Contents
Academic literature on the topic 'Artères coronaires – Tomographie'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Artères coronaires – Tomographie.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Dissertations / Theses on the topic "Artères coronaires – Tomographie"
Xie, Lizhe. "Reconstruction 3-D des artères coronaires en imagerie rotationnelle R-X." Rennes 1, 2012. http://www.theses.fr/2012REN1S143.
Full textThis work addresses the 3-D reconstruction of coronary arteries from a limited number of projections in rotational angiography. We propose two approaches to solve the ill-posed inverse problem. The first one is formulated as a statistical reconstruction problem and uses a Maximum a Priori (MAP) algorithm, in which L0, L1 and L2 regularizations are evaluated. The second one applies an object-oriented reconstruction, introducing a morphological model of the structure to be reconstructed. It is formed by the coronary artery centerlines and contours. The inverse problem resolution leads to minimize the strain energy of the model in both space and time. Finally the initial assumption of a prior segmentation of the structures leads to a sparse reconstruction problem that allows the parameter number in the system and the search for the solution to be restricted within a subdomain of f. The accuracy and limitations of each algorithm are evaluated and compared using a dynamic heart phantom. This dynamic sequence has been built from patient data acquired on a MSCT scan. A C-arm rotational R-X coronary angiography was then simulated using the Siemens Axiom System imaging protocol to build a sequence of 80 grey level projections
Blondel, Christophe. "Modélisation 3D et 3D+t des artères coronaires à partir de séquences rotationnelles de projections rayons X." Phd thesis, Nice, 2004. http://tel.archives-ouvertes.fr/tel-00346997/en/.
Full textValet, Nathalie. "Aide au diagnostic cardiovasculaire par superposition en 2 et 3D des images de coronarographie et tomoscintigraphie : segmentation de l'arbre coronaire et représentation 3D." Vandoeuvre-les-Nancy, INPL, 2004. http://www.theses.fr/2004INPL042N.
Full textThis work contributes to the conception of a diagnosis aid tool for coronary diseases. Currently, this diagnosis is done with two exams (coronarography, tomoscintigraphy) providing two complementary information: the arteries anatomy and the myocardium perfusion. The aim is creating a new multi-modal image showing clearly the link between both information (stenosis and ischemia) by registrating and superimposing data both in 2D and 3D. The first part deals with the automatic segmentation of arteries on coronarography in order to distingllish vessels of each side. Then, the related perfusion data is superimposed in 2D. The second part proposes an algorithm free from any acquisition systems dimensions as we use registration results. Using homologous points, arteries are 3D-reconstructed and the patient schematic tree is superimposed on his perfusion volume. This way, the link between stenosis and perfusion is clearly shown. Tests have been done on a phantom and nine patients
Menguy, Pierre-Yves. "Suivi longitudinal des endoprothèses coronaires par analyse de séquences d'images de tomographie par cohérence optique." Thesis, Clermont-Ferrand 1, 2016. http://www.theses.fr/2016CLF1MM30/document.
Full textThis thesis deals with the segmentation and characterization of coronary arteries and stents in Optical Coherence Tomography (OCT) imaging. OCT is a very high resolution imaging that can appreciate fine structures such as the intimal layer of the vascular wall and stitches (struts). The objective of this thesis is to propose software tools allowing the automatic analysis of an examination with a runtime compatible with an intraoperative use. This work follows Dubuisson's thesis in OCT, which proposed a first formalism for light segmentation and strut detection for metal stents. We revisited the treatment chain for these two problems and proposed a preliminary method for detecting bioabsorbable polymer stents. Surface modeling of the stent made it possible to estimate a series of clinical indices from the diameters, surfaces and volumes measured on each section or on the entire examination. Applying the stent to the wall is also measured and visualized in 3D with an intuitive color scale. The arterial lumen is delineated using a Fast Marching short path search algorithm. Its originality is to exploit the image in the native helical form of the acquisition. For the detection of the metallic stent, the local maxima of the image followed by a shadow zone have been detected and characterized by a vector of attributes calculated in their neighborhood (relative value of the maximum, slope in gray level, symmetry ...). Peaks corresponding to struts were discriminated from the surrounding speckle by a logistic regression step with learning from a field truth constructed by an expert. A probability of belonging to the peaks to struts is constructed from the combination of attributes obtained. The originality of the method lies in the fusion of the probabilities of the close elements before applying a decision criterion also determined from the ground truth. The method was evaluated on a database of 14 complete examinations, both at the level of pixels and struts detected. We have also extensively validated a method of non-rigid registration of OCT images using bitters matched by an expert on the source and target exams. The objective of this registration is to be able to compare cut-to-cut examinations and indices calculated at the same positions at different acquisition times. The reliability of the strain model was evaluated on a corpus of forty-four pairs of OCT exams from a Leave-One-Out cross validation technique
Chauvet, Cindy. "Fusion TEMP-TDM en imagerie cardiaque : vers une sectorisation spécifique de la perfusion myocardique." Thesis, Clermont-Ferrand 1, 2011. http://www.theses.fr/2011CLF1MM10.
Full textNo abstract available
Bousse, Alexandre. "Problèmes inverses, application à la reconstruction compensée en mouvement en angiographie rotationnelle X." Phd thesis, Université Rennes 1, 2008. http://tel.archives-ouvertes.fr/tel-00361396.
Full textUne fois le mouvement estimé, la reconstruction tomographique à un instant de référence est effectuée par une optimisation aux moindres-carrés qui inclut le mouvement ainsi qu'un terme de pénalité qui favorise les valeurs d'intensités fortes pour les voxels au voisinage de la ligne centrale 3-D, et les faibles valeurs pour les autres. Cette méthode a été testée sur des données simulées basées sur des lignes centrales 3-D préalablement extraites de données MSCT.
Le, roy Julien. "Optimisation des explorations tomodensitométriques des artères coronaires chez l’enfant atteint de cardiopathie congénitale." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTT058.
Full textCoronary computed tomography angiography (CCTA) has been increasingly used in pediatrics for diagnosis, follow-up, and pre or post-surgery assessment of coronary artery anomalies, and more generally in congenital heart diseases. However, its use remains limited by cardiac motion artifacts, potentially resulting in non-diagnostic acquisitions, and by children’s exposure associated with a risk of radiation induced cancers.The aim of this thesis was to evaluate and optimize CCTA performed in children with congenital heart disease.Fifty children (<18 years old), with congenital heart disease requiring coronary artery imaging were prospectively enrolled in the COROPEDIA clinical trial, specifically designed during the thesis (Observational study for feasibility and performance of sub-millisievert coronary computed tomography angiography for coronary artery anomalies in paediatric patients). Between 2017 and 2018, these children underwent a coronary CT angiography, performed on a wide-coverage, single-source CT. The first part of this work was dedicated to elaborating an optimized acquisition protocol, derived from adult studies (very few studies have been conducted with pediatric patients). Fifteen acquisition schemes were designed to deliver irradiation at the best theoretical moment, as a function of patient’s heart rate and variability. These selective multiphasic acquisitions fully answered the clinical question for every child, delivering a radiation dose equivalent to less than 4 months of natural background irradiation.Two additional studies were conducted to improve cardiac structure visualization while reducing further children’s exposure.The impact of motion correction algorithms in children undergoing CCTA was investigated. The results suggested that multiple phases provided significantly better interpretability than traditional single-phase acquisitions. However, the second motion correction algorithm generation offered similar interpretability in a single retrospectively processed cardiac phase and could be adopted to improve coronary artery visualization while reducing beam-on-time and children’s exposure to radiation.Finally, motion artifacts of every fifty patients were quantified in seven different cardiac phases. On a total of 5733 cardiac structures evaluated, optimal positions (70%, 80%, 40%, 47%, 50%, 54% of the R-R interval, respectively) and durations (10%, 20%, 50%, 50%, 20%, 10% of the cardiac cycle, respectively) of the acquisition window were defined as a function of children’s heart rates (≤60 bpm, 61-75 bpm, 76-85 bpm ; 86-100 bpm ; 101-130 bpm ; >130 bpm).These optimization strategies might be simultaneously implemented to achieve CCTA of diagnostic quality in any children, for less than 0.5 mSv, or two month of natural background irradiation
BLONDEL, Christophe. "Modélisation 3D et 3D+t des artères coronaires à partir de séquences rotationnelles de projections rayons X." Phd thesis, Université de Nice Sophia-Antipolis, 2004. http://tel.archives-ouvertes.fr/tel-00006067.
Full textNous proposons d'exploiter un nouveau mode d'acquisition angiographique, le mode rotationnel, pour produire des modélisations tridimensionnelles et dynamiques de l'arbre coronaire. Ces modélisations permettraient de s'affranchir des défauts intrinsèques aux images.
Notre travail se compose de trois étapes. Dans un premier temps, une reconstruction 3D multi-oculaire donne un modèle statique des lignes centrales des artères coronaires, prenant en compte le mouvement respiratoire. Par la suite, un mouvement 4D des artères coronaires est determiné sur l'ensemble du cycle cardiaque. Enfin, la connaissance des mouvements respiratoire et cardiaque permet de réaliser la reconstruction tomographique des artères coronaires.
Nous avons testé notre approche sur une base de 22 patients et avons proposé de nouveaux outils et applications cliniques à partir de ces modélisations tridimensionnelles et dynamiques. Ces outils diagnostiques ont été prototypés et feront l'objet d'une validation clinique.
Jaquet, Clara. "Vers la simulation de perfusion du myocarde à partir d'image tomographique scanner." Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1117/document.
Full textRecent advances in medical image computing have allowed automatedsystems to closely assist physicians in patient therapy. Computationaland personalized patient models benefit diagnosis, prognosisand treatment planning, with a decreased risk for the patient,as well as potentially lower cost. HeartFlow Inc. is a successfull exampleof a company providing such a service in the cardiovascularcontext. Based on patient-specific vascular model extracted from XrayCT images, they identify functionally significant disease in largecoronary arteries. Their combined anatomical and functional analysisis nonetheless limited by the image resolution. At the downstreamscale, a functional exam called Myocardium Perfusion Imaging (MPI)highlights myocardium regions with blood flow deficit. However,MPI does not functionally relate perfusion to the upstream coronarydisease.The goal of our project is to build the functional bridge betweencoronary and myocardium, by extrapolating the functional analysisfrom large coronary toward the capillary bed. This objective requiresextension from the coronary model down to the microvasculaturecombined with a functional analysis leading to the myocardium compartment.We expand a tree generation method subjected to functional principles,named Constrained Constructive Optimization, to generate multiplecompeting vascular trees. The algorithm simulates angiogenesisunder vascular volume minimization with flow-related and geometricalconstraints, adapting the simultaneous tree growths to patientpriors. This method provides a hybrid image-based and synthetic geometricmodel, starting from segmented epicardium coronary downto synthetic arterioles, filling the left ventricle myocardium.We then build a multiscale functional analysis pipeline to allowblood flow simulation from the coronaries to the myocardium. Thisis achieved with a 1D coronary model compatible with the hybridvasculature, and a spatial blood flow distribution analysis of the terminalsegments. The latter is performed using a similar nomenclatureto MPI, to enable patient-specific comparison with functional groundtruthdata.We connected the vascular anatomy to blood flow distribution inthe myocardium on several patient datasets. This multiscale frameworkpoints out several leads to refine the vascular network generationand fluid simulation methods. This patient-specific anatomicaland functional extrapolation is a first gateway toward myocardiumperfusion from X-ray CT data. Building such personalized computational model of patient could potentially help investigating cardiovascularcomplex physio-pathology, and, finally, improve the patientcare