Solid-pseudopapillary tumor of the pancreas: MR imaging findings in 21 patients.

PURPOSE: Solid-pseudopapillary tumor (SPT) of the pancreas is a rare, low-grade malignancy, which mostly occurs in adolescent and young adult females. The goal of this study was to retrospectively analyze the magnetic resonance (MR) imaging presentation of SPT of the pancreas. METHODS: We retrospectively reviewed the preoperative MR imaging examinations and the medical, surgical and histopathological records of 21 patients who underwent surgery for SPT of the pancreas. MR imaging included T1-weighted, T2-weighted, and gadolinium chelate-enhanced MR imaging. In addition, 10 patients had diffusion-weighted (DW) MR imaging. MR examinations were retrospectively reviewed for location, size, morphological features and signal intensity of the tumors. RESULTS: Nineteen women and 2 men (median age, 23 years; range, 14-59) were included. Seven patients (7/21; 33%) presented with abdominal symptoms. The median largest tumor diameter was 53mm (range, 32-141 mm). SPTs were located in the pancreatic head, body, and tail in 9 (9/21; 43%), 5 (5/21; 24%) and 7 (7/21, 33%) patients, respectively. All patients (21/21; 100%) had a single SPT. SPTs were more frequently oval (12/21; 57%), predominantly solid (12/21; 57%), fully encapsulated (16/21; 76%), larger than 30 mm (21/21; 100%), hypointense on T1-weighted MR images (21/21, 100%), hyperintense on T2-weighted MR images (21/21; 100%) and with an enhancing capsule after gadolinium-chelate administration (21/21; 100%). CONCLUSIONS: There is trend of appearance for SPT of the pancreas on MR imaging but that variations may be observed in a number of cases. SPT uniformly presents as a single, well-demarcated and encapsulated pancreatic mass

Revised diagnosis and severity criteria for sinusoidal obstruction syndrome/veno-occlusive disease in adult patients : a new classification from the European Society for Blood and Marrow Transplantation

Sinusoidal obstruction syndrome, also known as veno-occlusive disease (SOS/VOD), is a potentially life threatening complication that can develop after hematopoietic cell transplantation. Although SOS/VOD progressively resolves within a few weeks in most patients, the most severe forms result in multi-organ dysfunction and are associated with a high mortality rate (480%). Therefore, careful attention must be paid to allow an early detection of SOS/VOD, particularly as drugs have now proven to be effective and licensed for its treatment. Unfortunately, current criteria lack sensitivity and specificity, making early identification and severity assessment of SOS/VOD difficult. The aim of this work is to propose a new definition for diagnosis, and a severity-grading system for SOS/VOD in adult patients, on behalf of the European Society for Blood and Marrow Transplantation.Peer reviewe

How impedance measurements and imaging can be used to characterize the conductivity of tissues during the workflow of an electroporation-based therapy

International audienceIn this paper we investigate the possibility of using needles, which the interventional radiologist inserts near a deep-seated tumor during an electroporation-based therapy, to characterize the electrical conductivity of patient's tissues. Specifically, we propose to exploit voltage/current measurements and imaging that are performed prior to the application of electroporation pulses. The approach is partly based on the concepts of electrical impedance tomography; however, imaging is used to build a specific geometric model and compensate for the lack of information resulting from the small number of electrodes available. 3D canonical and clinical examples, where a few electrodes surround a tumor, demonstrate the feasibility of this method: solving the inverse problem to estimate tissues conductivity converges in a few iterations. For a given error on the measurement, it is also possible to calculate the error on the estimated conductivities. The uncertainty error with clinical data is at best 5% for one of the tissues identified, due to the limitations of the clinical device used. Various improvements to clinical devices are discussed to make the conductivity estimation more accurate but also to extract more information

Pratiques de la chimioembolisation artérielle hépatique du CHC en France en 2015

CERVOXY CLIN/Unité d'origineNational audienc

L’ischémie reperfusion induit une raréfaction du réseau microvasculaire rénal en lien avec une détérioration de la fonction rénale : étude dans un modèle préclinique porcin de transplantation rénale

International audienceObjectifsLe réseau microvasculaire est une cible majeure de l’ischémie reperfusion. Le but de cette étude était de caractériser le remodelage vasculaire du cortex rénal après ischémie reperfusion et de déterminer la partie la plus affectée.MéthodesNous avons utilisé un modèle préclinique porcin d’auto-transplantation rénale avec néphrectomie controlatérale dans lequel le greffon a été conservé 24 h à 4 °C dans la solution de conservation : University of Wisconsin. Trois mois après auto-transplantation, les reins porcins (n = 5) ont été étudiés ex vivo par micro-tomographie en les comparant à des reins natifs (n = 5 ; Fig. 1a). La morphologie du réseau vasculaire et notamment la densité et la tortuosité des segments vasculaires ont été analysés à partir d’un procédé d’analyse tridimensionnelle. Le débit sanguin cortical a également été évalué, ainsi que la fonction rénale et les lésions tissulaires.RésultatsL’ischémie-reperfusion rénale a conduit à une diminution du volume des segments vasculaires associée à une raréfaction des petits vaisseaux de moins de 30 μm, en particulier dans le cortex profond (Fig. 1b). Cette raréfaction microvasculaire a été corrélée à une détérioration de la fonction rénale accompagnée de protéinurie et de dysfonction tubulaire (Fig. 1c). Le débit sanguin cortical des greffons était diminué à 1 h et à 3mois après la transplantation. Dans le cortex total des greffons, il a été mis en évidence une augmentation du nombre de bifurcations des segments vasculaires et le développement d’un tissu fibreux qui participe au remodelage vasculaire (Fig. 1d).ConclusionCe travail apporte des indications sur le spectre lésionnel de l’ischémie reperfusion rénale et permettra de développer des futures thérapies dans le but d’améliorer la préservation du réseau microvasculaire du greffon rénal

Liver fibrosis staging with contrast-enhanced ultrasonography: prospective multicenter study compared with METAVIR scoring

International audienceWe prospectively assessed contrast-enhanced sonography for evaluating the degree of liver fibrosis as diagnosed via biopsy in 99 patients. The transit time of microbubbles between the portal and hepatic veins was calculated from the difference between the arrival time of the microbubbles in each vein. Liver biopsy was obtained for each patient within 6 months of the contrast-enhanced sonography. Histological fibrosis was categorized into two classes: (1) no or moderate fibrosis (F0, F1, and F2 according to the METAVIR staging) or (2) severe fibrosis (F3 and F4). At a cutoff of 13 s for the transit time, the diagnosis of severe fibrosis was made with a specificity of 78.57%, a sensitivity of 78.95%, a positive predictive value of 78.33%, a negative predictive value of 83.33%, and a performance accuracy of 78.79%. Therefore, contrast-enhanced ultrasound can help with differentiation between moderate and severe fibrosis.</p