Dissertations / Theses on the topic 'Flexible endoscopy'

Introduction: Oesophagogastroduodenoscopy is the investigation of choice to identify mucosal lesions of the upper gastrointestinal tract, but it is poorly tolerated by patients. A simple non-invasive technique to image the upper gastrointestinal tract, which could be made widely available, would be beneficial to patients. Capsule endoscopy is well tolerated by patients but the stomach has proved difficult to visualise accurately with capsule technology due to its’ capacious nature and mucosal folds, which can obscure pathology. MiroCam Navi (Intromedic Ltd, Seoul, Korea) is a capsule endoscope containing a small amount of magnetic material which has been made available with a handheld magnet which might allow a degree of control. This body of work aims to address whether this new technology could be a feasible alternative to conventional flexible endoscopy of the stomach. Methods: Four studies were conducted to test this research question. The first explores the feasibility of magnetically assisted capsule endoscopy of the stomach and operator learning curve in an ex vivo porcine model. This was followed by a randomised, blinded trial comparing magnetically assisted capsule endoscopy to conventional flexible endoscopy in ex vivo porcine stomach models. Subsequently a prospective, single centre randomised controlled trial in humans examined whether magnetically assisted capsule endoscopy could enhance conventional small bowel capsule endoscopy by reducing gastric transit time. Finally a blinded comparison of diagnostic yield of magnetically assisted capsule endoscopy compared to oesophagogastroduodenoscopy was performed in patients with recurrent or refractory iron deficiency anaemia. Results: In the first study all stomach tags were identified in 87.2% of examinations and a learning curve was demonstrated (mean examination times for the first 23 and second 23 procedures 10.28 and 6.26 minutes respectively (p<0.001). In the second study the difference in sensitivities between oesophagogastroduodenoscopy and conventional flexible endoscopy for detecting beads within an ex vivo porcine stomach model was 1.11 (95% CI 0.06, 28.26) proving magnetically assisted capsule endoscopy to be non-inferior to flexible endoscopy. In the first human study, although there was no significant difference in gastric transit time or capsule endoscopy completion rate between the two groups (p=0.12 and p=0.39 respectively), the time to first pyloric image was significantly shorter in the intervention group (p=0.03) suggesting that magnetic control hastens capsular transit to the gastric antrum but cannot impact upon duodenal passage. In the last study, a total of 38 pathological findings were identified in this comparative study of magnetically assisted capsule endoscopy and conventional endoscopy. Of these, 16 were detected at both procedures, while flexible endoscopy identified 14 additional lesions not seen at magnetically assisted capsule endoscopy and magnetically assisted capsule endoscopy detected 8 abnormalities not seen by oesophagogastroduodenoscopy. No adverse events occurred in either of the human trials. Finally magnetically steerable capsule endoscopy induced less procedural pain, discomfort and distress than oesophagogastroduodenoscopy (p=0.0009, p=0.001 and p=0.006 respectively). Conclusion: Magnetically assisted capsule endoscopy is safe, well tolerated and a viable alternative to conventional endoscopy. Further research to develop and improve this new procedure is recommended.

In a near future, the computation power will be widely used in endoscopy rooms. It will enable the augmented reality already implemented in some surgery. Before reaching this, a preliminary step is the development of a 3D reconstruction endoscope. In addition to that, endoscopists suffer from a lack of quantitative data to evaluate dimensions and distances, notably for the polyp size measurement.

In this thesis, a contribution to more a robust 3D reconstruction endoscopic device is proposed. Structured light technique is used and implemented using a diffractive optical element. Two patterns are developed and compared: the first is based on the spatial-neighbourhood coding strategy, the second on the direct-coding strategy. The latter is implemented on a diffractive optical element and used in an endoscopic 3D reconstruction device. It is tested in several conditions and shows excellent quantitative results but the robustness against bad visual conditions (occlusions, liquids, specular reflection,) must be improved.

Based on this technology, an endoscopic ruler is developed. It is dedicated to answer endoscopists lack of measurement system. The pattern is simplified to a single line to be more robust. Quantitative data show a sub-pixel accuracy and the device is robust in all tested cases. The system has then been validated with a gastroenterologist to measure polyps. Compared to literature in this field, this device performs better and is more accurate.
Doctorat en Sciences de l'ingénieur
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The technological developments seen in recent years have facilitated remarkable progress in the field of flexible gastrointestinal (GI) endoscopy. Smaller high-resolution charge-coupled devices (CCDs) have facilitated the manufacture of ultrathin (UT) (<6mm) endoscopes, while the introduction of device assisted enteroscopy (balloon-assisted and spiral enteroscopy) has allowed endoscopists to access the deep small bowel (SB) without the need for recourse to major surgery. Furthermore, the application of double-balloon colonoscopy (DBC) has shown promise to improve outcomes in patients with 'technically difficult' colons. Although these 3 types of innovative endoscopic technologies all share the potential capacity to enhance minimally invasive patient care, research into their optimal role and effectiveness (particularly within UK clinical practice) remains limited. This thesis has examined the potential role of this selection of advanced flexible GI endoscopic technologies for the enhancement of minimally invasive patient care. The first study evaluated transnasal upper GI endoscopy in the UK and confirmed that within this clinical paradigm, transnasal endoscopy using UT endoscopes, is a feasible, effective and more acceptable alternative to patients than conventional oral upper GI endoscopy. The next series of studies were dedicated to device assisted enteroscopy (DBE in particular) and showed that DBE is capable of providing a safe and effective, minimally invasive alternative to major surgery in selected cases. A comparison of spiral enteroscopy as an alternative to DBE, showed that spiral enteroscopy (in its current, manual form), appears to be inferior to DBE in its ability to facilitate deep enteroscopy. The final study evaluated technically difficult colonoscopy and included the development and validation of a score for technical difficulty which may in the future be applied to routine clinical practice. This study also highlighted the usefulness of DBC as a potentially more effective tool than conventional colonoscopy for technically difficult cases.

Hyperspectral (HS) imaging combines spectral measurement of a pixel with 2D imaging technology. It is capable to provide a series of images containing both spectral and spatial information, and has been widely used in medical domain. However, most researches on medical HS imaging are regarding ex-vivo biopsy or skin and oral mucosa. The study on HS imaging regarding in-vivo disease lags far behind. In this thesis, we developed a novel flexible HS endoscope system. It is capable to obtain a series of HS images in vivo in a non-contact way among the wavelength range of 405 – 665 nm. After a lot of time-consuming modifying and debugging work, this new system has high stability and convenience to be applied in clinic now. We evaluated this system in clinic. First, we got ethics approval for clinical trials. Then, we obtained HS images regarding gastrointestinal (GI) diseases inside patients using this system. As far as we know, this type of in-vivo image data has not been reported in previous literatures. Thus using these HS images, we built a database for GI mucosa. Next, we analyzed some typical HS images tentatively. The method of Recursive Divergence is implemented to extract valuable and diagnostic information from these HS images. The results prove the effect and applicability of this new HS endoscope system, which has shown the great potential to be used as a platform and guidance for further medical studies. To further apply the analysis results in clinic, we propose a novel Adaptive Narrow-Band Imaging (ANBI) method based on band selection of HS images of a specific type of disease. It is expected that the new technique has higher accuracy, sensitivity, and specificity compared to conventional Narrow-Band Imaging (NBI) technique. In this thesis, we also discuss the future direction of the system improvement. Especially, to improve light intensity and signal-noise-ratio of HS images in wide-field view, we propose a new imaging method using broad- and overlapped-band filters. Although this method only performs greatly on the foundation of accurate image registration, we hope to apply it in our system in the future.

Orientador: Konstantin Georgiev Kostov
Resumo: Nos últimos anos, tem intensificado o emprego de plasmas em pressão atmosférica para diferentes aplicações. Com o desenvolvimento dos jatos de plasma em pressão atmosférica, alguns tratamentos precisos, como no campo biomédico ou em específicos processamentos de superfícies, tornaram-se mais frequentes. No entanto, a aplicação de plasma à objetos irregulares, dentro de tubos ou mesmo dentro de órgãos ocos é limitada quando se utilizam configurações convencionais de jatos de plasma. Portanto, essas limitações podem ser superadas com o desenvolvimento de jatos de plasma alongados ou gerados remotamente. Neste trabalho, duas configurações de jato de plasma longo visando diferentes campos de aplicação foram aperfeiçoadas e caracterizadas. Inicialmente foi desenvolvido um jato de plasma endoscópico (plasma endoscope) operando em configuração de descarga por barreira dielétrica (DBD) com dimensões milimétricas, versátil ao acoplamento em endoscópios típicos. Este jato de plasma pode operar com hélio ou neônio e conta com um canal externo e concêntrico de gás que permite a introdução de uma cortina de gás eletronegativo ao redor da pluma de plasma. A cortina de proteção a gás preserva a forma do jato de plasma quando operado dentro de cavidades fechadas. As dificuldades advindas do desenvolvimento deste foram investigadas quando diferentes gases foram testados como cortina de proteção dele, dentre estes, o dióxido de carbono se mostrou uma boa opção evitando a formação de descargas ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The use of atmospheric pressure plasmas for different purposes has increased in recent years. With the development of atmospheric pressure plasma jets, some precise treatments such as in the biomedical field or specific surface processing became more often. However, the delivery of plasma to irregular shaped objects, inside tubes or even hollow organs is limited with the use of conventional plasma jet configurations. Therefore, those limitations can be surpassed with the development of elongated or remotely generated plasma jets. In this work, two extended plasma jet configurations aiming at different application fields were further developed and characterized. Firstly, an endoscopic plasma jet (plasma endoscope) operating with a dielectric barrier discharge (DBD) configuration in millimeter dimensions that can be coupled to a typical endoscope was developed. This plasma jet can operate with helium or neon and counts with an external concentric shielding gas channel that provides the introduction of an electronegative gas curtain around the plasma plume. The shielding gas allows the preservation of the plasma jet shape when operated inside closed cavities. The construction difficulties arisen from the use of different feed and shielding gases were explored. Carbon dioxide was proven to be a good option for the curtain gas around the plasma plume avoiding the formation of parasitic discharges inside the shielding gas tube and the endoscopic housing. When operated with neon, th... (Complete abstract click electronic access below)
Doutor

Les endoscopes utilisés en gastro-entérologie ne permettent pas d’obtenir une réelle chirurgie dans le tube digestif en passant par les voies naturelles. Cette thèse a pour ambition de pallier ce manquement grâce au développement d’une plate-forme de triangulation universelle. Cette plateforme donne la possibilité au gastro-entérologue d’augmenter de manière significative ses possibilités thérapeutiques en lui permettant de réaliser des actes chirurgicaux de base tels que “soulever-couper” et “suturer” les tissus. Ces actes ne peuvent être réalisés qu’extrêmement difficilement avec les endoscopes conventionnels. Ils constituent pourtant les éléments essentiels en vue de traiter l’obésité morbide ou le traitement du reflux gastro-oesophagien par les voies naturelles. La caractéristique principale de la plate-forme développée dans cette thèse est son universalité lui permettant une utilisation avec pratiquement n’importe quel type d’endoscope et outils thérapeutiques existants sur le marché. La plate-forme a obtenu le marquage CE. Des études cliniques ont été réalisées avec cet instrument dans le cadre du traitement de l’obésité. Cette thèse comprend également une méthodologie de conception pour des guidages flexibles utilisés dans le domaine médical. Cette méthodologie basée sur l’élaboration d’abaques théoriques permet, d’une part, à partir des desiderata du médecin, d’identifier les paramètres externes (rigidité, longueur.) d’un guidage flexible et ce peu importe le type de guidage utilisé et, d’autre part, de déduire les paramètres internes associés à ces paramètres externes pour un type de guidage particulier: un élastomère renforcé par un ressort hélicoïdal. La méthode a été appliquée `a posteriori `a la plate-forme de triangulation et donne, dans ce cas, de bons résultats. Flexible endoscopes used in gastro-enterology do not allowed a real surgery in the gastrointestinal tract passing through natural orifices. This thesis aimed to overcome these limitations by developing a universal triangulation platform. This platform allows the gastro-enterologist to significantly increase his therapeutic possibilities by enabling him to perform basic surgical procedures such as "lifting-cutting" and "suturing" the tissues. These procedures can only be performed with extreme difficulty with conventional endoscopes. They are, however, the essential elements for the treatment of morbid obesity or gastroesophageal reflux through natural orifice. The main feature of the platform developed in this thesis is its universality allowing it to be used with any type of endoscopes and existing tools available on the market. The platform has obtained the CE marking. Clinical studies have been conducted with this instrument for treatment of obesity. This thesis includes also a design methodology for flexible guides used in the medical field. This methodology, based on the elaboration of theoretical abacuses, allows, firstly, from the physician's specifications, to identify the external parameters (rigidity, length .) of the flexible guide regardless of the type of the used guide. Secondly, it allows to determine the internal parameters associated with these external parameters for a particular type of guide: an elastomer reinforced by a helical spring. The method was applied a posteriori to the triangulation platform and, in this case, gives good results.
Doctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished

Colonoscopy provides a minimally invasive tool for examining and treating the colon without surgery, but current endoscope designs still cause a degree of pain and injury to the colon wall. The most common colonoscopies are long tubes inserted through the rectum, with locomotion actuators, fiber optic lights, cameras, and biopsy tools on the distal end. The stiffness required to support these tools makes it difficult for the scopes to navigate the twisted path of the colon without damaging the inside wall of the colon or distorting its shape. In addition, little is known about how sharp and forceful endoscopes can be without accidentally cutting into tissue during navigation. In order to solve the requirements of stiffness (to support tools) and flexibility (to navigate turns), we expanded on a design by Zehel et al. [49], who proposed surrounding a flexible endoscope with an external exoskeleton structure, with controllable stiffness. The exoskeleton structure is comprised of rigid, articulating tubular units, which are stiffened or relaxed by four control cables. The stiffened or locked exoskeleton structure aids navigation and provides stability for the endoscope when it protrudes beyond the exoskeleton structure for examination and procedures. This research determined the design requirements of such an exoskeleton structure and simulated its behavior in a sigmoid colon model. To predict just how pointed an endoscope can be without damaging tissue under a given force, we extrapolated a strength model of the descending colon from published stress-strain curves of human colon tissue. Next we analyzed how friction, cable forces, and unit angles interact to hold the exoskeleton structure in a locked position. By creating two- and three-dimensional models of the exoskeleton structure, we optimized the dimensions of the units of an exoskeleton structure (diameter, thickness, and leg angle) and cable holders ( cable attachment location) to achieve the turns of the sigmoid colon, while still remaining lockable. Models also predicted the loss of force over the exoskeleton structure due to curving, further determining the required cable angles and friction between units. Finally we determined how the stiffness of the endoscope stem affected locking ability and wear inside the exoskeleton structure.
Ph. D.

La microscopie multiphotonique est un outil essentiel d’investigation en biologie cellulaire et tissulaire. Son extension à l’endoscopie est l’objet d’intenses efforts de recherche pour des applications en neurosciences (imagerie cérébrale du petit animal) ou en clinique (diagnostic précoce, aide à la biopsie). Ce manuscrit porte sur le développement d’un endomicroscope multiphotonique présentant des performances inédites. Ce dispositif est alimenté par un oscillateur titane-saphir standard. Vient ensuite un module de pré-compensation des distorsions linéaires et non linéaires se produisant dans la fibre endoscopique. Ce module permet d’obtenir des impulsions compressées de 39 fs à la sortie d’une fibre microstructurée air-silice innovante à double gaine de 5 mètres de long qui est optimisée pour l’excitation multiphotonique (cœur central de 3,4 µm à maintien de polarisation) et la collection du signal produit par les cibles biologiques. A l’extrémité de la fibre, on trouve une sonde endoscopique, de 2,2 mm de diamètre pour 37 mm de long, composée d’un micro-scanner à fibre optique et d’un micro-objectif achromatique de distance de travail supérieure à 400 µm. La résolution spatiale de l’appareil vaut 0,83 µm et l’acquisition se fait en simultané sur deux canaux spectraux à 8 images/s. L’appareil a permis l’enregistrement d’images in vivo sans marquage des tubules et de la capsule rénale, respectivement par fluorescence à deux photons des flavines et par génération de second harmonique du collagène, avec 30 mW sur les tissus et jusqu’à 300 µm sous la surface de l’organe
Multiphoton microscopy is an essential investigative tool in cell and tissue biology. Its extension to endoscopy is the subject of intensive research for applications in neuroscience (brain imaging of small animals) or clinical (early diagnosis, help for biopsy). This manuscript focuses on the development of an endomicroscope with multiphoton unprecedented performance. This device is powered by a standard titanium-sapphire oscillator. Then comes a pre-compensation module of linear and nonlinear distortions occurring in the endoscopic fiber. This module provides compressed pulses of 39 fs at the direct output of 5 meters long innovative double-clad air-silica microstructured fiber which is optimized for multiphoton excitation (polarization maintaining central core of 3.4 µm) and the collection of the signal produced by biological targets. At the end of the fiber, there is an endoscopic probe, 2.2 mm in diameter and 37 mm long, composed of a micro fiber scanning system and an achromatic micro-objective with a working distance greater than 400 µm. The spatial resolution of the device is 0.83 µm and the acquisition is done simultaneously on two spectral channels at 8 frames/s. The device has recorded in vivo images without label of the tubules and the renal capsule, respectively by two-photon excitation fluorescence of flavins and second harmonic generation of collagen, with 30 mW on the tissues and 300 µm below the surface of the organ

Les techniques de reconstruction de formes tridimensionnelles sont très largement utilisées dans de nombreux domaines, et notamment dans le domaine industriel ou médical. Et dans ces domaines, les techniques de mesure sans contact sont particulièrement étudiées, principalement parce qu'elles permettent de ne pas détériorer l'objet mesuré. Ce travail de thèse se place donc dans ce contexte et plus particulièrement dans le cas des dispositifs endoscopiques de mesure tridimensionnelle de surface par moyen optique. Dans le domaine médical, ce type d'instrument peut être appliqué à la coloscopie 3D ou à la chirurgie mini-invasive pour la détection de forme en surface de tissus biologiques. Dans cette thèse ce sont plus particulièrement les méthodes à base de stéréovision active ou passive, qui vont être étudiées et intégrées dans un dispositif miniaturisé. Différents modes de mesure vont être intégrés simultanément dans un unique instrument miniaturisé afin de permettre d'augmenter les performances de mesure : l'instrument peut adapter son principe de mesure à la texture de l'objet ou également à l'orientation des surfaces mesurées et plus généralement au contexte de la mesure. Ce travail de thèse est donc basé sur une étude algorithmique et instrumentale d'intégration de ces différents modes de mesure dans un unique instrument endoscopique miniaturisé. L'étude des modes de mesure par stéréovision a été réalisée en trois phases. Tout d'abord, c'est l'influence de l'orientation de la surface des objets mesurés dans un cas de stéréovision active qui est analysé. Puis une technique de basculement entre les voies de projection et d'acquisition du système de stéréovision active par actionnement bistable est proposé, ce qui permet d'adapter la mesure à l'orientation des surfaces à mesurer. Enfin, l'étude est orientée vers la possibilité de basculer d'un mode de stéréovision active vers un mode de stéréovision passive, toujours par actionnement bistable, le mode de stéréovision passive étant particulièrement adapté aux objets fortement texturés. Ainsi, trois modes de mesure sont réalisés dans ce nouveau système : deux modes de stéréovision active (avec inversion des voies de capture et de projection) et un mode de stéréovision passive. Pour réaliser la reconstruction tridimensionnelle, deux méthodes actives (par décalage de phase et par transformation de Fourier) et une méthode passive sont étudiées. Différentes performances de mesure sont obtenues selon les méthodes sélectionnées : un résultat de mesure plus précis est obtenu par les méthodes à. décalage de phase, une vitesse de mesure plus élevée est obtenu par les méthodes à transformée de Fourier ou par les méthodes passives. Le développement instrumental est également décrit dans cette thèse. Après modélisation optique et conception mécanique du système de mesure, un prototype de l'instrument endoscopique est fabriqué avec divers équipements spécifiques, tels qu'un DMD (Digital Micromirror Device), des guides d'images et des actionneurs électromagnétiques bistables. La validation expérimentale de la mesure tridimensionnelle est réalisée essentiellement sur objets mécaniques (du type mesure de détails sur pièce de monnaie), les deux méthodes actives et la méthode passives sont ainsi testées et confrontées. Enfin, une mesure sur un colon artificiel est réalisée par ce système pour se placer dans un contexte applicatif médical
The techniques of three dimensional shapes reconstruction are widely used in many fields, particularly in the industrial or medical field. And in these areas, non-contact measurement techniques are particularly studied, mainly because they don't damage the measured object. This work therefore falls within this context and in particular in the case of endoscopic devices of surface coordinate measuring by optical methods. ln the medical field, this type of instrument can be applied to 3D colonoscopy or minimally invasive surgery to the surface in the form of biological tissues. In this thesis, methods based on active or passive stereo vision are the principle, which will be studied and integrated into a miniaturized device. Different measurement modes will be incorporated simultaneously into a single miniaturized instrument to help increase measurement performance: the instrument can adjust its measurement principle to the texture of the object or also to the orientation of measured surfaces more generally to the context of the measurement. This thesis is based on an algorithmic study and instrumental integration of these different measurement modes into a single miniaturized endoscopic instrument. The study of the measurement modes stereovision was conducted in three phases. First, it is the influence of the orientation of the measured objects' surface in a case of active stereovision being analyzed. And a technique of switching between the projection and acquisition in an active stereovision system by bistable actuation is proposed, which allows to adapt the measurement to the orientation of the measured surfaces. Finally, the study is oriented towards the ability to switch from one active stereovision mode to one passive stereovision mode, always by bistable actuator operation, the passive stereovision mode is particularly suitable for highly textured objects. Thus, three measurement modes are made in the new system: two modes of active stereovision (reversing capture and projection channels) and a mode of passive stereovision. To achieve three-dimensional reconstruction, two active methods (phase shift and Fourier Transform) and a passive method are studied. Different performance measurements are obtained according to methods selected: a more accurate measuring result is obtained by the phase shift methods; a high measurement speed is obtained by the Fourier transform methods or by passive methods. The instrumental development is also described in this thesis. After optical modeling and mechanical design of the measuring system, a prototype of the endoscopic instrument is manufactured with various specific devices such as a DMD (Digital Micromirror Deviee),images guides and bistable electromagnetic actuators. The experimental validation of the three-dimensional measurement is performed mainly on mechanical objects (such as details measurement on a coin), both active and passive method methods are well tested and compared. Finally, an artificial colon is measured by this system to be placed in a medical application context

Il manque actuellement aux médecins une nouvelle méthode qui rationalise le traitement peu invasif pour en faire des procédures à opérateur unique, assistées par une caractérisation précise des tissus in situ et en temps réel, en situation de prise de décisions dans la gestion du cancer colorectal. Une solution prometteuse à ce problème a été développée par l'équipe AVR (Automatique, Vision et Robotique) du laboratoire ICube, au sein de laquelle l'endoscope interventionnel flexible (fabriqué par Karl Storz) a été entièrement robotisé, permettant ainsi à un seul opérateur de télémanipuler indépendamment l'endoscope et deux instruments thérapeutiques insérables, grâce à unité de contrôle commune. Cependant, l'endoscope flexible assisté par robot est soumis aux mêmes limites de précision diagnostique que les systèmes d'endoscopie standards. Il a été démontré que l'OCT endoscopique présente un potentiel pour l'imagerie des troubles de la voie gastro-intestinale et pour la différenciation de tissus sains des tissus malades. Actuellement, l'OCT se limite à l'imagerie de l'œsophage humain, qui présente une géométrie simple et un accès facile. Ni l'OCT, ni l'endoscope robotisé ne peuvent résoudre à eux seuls les limites de la norme actuelle de soins pour la prise en charge d’un cancer du côlon. La combinaison de ces deux technologies et le développement d'une nouvelle plate-forme pour la détection et le traitement précoce du cancer constituent l'objet principal de cette thèse, avec la vision de développer une console d'imagerie OCT et une sonde de haute technologie intégrée à l'endoscope robotisé. Ce système permet d'obtenir des images de l'intérieur du gros intestin pour la caractérisation des tissus et l'assistance au traitement, permettant ainsi à un seul opérateur d'effectuer une intervention peu invasive en mode télémanipulation
There exists an unmet clinical need to provide doctors with a new method that streamlines minimally invasive endoscopic treatment of colorectal cancer to single operator procedures assisted by in-situ and real-time accurate tissue characterization for informed treatment decisions. A promising solution to this problem has been developed at the ICube laboratory, in which the flexible interventional endoscope (Karl Storz) was completely robotized, so allowing a single operator to independently telemanipulate the endoscope and two insertable therapeutic instruments with a joint control unit. However, the robot-assisted flexible endoscope is subject to the same diagnostic accuracy limitations as standard endoscopy systems. It has been demonstrated that endoscopic optical coherence tomography (OCT) has a good potential for imaging disorders in the gastrointestinal tract and differentiating healthy tissue from diseased. Neither OCT, nor the robotized endoscope can solve the limitations of current standard of care for colon cancer management alone. Combining these two technologies and developing a new platform for early detection and treatment of cancer is the main interest of this work, with the aim of developing a state-of-the-art OCT imaging console and probe integrated with the robotized endoscope. The capabilities of this new technology for imaging of the interior of the large intestine were tested in pre-clinical experiments showing potential for improvement in margin verification during minimally invasive endoscopic treatment in the telemanipulation mode

Connaître la position 3D d’instruments robotisés peut être très utile dans le contexte chirurgical. Nous proposons deux méthodes automatiques pour déduire la pose 3D d’un instrument avec une unique section pliable et équipé avec des marqueurs colorés, en utilisant uniquement les images fournies par la caméra monoculaire incorporée dans l'endoscope. Une méthode basée sur les graphes permet segmenter les marqueurs et leurs coins apparents sont extraits en détectant la transition de couleur le long des courbes de Bézier qui modélisent les points du bord. Ces primitives sont utilisées pour estimer la pose 3D de l'instrument en utilisant un modèle adaptatif qui prend en compte les jeux mécaniques du système. Pour éviter les limites de cette approche dérivants des incertitudes sur le modèle géométrique, la fonction image-position-3D peut être appris selon un ensemble d’entrainement. Deux techniques ont été étudiées et améliorées : réseau des fonctions à base radiale avec noyaux gaussiens et une régression localement pondérée. Les méthodes proposées sont validées sur une cellule expérimentale robotique et sur des séquences in-vivo
Knowing the 3D position of robotized instruments can be useful in surgical context for e.g. their automatic control or gesture guidance. We propose two methods to infer the 3D pose of a single bending section instrument equipped with colored markers using only the images provided by the monocular camera embedded in the endoscope. A graph-based method is used to segment the markers. Their corners are extracted by detecting color transitions along Bézier curves fitted on edge points. These features are used to estimate the 3D pose of the instrument using an adaptive model that takes into account the mechanical plays of the system. Since this method can be affected by model uncertainties, the image-to-3d function can be learned according to a training set. We opted for two techniques that have been improved : Radial Basis Function Network with Gaussian kernel and Locally Weighted Projection. The proposed methods are validated on a robotic experimental cell and in in-vivo sequences

La chirurgie abdominale par voie transluminale est une approche révolutionnaire qui consiste à introduire les instruments dans la cavité abdominale par un orifice naturel du patient (tel que la bouche, l'anus, le vagin ou l'urètre). Cette nouvelle technique chirurgicale porte la dénomination NOTES (Natural Orifice Transluminal Endoscopic Surgery) dans la littérature médicale. Les gastroscopes utilisés aujourd'hui pour effectuer les opérations ont une partie distale active orientable selon deux directions orthogonales à l'aide de deux molettes présentes sur la poignée et offre un retour visuel par la caméra embarquée dans l'extrémité distale de l'endoscope. L'interface de commande peu intuitive et les informations visuelles limitées font du gastroscope un outil difficile à manier. Afin d'apporter une assistance robotique aux praticiens lors d'interventions transluminales, nous avons développé un système de positionnement automatique de la tête flexible de l'endoscope. L'objectif est de réaliser une liaison virtuelle entre la tête et une structure anatomique d'intérêt malgré les mouvements physiologiques, l'interaction des instruments avec l'environnement et le mouvement d'enfoncement manuel de l'endoscope. Ce système s'appuie sur la motorisation d'un endoscope flexible classique, où nous avons remplacé les molettes de la poignée par deux moteurs pour permettre la commande numérique des deux degrés de liberté de la tête flexible. La liaison virtuelle « tête-structure anatomique » est alors réalisée sur la base d'un schéma d'asservissement visuel 2D
Transluminal surgery, also called NOTES (Natural Orifice Transluminal Endoscopic Surgery), consists of accessing the peritoneal cavity by passing through a natural orifice and then to make an opening in an inner wall to accomplish treatments. Conventional flexible endoscopes used nowadays to perform these procedures have a distal bending tip controlled by two navigation wheels located on the handle. They also provide a visual feedback from an optical system (CCD camera) embedded at the tip of the endoscope. These tools are quite awkward for the surgeons as the control interface is non intuitive and the visibility is poor. In order to supply a robotic assistance to the praticians during flexible endoscopy interventions, we have developed an automated positioning system of the endoscope tip. The objective is to realize a virtual link between the tip of the endoscope and an anatomical target despite the physiological motions, the interaction of the instruments with the environment and the manually controlled forward/backward motion of the endoscope. The pratician can thereby focus on the manipulation of the endoscopic tools while the bending section compensate the occurring disturbances. The virtual link between the tip and the anatomical target is performed using a 2D visual servoing scheme in association with the selection of relevant visual features

The present dual field of view flexible colonoscope can provide both forward view and radial or backward view of the colon to improve detection of cancerous polyps. The colonoscope has its own illumination that illuminates the parts of the colon viewed by imaging optics. The optical system, limited only by the diffraction effects at the exit pupil over the entire visible spectrum, can provide high resolution and is suitable for color imaging. The flexible colonoscope has an on-board sensor at the proximal end of the colonoscope to improve resolution. The proximal end of colonoscope measures only 8 mm in diameter and 20 mm in length. The present colonoscope has the potential to be scaled down to as small as 6 mm inner diameter from the present 8 mm.

A laparoscopia é técnica cirúrgica minimamente invasiva na qual se utiliza um laparoscópio inserido por via transabdominal por onde é possível inspecionar visualmente a superfície das vísceras e do peritônio e realizar procedimentos cirúrgicos. Até o momento, a laparoscopia diagnóstica em equinos em estação através da fossa paralombar exige que sejam realizados dois procedimentos (um de cada lado do animal) para visualização significativa da cavidade peritoneal, além do uso de laparoscópio específico. Com o intuito de desenvolver a laparoscopia diagnóstica em equinos em estação por acesso único, foi desenvolvida uma cânula óptica com espiral sem trocarte de 60 cm de comprimento que tem o objetivo de promover maior segurança ao acesso laparoscópico (penetração radial sem trocarte e sob visualização) e sustentação ao endoscópio flexível para que seja possível realizar exploração significativa de ambos os hemisférios abdominais dorsais por apenas uma das fossas paralombares. Foram utilizados seis equinos adultos, sendo três machos e três fêmeas, submetidos a jejum alimentar de 24 a 30 horas. Amostras de sangue para realização de hemograma e dosagem de fibrinogênio foram obtidas no D-Pré, D4 e D7. Os equinos foram sedados com cloridrato de detomidina, seguido de bloqueio anestésico local com cloridrato de lidocaína infundida na musculatura e tecido subcutâneo do local de incisão no centro da fossa paralombar. O procedimento cirúrgico teve início com incisão cutânea de cerca de 2 cm de comprimento. As camadas musculares da região foram afastadas através da rotação da cânula em sentido horário e o afastamento dos tecidos foi acompanhado pelas imagens produzidas pelo endoscópio flexível e reproduzidas no monitor. Logo da perfuração do peritônio, foi iniciada a exploração da cavidade. Após a exploração do lado ipsilateral ao local de acesso, foi realizada a transposição do conjunto cânula/endoscópio ventralmente à porção caudal do cólon descendente seguida de exploração do lado contralateral. Terminado o exame, o conjunto foi removido através da rotação da cânula no sentido anti-horário e a incisão de pele foi suturada junto ao subcutâneo. A movimentação da cânula entre os órgãos abdominais mostrou-se segura, no entanto, em dois animais houve lesão iatrogênica ao baço, evidenciada por discreta hemorragia local. Foi possível a identificação da maioria das estruturas abdominais descritas na literatura por procedimento laparoscópico em equinos em estação pelo acesso único. Em cinco dos seis animais houve formação de enfisema subcutâneo adjacente às feridas cirúrgicas. Os parâmetros hematológicos dos animais mantiveram-se dentro dos limites estabelecidos para a espécie, com exceção dos leucócitos totais, neutrófilos segmentados e fibrinogênio que demonstraram pequenas variações. A abordagem proposta mostrou-se viável e tem o potencial de tornar o procedimento mais rápido, prático e seguro e menos invasivo e oneroso, fomentando a aplicação da laparoscopia diagnóstica na espécie equina.
Laparoscopy is a minimally invasive surgical technique by using a laparoscope inserted through the abdominal wall where it is visually possible to inspect visceral surfaces and peritoneum, and to perform surgical procedures. Up to now, diagnostic laparoscopy in standing horses through the paralumbar fossa requires two procedures to be performed (one on each side of the animal) in order to significantly see the peritoneal cavity, in addition of using specific laparoscope. With the purpose to develop a diagnostic laparoscopy in standing horses through a single access, a trocarless threaded visual cannula 60 cm length was designed with the aim to promote higher safety to laparoscopic access (radial penetration without trocar and under visualization), and support to a flexible endoscope so that a significant exploration of both dorsal abdominal hemispheres through only one of the paralumbar fossa is possible to perform. Six mature horses were used: three males and three females. Food was withheld for 24 to 30 hours before surgery. Blood samples to perform complete blood count and fibrinogen metering were obtained in D-Pre, D4, and D7. The horses were sedated with detomidine hydrochloride, followed by local anesthesia blockade with lidocaine hydrochloride infused in the muscle and subcutaneous tissue at the incision place in the center of the paralumbar fossa. The surgical procedure started with a skin incision of nearly 2 cm length. Muscle layers of the region were moved away through clockwise cannula rotation and the distancing of the tissues were followed by images produced by the flexible endoscope and played on the monitor. After the peritoneum perforation, the cavity exploration was started. After the ipsilateral side exploration to the access site, the transposing of the set cannula/endoscope was performed ventrally to the rear portion of the descending colon followed by the contralateral side exploration. When the examination was finished, the set was removed through counterclockwise cannula rotation and the skin incision was stitched to the subcutaneous. Moving the cannula among the abdominal organs was shown to be safe; however, spleen iatrogenic injury in two animals was highlighted by minor local hemorrhage. The majority of the abdominal structures described in the literature was possible to identify through the laparoscopic procedure in standing horses by single access. There was subcutaneous emphysema formation adjoining the surgical wounds in five of the six animals. The hematological parameters of the animals were kept in the limits established for the species, with exception of total leucocytes, segmented neutrophils and fibrinogen which showed small variations. The proposed approach was shown to be feasible and has the potential to make the procedure faster, more practical and safe and less invasive and expensive, fostering the diagnostic laparoscopy application in the equine species.

A técnica cirúrgica endoscópica transluminal por orifícios naturais (NOTES) tem por definição envolver a introdução de um endoscópio no interior da cavidade abdominal através de uma perfuração intencional de uma víscera (p.ex. estômago, reto, vagina) e realizar uma exploração e/ou operação intra-abdominal. A incisão cirúrgica realizada pela técnica de NOTES tem a vantagem de ser utilizada para a retirada da cavidade abdominal de espécimes (NOSE) reseccionadas através de uma laparoscopia padrão ou por NOTES. O presente estudo teve por objetivo verificar a viabilidade da cânula vaginal em realizar o acesso transvaginal para a cavidade abdominal através da técnica de NOTES transvaginal em éguas hígidas posicionadas em estação e avaliar o acesso vaginal como canal de extração de espécimes (NOSE) em éguas submetidas à ovariectomia laparoscópica via flanco. Foram utilizadas 6 éguas hígidas para ambos os procedimentos cirúrgicos. Os animais foram submetidos a jejum alimentar pré-cirúrgico de 24 à 30 horas. Para a sedação utilizou-se cloridrato de detomidina e cloridrato de lidocaína para execução da epidural baixa. A incisão vaginal foi realizada dorsal à cérvix na posição horária de 12 horas utilizando uma cânula vaginal de ponta romba rosqueada e realizada sob visualização indireta através do endoscópio flexível inserido dentro da cânula. A remoção dos ovários via vaginal ocorreu em quatro das seis éguas utilizadas no experimento. Das quatro éguas, três tiveram a necessidade do aumento manual da colpotomia para apreensão manual dos ovários intracavitária e sua remoção. Em dois animais os ovários tiveram de ser seccionados e removidos através do flanco pelo aumento da incisão do canal de trabalho laparoscópico. A execução cirúrgica do acesso à cavidade abdominal via transvaginal e a técnica de extração de espécimes por NOSE submetidas à ovariectomia laparoscópica via flanco é possível de ser realizada em éguas hígidas.
The technique of Natural Orifice Transluminal Endoscopic Surgery (NOTES), by definition, concerns the introduction of an endoscope in the abdominal cavity through an intentional perforation of a viscera (for ex., stomach, recto, vagina) and performs an intra-abdominal exploration and/or operation. The surgical incision performed through the NOTES technique has the benefit of being used to remove resected specimens (NOSE) from the abdominal cavity through a standard laparoscopy or through NOTES. The present study had the purpose to check the practicality of the vaginal cannula in performing transvaginal access to the abdominal cavity through the NOTES technique in standing healthy mares and assess the vaginal access as an canal extraction of specimens (NOSE) in mares subjected to laparoscopic ovariectomy. Six healthy mares were used for both surgical procedures. The food was withheld between 24 to 30 hours before surgery. They were sedated with detomidine hydrochloride and to perform the low epidural, lidocaine hydrochloride was used. The vaginal incision was performed dorsally to the cervix at 12 o’clock position using threaded round tip vaginal cannula and performed under indirect viewing through a flexible endoscope inserted in the cannula. The ovaries were removed through the vagina in four of the six mares used in the experiment. From the four mares, three were required to manually increase the colpotomy for manual intracavitary seizure of the ovaries and their removal. In two of the animals, the ovaries had to be cut and removed through the flank, increasing the incision of the laparoscopic working channel. The procedure to create the access to the abdominal cavity through the vagina to perform the NOTES technique and the specimen extraction technique through NOSE subjected to laparoscopic ovariectomy in healthy mares did not demonstrate high difficulties in its execution nor post-surgical complications, confirming the practicality of the two techniques in the equine species.

Les travaux exposés dans cette thèse traitent de la modélisation multiphysique et de la commande distribuée de structures flexibles actionnées à l’aide de polymères électro-actifs de type Ionic Polymer Metal Composite (IPMC). Dans un premier temps, nous proposons une formulation Hamiltonnienne à ports de l’actionneur IPMC afin de tenir compte des couplages multiphysiques et multiéchelles. Des multiplicateurs de Lagrange sont utilisés pour gérer les contraintes mécaniques apparaissant au sein de l’actionneur. La structure mécanique de la structure flexible est quant à elle modélisée en 1D à l’aide de modèles de poutres et en 2D à l’aide d’un modèle de coques fines. Dans un second temps, deux méthodes de discrétisation préservant la structure sont présentées et étendues aux systèmes Hamiltoniens à ports de dimension infinie avec dissipation et entrée distribuée. Le modèle de l’actionneur est validé expérimentalement à l’aide d’une discrétisation de type différences finies sur grilles en quinconces. Dans un troisième temps, nous développons sur un modèle simplifié de type corde vibrante, une loi de commande distribuée dans le domaine à l’aide de patches, permettant de modeler la fonction d’énergie globale du système et d’injecter de la dissipation
This thesis deals with the multiphysical modeling and the distributed control of flexible structures actuated by Ionic Polymer Metal Composite (IPMC) actuators. We firstly propose a model for the IPMC actuator using infinite dimensional port-Hamiltonian formulations in order to tackle the multiphysical and multiscale couplings. Lagrange multipliers are used to handle the mechanical constraints appearing in the actuator. The mechanical structure of the flexible structure is then modeled in 1D with beam models and in 2D with a thin shell model. Secondly, two structure preserving discretization methods are presented and extended to infinite dimensional dissipative port-Hamiltonian system with distributed input. The proposed IPMC actuator model is then discretized using the structure preserving finite differences method on staggered grids and validated on experimental data. Thirdly, we propose an in-domain distributed control law on a simplified model i.e. the vibrating string actuated with patches, that allows to shape the total energy of the system and to inject damping in order to stabilize the overall system with predefined performances

Sensory input from the laryngeal mucosa is vital for triggering protective airway reflexes. The laryngeal adductor reflex (LAR) is a brief vocal fold adductor reflex in response to stimulation of the laryngeal mucosa. Depressed LAR may lead to aspiration of foreign substances into the airway. Loss of laryngeal sensation has thus been considered as one of the risk factors associated with aspiration and airway complications in patients with dysphagia. Laryngeal sensation can be endoscopically tested by lightly and briefly touching a patient’s arytenoids or epiglottis with the tip of a flexible laryngoscope (the touch method). In a preliminary study, we endoscopically investigated the laryngeal sensation and swallowing ability of healthy adults and patients with dysphagia. The results indicated an association between sensory deficits as determined by the touch method and penetration/aspiration of trial boluses in both healthy adults and patients with dysphagia. However, the pressure applied to the larynx using this touch method might not be consistent, and the expected responses elicited by this method were uncertain. Study 1 of this dissertation investigated the variability in the pressure delivered by clinicians using the touch method. The study also reported on the types of various subject responses to the touches. The results revealed that there was a wide range of pressure levels exerted by examiners. This suggested the need for further research to establish the validity of this diagnostic tool. The study also showed that the LAR always occurred in response to touch in normal volunteers, suggesting that this technique may be quite sensitive at detecting sensory deficits in a person who does not exhibit an LAR in response to touch. Study 2 examined hospitalized patients with symptoms of dysphagia. The question of interest was whether an absent LAR in response to touch was associated with aspiration or pneumonia. No significant association was found between absent LAR and aspiration of food or liquid; however, a significant association was observed between absent LAR and the occurrence of pneumonia. The study indicated that the touch method has potential for predicting pneumonia in patients with swallowing problems.
2017-11-07T00:00:00Z

碩士
國立臺北科技大學
管理學院外國學生專班(IMBA)
107
ZA - Medical is a start-up guided by Zolzaya Altanbagana, graduate of the International Business Administration at the National Taipei University of Technology. The start-up is a young company that one want to make a difference in order to contribute to make the world more beautiful. This is done among others by the implementation of the by Kate Raworth Donut Economy thought. With the first innovation of the company, is deployed on the saving energy and water combined with a pursuit of honesty rewards for stakeholders. In addition, a contribution is made to patient safety during endoscopic interventions. The above comes directly from the moonshot from Zolzaya. This research brings the market from chart endoscopy and the problems that occur in that market. An endoscope is a snake-shaped camera that allows in the body of the human can be looked at. The endoscopes are used after use washed with tap water and chemicals in special washing machines. The water filter that is used ensures still too often for problems. Through the usual microfiltration (MF) modules or UV lamps to be replaced with a filtration technique called ultrafiltration (UF), the start-up ensures it is excluded that water bacteria from the pipe network on a washed endoscope can end.

This doctoral research is focused on overcoming problems in autonomous surgical procedures when instruments have to navigate towards the clinical target by accurate self-localization in the front of certain tissue and, simultaneously, to build a map of the luminal environment for medical diagnosis. Vision-based approaches using stable tissue texture are highly desirable for a wide range of applications. Optical Coherence Tomography (OCT) [1] is an imaging technique of great importance in biomedical optical applications. The backscattered light is measured of the internal structure of biological tissues to provide high resolution, axial and three-dimensional images of the sample. Endoscopic OCT catheter has been applied into cardiovascular, respiratory and digestive systems for imaging of internal structures. In gastroenterology, a balloon and capsule based catheters have been developed for imaging of the esophagus. Catheter-based imaging systems have limited Field of View (FoV), especially when considering OCT systems which emphasize more on the image resolution. For small lumens such as the vasculature and esophagus, volume reconstruction from one pull back scanning using an OCT system can be sufficient for accessing the entire lumen. However, for larger luminal environments as the colon or stomach, the link between reconstruction, robot planning and robot control needs to be established e.g. the link with robot control is needed in order to realize a certain scanning behavior, which would be necessary to make reconstruction efficient and accurate. This side-viewing catheter could be employed to actively follow the lumen wall with a robotic endoscope. The OCT augmented endoscope can provide more accurate navigation feedback for the control system. The robotic endoscope also has a camera in the distal part, which can perform a rough global navigation to aid the OCT system’s local scanning. In the local scanning process, ideally, the distance between the OCT probe and the tissue is controlled to be constant. This could keep the tissue always in the FoV of the OCT, especially for luminal tissue with a complex geometry like the colon. Another type of safe scanning mode could also be realized with contact between the OCT catheter and the colon tissue surface. In this case, a segmentation algorithm is required to provide real-time quantitative feedback about the contact or the distance. For volumetric reconstruction from the robotic scanning, computer vision and imaging processing techniques including incremental mapping or Structure from-Motion (SfM) can be deployed. The main aims could be divided into the following three: - Find an efficient configuration for robotic endoscope navigation. To achieve this task, the OCT images first need to be stabilized to improve its orientation accuracy. - Information perception for both diagnosis and navigation purpose. Tailor the machine learning based computer vision algorithm for side-viewing imaging modalities. - Design automatic scanning strategies for larger lumen environment with small FoV side-viewing probes, incorporate local navigation information with global navigation information.

abstract: The objective of this project was to evaluate human factors based cognitive aids on endoscope reprocessing. The project stems from recent failures in reprocessing (cleaning) endoscopes, contributing to the spread of harmful bacterial and viral agents between patients. Three themes were found to represent a majority of problems: 1) lack of visibility (parts and tools were difficult to identify), 2) high memory demands, and 3) insufficient user feedback. In an effort to improve completion rate and eliminate error, cognitive aids were designed utilizing human factors principles that would replace existing manufacturer visual aids. Then, a usability test was conducted, which compared the endoscope reprocessing performance of novices using the standard manufacturer-provided visual aids and the new cognitive aids. Participants successfully completed 87.1% of the reprocessing procedure in the experimental condition with the use of the cognitive aids, compared to 46.3% in the control condition using only existing support materials. Twenty-five of sixty subtasks showed significant improvement in completion rates. When given a cognitive aid designed with human factors principles, participants were able to more successfully complete the reprocessing task. This resulted in an endoscope that was more likely to be safe for patient use.
Dissertation/Thesis
M.S. Applied Psychology 2011

This dissertation investigated measures of pharyngeal residue as seen on flexible endoscopic evaluation of swallowing (FEES). Research in this area of deglutology has been stalled due to measurement problems. The particular aims of this project were to compare visual analog scale ratings to categorical ratings of residue on FEES, and to investigate various measurement aspects. METHODS: Speech language pathologists were asked to rate residue from 81 swallows on FEES that demonstrated a wide range of residue severity for thin liquid, applesauce, and cracker boluses. A total of 33 clinicians rated the amount of residue at the time point after the first swallow, twice in a randomized fashion: the first time on a visual analog scale (VAS) and the second time categorically on a five point Likert scale. The results were analyzed for (1) inter/intra-rater agreement, (2) correlations between ratings and residue severity for each rating method, and (3) clusters of ratings to better define the scales and their clinical significance. A total of 2,673 VAS ratings and 2,673 categorical ratings were collected. RESULTS: (1) Both inter- and intra-rater reliability met acceptable levels of agreement, although intra-rater reliability on VAS ratings were slightly higher (r=0.8–0.9) than categorical ratings (k=0.7–0.8). Expert ratings were not significantly different from other clinicians’ ratings for any severity of any of the 3 boluses. (2) Residue ratings fit best on a curvilinear model; a quadratic fit of the data significantly improved the r2 values for each bolus type. (3) An increased residue amount, rated on either the VAS or categorical scale, was significantly associated with worse penetration-aspiration scale scores, but no significant relationship was found between the two methods of residue ratings and measures of quality of life or diet. Novel computerized methods are proposed for future measurement pursuits. CONCLUSION: The results of this dissertation suggest that residue is best measured on a scale with unequal intervals, and clinicians can be reliable in rating overall amount of residue on FEES after the first swallow. Novel computerized measurement approaches are useful building blocks for future research. It is hoped that with better measurement will come better understanding of residue, its risks, and consequences.