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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.
281

Deux résultats d'analyse harmonique sur un groupe P-adique tordu / Two results of Harmonic Anlysis on a twisted p-adic group

Cohen, Joël 10 December 2013 (has links)
Dans cette thèse, nous montrons deux résultats d'analyse harmonique sur un groupe réductif p-adique tordu.Le premier résultat est un analogue non connexe au théorème matriciel de Paley Wiener. Soit G réductif p-adique (non nécessairement connexe). L'algèbre de Hecke des fonctions complexes sur G localement constantes à support compact agit les représentations complexe lisses irréductibles de G. L'action d'une fonction est vue comme sa transformée de Fourier. Le théorème fournit une caractérisation de l'image de l'algèbre de Hecke par la transformée de Fourier, ainsi qu'une formule d'inversion.Le second résultat établit une identité spectrale sur le groupe GLn tordu (avec n pair, sur un corps p-adique) pour l'intégrale orbitale tordue sur la classe de conjugaison tordue stable des matrices antisymétriques inversibles. Cette dernière s'exprime comme une intégrale sur les représentations irréductibles tempérées auto-duales de GLn dont le paramètre de Langlands est symplectique. La preuve repose sur le transfert endoscopique. / In this thesis, we show tow results of Harmonic Analysis on réductive p-adic group.The first results extends the matrix Paley-Wiener theorem to the non-connected case. Let G be reductive (non necessarily connected) p-adic group. The Hecke algebra of compactly supported locally constant complex functions on G acts on complex smooth irreducible representations of G. The action of a given function is seen as its Fourier transform. The theorem characterizes the image of the Hecke algebra under the Fourier transform and provides an inversion formula.The second result is the proof of a spectral identity on the so-called twisted GLn group (where n is even, on a p-adic field) for the twisted orbital integral over the twisted stable conjugacy class of antisymetric invertible matrices. We express it as an integral over those irreducible tempered auto-dual representations of GLn whose Langlands' parameter is symplectic. Our proof uses endoscopic transfer.
282

Efeito do dispositivo endoscópico temporário de exclusão duodeno jejunal na resistência insulínica e no risco cardiovascular em pacientes obesos com diabetes tipo 2 / Effect of the duodeno jejunal bypass liner in insulin resistance and cardiovascular risk in obese patients with type 2 diabetes

Ivan Roberto Bonotto Orso 08 October 2013 (has links)
OBJETIVO: Avaliar a eficácia do dispositivo endoscópico temporário de exclusão duodeno jejunal (DEED) na redução da resistência à insulina e do risco cardiovascular em pacientes obesos mórbidos portadores de diabetes tipo 2 (DMT2), utilizando a relação Triglicerídeos/colesterol HDL (TG/HDL), porcentagem de perda de peso e controle glicêmico. MÉTODO: Neste estudo foram incluídos 54 pacientes implantados com o DEED e acompanhados por um período de 6 meses. Todos apresentavam uma relação TG/HDL com valor acima de 3,5, sugerindo uma maior resistência insulínica e um perfil lipídico compatível com um maior risco cardiovascular. O valor da relação inicial foi comparado com o valor obtido após 6 meses do implante do dispositivo, com o objetivo de avaliar se houve redução desse valor, indicando melhora na resistência insulínica e redução do risco cardiovascular. Também foi avaliada a melhora dos níveis de hemoglobina glicada (HbA1c) e a perda de peso obtida com o uso do dispositivo. Estes dois últimos achados foram correlacionados com a redução da relação TG/HDL para avaliar a presença de dependência entre os fatores. RESULTADOS: Todos os pacientes implantados com o DEED apresentaram redução significativa dos níveis de HbA1c, sendo que a maior parte dos pacientes (70,3%) obtiveram o controle do diabetes, com níveis abaixo de 7% ao final do estudo. Todos os pacientes também apresentaram redução do peso, com perda média de 12,6% do peso absoluto inicial. Foi observada redução da relação TG/HDL de 5,75 para 4,36 ao final do estudo (p 0,0001), com 42,6% dos pacientes apresentando relação final abaixo de 3,5. A melhora da relação TG/HDL apresentou uma importante associação com uma perda de peso maior que 10% do peso inicial. CONCLUSÃO: O DEED mantido por um período de 6 meses é eficaz na obtenção do controle do diabetes tipo 2, perda de peso e redução da relação TG/HDL em pacientes obesos mórbidos portadores de diabetes mellitus tipo 2. Porém, a melhora da relação TG/HDL está fortemente associada à perda de mais de 10% do peso inicial / OBJECTIVE: To evaluate the efficacy of the duodeno jejunal bypass liner (DJBL) in reducing insulin resistance and cardiovascular risk in morbidly obese patients with type 2 diabetes (T2DM). For this purpose we used the Triglycerides / HDL cholesterol ratio (TG / HDL), percentage of weight loss and glycemic control. METHODS: This study included 54 patients implanted with the DJBL and followed for a period of 6 months. All had a TG / HDL ratio equal or above 3.5, suggesting greater insulin resistance and lipid profile consistent with increased cardiovascular risk. The initial value of the ratio was compared with the value obtained 6 months after the device implantation, in order to assess whether this value decreased, indicating an improvement in insulin resistance and reduction in the cardiovascular risk. We also evaluated the improvement in glycated hemoglobin (HbA1c) and weight loss achieved with the device, and its relationship with the reduction of TG/HDL ratio. RESULTS: All patients implanted with the DJBL showed significant reduction in HbA1c levels. Most patients (70.3%) achieved diabetes control, with HbA1c levels below 7% by the end of the study. All patients also had a statistically significant weight reduction, with an average loss of 12.6% of initial weight. We observed an important improvement in insulin resistance and metabolic syndrome, with a significant reduction of the TG/HDL ratio from 5.75 to 4.36 (p = 0.0001) and 42.6% of the patients presenting a TG/HDL ratio lower than 3.5 at the end of the study. The improvement of the TG / HDL ratio presented a significant association with weight loss greater than 10% of initial weight. CONCLUSION: The DJBL maintained for a period of 6 months is effective in obtaining control of type 2 diabetes, weight loss and reduction in the TG / HDL ratio in morbidly obese patients with diabetes mellitus type 2. However, the improvement of the TG / HDL ratio is strongly associated with loss of more than 10% of the initial weight
283

Revisão sistemática e metanálise do tratamento endoscópico do reganho de peso pós-derivação gástrica em Y-de-Roux / Systematic review and meta-analysis of the endoscopic treatment of weight regain following Roux-en-Y gastric bypass

Vítor Ottoboni Brunaldi 03 April 2018 (has links)
Introdução: A derivação gástrica em Y-de-Roux (DGYR) é um dos procedimentos bariátricos mais realizados em todo o mundo. Apesar de sua alta eficácia, significativa proporção de pacientes recupera parte do peso perdido. Várias terapias endoscópicas foram introduzidas como alternativas para tratar o reganho de peso, mas a maioria dos artigos publicados tem amostra relativamente pequena, com dados pouco claros e de curto prazo. Objetivo: Avaliar sistematicamente a eficácia das terapias endoscópicas para reganho de peso pós-DGYR. Métodos: Foram realizadas buscas nas bases MEDLINE, EMBASE, Scopus, Web of Science, Cochrane, OVID, CINAHL/EBSCo, LILACS/Bireme e literatura cinzenta. Os desfechos primários avaliados foram perda absoluta de peso (PAP), perda de excesso de peso (PEP) e perda total de peso corporal (PPTP). Resultados: Trinta e dois estudos foram incluídos na análise qualitativa. Vinte e seis trabalhos envolvendo 1148 pacientes descreveram sutura endoscópica de espessura total (SET) e PAP, PEP e PPTP em 3 meses foram 8,5±2,9kg, 21,6±9,3% e 7,3±2,6%, respectivamente. Aos 6 meses, foram de 8,6±3,5kg, 23,7±12,3% e 8,0±3,9%. Aos 12 meses, 7,63±4,3kg, 16,9±11,1% e 6,6±5,0%. A análise de subgrupos mostrou melhores resultados no subgrupo submetido à coagulação com plasma de argônio (APC) prévio à SET (p < 0,0001). A metanálise incluindo 15 desses estudos mostrou resultados concordantes e confirmou a superioridade estatística da SET+APC em comparação à SET isolada. Três estudos descreveram sutura de espessura superficial (SEP) com PAP média de 3,0±3,8kg, 4,4±0,07kg e 3,7±7,4 kg em 3, 6 e 12 meses, respectivamente. No seguimento de curto, médio e longo prazo, a SET proporcionou resultados superiores em relação à SEP (p < 0,05). Dois artigos descreveram APC isolada com PAP média de 15,4±2,0 kg e 15,4±9,1kg em 3 e 6 meses. Nenhum estudo relatando escleroterapia satisfez os critérios de elegibilidade. Conclusões: A sutura de espessura total é efetiva no tratamento do reganho de peso pós-DGYR. A realização de APC antes da sutura parece resultar em maior perda de peso. Estudos comparativos são necessários para confirmar nossos resultados. A sutura de espessura total relaciona-se com melhores resultados em comparação à sutura de espessura superficial. Poucos estudos avaliam adequadamente a eficácia de outras técnicas endoscópicas / Introduction: Roux-en-Y Gastric Bypass (RYGB) is the most commonly performed bariatric procedure. Despite its high efficacy, some patients regain part of their lost weight. Several endoscopic therapies have been introduced as alternatives to treat weight regain but most of the articles are relatively small with unclear long-term data. Aim: To systematically assess the efficacy of endoscopic therapies for weight regain after RYGB. Methods: We searched MEDLINE, EMBASE, Scopus, Web of Science, Cochrane, OVID, CINAHL/EBSCo, LILACS/Bireme and gray literature. Primary outcomes were absolute weight loss (AWL), excess weight loss (EWL) and total body weight loss (TBWL). Results: Thirty-two studies were included in qualitative analysis. Twenty-six articles enrolling 1148 patients described fullthickness (FT) endoscopic suturing and pooled AWL, EWL and TBWL at 3 months were 8.5±2.9kgs, 21.6±9.3% and 7.3±2.6%, respectively. At 6 months, they were 8.6±3.5kg, 23.7±12.3% and 8.0±3.9%. At 12 months, they were 7.63±4.3kg, 16.9±11.1% and 6.6±5.0%. Subgroup analysis showed that all outcomes were significantly higher in the group with FT suturing combined with argon plasma coagulation (APC) (p < 0.0001). Meta-analysis including 15 FT studies showed greater results and confirmed the significant superiority of FT-APC compared to FT alone. Three studies described superficial-thickness suturing with pooled AWL of 3.0±3.8kg, 4.4±0.07kg and 3.7±7.4kg at 3, 6 and 12 months, respectively. At short, mid and long-term follow-up, FT suturing provided better outcomes compared to ST (p < 0.05). Two articles described APC alone with mean AWL of 15.4±2.0kg and 15.4±9.1kg at 3 and 6 months. No study describing sclerotherapy fulfilled eligibility criteria. Conclusions: Full-thickness suturing is effective at treating weight regain after RYGB. Performing APC prior to suturing seems to result in greater weight loss. Head-to-head studies are needed to confirm our results. Full-thickness suturing lead to greater outcomes compared to superficial thickness suturing. Few studies adequately assess effectiveness of other endoscopic techniques
284

How to Realize a Septotomy of the Gastrointestinal Tract Through Natural Orifices,Without Incision ?

Huberland, Francois 25 May 2021 (has links) (PDF)
Gastrointestinal (GI) septa are pathological entities whereby a wall of tissue is present in the GItract, resulting in symptoms such as dysphagia and regurgitation. They can be associated withconditions such as esophageal diverticula or upper gastrointestinal duplication, or post-surgicalcomplications such as candy cane syndrome. Current treatments involve interventions by eitherhighly skilled endoscopists or invasive surgery. We suggest the use of compression anastomosis toachieve endoscopic septotomy, relieving the patients of their symptoms. Compression anastomosisusing rings, clips, magnets, and wires or rubber bands (though not named as such for these last two)has previously been described in the literature. We propose the use of a combination of MagneticCompression Anastomosis (MCA) and what we have defined as Wire Compression Cutting (WCC),both involving progressive pressure application to induce ischemia, necrosis, inflammation, andfibrosis with regeneration. This PhD thesis describes the development of a novel medical devicedesigned to achieve the aforementioned process, from initial conception to detailed constructionby a specialized company, based on clinical and technical requirements defined in collaborationwith physicians and from latest regulations. This device, the MAgnetic Gastrointestinal UniversalSeptotome (MAGUS), consists of two magnetic boxes linked by a self-retractable wire. The wire isactivated by a spring coil system located inside the two magnetic boxes. This MAGUS MagneticDevice (MMD) is designed to be used with the MAGUS Delivery System (MDS), a catheter to whichit is attached, enabling the physician to mobilize each magnet independently during the procedure.To assess that the MAGUS meets the technical requirements of the procedure, and to mitigateagainst all possible risks that were identified through Failure Mode and Effects Analysis, verificationtests were performed in combination with animal testing. Clinical trials started in February 2020at Erasme Hospital with good preliminary results. Finally, to make the procedure more accessiblefor less experienced physicians, future improvements on the delivery catheter and procedure areproposed. / En gastroentérologie, un septum est défini comme une paroi de tissu séparant deux cavités. Ce typede structure peut être la cause de symptômes tels que de la dysphasie ou des vomissements. Il estcausé soit par des pathologies, comme les diverticules ou duplications de l’oesophage, soit par descomplications chirurgicales, comme le syndrome dit du "candy cane". Le traitement classique estla chirurgie mais celle-ci est liée à un haut taux de mortalité et morbidité. Ces dernières années,de nouvelles techniques endoscopiques ont été proposées, mais la plupart de celles-ci nécessitentl’intervention de médecins très expérimentés. Le travail développé dans cette thèse propose d’utiliserle concept d’anastomose par compression pour réaliser une découpe de ce septum. L’anastomosepar compression a été abondamment traitée dans la littérature. Cette compression est réalisée pardes anneaux, des clips, des aimants, des élastiques, ou du fil. Afin de réaliser cette septotomie,nous proposons donc de combiner l’anastomose par compression magnétique et ce que nous avonsappelé la découpe par compression par fil (Wire Compression Cutting), qui consiste à appliquer unepression, pour induire de l’ischémie, de la nécrose, de l’inflammation, et enfin de la régénérationcombinée à de la fibrose. Deux cahiers des charges, l’un clinique et l’autre technique, ont été réalisés;ceux-ci se basent sur la littérature sur le sujet, des échanges avec des médecins, et les normeset régulation actuellement d’application. Dans la suite du travail, le développement techniquedu MAGUS (MAgnetic Gastrointestinal Universal Septotome) est décrit, de l’idée à la premièreutilisation sur patients. Ce dispositif permet de réaliser cette compression, à l’aide de deux aimantsreliés par un fil rétractable. Cette solution épurée permet ainsi de découper différentes tailles deseptum, en une seule endoscopie, et sans incisions, réduisant le risque de perforation. Le "MAGUSMagnetic Device" a été conçu avec son outil dédié, le "MAGUS Delivery System", permettant defaciliter la mise en place du dispositif par endoscopie. Afin de vérifier que les caractéristiquestechniques définies au préalable sont bien remplies, et de réduire les dangers identifiés par uneanalyse de risque, des tests de vérifications ont été réalisés, en parallèle d’essais de faisabilité sur descochons. Les premières études cliniques ont commencé en février 2020 à l’Hôpital Erasme, donnantdes résultats préliminaires très encourageants. Ces premiers traitements ont notamment permisde prouver la faisabilité de la découpe par compression par fil. Ce travail est conclu en proposantdes améliorations pour le dispositif de pose, afin de faciliter sa prise en main, ainsi que de futuresnouvelles applications cliniques. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished
285

Location and Tracking for Ultra-WideBand In-Body Communications in Medical Applications

Barbi, Martina 13 December 2019 (has links)
[ES] La cápsula inalámbrica de endoscopia (WCE) es una tecnología notable y atractiva adoptada en el sector biomédico hace varios años. WCE proporciona una tecnología de imagen inalámbrica no invasiva que permite a los especialistas reconocer y diagnosticar enfermedades que afectan todo el tracto gastrointestinal. Aunque los médicos pueden recibir imágenes claras de anomalías en el tracto gastrointestinal, no tienen información sobre sus exacta ubicación. La localización precisa de los trastornos detectados es crucial para el posterior procedimiento de extracción mediante cirugía. Actualmente, la banda de frecuencia asignada para aplicaciones de cápsula endoscópica es la banda MICS (402-405 MHz) que ofrece una velocidad de datos de hasta 500 kbps, insuciente para transmitir imágenes de alta calidad. Recientemente, la tecnología de banda ultra ancha (UWB) ha estado atrayendo atención como posible candidato para la próxima generación de cápsula endoscópica. Las ventajas de UWB incluyen arquitecturas de transceptor simples que permiten bajo consumo de potencia, baja interferencia a otros sistemas y amplio ancho de banda que resulta en comunicaciones a una velocidad de datos más alta. En esta disertación, el rendimiento de las técnicas de localización de WCE basadas en radiofrecuencia (RF) se investiga a través de simulaciones software, medidas experimentales de laboratorio que involucran fantomas homogéneos y heterogéneos y a través de experimentos in vivo que constituyen el escenario de prueba más realista. La tecnología UWB (3.1-10.6 GHz) se considera como interfaz de comunicación para aplicaciones de cápsula endoscópica. En tal escenario, el transmisor inalámbrico está ubicado en el tracto gastrointestinal, mientras que uno o más receptores inalámbricos están ubicados sobre la supercie del cuerpo. El enfoque basado en la potencia recibida (RSS) se investiga principalmente debido a su simplicidad de implementación y menos sensibilidad a las limitaciones de ancho de banda. Se analiza el impacto de la posición y del número de receptores seleccionados en la precisión de la localización. Finalmente, se desarrolla una interfaz gráfica de usuario (GUI) para visualizar los resultados de la localización en tres dimensiones (3D) obtenidos mediante las medidas in vivo. / [CAT] La càpsula sense fil d'endoscòpia (WCE) és una tecnologia notable i atractiva adoptada en el sector biomèdic fa diversos anys. La WCE proporciona una tecnologia d'imatge sense fil no invasiva que permet als especialistes reconéixer i diagnosticar malalties que afecten tot el tracte gastrointestinal. Encara que els metges poden rebre imatges clares d'anomalies en el tracte gastrointestinal, no tenen informació sobre les seues exacta ubicació. La localització precisa dels trastorns detectats és crucial per al posterior procediment d'extracció mitjançant cirurgia. Actualment, la banda de freqüència assignada per a aplicacions de càpsula endoscòpica és la banda MICS (402-405 MHz) que ofereix una velocitat de dades de fins a 500 kbps, insucient per a transmetre imatges d'alta qualitat. Recentment, la tecnologia de banda ultra ampla (UWB) ha estat atraient atenció com a possible candidata per a la pròxima generació de càpsula endoscòpica. Els avantatges d' UWB inclouen arquitectures de transceptor simples que permeten un baix consum de potència, baixa interferència amb altres sistemes i una gran amplada de banda que resulta en comunicacions a una velocitat de dades més alta. En aquesta dissertació, el rendiment de les tècniques de localització de WCE basades en radiofrequència (RF) s'investiga a través de simulacions amb programari, mesures experimentals de laboratori que involucren fantomes homogenis i heterogenis i a través d'experiments in vivo que constitueixen l'escenari de prova més realista. La tecnologia UWB (3.1-10.6 GHz) es considera com a interfície de comunicació per a aplicacions de càpsula endoscòpica. En tal escenari, el transmissor sense fil està situat en el tracte gastrointestinal, mentre que un o més receptors sense fils estan situats sobre la superfície del cos. L'enfocament basat en la potència rebuda (RSS) s'investiga principalment a causa de la seua simplicitat d'implementació i menys sensibilitat a les limitacions d'amplada de banda. S'analitza l'impacte de la posició i del numere de receptors seleccionats en la precisió de la localització. Finalment, es desenvolupa una interfície gràca d'usuari (GUI) per a visualitzar els resultats de la localització en tres dimensions (3D) obtinguts mitjançant les mesures in vivo. / [EN] Wireless Capsule Endoscopy (WCE) is a remarkable and attractive technology adopted in the biomedical sector several years ago. It provides a non-invasive wireless imaging technology for the entire gastrointestinal (GI) tract. WCE allows specialists to recognize and diagnose diseases affecting the whole GI tract. Although physicians can receive clear pictures of abnormalities in the GI tract, they have no information about their exact location. Precise localization of the detected disorders is crucial for the subsequent removal procedure by surgery. Currently, the frequency band allocated for capsule endoscopy applications is the MICS band (402-405 MHz). This band offers data rate up to 500 kbps, which is insufficient to transmit high quality images. Recently, Ultrawideband (UWB) technology has been attracting attention as potential candidate for next-generation WCE systems. The advantages of UWB include simple transceiver architectures enabling low power consumption, low interference to other systems and wide bandwidth resulting in communications at higher data rate. In this dissertation, performance of WCE localization techniques based on Radio Frequency (RF) information are investigated through software simulations, experimental laboratory measurements involving homogeneous and heterogeneous phantom models and in vivo experiments which constitute the most realistic testing scenario. Ultra-Wideband technology (3.1-10.6 GHz) is considered as communication interface in Wireless Capsule Endoscopy. In such scenario, the wireless transmitter is located in the gastrointestinal track while one or more wireless receivers are located over the surface of the body. Received Signal Strength (RSS)-based approach is mainly explored due to its implementation simplicity and less sensitivity to bandwidth limitations. Impact of the position and the number of selected receivers on the localization accuracy is analyzed. Finally, a graphical user interface (GUI) is developed to visualize the three-dimensional (3D) localization results obtained through in vivo measurements. / Barbi, M. (2019). Location and Tracking for Ultra-WideBand In-Body Communications in Medical Applications [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/132874 / TESIS
286

Otoskopische und histologische Untersuchungen des Pferdeohres im Rahmen der Anpassung objektiver Hörfunktionsdiagnostik: Otoscopic and histological examinations of the equine acoustic organ in line with the adaption of objective diagnostic audiometric testing

Blanke, Annemarie 03 February 2015 (has links)
In der veterinärmedizinischen Wissenschaft spielt das equine akustische Organ sowie dessen Erkrankungen und Funktionsstörungen bislang eine stark untergeordnete Rolle. Mangelnde Visualisierungs- und Untersuchungsmöglichkeiten, geringe Patienten- Compliance sowie fehlende Referenzen erschweren die Diagnose aurikulärer Erkrankungen (SARGENT et al. 2006; SOMMERAUER et al. 2012). Das übergeordnete langfristige Ziel dieser Forschungsarbeit ist es, humanmedizinische objektive audiometrische Messtechnik an das Pferdeohr anzupassen. Von speziellem Interesse ist dabei die Messung otoakustischer Emissionen zur objektiven Überprüfung der Innenohrfunktion. Die grundlegende Voraussetzung jeglicher Messungen und Adaptierungen ist zunächst die otoskopische Kontrolle des externen Gehörkanales und Trommelfelles. So können die Messung behindernde Faktoren, beispielsweise ein hoher Verschmutzungsgrad oder Fremdkörper im externen Gehörkanal, ausgeschlossen werden. Mit Hilfe herkömmlicher Videobronchoskope oder Videogastroskope (Durchmesser von 7 mm bzw. 9 mm) und der Anwendung eines standardisierten Protokolls konnten im Rahmen der Basisstudie die externen Gehörkanäle und Trommelfelle von 38 sedierten Pferden bilateral endoskopisch untersucht werden. Aus praktischer Sicht ist dabei hervorzuheben, dass die bislang obligatorische Leitungsanästhesie der Ohrnerven und das damit verbundene Risiko einer Fazialisparese vollständig umgangen werden konnte. Im Zuge dieses optimierten Verfahrens wurden physiologische und pathologische endoskopische Referenzen des externen Gehörkanales und Trommelfelles erstellt. Pathologische otoskopische Befunde (z.B. Tympanosklerose) sowie mangelnde veterinärmedizinische Fachliteratur verdeutlichen den Bedarf der histologischen Aufarbeitung des equinen akustischen Organs. Im Rahmen der Folgestudie wurden die Ohren von zehn Schlachtpferden für die detaillierte histologische Aufarbeitung herangezogen. Die Ergebnissedieser Arbeit beschreiben und verbildlichen erstmalig das vollständige equine akustische Organ. Im Folgenden sind nun die wesentlichen Ergebnisse der Basis- und Folgestudie zusammengefasst. Der physiologische kartilaginöse externe Gehörkanal ist pigmentiert, mit Haaren sowie mit cerumenproduzierenden Talg- und Schweißdrüsen ausgekleidet. Im Vergleich zum ossären externen Gehörkanal weist der kartilaginöse Anteil einen deutlich höheren Verschmutzungsgrad auf. Der Übergang zwischen dem kartilaginösen und ossären äußeren Gehörgang ist histologisch gekennzeichnet durch einen abrupten Wechsel zu einem unpigmentierten, haarlosen und drüsenfreien mehrschichtig verhornten Epithel. Endoskopisch ist dieser Übergang anhand kranzartig angeordneter beigefarbener Keratinschuppen erkennbar, welche Produkte des Selbstreinigungsmechanismus des knöchernen Gehörganges darstellen. Letzterer besitzt eine rund-ovale Form, ein trockenes zartrosafarbenes Epithel mit konzentrischen Keratinringen und schwach durchscheinender Gefäßzeichnung. Das physiologische equine Trommelfell stellt sich endoskopisch als eine klar in ihre Bestandteile (Pars tensa, Pars flaccida, Stria mallearis) differenzierte semitransparente Membran ohne positiven Lichtreflex dar. Auf der Grundlage der etablierten physiologischen Referenzen konnten pathologische Befunde bei sieben Pferden (vier Pferde mit Aural Plaques, drei Pferde mit Otitis externa) nachgewiesen werden. Zu den typischen Kennzeichen einer Otitis externa zählen die Schwellung und Rötung des ossären Epithels, das Verstreichen der konzentrischen Keratinringe und/oder die Ablösung der schützenden Keratinschicht im ossären Gehörkanal sowie ein positiver Lichtreflex im Bereich des Trommelfelles. Bei einem der an Otitis externa erkrankten Pferde konnte ein möglicher Zusammenhang zu einer Temporohyoidosteoarthropathie (THO) hergestellt werden. Darüber hinaus konnte bei zwei weiteren Pferden erstmalig eine Tympanosklerose diagnostiziert werden. Die Resultate dieser Dissertation liefern die Grundlage für weitere Forschungsansätze auf dem Gebiet des equinen akustischen Organs. Die Ohrendoskopie am stehenden sedierten Pferd ist eine praktikable, schonende sowie diagnostisch wertvolle Untersuchungsmöglichkeit. Sie sollte insbesondere bei der Abklärung einer THO, Fazialisparese, Vestibularsyndrom, Headshaking, Kopfscheue, parasitären Infektionen oder bei Kopftraumata zum Einsatz kommen. Die Ohrendoskopie ist zudem der Ausgangspunkt für die Anpassung und Anwendung humanmedizinischer audiometrischer Messsonden an das Pferdeohr. Die gewonnenen histologischen Erkenntnisse bilden die Basis für weiterführende Untersuchungen hinsichtlich angeborener oder erworbener Mittel- und Innenohrerkrankungen, welche Einfluss auf die Messung der otoakustischen Emissionen haben.:Inhaltsverzeichnis Einleitung ...................................................................................................................... 1 Literaturübersicht .......................................................................................................... 4 Anatomie des equinen akustischen Organs ................................................................. 4 8 Danksagung 2.4.1 2.4.2 2.4.3 2.4.4 Otoskopie ........................................................................................................ 10 Tympanometrie ............................................................................................... 11 Messung otoakustischer Emissionen (OAE) ................................................... 12 Hirnstammaudiometrie (BERA) ....................................................................... 14 Äußeres Ohr...................................................................................................... 4 Mittelohr ............................................................................................................ 4 Innenohr ............................................................................................................ 5 Hörbahn ............................................................................................................ 7 Gleichgewichtsbahn .......................................................................................... 7 2.1.1 2.1.2 2.1.3 2.1.4 2.1.5 Physiologie des Hörvorganges ..................................................................................... 8 Physiologie des Vestibularorgans................................................................................. 9 Untersuchungsmethoden des akustischen Organs .................................................... 10 Ergebnisse .................................................................................................................. 15 Publikation 1: Endoscopic findings of the external ear canal in a group of clinically normal horses and horses with head shaking or vestibular disease .......................... 15 Publikation 2: Histological Study of the External, Middle and Inner Ear of Horses .... 25 Diskussion .................................................................................................................. 44 Otoskopie.................................................................................................................... 45 Der physiologische equine externe Gehörkanal und das Trommelfell ....................... 46 Pathologische Befunde des equinen externen Gehörkanales und Trommelfelles ..... 48 Histologie des equinen akustischen Organs............................................................... 50 Diagnostische Möglichkeiten - OAE ........................................................................... 51 Zusammenfassung ..................................................................................................... 53 Summary .................................................................................................................... 55 Literaturverzeichnis..................................................................................................... 57 Anhang ....................................................................................................................... 64 / The equine acoustic organ, including its diseases and disorders, still plays a minor role in veterinary science. Due to insufficient visualization and examination equipment, little patient compliance and sparse references the diagnosis of auricular diseases is rather difficult (SARGENT et al. 2006; SOMMERAUER et al. 2012). The overall aim of this research project is to adapt human objective audiometric testing devices onto the equine acoustic organ. Particularly, the measurement of so-called otoacoustic emissions is of importance for an objective evaluation of the inner ear function. The otoscopic examination of the external ear canal and tympanic membrane is the fundamental precondition for the adaption of probes and every audiometric testing. Circumstances that may prevent us from having successful measurements, like a high degree of ceruminous and cellular debris or even foreign bodies within the external ear canal, can be identified and eliminated by otoscopy. By the use of common veterinary videobronchoscopes or videogastroscopes (calibre 7 mm/9 mm) the external ear canal and tympanic membrane of 38 standing sedated horses were bilaterally examined following a standardized protocol. Special emphasis should be placed on the fact that the obligatory local nerve block anaesthesia of the auricular nerves and the associated risk of a facial nerve paralysis were completely eliminated. With the help of this simplified procedure physiological and pathological references could be established. Pathological findings and a lack of relevant veterinary literature prompted us to take a closer look at histological aspects of the equine acoustic organ. In this context, the ears of ten slaughter horses were histologically examined in detail. The results of this follow-up study describe and illustrate the complete histology of the equine acoustic organ for the first time. In the following the essential results of the basic- and follow-up study are summarized. The physiological cartilaginous external ear canal is pigmented and contains hair, as well as ceruminous and sebaceous glands. In comparison to the osseous external ear canal, the cartilaginous part has higher degree of ceruminous and cellular debris. The intersection between both- the cartilaginous and osseous portion- is histologically characterized by an abrupt change to a non-pigmented, hairless, aglandular keratinized stratified squamous epithelium. Endoscopically, the intersection can be identified by a rim of beige keratin scales, which are products of the self-cleaning mechanism of the osseous epithelium. The osseous ear canal is round to oval shaped and lined with pale pink coloured epithelium that contains concentric keratin formations and visible capillary drawing. The physiological equine tympanic membrane is endoscopically characterized by a well-differentiated semi- transparent membrane, which shows no positive light reflex. On basis of the established physiological references pathological changes were found in seven horses (four horses with aural plaques, three horses with otitis externa). Typical sings of otitis externa were swelling and reddening of the osseous epithelium, the loss of the concentric keratin layer formation and/or detachment of the protective osseous keratin layer, as well as a positive light reflex on the tympanic membrane. In one diseased horse a possible correlation between the Otitis externa and severe temporohyoid osteoarthropathy (THO) could be revealed. Additionally, tympanosclerotic changes within two equine eardrums could be visualized for the first time. The results of this study provide a basis for further research on the equine acoustic organ. The otoscopic examination in standing sedated horses is a viable, safe, easy and quick to perform beneficial diagnostic procedure for a complete work-up of ear-related diseases, such as THO, facial nerve paralysis, vestibular disease, head shaking, parasitic infections or head trauma. In addition, the otoscopic examination is a basic requirement for the adaption and the use of human audiometric measuring probes in equine ears. The results obtained in the histological study can be employed as references for further research on equine congenital and acquired middle and inner ear diseases, which can influence the measurement results of otoacoustic emissions.:Inhaltsverzeichnis Einleitung ...................................................................................................................... 1 Literaturübersicht .......................................................................................................... 4 Anatomie des equinen akustischen Organs ................................................................. 4 8 Danksagung 2.4.1 2.4.2 2.4.3 2.4.4 Otoskopie ........................................................................................................ 10 Tympanometrie ............................................................................................... 11 Messung otoakustischer Emissionen (OAE) ................................................... 12 Hirnstammaudiometrie (BERA) ....................................................................... 14 Äußeres Ohr...................................................................................................... 4 Mittelohr ............................................................................................................ 4 Innenohr ............................................................................................................ 5 Hörbahn ............................................................................................................ 7 Gleichgewichtsbahn .......................................................................................... 7 2.1.1 2.1.2 2.1.3 2.1.4 2.1.5 Physiologie des Hörvorganges ..................................................................................... 8 Physiologie des Vestibularorgans................................................................................. 9 Untersuchungsmethoden des akustischen Organs .................................................... 10 Ergebnisse .................................................................................................................. 15 Publikation 1: Endoscopic findings of the external ear canal in a group of clinically normal horses and horses with head shaking or vestibular disease .......................... 15 Publikation 2: Histological Study of the External, Middle and Inner Ear of Horses .... 25 Diskussion .................................................................................................................. 44 Otoskopie.................................................................................................................... 45 Der physiologische equine externe Gehörkanal und das Trommelfell ....................... 46 Pathologische Befunde des equinen externen Gehörkanales und Trommelfelles ..... 48 Histologie des equinen akustischen Organs............................................................... 50 Diagnostische Möglichkeiten - OAE ........................................................................... 51 Zusammenfassung ..................................................................................................... 53 Summary .................................................................................................................... 55 Literaturverzeichnis..................................................................................................... 57 Anhang ....................................................................................................................... 64
287

Využití optických endoskopických metod v diagnostice slizničních nádorů hlavy a krku / Application of Optical Endoscopic Methods in Diagnostics of Head and Neck Mucosal Tumors

Šatanková, Jana January 2021 (has links)
Diagnosis of laryngeal and hypopharyngeal cancer is often in advanced stages of cancer, resulting in elimination of the possibility of treatment with the least mutilating effect for the patient. The huge progamination. ress in diagnostic process of mucosal tumors of the head and neck has been started with the development of new optical endoscopic imaging methods that are able to visualize initiating discrete mucosal changes with pathological vascularization easier and more accurately. The aim of this dissertation is to evaluate the benefit of Narrow Band Imaging (NBI), especially in the differentation of benign, precancerous and malignant changes in three groups of patients, it means in preoperative diagnostics in outpatient department (group I), during the endoscopic surgery (group II) and also in follow-up of patients after curative radiotherapy (group III). The vascular changes within the observed lesion or in close contact with the laryngeal/hypopharyngeal lesion were classified according to two classifications (Ni and Arens) and subsequently correlated with the histopathological results. The dissertation confirmed that NBI plays a key role in early detection of precancerous and malignant changes, in discrimination between benign and malignant vascular patterns with statistical significance. We...
288

Thorakoskopische Untersuchungen am stehenden Rind

Dorn, Katja 10 December 2013 (has links)
Zielsetzung: In dieser Studie wurde an 15 gesunden Rindern die Methode der Thorakoskopie erprobt mit dem Ziel, eine Grundlage für den weiteren Einsatz dieses Verfahrens am bovinen Thorax zu schaffen. Im Mittelpunkt standen die Entwicklung einer geeigneten Untersuchungstechnik und die Beschreibung der endoskopisch dargestellten, im Pleuraspalt gelegenen Organe sowie möglicher pathologischer Befunde. Weiterhin galt es Komplikationen zu ermitteln und anhand der Erfahrungen aus diesem Versuch Indikationen für den Einsatz dieses minimal-invasiven Verfahrens beim Rind zu formulieren. Methodik: Alle Tiere wurden einer links- und rechtsseitigen Thorakoskopie jeweils mit und ohne intrapleurale Insufflation von Kohlenstoffdioxid über einen interkostalen Zugang unterzogen. Im Rahmen des Versuches fanden folglich vier Thorakoskopien je Rind und insgesamt 60 Thorakoskopien mit einer Wartezeit von 24 Stunden zwischen den einzelnen Untersuchungen statt. Die Untersuchungen erfolgten am im Zwangsstand fixierten, lokal anästhesierten Tier. Der endoskopische Zugang lag stets auf Höhe des Tuber coxae und variierte vom 8. bis zum 10. Interkostalraum. Nach interkostaler Schnittinzision wurde eine Zitzenkanüle bis in den Pleuraspalt vorgeschoben. Der spontane Einstrom von Raumluft in das Cavum pleurae führte zum Teilkollaps des ipsilateralen Lungenflügels. Die Kanüle wurde durch eine Trokar-Hülsen-Einheit ersetzt und die Hülse stellte nach Entfernung des Trokars den Zugang für die Optik. Je Hemithorax wurde die Untersuchungszeit auf 20 Minuten festgelegt. Sie begann im kranialen Pleuraspalt, wurde über (dorso)-kranial, (dorso)-medial, (dorso)-kaudal, ventrokaudal und ventral fortgeführt und endete mit ventrokranial ausgerichteter Optik. Ergebnisse: Die meisten im Cavum pleurae gelegenen Organe konnten ohne die Insufflation von CO2 ausreichend adspiziert werden. Während der links- und rechtsseitigen Thorakoskopien gelang die Adspektion großer Bereiche der Pleura costalis mit den Mm. intercostales interni sowie den Aa. et Vv. intercostales dorsales, Anteile der Lungenflügel und des Ligamentum pulmonale, der Aorta thoracica, des thorakalen Ösophagus, des M. longus colli, von Lymphknoten des Lc. thoracicum dorsale sowie der Lnn. mediastinales caudales, der Pars thoracica des Truncus sympathicus und des Truncus vagalis dorsalis des N. vagus. Des Weiteren konnten der M. psoas major, Anteile des Diaphragmas und der V. phrenica cranialis, der Hiatus aorticus, der Arcus lumbocostalis sowie unregelmäßig die A. et V. bronchoesophagea adspiziert werden. Die Untersuchung des rechten kranialen Pleuraspaltes war mit Einschränkungen behaftet und spiegelte sich in einer reduzierten Darstellung der sympathische Nervenfasern aus dem Ggl. cervicothoracicum, des Truncus costocervicalis dextra sowie der V. costocervicalis dextra wider. Linksseitig war die Betrachtung dieser Organe bzw. der korrespondierenden linksseitig angelegten Organe regelmäßig möglich. Weiterhin gelang während der linksseitigen Untersuchung die Adspektion des Ln. tracheobronchalis sinister, des Truncus brachiocephalicus sowie der V. azygos sinistra. Rechtsseitig konnte die V. azygos dextra stets adspiziert werden. Die Darstellung des Ductus thoracicus erfolgte nur bei einem der untersuchten Rinder infolge einer pathologischen Kompression. Während der Untersuchungen unter passivem Lungenkollaps war das Perikard nur bei einer rechtsseitigen Thorakoskopie zu sehen. Die Zweituntersuchungen des ipsilateralen Pleuraspaltes fanden während der Insufflation von CO2 bis zu einem Überdruck von 5 mm Hg statt. Dies sollte einen stärkeren Lungenkollaps bewirken und damit die Sicht auf intrapleural gelegene Organe verbessern. Während der Insufflation waren beidseits größere Anteile der Rippen und des Zwerchfells sowie das Perikard linksseitig bei drei Rindern und rechtsseitig bei einem Rind darstellbar. Postoperative Röntgenaufnahmen dienten dem Ausschluss des Vorhandenseins eines ipsi- oder kontralateralen Pneumothorax. Schlussfolgerung: Die Studie zeigt, dass Thorakoskopien an stehenden, gesunden Rindern sicher und komplikationsarm durchzuführen sind. Die beschriebene, minimal-invasive Technik stellt eine wertvolle, zusätzliche Methode zur tierschonenden Abklärung intrathorakaler Erkrankungen beim Rind dar. Der diagnostische, palliative oder therapeutische Nutzen muss in weiterführenden Untersuchungen ermittelt werden. / Objective: A study on 15 healthy cows was conducted to prove the thoracoscopic technique with the aim to establish a basis for further application of this procedure on cattle. Focus was on developing an adequate examination technique, displaying and describing of physical as well as pathological findings on intrathoracic organs examined endoscopically. Furthermore perioperative complications and indications of this minimally invasive method on cattle should be presented. Methods: The animals underwent a left and right side thoracoscopy under passive lung collapse and under insufflation of CO2. Therefore four thoracoscopies at each cow and a total of 60 thoracoscopies were performed with a waiting time of 24 hours between each examination. The cows were restrained in a stock and locally anesthetized. The endoscopic portal was lined up horizontally with the level of the ventral margin of the coxal tuber, at the point where the local anaesthetic had been injected and varied between the eighth and the tenth intercostal space. After a vertical stab incision through the skin and subcutaneous tissues a blunt stainless teat cannula was introduced into the pleural space. At this point air streamed spontaneously into the pleural space following by an ipsilateral lung collapse. The teat cannula was then removed and replaced by a sharp guarded trocar. After that the trocar was removed and the endoscope was passed through the remaining cannula. The time assessment for examination of each thorax was 20 minutes, started in the cranial pleural space, was continued in the (dorso)-cranial, (dorso)-medial, (dorso)-caudal, ventrocaudal und ventral direction and ended with ventrocranially aligned optic. Results: Most of the intrathoracic organs were seen without additional CO2 insufflation. During left and right side thoracoscopies large parts of the costal pleura, the internal intercostal muscles, the dorsal intercostal veins and arteries, parts of the lungs and the pulmonary ligament, the thoracic aorta, the thoracic part of the esophagus and the longus colli muscle, caudal mediastinal lymph nodes and lymph nodes associated with the dorsal thoracic lymph center, the thoracic part of the sympathic trunk and the dorsal vagus nerve were seen. Furthermore the psoas major muscle, parts of the diaphragm and the cranial phrenic vein, the aortic hiatus, the lumbocostal arch and intermittently the broncho-esophageal artery and vein could be identified. There were some constraints during right side thoracoscopy of the cranial pleural space which caused a limited view at the sympathic nerve fibres associated with the cervicothoracic ganglion, the right costocervical trunk and the right costocervical vein. At the left side these organs, the corresponding left side organs respectively, were constantly seen. Moreover during the exam at the left pleural space the left tracheobronchial lymph node, the brachiocephalic trunk and the left azygos could be well identified. During right side thoracoscopy the right azygos vein was always visible. In one case the presentation of the thoracic duct succeeded as a result of its pathological compression. During examination under passive lung collapse the pericard was visualized in one cow during right side thoracoscopy. The second thoracoscopies of the ipsilateral pleural space were conducted during insufflation of CO2 with a pressure of 5 mm Hg. A stronger lung collapse should result during insufflation with an enhanced view of the organs located intrapleurally. During insufflation at both sides larger parts of the ribs and diaphragm as well as the pericard on the left side at three cattle and on the right side at one cattle could be seen. Postoperative radiographies ensured the absence of an ipsi- or contralateral pneumothorax. Conclusion: This study shows that thoracoscopies on standing healthy cattle could be safely performed without major perioperative complications or side effects. The described minimally invasive procedure is a valuable, gentle and additional method to diagnose intrathoracic diseases in cattle. The use of thoracoscopy as diagnostic tool, for curative and palliative therapy should be identified in further studies.
289

Die navigierte, schablonengeführte und endoskopisch-assistierte Entfernung von unteren dritten Molaren über einen okklusalen Zugang / Navigated, Guided And Endoscopically Assisted Removal Of Mandibular Third Molars Using An Occlusal Approach

Streit, David 28 October 2019 (has links)
No description available.
290

Performance of the FIB-4 index in esophageal varices screening in patients with the diagnosis of liver cirrhosis / Desempeñ o del índice FIB-4 en el despistaje de vá rices esofá gicas en pacientes con el diagnóstico de cirrosis hepá tica

Cá Lamo-Guzmá N, Bernardo, De Vinatea-Serrano, Luis, Piscoya, Alejandro, Segura, Eddy R. 01 January 2020 (has links)
INTRODUCTION: The diagnosis of esophageal varices in cirrhotic patients is made by the upper gastrointestinal endoscopy. Multiple non-invasive predictors have been studied for the diag-nosis of esophageal varices. The objective of this study is to testthe FIB4 index as screening of esophageal varices in patients with liver cirrhosis. MATERIALS AND METHODS: A cross-sectional analytic study was developed in four national hospital using hepatic cirrhosis patient's medi-cal files. We assessed the information using univariate and bivariate analysis, sensitivity, speci-ficity, predictive positive and negative value, the positive and negative likelihood ratio calcu-lation of the esophageal varices screening and its size. We built ROC curve for every analysis group. RESULTS: The study included 289 liver cirrhosis patients. Most of the patients were male (54.33%). 77.85% patients had esophageal varices. The distribution of varices was 19.03%, 35.99% and 22.84% for large, medium and small varices, respectively. In the FIB-4 index analysis for the presence of varices, it was found a sensitivity of 81.3%, specificity of 37.5% (AUC: 0.57). The calculation for variceal size showed a sensitivity of 81.8%, specificity of 23.9% (AUC: 0.50). In the analysis of FIB-4 index for prophylaxis groups was found a sensitivity of 81.8% and a specificity of 28.5% (AUC: 0.54). CONCLUSIONS: The FIB-4 index has no good performance in the screening for the presence of esophageal varices and its size in liver cirrhosis patients. / Revisión por pares

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