25 research outputs found
In vitro rat colonic wall imaging with MR endoluminal coil: feasibility study and histologic correlations
International audienc
Cryotherapy percutaneous for renal tumors: Our center's beginning experience
International audienceOBJECTIVE: To evaluate oncologic and functional outcomes after percutaneous cryoablation (PCA) for renal masses based on our single center experience. PATIENTS AND METHODS: We retrospectively identified 26 patients who underwent PCA for 28 tumors between November 2006 and June 2011. Patient's demographics and baseline clinical characteristics, tumor features, perioperative information, and postoperative outcomes we rerecorded. A biopsy was performed systematically before each procedure. Control imaging was obtained at 1, 3, 6 and 12 months, and yearly thereafter. Oncological outcomes were determined by radiographic evidence of tumor recurrence, which was defined by contrast enhancement at the cryoablation site on control imaging at M3. RESULTS: Patients had mean age of 70.1 years, mean Charlson comorbidity index (CCI) and body mass index) were 6 and 29 kg/m(2) respectively. There were 11 kidney transplants, including 4 solitary. Mean tumor size was 29.5mm and was represented mainly by clear cell renal cell carcinomas (16/28), endophytic (17/28) and midkidney (14/28) (+/-9.8). Twenty-five cryoablations were performed percutaneously by two lumbotomy. Mean clearance preoperative MDRD was 66,1 mL/min. Mean length of stay was 3.3 days (+/-2.2). Intraoperative complications consisted of 2 pneumothorax and 6 minor complications postoperative (Clavie
Quantification des graisses abdominales sous-cutanées et viscérales par résonance magnétique nucléaire du proton à 3T : application à un protocole de surnutrition
International audienc
Quantitative 3T MR imaging techniques for staging liver fat steatosis and fibrosis in chronic liver diseases: the HEPATOMAP protocol
International audienc
Measurement Tensors in Diffusion MRI: Generalizing the Concept of Diffusion Encoding
In traditional diffusion MRI, short pulsed field gradients (PFG) are used for the diffusion encoding. The standard Stejskal-Tanner sequence uses one single pair of such gradients, known as single-PFG (sPFG). In this work we describe how trajectories in q-space can be used for diffusion encoding. We discuss how such encoding enables the extension of the well-known scalar b-value to a tensor-valued entity we call the diffusion measurement tensor. The new measurements contain information about higher order diffusion propagator covariances not present in sPFG. As an example analysis, we use this new information to estimate a Gaussian distribution over diffusion tensors in each voxel, described by its mean (a diffusion tensor) and its covariance (a 4th order tensor)
Etude de modèles paramétriques pour l'estimation de la composition lipidique en spectroscopie de résonance magnétique : comparaison théorique des fonctions modèles et application in vivo
International audienc
Etude de modèles paramétriques pour l'estimation de la composition lipidique en spectroscopie de résonance magnétique : comparaison théorique des fonctions modèles et application in vivo
International audienc