Rozprawy doktorskie na temat „Traitement d'images – Médecine”
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Aurengo, André. "Analyse factorielle des séquences d'images en médecine nucléaire". Paris 11, 1989. http://www.theses.fr/1989PA112413.
Pełny tekst źródłaMagimel-Pelonnier, Vincent. "Traitement d'images : vers l'extraction automatique de paramètres : application à la cardiologie en médecine nucléaire". Bordeaux 1, 1985. http://www.theses.fr/1985BOR10528.
Pełny tekst źródłaSaint-Jean, Patrick. "Processus de production et d'expérimentation biologiques et médicales par l'analyse de texture prétopologique et la robotique de laboratoire". Paris 13, 1989. http://www.theses.fr/1989PA132023.
Pełny tekst źródłaMichoud, Edouard. "Analyse d'images dynamiques en biologie et médecine : applications à la microcirculation clinique et expérimentale". Université Joseph Fourier (Grenoble), 1990. http://www.theses.fr/1990GRE19002.
Pełny tekst źródłaCoste, Eric. "Reconstruction d'une arborescence spatiale à partir d'un nombre minimal de projections : application à l'angiographie numérisée". Lille 1, 1996. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/1996/50376-1996-204.pdf.
Pełny tekst źródłaProvent, Pierre. "Segmentation d'images par analyse statistique de textures : application aux images échocardiographiques". Paris 12, 1991. http://www.theses.fr/1991PA120049.
Pełny tekst źródłaPiedbois, Pascal. "Stratégies d'informatisation d'un service de cancérologie, et nouvelles approches du traitement graphique de l'information". Paris 12, 1994. http://www.theses.fr/1994PA120023.
Pełny tekst źródłaHannequin, Pascal. "Applications des méthodes statistiques d'analyse multivariée au traitement des séries d'images en médecine nucléaire et en microscopie électronique". Reims, 1989. http://www.theses.fr/1989REIMS006.
Pełny tekst źródłaDebon, Renaud. "Analyse d'images échographiques de loesophage, reconstruction 3D et interprétation". Rennes 1, 2005. http://www.theses.fr/2005REN1S196.
Pełny tekst źródłaThis work concerns the approach evaluations, which are oriented « knowledge based system » for medical images interpretation applied to esophagus echoendoscopy and the development of aid system for tumor staging. It's shown how the intelligent approaches (expert system and information fusion) can allow rationalizing the using of a priori knowledge. The pertinent extraction of anatomic structures, in our case, esophagus structure, becomes a natural application in the knowledge engineering. This extraction is based on the image segmentation. The required robustness for these algorithms impose the advanced architectures development allowing the compensation of low numerical content of these images. Three concrete examples are detailed : 2D extraction of the esophagus' interface, 3D extraction of the esophagus' interfaces and spatial following with 3D reconstruction of the aorta. Knowledge is represented by static or dynamical model (fuzzy, geometric or evidential models). The approach using the complementarities of probabilities and fuzzy logic to obtain presentation « exact » of knowledge a priori. Fuzzy models and statistic reality are synchronized by a knowledge base. It's shown that all components can be integrated in a coherent architecture hierarchically organized
Gautier, Laurent. "Aide à la ségmentation d'images par la théorie des croyances : application aux séquences d'images IRM du rachis lombaire". Littoral, 2001. http://www.theses.fr/2001DUNK0057.
Pełny tekst źródłaThe current need for the fusion of data in image processing results directly from the multiplication of the data available starting from or of the systems of medical imagery which are used jointly to observe a same phenomenon under different aspects. The problem, which we pose in fusion data, can be expressed like a problem of decision on the truth or the probability of a proposal being given one or more information resulting from a same sensor or sensors different. With regard to the applications, it is a question of taking into account the vague, incomplete and dubious aspect of the data learned on each sensor and the redundant, complementary and conflict aspect of the whole of information. The complex characteristics of the informative systems must be introduced into all the stages of a process of fusion, from the assumptions the decision. The general goal of the thesis is a contribution to the segmentation 2D of images by belief theory applied to the sequences of images by Magnetic Resonance Imagery (MRI) of the lumbar rachis. The medical objective, in the long term, is the total and local analysis curve of the spinal column for the study of its deformations 3D starting from sequences obtained by MRI. Within the framework of this work, we were interested at the first stage : the segmentation of the vertebrae. The use of the traditional methods of segmentation did not enable us to obtain the contour of the vertebrae on images MRI acquisited. We then decided to exploit the contribution of the methods of data fusion to help us in the validation of the points resulting from the segmentation by active contour. For that, we propose a generic diagram of fusion data within the framework of our application. It diagram must allow of exploit the data exit of different level of analyze (at level of pixel, at level of contour) for extract the information the more reliable and the more exact in a goal of assistance with segmentation, in order to take in account the effect of partial volume dependent with protocol of acquisition MRI. For the architecture of fusion suggested, based on the theory of beliefs, we tried to justify the choice : a priori knowledge ; frame of discernement ; model of representation ; parameters essential to the discrimination of the starting assumptions ; strategy of fusion, distributed or global ; decision criteria. We discuss the validity of the found results, of the prospects considered and we finish for example of computation result of deformation 3D spinal column and vertebra
Pescheloche, Michel. "Traitements graphiques informatisés : de nouveaux outils pour automatiser des évaluations dans le secteur santé". Paris 12, 1994. http://www.theses.fr/1994PA120028.
Pełny tekst źródłaDebreuve, Éric. "Segmentation par contours actifs en imagerie médicale dynamique : application en cardiologie nucléaire". Nice, 2000. https://tel.archives-ouvertes.fr/tel-00506987.
Pełny tekst źródłaComas, Laurent. "Modèles et algorithmes pour la scintigraphie cardiaque". Besançon, 2005. http://www.theses.fr/2005BESA2022.
Pełny tekst źródłaIn medicine, modeling is an essential step for the evaluation of the acquisition and reconstruction methods and image analysis. In the first part of this thesis, a bibliographical study of models was made. It allowed the selection of NCAT model for its qualities of realism and of flexibility for simulating myocardial single photon emission computerised tomography. This examination is used for evaluating perfusion and kinetics of the myocardium. In the second part, for the quantification, algorithms of image segmentation were developed in order to isolate the heart among the noise and the other tissues. In the third part, two applications were developed : acquisition defects, such as time tracer stability, were simulated and their impact on the reconstructed images was measured; an information compression algorithm, the Karhunen-Loeve transformation, was evaluated for its efficacy in detecting and quantifying serial changes in myocardial perfusion
Elie, Nicolas. "Contribution à l'étude du stroma des tumeurs ovariennes humaines, par traitement et analyse d'images numériques". Caen, 2003. http://www.theses.fr/2003CAEN4061.
Pełny tekst źródłaSebbahi, Ali. "Segmentation 2D et 3D par modèles déformables en imagerie cardio-vasculaire". Paris 12, 1995. http://www.theses.fr/1995PA120040.
Pełny tekst źródłaHaddad, Rana. "Un Modèle numérique anthropomorphique et dynamique du thorax respirant et du coeur battant". Lyon, INSA, 2007. http://theses.insa-lyon.fr/publication/2007ISAL0019/these.pdf.
Pełny tekst źródłaThis work presents an anatomical and functional numerical model of the breathing thorax and the beating heart issued from dynamic imaging. Anatomical and functional cardiac and thoracic images were acquired in Magnetic Resonance Imaging (MRI) during the same examination on healthy volunteers according to a pre-established protocol. These data were then processed to build the model. The anatomical model integrates the geometry of the 3D cardiac, vascular and thoracic structures: four cavities of the heart (left and right ventricles, left and right atria), the myocardium, the pericardial envelope, the vascular system (junction of the main principal veins and arteries, coronary network), the external contour of the thorax (including skin, fat and ribs), the interior contour of the thorax (muscles), the two lungs, the spine and spinal cord. The realistic deformation of this static anatomical model, according to the heart and thorax motions, relies on estimated motions of the anatomical structures over cardiac and respiratory cycles. The motion estimator is based on successive 3D non rigid registrations (free form deformations based on B-Spline basis functions) in cine MR sequences for the heart motion, and three respiratory gated frames for the thorax motion. The so obtained dynamical model is then virtually imaged by two simulators: the MRI simulator SIMRI (Creatis, Lyon) and the PET simulator SORTEO (CERMEP, Lyon), according to protocols similar to those used for acquiring the native images. The resulting model, composed of the anatomical structures, the dynamic model and the simulated images constitutes a digital reference model of the breathing thorax and the beating heart. Its qualitative and partly quantitative evaluation is presented. The principal characteristics of the proposed model with respect to the existing models are its richness of structures and information and its great coherence since the data used for the development of the model come from the same subject during the same examination. Such a model can constitute a basis for the evaluation of cardiac and thoracic image processing algorithms such as image segmentation, motion estimation or multimodality image registration. It could also be used for computer aided medical training, e. G. To practice surgical gestures
Göksu, Cemil. "AngioNavigation : contribution des environnements virtuels aux interventions endovasculaires assistées par ordinateur". Rennes 1, 2005. http://www.theses.fr/2005REN1S058.
Pełny tekst źródłaCapelle-Laizé, Anne-Sophie. "Segmentation d'images IRM multi-échos tridimensionnelles pour la détection des tumeurs cérébrales par la théorie de l'évidence". Poitiers, 2003. http://www.theses.fr/2003POIT2330.
Pełny tekst źródłaMagnetic resonance imaging is a grateful tool for observation of the human brain anatomy. In particular, the diversity of the parameters acquisition provides several views of the brain useful for the detection of brain tumours. In the framework of the help of diagnosis, we study and propose an evidential segmentation scheme of multi-echoes MR brain images based on Demspter-Shafer theory. Considering each neighbor as an information source, we propose the use of a weighted spatial combination rule. It allows to consider each voxel in its spatial environment and leads to a real region segmentation. Applied to multi-echoes MR data, our process provides accurate segmentation of the brain and allows the tumours detection. Moreover, we study the conflict issued from the spatial combination process. We show the conflict is a new source of evidence which reflects the spatial organization of the data. In particular, this data can be used by specialists to soften the previous segmentation results
Kocian, Sonntag Anne. "Evaluation de la qualité des images produites par des photons de haute énergie. Apport de la numérisation et application au contrôle des irradiations thérapeutiques". Toulouse 3, 1991. http://www.theses.fr/1991TOU30265.
Pełny tekst źródłajacquelin, christophe. "Segmentation de textures par algorithmes génétiques". Paris 5, 1996. http://www.theses.fr/1996PA05W072.
Pełny tekst źródłaBarré, Sébastien. "Modélisation, fusion et reconstruction 3D pour l'aide à la chirurgie maxillo-faciale". Poitiers, 2001. http://www.theses.fr/2001POIT2264.
Pełny tekst źródłaWali, Bacem. "Intéropérabilité sémantique entre les outils de traitement d'images en neuro-imagerie". Phd thesis, Université Rennes 1, 2013. http://tel.archives-ouvertes.fr/tel-00979471.
Pełny tekst źródłaTawileh, Mark Georges. "Développement d’une méthode optimale pour la synchronisation au mouvement respiratoire en médecine nucléaire". Electronic Thesis or Diss., Paris Est, 2009. http://www.theses.fr/2009PEST0078.
Pełny tekst źródłaTraditionally, nuclear medicine exams are carried out without taking respiratory motion into account. However, respiratory motion introduces blur into the images. We demonstrate that the amount of blur is positively related to the amplitude of respiratory motion and the spatial resolution of the imaging system. This becomes critical when the amplitude of respiratory movement becomes greater than the effective FWHM (full width half maximum) of the imaging system. In this situation, the global resolution of the system (integrating the effective resolution and the respiratory motion) is determined more by the amplitude of respiratory motion than by the effective FWHM of the imaging system. Recent technological advances in nuclear medicine have greatly improved the spatial resolution of SPECT and PET, allowing an FWHM up to 5 mm and 4 mm respectively. This is much lower than the amplitude of motion of the thoraco-abdominal organs which can be over 10 mm according to our meta-analysis. It is therefore necessary to account for respiratory motion in order to take full advantage of these improvements in spatial resolution. We have developed a video based motion tracking system of respiratory motion and a method based on processing of acquired dynamic images. We evaluated the performance of each and compared them with the performance of a pneumatic belt. We present the preliminary results of a comparison of these three methods during myocardial perfusion SPECT
BOŁDAK, Cezary. "Extraction et caractérisation 3D des réseaux vasculaires en imagerie scanner multibarette : application aux réseaux des membres inférieurs et des coronaires". Rennes 1, 2003. http://www.theses.fr/2004REN10092.
Pełny tekst źródłaRialle, Vincent. "Aide au diagnostic et à l'apprentissage dans un domaine médical incertain, incomplet et évolutif : étude des méthodes existantes et proposition d'une méthodologie nouvelle". Phd thesis, Grenoble 1, 1987. https://theses.hal.science/tel-00325679.
Pełny tekst źródłaRialle, Vincent. "Aide au diagnostic et à l'apprentissage dans un domaine médical incertain, incomplet et évolutif : étude des méthodes existantes et proposition d'une méthodologie nouvelle". Phd thesis, Université Joseph Fourier (Grenoble), 1987. http://tel.archives-ouvertes.fr/tel-00325679.
Pełny tekst źródłaAbrishami-Moghaddam, Hamid. "Segmentation d'images multidimensionnelles d'IRM cardiaque pour l'étude du comportement dynamique et la reconstruction 3D du cœur". Compiègne, 1998. http://www.theses.fr/1998COMP1107.
Pełny tekst źródłaHassainia, Farid. "Apport à l'imagerie anatomo-fonctionnelle du cerveau : méthodes d'interpolation sur la forme réelle de la tête & fusion d'images". Compiègne, 1992. http://www.theses.fr/1992COMPD471.
Pełny tekst źródłaOgier, Arnaud. "Méthodes de restauration en imagerie médicale tri-dimensionnelle". Rennes 1, 2005. http://www.theses.fr/2005REN1S100.
Pełny tekst źródłaRubeaux, Mathieu. "Approximation de l'Information Mutuelle basée sur le développement d'Edgeworth : application au recalage d'images médicales". Phd thesis, Université Rennes 1, 2011. http://tel.archives-ouvertes.fr/tel-00632128.
Pełny tekst źródłaAuvray, Vincent. "Estimation et segmentation des mouvements transparents dans des séquences d'images fluoroscopiques avec application au débruitage". Rennes 1, 2006. http://www.theses.fr/2006REN1S075.
Pełny tekst źródłaDupas, Alexandre. "Opérations et Algorithmes pour la Segmentation Topologique d'Images 3D". Phd thesis, Université de Poitiers, 2009. http://tel.archives-ouvertes.fr/tel-00466706.
Pełny tekst źródłaGalisot, Gaëtan. "Segmentation incrémentale et interactive d'images médicales 3D". Thesis, Tours, 2018. http://www.theses.fr/2018TOUR4035.
Pełny tekst źródłaThis research work describes a new interactive and incremental method for the segmentation of 3D medical images. The a priori information associated to the anatomical structure to analyze is leamed in a local way. Several local atlases, each one describing only one anatomical structure are constwcted from a training dataset. Spatial relationships are also leamed between those regions aiming to position the local atlases inside the whole image. During the segmentation process, the graph is used in an incremental way allowing fast and partial segmentation. fle user can also interact during the local atlas posiboning in order toimprove the segmentation quality. A voxel classification by a hidden Markov random field is employed toprovide the local segmentations. We also propose s post-processing step in order to correct the systematiceuors that a segmentation can achieve
Masson-Sibut, Agnès, i Agnès Masson-Sibut. "Développement d'un processus coopératif de traitement d'images ultrasonores pour le référencement géométrique de structures osseuses en chirurgie orthopédique". Phd thesis, Université Paris-Est, 2013. http://tel.archives-ouvertes.fr/tel-00906101.
Pełny tekst źródłaGuillemin, Hervé. "Amelioration de la resolution spatiale des images scintigraphiques de medecine nucleaire. Application a la glande thyroide". Cergy-Pontoise, 1997. http://www.theses.fr/1997CERG0036.
Pełny tekst źródłaChevrie, Jason. "Flexible needle steering using ultrasound visual servoing". Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1S098/document.
Pełny tekst źródłaThe robotic guidance of a needle has been the subject of a lot of research works these past years to provide an assistance to clinicians during medical needle insertion procedures. However, the accurate and robust control of a needle insertion robotic system remains a great challenge due to the complex interaction between a flexible needle and soft tissues as well as the difficulty to localize the needle in medical images. In this thesis we focus on the ultrasound-guided robotic control of the trajectory of a flexible needle with a beveled-tip. We propose a 3D model of the interaction between the needle and the tissues as well as a needle tracking method in a sequence of 3D ultrasound volumes that uses the artifacts appearing around the needle. Both are combined in order to obtain good performances for the tracking and the modeling of the needle even when motions of the tissues can be observed. We also develop a control framework based on visual servoing which can be adapted to the steering of several kinds of needle-shaped tools. This framework allows an accurate placement of the needle tip and the compensation of the physiological motions of the patient. Experimental results are provided and demonstrate the performances of the different methods that we propose
Flórez-Valencia, Leonardo. "Modèle d'état de cylindre généralisé et la quantification de sténoses artérielles en imagerie 3D". Lyon, INSA, 2006. http://theses.insa-lyon.fr/publication/2006ISAL0038/these.pdf.
Pełny tekst źródłaIn this thesis, we are interested in the use of a generalized cylinder state model for semi-automatic analysis of three-dimensional vascular images. This model is used on two levels: for image segmentation and quantification of the stenosis degree. The model is introduced in a vessel tracking strategy based on the Kalman state estimator, associated with the segmentation of plane contours by the level sets algorithm known as ``fast marching''. The interpretation of the model as a continuous geometrical object grants access to the analytical formulas used for stenosis quantification such as diameters and transversal areas. The algorithm was evaluated on a basis of 6 physical phantoms imaged in computed tomography angiography and in magnetic resonance angiography
Acosta-Tamayo, Oscar Dario. "De la navigation exploratoire virtuelle à la planification d'interventions endovasculaires". Rennes 1, 2004. https://tel.archives-ouvertes.fr/tel-00007555v2.
Pełny tekst źródłaLaguitton, Soizic. "Suivi spatio-temporel des artères coronaires en imagerie scanner multidétecteur". Rennes 1, 2008. http://www.theses.fr/2008REN1S003.
Pełny tekst źródłaThe application we are dealing with concerns the image guided endovascular surgery. Our aim is to assess the optimal catheter trajectory, by analysing the surroundings from the inside of the deformable structures in motion. The strategy is to track the coronary in 3D+T MSCT sequences. It researches the displacement of a point located on the vessel during a cardiac cycle. A coarse research is first performed and then refined. The point selection criterion uses Euclidean distance between local descriptors of the vessel. The accuracy and robustness of the developed methods are measured on sequences containing simulated linear and non linear movements. We applied the methods to extract trajectories of coronary segments during one cardiac cycle
Labiche, Alexandre. "Contribution à l’étude du stroma des carcinomes ovariens par une analyse morphologique, morphométrique et expérimentale, à l’échelle histologique et ultrastructurale : mise en évidence de l’importance de la vascularisation". Caen, 2008. http://www.theses.fr/2008CAEN4002.
Pełny tekst źródłaThe ovarian carcinoma is a cancer of very poor prognosis, as diagnosis occurs at an advanced stage. A better understanding of the natural history of this cancer is critical interest in order to discover new targeted therapies and to determine new markers for prognosis prediction and therapeutic follow-up. We have chosen to study the tumour stroma which plays probably a crucial role in the tumorigenesis and drug resistance of ovarian carcinomas. This study highlighted that the amount of blood vessels, mast cells and stroma can be used as prognosis indicators. Then, we have focused our study on peritoneal metastasis which are responsible of the recurrence of this disease. We have also finalized an in vivo mice model of peritoneal carcinosis to investigate the different steps of stroma development. Finally, we have tested on this model the effect of an anti-angiogenic drug associated or not with classical chemotherapy
Makki, Malek. "Vers une segmentation optimale d'images cardiaques acquises par RMN pour la reconstruction tridimensionnelle du coeur". Compiègne, 1997. http://www.theses.fr/1997COMP1059.
Pełny tekst źródłaMarque, Isabelle. "Segmentation d'images médicales tridimensionnelles basée sur une modélisation continue du volume". Phd thesis, Grenoble 1, 1990. http://tel.archives-ouvertes.fr/tel-00338755.
Pełny tekst źródłaGu, Jia. "Mise en correspondance spatio-temporelle par chaînes attribuées et splines plaques minces pour la reconstruction 3-D des coronaires en imagerie R-X". Rennes 1, 2005. http://www.theses.fr/2005REN1S189.
Pełny tekst źródłaWe have proposed a method to improve the 3-D reconstruction of the coronary in a sequence of bi-plane angiograms. This method allows reconstituting high level structural entities from a preliminary low level segmentation by means of a matching technique (such as ASM and TPS-based registration) and perceptual grouping rules (directional continuity, colinearity, proximity, shape similarity, …). A temporal matching aimed to take advantage of the heart-induced motion to remove ambiguities related to the superposition or crossing of the structures. The missing parts of the branches were then assessed through a feedback to the original image. The centerline and contour completion were undertaken using a minimal path technique between disconnected components. It made use of a dynamic programming algorithm associated with a likelihood measure that relied on both geometric and intensity features
Castro, Miguel. "Navigation endovasculaire augmentée : mise en correspondance d’images pré- et per-opératoires". Rennes 1, 2010. http://www.theses.fr/2010REN1S183.
Pełny tekst źródłaOur work lies within the scope of the endovascular navigation (catheterization, stenting,. . . ), where complex difficulties related to the anatomical structural deformation arise when they are subjected to the introduction of relatively rigid tools (rigid guides, stent). The contribution of this thesis deals with the optimal use of intraoperative data in order to establish correspondence of preoperative (3D CT) and intraoperative (2D angiography) data within an augmented reality system for angionavigation. The establishment of this correspondence is based on the decomposition of the 3D/2D transformation (projective transformation plus 3D/3D rigid transformation) and algorithms for estimating parameters (intrinsic, extrinsic) under the constraints of the interventional environment. This approach involves a process of calibration for the intrinsic parameters of the C-arm, a decomposition of the 3D/3D rigid transformation into two transformations whereof the two sets of extrinsic parameters are, for one, a registration method restricted to the plane of the operating table, and can be, for the other, given by the imaging device or obtained through a 3D optical tracking system. The readjustment of the 3D model describing the initial nondeformed preoperative patient data is considered through a geometric method estimating deformations due to tool / tissue interactions and based on intraoperative observations. Acquisitions on phantoms under clinical conditions and real data were used to evaluate the proposed approach
Bekaert, Virgile. "Développement d'un tomographe à émission monophotonique dédié au petit animal". Université Louis Pasteur (Strasbourg) (1971-2008), 2006. https://publication-theses.unistra.fr/public/theses_doctorat/2006/BEKAERT_Virgile_2006.pdf.
Pełny tekst źródłaCiofolo, Cybèle. "Segmentation de formes guidée par des modèles en neuro-imagerie : intégration de la commande floue dans une méthode de segmentation par ensembles de niveau". Rennes 1, 2005. http://www.theses.fr/2005REN1S150.
Pełny tekst źródłaFerré, Jean-Christophe. "Evaluation et optimisation de lʹacquisition et du post-traitement de lʹétude de la perfusion cérébrale par ʺ Arterial Spin Labeling ʺ". Rennes 1, 2011. http://www.theses.fr/2011REN1B149.
Pełny tekst źródłaArterial spin labeling (ASL) is a magnetic resonance perfusion imaging technique for measuring cerebral blood flow (CBF) which uses magnetically labeled arterial blood water as an endogenous tracer. ASL is completely noninvasive and can be repeated because it is performed without injection of contrast media, or radiation exposure. Moreover, CBF quantification is convenient and reproducible. However ASL is a low signal-to-noise ratio measurement technique. This technique becomes available on clinical MRI scanner. In this context, the aim of this work was to assess and optimize the image acquisition and the data processing acquired with two clinical techniques. We have demonstrated a correlation between acquisition parameters and hemodynamic parameters and we showed a maps’ quality improving using 32-channel coil combined with parallel imaging. New denoising methods were implemented and an optimized complete workflow was used to compare fASL and BOLD fMRI. A “template” approach was also assessed to detect individual increased perfusion area. Clinically, we used ASL to detect hypoperfusion defect on acute ischemic stroke and focal perfusion abnormalities in patients with chronic and resistant depression. Our results showed that a combination of optimized conditions acquisition and dedicated processing could help ASL to be more accurate in clinical research and practice
Chaudhry, Adnan Rashid. "Traitement d’image appliqué aux images d’autofluorescence dans le cadre de la Dégénérescence Maculaire Liée à l’Age (DMLA)". Paris, ENMP, 2009. http://www.theses.fr/2009ENMP1682.
Pełny tekst źródłaAge-related Macular Disease (AMD) is the leading cause of blindness in people over the age of 55. In its early stages, the patients may still have no visual impairment. In advanced stages, a wet and a dry form have to be distinguished. The wet form is defined by the growth of new vessels under the retina. The dry form is characterized by atrophies often called geographic atrophies of the photoreceptors and the Retinal Pigment Epithelium. In both forms the central retina may be destroyed by subsequent photoreceptor degeneration with severe vision loss. In recent years, Fundus AutoFluorescence (FAF) imaging has shown to be useful for AMD, especially for dry AMD type with regards to diagnosis, documentation of changes, identification of disease progression, and monitoring of novel therapies. The FAF images of the retina are obtained with an angiograph equipped with a scanning laser of 488 nm wavelength (Scanning Laser Ophthalmoscope (SLO)). The autofluorescence is emitted by the presence of a pigment (lipofuscin), which is a good indicator of the retinal activity. The FAF images are captured with a SLO in a sequence of 15-20 images, each having low signal to noise ratio and low contrast. The objective of the thesis is the development of tools for the automatic processing of FAF images. These tools will help the specialists in the diagnosis and follow up of the disease
Gorges, Sébastien. "Vers un système de navigation 3D en neuroradiologie interventionnelle". Phd thesis, Université Henri Poincaré - Nancy I, 2007. http://tel.archives-ouvertes.fr/tel-00165960.
Pełny tekst źródłageste thérapeutique. Cette machine permet l'acquisition d'une image 3D montrant les artères du patient (ou 3DXA). Cependant, le contrôle visuel du déploiement des
outils (guide, cathéter...) est effectué en 2D avec une image temps réel (ou fluoroscopie). Cette thèse a pour ambition de contribuer à l'amélioration des techniqu
es de guidage en proposant des outils permettant une utilisation de l?image 3D durant le traitement.
Les images étant acquises avec la même machine d'angiographie, nous avons consacré une partie de notre travail au développement de méthodes fiables de calibrage de
la chaîne image portée par l'arceau rotatif de la machine. Le but était de comprendre si l'arceau se déformait ou non sous l'influence de son poids.
Tirant parti du fait que les images sont acquises avec la même machine, nous avons ensuite proposé une méthode de recalage 3D2D entre l'image 3DXA et la fluorosc
opie. Cette méthode exploite les capteurs de position du système et incorpore les déformations subies par le système.
Suite à ces travaux, un système permettant la fusion de l'image 3DXA avec la fluoroscopie a été développé en collaboration avec GE Healthcare et évalué au CHU de Nanc
y pour le traitement des anévrismes cérébraux.
Enfin, un nouveau système doté de deux chaînes images (ou système bi-plan) a été installé à Nancy durant notre thèse. Après avoir développé une méthode de détection 2D du g
uide dans les images fluoroscopiques, nous avons initié une première étude de la reconstruction 3D du guide à partir des images bi-plan.
Bouraoui, Bessem. "Segmentation automatique de l’arbre coronarien à partir d’images angiographiques 3D+T de scanner". Strasbourg, 2009. http://www.theses.fr/2009STRA6171.
Pełny tekst źródłaThe objective of this thesis is to segment automatically the coronary arteries in images of scanner X. The images do not comprise only the heart, but also all the trunk of the body. A first stage consisted in removing any other structure than the heart in the image. An extraction of the aorta appeared necessary to us, then a localization of the germs of the coronary arteries will be carried out on the wall of this aorta. Once these germs are detected, an application of region growth is carried out, with a criterion of acceptance based on the Hit-ot-Miss transform. We based ourselves on a mathematical morphology operator, the Hit-ot-Miss transform. We combined his extension to the gray levels, with the blur alternative, which made our contribution to mathematical morphology. This work contributes to the evolution and the development of the vascular segmentation on two plans. In pratical terms of the contribution, three fully automatic algorithms were worked out, a first one to segment the heart, a second one to segment the aorta, and a third one for the segmentation of the coronary arteries. These algorithms have encouraging results, validated by an expert in cardiology, with 90% of correct results, the 10% remainders correspond to images of bad quality. In terms of methodology, this work allowed to integrate an new approach of segmentation, consisting in guiding the tools for image treatment by a priori knowledge, like her anatomical knowledge