was used. RESULTS: The results of the t-Student test showed that the FH/ID, with an average of 11.98% before the experiment, had significant difference (t = -5.142, gl = 19; p < 0.01) after the experiment, with an average of19.46%. The Evan\'s index also showed a significant difference (t = -5.172, gl = 9; p < 0,01) with an initial average of 10.86% and a final average of 18.35%. The analysis of the temporal horn size showed a significant difference between the size before and after the experiment (t = -2.297, gl = 9; p < 0.01), indicating the significant increase of the temporal horn (with an initial average of 0.02cm and a final average of 2.65cm). CONCLUSIONS: The use of the anomalous physical and chemical characteristics of water can provide us with a good expanding mechanism of the ventricular system, creating ventriculomegaly in anatomical models, allowing the endoscope to be introduced by the usual approaches, to perform anatomical observation, and to simulate a surgical procedure with the same sensitivity of a real procedure
3

Vetenskapens behov av avbildningar : En objektbiografisk fallstudie av Félix Thiberts moulager / The Need for Imaging in Science : An Object Biographical Case Study of Félix Thibert’s Moulages

Toudert, Thérèse January 2019 (has links)
This thesis investigates a part of the material culture of higher education through an object biographical case study of Félix Thibert’s moulages. The object biography operates with a diachronic perspective that offers an object-centered historiography of university collections, revealing that the need for collecting and imaging in science consistently remains, even though the role and significance of pathological moulages in research and education have changed over time. The moulages are epistemic things as described by Hans-Jörg Rheinberger. They embody what we do not yet know and they become marginalized when no one expects them to generate new discoveries. Their ontology and function are dependent on the dominating epistemic culture. John V. Pickstone outlines three ways of knowing, which gradually have dominated since the Renaissance: natural history, analysis and experiment. Thibert’s moulages are clearly anchored in analysis as a way of knowing for which the museum is an important arena. The findings of this thesis show that university museums and their collections were of immense importance for the production of knowledge during the 19th century, while today they often fall short of their knowledge-generating potential. There are nevertheless methods that can help them reach their full potential, among them a displaying method proposed by Karin Tybjerg considered in this thesis and the object biography of which this thesis consists. This is a two-year master’s thesis in Museum and Cultural Heritage Studies.
4

Propagation de la variabilité de la morphologie humaine sur le débit d'absorption spécifique en dosimétrie numérique. / Propagation of the variability of the human morphology on the Specific Absorption Rate in numerical dosimetry

El Habachi, Aimad Abdeslam 31 January 2011 (has links)
Dans ce mémoire, nous étudions l’exposition aux ondes électromagnétiques l’échelle d’une population. Cette étude est réalisée pour une exposition à une onde plane orientée frontalement sur des modèles anatomiques du corps humains (fantômes) avec une puissance incidente de 1W/m2 et une fréquence de 2.1 GHz. Pour ce faire, l’idée est de construire un modèle du WBSAR (Whole Body averaged Specific Absorption Rate) en fonction de lamorphologie. Les facteurs morphologiques influençant le WBSAR ont été identifiés à l’aide des fantômes existant dont le nombre se limite à 18 et des modèles de régressions. Cette analyse préliminaire montre que les facteurs morphologiques externes (taille, poids ...) seuls ne suffisent pas pour construire un tel modèle, mais l’introduction des facteurs morphologiques internes (muscles, graisse ...) est nécessaire. L’absence de données statistiques sur les facteurs morphologiques internes de populations nous a conduits à intégrer des connaissances apriori sur ces facteursafin d’étudier l’exposition d’une population donnée. Des lois paramétriques usuelles et des mélanges de gaussiennes sont utilisés pour modéliser ces facteurs internes afin d’étudier leur influence sur le quantile du WBSAR à 95 %.L’utilisation des fantômes homogènes où le fantôme homogène est obtenu en remplaçant tous les tissus internes par un unique tissu équivalent. Ces fantômes homogènes permettent de s’affranchir de l’influence de la morphologie interne dans un modèle du WBSAR et facilitent également leur déformation par une technique de morphing. Ainsi nous avons pu enrichir la base de fantômes existant. Pour donner une estimation du quantile du WBSAR à 95 %, nous avons mis en place un plan d’expériences séquentiel qui repose sur un modèle paramétrique du WBSAR et l’inférence bayésienne et qui permet de raffiner la région à 95 %. Cette approche nous a permis de trouver le quantile à 95 % pour une population et un exemple de fantôme correspondant. Cependant, cette approche ne permet pas d’obtenir une estimation de toute la distribution du WBSAR. Afin d’obtenir une estimation de toute cette distribution, nous avons construit une surface de réponse en utilisant les polynômes de chaos. Dans l’objectif d’obtenirdes résultats cohérents nous avons effectué un changement de variables permettant de traduire les connaissances physiques dans cette surface de réponse. / In this report, a study of the exposure to electromagnetic waves at the level of population is proposed. This study is conducted in the case of a plane wave oriented frontally on anatomical models (phantoms) with an incident power of 1W/m2 and at the frequency of 2.1 GHz. For this purpose, the idea is to build a surrogate model of the WBSAR (Whole Body averaged Specific Absorption Rate) as a function of morphology. An identificationof morphological factor is performed using the limited number of phantoms (18phantoms)and different regressions. This analysis shows that to use only external morphological factors (height, weight ...) is not sufficient to build such surrogate model and that internal morphological factors (muscles, fat ...) are also important. The absence of statistical data on internal morphology conducts us to introduce some prior knowledge on these internal factors to study the exposure for a given population. Some parametric laws and Gaussian mixture are used to study their influence on the quantile of the WBSAR at 95 The lack of data on internal morphology led us to consider homogeneous phantoms instead of the heterogeneous one. In homogeneous phantoms, all the internal tissues are substituted by an equivalent tissue. These homogeneous phantoms allow us to overcome the influence of internal morphology for a WBSAR model and to use a morphing technique to increase the database of phantoms. To give an estimation of the WBSAR quantile at 95 %, a sequential experiment design is used. This approach is based on a parametric model and Bayesian inference. This experiment design allows us to estimate the quantile at 95 for a given population and an example of one corresponding phantom. Nevertheless, this approach does not allow one to estimate the whole distribution of the WBSAR for a given population. To give an estimate of this distribution a surface of response is established using polynomial chaos. This approach gives incoherent results with the physical phenomenon. To obtain coherent results, physical knowledge is introduced by variables changing in this responsesurface.
5

Nursing Simulation: A Review of the Past 40 Years

Nehring, Wendy M., Lashley, Felissa R. 01 August 2009 (has links)
Simulation, in its many forms, has been a part of nursing education and practice for many years. The use of games, computer-assisted instruction, standardized patients, virtual reality, and low-fidelity to high-fidelity mannequins have appeared in the past 40 years, whereas anatomical models, partial task trainers, and role playing were used earlier. A historical examination of these many forms of simulation in nursing is presented, followed by a discussion of the roles of simulation in both nursing education and practice. A viewpoint concerning the future of simulation in nursing concludes this article.
6

Investigación para el desarrollo de un protocolo para fabricación aditiva de modelos anatómicos en centros de salud

de Rossi Estrada, Marco 10 June 2022 (has links)
[ES] La fabricación aditiva, también llamada impresión 3D, ha tenido un gran impacto en la industria. La capacidad de fabricar modelos complejos y personalizados a bajo coste se adapta muy bien para algunas aplicaciones, sustituyendo procesos de fabricación tradicional y ofreciendo nuevas oportunidades. En medicina, la fabricación personalizada de modelos complejos ha encontrado muchas aplicaciones, desde réplicas de patologías para la educación hasta implantes hechos a medida y remplazo de órganos. De todas las posibilidades de esta tecnología en medicina, la fabricación de modelos anatómicos a partir de imágenes médicas ofrece un excelente balance entre facilidad de implementación y beneficio, esto la hace una aplicación perfecta para ser usada ampliamente en los hospitales. La fabricación aditiva de modelos anatómicos es un campo que ha suscitado considerable entusiasmo en los últimos años. La comunidad médica ve esta herramienta como el siguiente paso generacional en la visualización clínica, ofreciendo grandes beneficios para los pacientes y el sistema de salud. Debido al gran interés, hay muchos investigadores que han evaluado el impacto de esta tecnología en la práctica médica, midiendo los beneficios médicos que puedan tener estos modelos anatómicos. En general, los resultados muestran que hay reducción de tiempo de quirófano, menor morbilidad y mortalidad al igual que menor estrés y denuncias por parte de pacientes. A pesar de estos resultados prometedores, no hay muchos estudios realizados sobre cuál debe ser el proceso para garantizar la reproducibilidad y seguridad de estos modelos, un tema que es de gran importancia para poder cumplir con las regulaciones actuales, que exigen protocolos de fabricación y sistemas de calidad para este proceso. Debemos observar que, aunque el proceso para obtener modelos anatómicos es más fácil que otras aplicaciones de esta tecnología, no es un proceso trivial. Es un trabajo complejo con múltiples pasos que Involucra a varios especialistas para su correcta realización. Actualmente el hospital es el entorno ideal para poder fabricar estos modelos, permite un mayor control del proceso, facilita la colaboración multidisciplinar necesaria y reduce considerablemente los requisitos legales que rigen los dispositivos médicos. El objetivo de esta investigación es desarrollar un protocolo detallado y optimizado que cumpla con los requisitos técnicos, médicos y legales para poder implementar esta tecnología emergente de forma segura y eficiente en centros de salud. Para alcanzar este objetivo, las metodologías observadas fueron la revisión por literatura, la investigación doctrinal legal y la investigación acción empleada en los diferentes casos estudiados. Los casos se han elegido buscando la mayor diversidad posible bajo el criterio de conveniencia en el horizonte temporal contemplado, dada la diversidad compleja del estudio realizado. Gracias a la colaboración con varias instituciones médicas y de educación, este protocolo se pudo implementar en diversos contextos, mejorándolo progresivamente al ponerlo a prueba con casos reales, mediante el trabajo continuo con los expertos. El resultado es un protocolo que incluye varios años de experiencia y que ha sido aplicado en un amplio rango de especialidades. Este protocolo es relativamente sencillo de seguir y cumple con los principales requisitos para ser implementado en hospitales. / [CA] La fabricació additiva, també anomenada impressió 3D, ha tingut un gran impacte en la indústria. La capacitat de fabricar models complexos i personalitzats a baix cost s' adapta molt bé per a algunes aplicacions, substituint processos de fabricació tradicional i oferint noves oportunitats. En medicina, la fabricació personalitzada de models complexos ha trobat moltes aplicacions, des de rèpliques de patologies per a l'educació fins a implants fets a mida i òrgans. De totes les possibilitats d'aquesta tecnologia en medicina, la fabricació de models anatòmics a partir d'imatges mèdiques ofereix un excel·lent balanç entre facilitat d'implementació i benefici, això la fa una aplicació perfecta per ser usada àmpliament als hospitals. La fabricació additiva de models anatòmics és un camp que ha suscitat considerable entusiasme en els últims anys. La comunitat mèdica veu aquesta eina com el següent pas generacional en la visualització clínica, oferint grans beneficis per als pacients i el sistema de salut. A causa del gran interès, hi ha molts investigadors que han avaluat l'impacte d'aquesta tecnologia en la pràctica mèdica, mesurant els beneficis mèdics que puguen tenir aquests models anatòmics. En general, els resultats mostren que hi ha reducció de temps de quiròfan, menor morbiditat i mortalitat igual que menor estrès i denúncies per part de pacients. Malgrat aquests resultats prometedors, no hi ha molts estudis realitzats sobre quin ha de ser el procés per garantir la reproduïbilitat i seguretat d' aquests models, un tema que és de gran importància per poder complir amb les regulacions actuals, que exigeixen protocols de fabricació i sistemes de qualitat per a aquest procés. Hem d'observar que, tot i que el procés per obtenir models anatòmics és més fàcil que altres aplicacions d'aquesta tecnologia, no és un procés trivial. És un treball complex amb múltiples passos que Involucra diversos especialistes per a la seva correcta realització. Actualment l'hospital és l'entorn ideal per poder fabricar aquests models, permet un major control del procés, facilita la col·laboració multidisciplinària necessària i redueix considerablement els requisits legals que regeixen els dispositius mèdics. L'objectiu d'aquesta investigació és desenvolupar un protocol detallat i optimitzat que compleix amb els requisits tècnics, mèdics i legals per poder implementar aquesta tecnologia emergent de forma segura i eficient en centres de salut. Per assolir aquest objectiu, les metodologies observades van ser la revisió per literatura, la investigació doctrinal legal i la investigació acció emprada en els diferents casos estudiats. Els casos s' han triat buscant la major diversitat possible sota el criteri de conveniència en l' horitzó temporal contemplat, atesa la diversitat complexa de l' estudi realitzat. Gràcies a la col·laboració amb diverses institucions mèdiques i d'educació, aquest protocol es va poder implementar en diversos contextos, millorant-lo progressivament en posar-lo a prova amb casos reals, mitjançant el treball continu amb els experts. El resultat és un protocol que inclou diversos anys d' experiència i que ha estat aplicat en un ampli rang d' especialitats. Aquest protocol és relativament senzill de seguir i compleix amb els principals requisits per ser implementat en hospitals. / [EN] Additive manufacturing, also called 3D printing, has had a huge impact on the industry. The ability to manufacture complex and customized models at a low cost is well suited for some applications, replacing traditional manufacturing processes and offering new opportunities. In medicine, the custom manufacture of complex models has found many applications, from replicas of pathologies for education to custom-made implants and organ replacement. Of all the possibilities of this technology in medicine, the manufacture of anatomical models from medical images offers an excellent balance between ease of implementation and benefit, this makes it a perfect application to be widely used in hospitals. Additive manufacturing of anatomical models is a field that has attracted considerable enthusiasm in recent years. The medical community sees this tool as the next generational step in clinical visualization, offering great benefits for patients and the healthcare system. Due to the great interest, there are many researchers who have evaluated the impact of this technology on medical practice, measuring the medical benefits that these anatomical models may have. In general, the results show that there is a reduction in operating room time, lower morbidity and mortality as well as less stress and complaints from patients. Despite these promising results, there are not many studies conducted on what the process should be to guarantee the reproducibility and safety of these models, an issue that is of great importance to be able to comply with current regulations, which require manufacturing protocols and quality systems for this process. We should note that although the process for obtaining anatomical models is easier than other applications of this technology, it is not a trivial process. It is a complex work with multiple steps that involves several specialists for its correct realization. Currently the hospital is the ideal environment to be able to manufacture these models, it allows greater control of the process, facilitates the necessary multidisciplinary collaboration, and considerably reduces the legal requirements that govern medical devices. The objective of this research is to develop a detailed and optimized protocol that meets the technical, medical, and legal requirements to implement this technology in hospitals. To achieve this objective, the methodologies observed consisted of literature review, legal doctrinal research and action research used in the multiple cases studied. The cases have been selected seeking the greatest possible diversity under the criterion of convenience in the time horizon contemplated, given the complex diversity of the study carried out. Thanks to the collaboration with several medical and educational institutions, this protocol could be implemented in various contexts, progressively improving it by testing it with real cases, through continuous work with experts. The result is a protocol that includes several years of experience and has been applied in a wide range of specialties. It is relatively simple to follow and complies with most requirements to be implemented in hospitals. / De Rossi Estrada, M. (2022). Investigación para el desarrollo de un protocolo para fabricación aditiva de modelos anatómicos en centros de salud [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/183303 / TESIS

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