Deformation Analysis to Detect and Quantify Active Lesions in 3D Medical Image Sequences

Evaluating precisely the temporal variations of tumor volumes is very important for at least three types of practical applications: pharmaceutical trials, decision making for drug treatment or surgery and patients follow-up. In this paper, we present a volumetric analysis technique, combining precise rigid registration of 3D medical images, non-rigid deformation computation and flow field analysis. Our analysis technique has two outcomes: the detection of evolving lesions and the quantitative measurement of volume variations. The originality of our approach is that no precise} segmentation of the lesion is needed but the approximative designation of a region of interest, which can be automatized. We distinguish between tissue transformation (image intensity changes without deformation) and expansion or contraction effects reflecting a change of mass within the tissue; a real lesion being generally the combination of both effects. The method is tested with synthesized 3D image sequences and applied, in a first attempt to quantify in-vivo a mass effect, to the analysis of a real patient case with Multiple Sclerosis

Calcul de variations de volume de lésions dans des images médicales tridimensionnelles

L'évaluation précise de la variation temporelle du volume d'une lésion est très importante pour diverses applications : recherche pharmaceutique et médicale, suivi des patients, prise de décision thérapeutique. Dans cet article, nous décrivons un modèle de croissance de lésions, qui nous sert à valider une technique originale de mesure de variation de volume. Dans un premier temps nous effectuons un recalage rigide des images, ensuite nous calculons le champ des déformations résiduelles que nous intégrons sur des surfaces emboîtées épousant la forme de la structure évolutive. Le maximum du profil obtenu correspond à la variation de volume cherchée dans le cas synthétique et conduit à des valeurs cohérentes avec l'intuition dans le cas d'un patient atteint de sclérose en plaques

Deformation Analysis to Detect and Quantify Active Lesions in Three-Dimensional Medical Image Sequences

International audienceAbstract--Evaluating precisely the temporal variations of lesion volumes is very important for at least three types of practical applications: pharmaceutical trials, decision making for drug treatment or surgery, and patient follow-up. In this paper we present a volumetric analysis technique, combining precise rigid registration of three-dimensional (3-D) (volumetric) medical images, nonrigid deformation computation, and flow-field analysis. Our analysis technique has two outcomes: the detection of evolving lesions and the quantitative measurement of volume variations. The originality of our approach is that no precise segmentation of the lesion is needed but the approximative designation of a region of interest (ROI) which can be automated. We distinguish between tissue transformation (image intensity changes without deformation) and expansion or contraction effects reflecting a change of mass within the tissue. A real lesion is generally the combination of both effects. The method is tested with synthesized volumetric image sequences and applied, in a first attempt to quantify in vivo a mass effect, to the analysis of a real patient case with multiple sclerosis (MS)

Algorithmes flous : Application à la quantification du tissu adipeux en IRM abdominale

Le syndrome métabolique, associé à l'obésité est une pathologie en forte progression dans nos sociétés occidentales. Un marqueur jouant un rôle prépondérant dans le diagnostic de cette pathologie est le tour de taille, dépendant de la graisse viscérale et sous-cutanée. Nous proposons dans cet article une méthode automatique et fiable de segmentation des graisses viscérale et sous-cutanée utilisant succéssivement un algorithme de classification floue suivi d'un algorithme de connectivité nous permettant de nous affranchir des problèmes d'inhomogénéités du tissu adipeux et du champs magnétique

L'Hydroptère: A story of a dream

In 2009, l’Hydroptère broke the symbolic barrier of 50 knots and became the world fastest sailing boat over both 500 meters and 1 nautical mile. This major achievement relied on the high skills of the sailing team but also on technical advances of the boat, resulting from long years of studies and development. This achievement is also an open window to a new goal: flying around the world. In the present article, we present this long and incredible story, highlighting the different steps, the technology involved, and the background of that project.

Calcul de variation de volume de lésions dans des images médicales tridimensionnelles

National audienceno abstrac

Measuring Lesion Growth from 3D Medical Images

International audienceno abstrac