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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Segmentation et recalage d'images TDM multi-phases de l'abdomen pour la planification chirurgicale / Segmentation and registration of CT multi-phase images for abdominal surgical planning

Zhu, Wenwu 13 April 2015 (has links)
La fusion d’images TDM de phase artérielles et veineuses est cruciale afin d’assurer une meilleure planification chirurgicale. Cependant, le recalage non-rigide d’images abdominales est encore un challenge à cause de la respiration qui fait glisser les viscères abdominaux le long de la paroi abdominale, créant ainsi un champ de déformation discontinu. L’objectif de cette thèse est de fournir un outil de recalage précis pour les images TDM multi-phases de l’abdomen.Comme la zone de glissement dans l’abdomen est difficile à segmenter, nous avons d’abord implémenté deux outils de segmentation interactifs permettant une délinéation en 10 minutes de la paroi abdominale et du diaphragme. Pour intégrer ces zones de glissement comme a priori, nous réalisons le recalage sur de nouvelles images dans lesquelles la paroi abdominale et les viscères thoraciques ont été enlevés. Les évaluations sur des données de patient ont montré que notre approche fournit une précision d’environ 1 mm. / The fusion of arterial and venous phase CT images of the entire abdominal viscera is critical for a better diagnosis, surgi-cal planning and treatment, since these two phase images contain complementary information. However, non-rigid regis-tration of abdominal images is still a big challenge due to the breathing motion, which causes sliding motion between the abdominal viscera and the abdo-thoracic wall. The purpose of this thesis is to provide an accurate registration method for abdominal viscera between venous and arterial phase CT images.In order to remove the sliding motion effect, we decide to separate the image into big motion and less motion regions, and perform the registration on new images where abdo-thoracic wall and thoracic viscera are removed. The segmentation of these sliding interfaces is completed with our fast interactive tools within 10 minitues. Two state-of-the-art non-rigid registration algorithms are then applied on these new images and compared to registration obtained with original images. The evaluation using four abdominal organs (liver, kidney, spleen) and several vessel bifurcations shows that our approach provides a much higher accuracy within 1 mm.

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