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No guidelines for the treatment of Kommerell diverticulum (KD) have been established. Endovascular treatment with arch vessel reconstruction of 4 patients with a right-sided aortic arch and aberrant left subclavian artery are presented herein. A 39-year-old woman and 47-year-old man experienced dyspnea and retrosternal pain. The first patient concomitantly underwent left subclavian transposition and thoracic endovascular aortic repair (TEVAR). The second patient underwent bilateral carotid-subclavian bypass grafting, followed by TEVAR and KD embolization. The 2 other patients were 72- and 75-year old men who presented with KD and type B dissection, in which these conditions were characterized by acute thoracic pain in the former patient and were noted on incidental body scan for prostatic adenocarcinoma in the latter. The third patient underwent carotid-subclavian bypass grafting, followed by TEVAR and subclavian plugs, and in the fourth patient, regular follow-up with antihypertensive therapy was scheduled. After a mean follow-up period of 12 months, all patients were alive.

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To assess the results of endovascular treatment in a large population of patients suffering from post-thrombotic syndrome (PTS) due to iliocaval occlusive disease.In this retrospective multi-center study, 698 patients treated by stenting for PTS in 15 French centers were analyzed. Primary, primary assisted, and secondary patency rates were assessed, and clinical efficacy was evaluated using Villalta and Chronic Venous Insufficiency Questionnaire in 20 questions (CIVIQ-20) scores. Outcomes were compared against pre-operative CT-based severity of the post-thrombotic lesions in the thigh (4 grades).Technical success, defined as successful recanalization and stent deployment restoring rapid anterograde flow in the targeted vessel, was obtained in 668 (95.7%) patients with a complication rate of 3.9%. After a mean follow-up of 21.0 months, primary patency, primary assisted patency, and secondary patency were achieved in 537 (80.4%), 566 (84.7%), and 616 (92.2%) of the 668 patients, respectively. Venous patency was strongly correlated to the grade of post-thrombotic changes in the thigh, with secondary patency rates of 96.0%, 92.9%, 88.4%, and 78.9%, respectively, for grades 0 to 3 (p = .0008). The mean improvements of Villalta and CIVIQ-20 scores were 7.0 ± 4.7 points (p .0001) and 19.1 ± 14.8 points (p .0001), respectively.Endovascular stenting as a treatment option for PTS due to chronic iliocaval venous occlusion generates a high technical success, low morbidity, high midterm patency rate, and clinical improvement. Venous patency was strongly correlated to the severity of post-thrombotic lesions in the thigh.

In recent years, transcatheter aortic valve implantation (TAVI) without predilation (direct TAVI) has become the preferred method for implanting TAVI prostheses. Appropriate patient selection is important to avoid suboptimal outcomes and associated complications.To evaluate whether aortic valve calcification measured with computed tomography predicts suboptimal results from direct TAVI with a self-expanding prosthesis.Single-centre retrospective analysis of patients who received a CoreValve™ prosthesis (Medtronic, Minneapolis, MN, USA) in a direct TAVI procedure between January 2018 and March 2019. Aortic valve calcification assessment (aortic valve calcium score, calcium volume and calcium mass) was calculated from the computed tomography scan before TAVI. Procedural characteristics, need for postdilation and complications were analysed.Of 168 included patients, 18 were postdilated. Aortic valve calcium score (4259 vs. 2578; P0.001), calcium volume (1184 vs. 647mmA high aortic valvular calcium score, assessed by computed tomography scan, is an independent predictor of suboptimal prosthesis implantation outcomes in direct TAVI.

The National Council on Radiation Protection (NCRP) report no. 168 recommended that during fluoroscopically guided interventions (FGIs), each patient should be monitored when one of the following thresholds is reached: an air kerma > 5 Gy, a kerma area product (KAP) > 500 Gy.cm2, a fluoroscopy time > 60 min, or a peak skin dose (PSD) > 3 Gy. Whereas PSD is the most accurate metric regarding the prevention of radiological risks, it remains the most difficult parameter to assess. We aimed to evaluate the relevance of the other, more accessible metrics and propose new optimized threshold (OT) for improved patient follow-up. Overall, 108 patients who underwent FGI in which at least one NCRP threshold was reached and PSD was measured were considered. The correlation between all metrics was assessed using principal component analysis (PCA). ROC curves and the sensitivity/specificity of both NCRP and OT to predict PSD > 3 Gy were evaluated. The PCA shows that FGI can be decomposed with two components based on time and dose variables. Only KAP and kerma were correlated with PSD. The overall sensitivity and specificity of the new OT regarding KAP (67.6/93.0), kerma (97.3/81.7), and time (62.2/62.0) were better compared with NCRP thresholds (97.3/16.9, 40.5/95.4, and 21.6/74.7). This study shows that fluoroscopy time is not a relevant metric when used to predict PSDs > 3 Gy. By adapting KAP and kerma thresholds to predict PSD over 3 Gy, patient follow-ups following vascular FGI can be improved. • In vascular fluoroscopically guided interventions, principal component analysis demonstrates that between fluoroscopy time, KAP, and kerma, only the two last were correlated to the peak skin dose. • Optimized thresholds replacing NRCP ones obtained with ROC curves analysis were 85,451 μGy.cm2, 2938 mGy, and 41 min for KAP, kerma, and fluoroscopy time respectively. • Improvements to trigger patient follow-up after vascular fluoroscopically guided interventions may be obtained by using the optimized thresholds.

Given the growing prevalence of obesity and metabolic syndrome, the management of hepatic steatosis, especially its quantification, is a major issue. We assessed the quantification of liver steatosis using four different MR methods, in order to determine the one that is best correlated with the reference method which consists of histological measurement by liver biopsy.Seventy-one successive patients requiring liver biopsy for acute or chronic liver disease were enrolled prospectively between March 2017 and March 2018, 11 were excluded and 60 were reported. Liver MR (1.5 T) was organised in order to be performed the same day, using four different steatosis quantification techniques (3-echo MRI, 6-echo MRI, 11-echo MRI and MR Spectroscopy). Quantitative histological and imaging data were compared. In a secondary analysis, we studied the possible influence of alcohol drinking, hepatic iron overload, and the presence of liver fibrosis.All four MR techniques were found to have excellent correlations with the histological measurements: 3-echo MRI (r = 0.852, p 0.001), 6-echo MRI (r = 0.819, p 0.001), 11-echo MRI (r = 0.818, p 0.001) and MR Spectroscopy (r = 0,812, p 0,001). Interestingly, we also found that the presence of alcohol consumption, iron overload and fibrosis did not interfere with measurements, whichever technique was used.In the evaluation of hepatic steatosis, our study showed very good correlations of all four MR techniques with the histological standard. There was no confounding factor in a representative group of patients with associated liver conditions such as alcohol consumption, fibrosis and iron overload, for each technique. All four MR techniques may be used in daily practice.

Background Proper segmentation of the liver from medical images is critical for computer-assisted diagnosis, therapy and surgical planning. Knowledge of its vascular structure allows division of the liver into eight functionally independent segments, each with its own vascular inflow, known as the Couinaud scheme. Couinaud's description is the most widely used classification, since it is well-suited for surgery and accurate for the localization of lesions. However, automatic segmentation of the liver and its vascular structure to construct the Couinaud scheme remains a challenging task. Methods We present a complete framework to obtain Couinaud's classification in three main steps; first, we propose a model-based liver segmentation, then a vascular segmentation based on a skeleton process, and finally, the construction of the eight independent liver segments. Our algorithms are automatic and allow 3D visualizations. Results We validate these algorithms on various databases with different imaging modalities (Magnetic Resonance Imaging (MRI) and Computed Tomography (CT)). Experimental results are presented on diseased livers, which pose complex challenges because both the overall organ shape and the vessels can be severely deformed. A mean DICE score of 0.915 is obtained for the liver segmentation, and an average accuracy of 0.98 for the vascular network. Finally, we present an evaluation of our method for performing the Couinaud segmentation thanks to medical reports with promising results. Conclusions We were able to automatically reconstruct 3-D volumes of the liver and its vessels on MRI and CT scans. Our goal is to develop an improved method to help radiologists with tumor localization.

To highlight the advantages of real time fluoroscopy guided electrode-array (EA) insertion (FGI) during cochlear implants surgery. All surgical procedures were performed in a dedicated operating room equipped with a robotic C-arm cone beam device, allowing for intraoperative real time 2D FGI and postoperative 3D imaging. Only straight EAs were used. Patients were sorted out in three groups: ANAT, with anatomical concerns; HP, with residual hearing; NPR: patients with no particular reason for FGI. In all cases the angle of EA-insertion was measured. In the HP group pre and postoperative hearing were compared. The radiation delivered to the patient was recorded. Fifty-three cochlear implantation procedures were achieved under fluoroscopy in 50 patients from November 2015 to January 2020 (HP group: n = 10; ANAT group: n = 13; NPR group: n = 27). In the ANAT group, FGI proved to be helpful in 8 cases (61.5%), successfully guiding the surgeon during EA -insertion. On average, the angle of insertion was at 424° ± 55°. In the HP group, a controlled smooth EA-insertion was carried out in all cases but one. The targeted 360° angle of insertion was always reached. Hearing preservation was possible with an eventual average drop of 30 ± 1.5 dB. In the NPR group, FGI helped control the quality of insertion in all cases and appeared very informative in five (17.8%): one EA-misrouting, three stuck EAs, and one case with hidden electrodes out of the cochlea in revision surgery. Final 3D cone beam CT scan double-checked the EA position in all adults. The radiation dose was equivalent to a bit less than four digital subtract radiographs. The FGI is a very useful adjunct in cochlear implantation in all cases of expected surgical pitfalls, in patients with residual hearing, and even in case without preoperative particular reason, with low irradiation.

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Introduction The last decade has seen a steady increase worldwide in the prevalence of end-stage renal disease (ESRD). Hemodialysis is the major modality of renal replacement therapy (RRT) in 70% to 90% of patients, who require well-functioning vascular access for this procedure. The recommended access for hemodialysis is an arteriovenous fistula or a vascular graft. However, recourse to central venous catheters remains essential for patients whose chronic renal disease is diagnosed at the end stage or in whom an arteriovenous fistula cannot be created or maintained. Tunneled dialysis catheter (TDC) exposure can induce venous stenosis and occlusions and can result in superior vena cava syndrome and/or vascular access loss. Exhaustion of conventional vascular accesses is 1 of the greatest challenges that nephrologists and patients have to face. Several unconventional salvage-therapy routes for TDC placement in patients with exhausted upper body venous access have been reported in the literature. Methods We report 2 new cases of intra-atrial TDC placement for patients with exhausted vascular access and perform a meta-analysis of cases from the literature. Results A total of 51 patients were included. The TDC was inserted by a cardiovascular surgeon in all cases. At the end of follow-up, 75% patients were alive. The median survival time was 25 months. Survival time of hemodialysis patients with intra-atrial TDC was lower than that observed with conventional TDC. Conclusions This unconventional technique is safe and functional for hemodialysis patients with exhausted venous access. Atrial vascular access for TDC placement is salvage therapy and is therefore potentially lifesaving.

Background Combined preoperative portal and hepatic vein embolization (biembolization, BE) has been recently described and may further enhance preoperative FLR growth. The objective of this study was to compare the efficacy of combined preoperative biembolization and portal vein embolization (PVE). Methods This study was performed between 2010 and 2017. From 2010 to 2014, patients only underwent preoperative PVE. After 2014, BE was proposed as an alternative to PVE. Liver volumetry was assessed by a CT-scan before BE or PVE and then three weeks later. Results During the study period, 72 patients underwent radiological procedures that included 41 PVE (PVE group) and 31 BE (BE group). The time elapsing between the procedure and surgery was similar (p = 0.760). The mean percentage of FLR ratio hypertrophy in the PVE group was 31.9% (±34), but reached 51.2% (±42) in the BE group (p = 0.018) and this difference remained significant under multivariate analysis that included age, gender, body mass index, diabetes mellitus, cirrhosis and NASH. The kinetic growth rates were 19% (±17%) and 8% (±13%) in the BE and PVE groups, respectively (p = 0.026). Conclusion This study shows that BE induces higher hypertrophy than portal vein embolization before major liver resection with no more morbidity.

Resume De nombreuses methodes ont ete decrites afin d’ameliorer l’hypertrophie du futur foie restant (FFR) avant hepatectomie majeure dans le but de prevenir une insuffisance hepatique postoperatoire. Les mecanismes d’hypertrophie hepatique sont a l’heure actuelle mal connus. Toutefois, l’hyper-debit arteriel cause par l’hypoxie hepatique, l’augmentation intravasculaire des forces de cisaillement (« Shear stress ») liee a l’hyperpression portale, et la synthese de nombreux mediateurs inflammatoires et de facteurs de croissance semblent jouer un role preponderant. A l’inverse, l’obstruction biliaire, la denutrition, la consommation excessive d’alcool, le diabete, le sexe masculin, l’âge et l’infection virale semblent alterer la regeneration hepatique. L’ensemble de ces facteurs inhibant ou favorisant l’hypertrophie hepatique peut s’associer a des degres divers et ainsi expliquer les grandes variations d’hypertrophie observees en fonction des patients et des procedures. Parmi ces procedures, l’embolisation radiologique de la veine porte (EP) droite etendue ou non aux branches du segment 4, l’embolisation de la veine hepatique droite sequentielle ou plus recemment l’EP combinee a l’embolisation de la veine hepatique (biembolisation) sont les plus souvent realisees. Les procedures chirurgicales incluent la ligature portale droite, la bipartition hepatique partielle ou totale associee a la ligature portale pour hepatectomie en deux temps (ALPPS) et plus recemment l’embolisation de la veine porte combinee a la ligature arterielle (APEAL). Cette revue tente de clarifier la physiologie de la regeneration hepatique rapportee aux differentes procedures radiologiques et chirurgicales, afin d’en analyser les avantages et les inconvenients, et surtout les resultats attendus en termes d’hypertrophie.

Developing methods to segment the liver in medical images, study and analyze it remains a significant challenge. The shape of the liver can vary considerably from one patient to another, and adjacent organs are visualized in medical images with similar intensities, making the boundaries of the liver ambiguous. Consequently, automatic or semi-automatic segmentation of liver is a difficult task. Moreover, scanning systems and magnetic resonance imaging have different settings and parameters. Thus the images obtained differ from one machine to another. In this article, we propose an automatic model-based segmentation that allows building a faithful 3-D representation of the liver, with a mean Dice value equal to 90.3% on CT and MRI datasets. We compare our algorithm with a semi-automatic method and with other approaches according to the state of the art. Our method works with different data sources, we use a large quantity of CT and MRI images from machines in various hospitals and multiple DICOM images available from public challenges. Finally, for evaluation of liver segmentation approaches in state of the art, robustness is not adequacy addressed with a precise definition. Another originality of this article is the introduction of a novel measure of robustness, which takes into account the liver variability at different scales.

Various procedures can promote hypertrophy of the future liver remnant (FLR) before major hepatectomy to prevent postoperative liver failure. The pathophysiological situation following portal vein embolization (PVE), hepatic artery ligation/embolization or hepatectomy remains unclear. On one hand, the main mechanisms of hepatic regeneration appear to be driven by hepatic hypoxia (involving the hepatic arterial buffer response), an increased portal blood flow inducing shear stress and the involvement of several mediators (inflammatory cytokines, vasoregulators, growth factors, eicosanoids and several hormones). On the other hand, several factors are associated with impaired liver regeneration, such as biliary obstruction, malnutrition, diabetes mellitus, male gender, age, ethanol and viral infection. All these mechanisms may explain the varying degrees of hypertrophy observed following a surgical or radiological procedure promoting hypertrophy the FLR. Radiological procedures include left and right portal vein embolization (extended or not to segment 4), sequential PVE and hepatic vein embolization (HVE), and more recently combined PVE and HVE. Surgical procedures include associated liver partition and portal vein ligation for staged hepatectomy, and more recently the combined portal embolization and arterial ligation procedure. This review aimed to clarify the pathophysiology of liver regeneration; it also describes radiological or surgical procedures employed to improve liver regeneration in terms of volumetric changes, the feasibility of the second step and the benefits and drawbacks of each procedure.

Liver cancer is the third deadliest cancer in the world. It characterizes a malignant tumor that develops through liver cells. The hepatocellular carcinoma (HCC) is one of these tumors. Hepatic primary cancer is the leading cause of cancer deaths. This article deals with the diagnostic process of liver cancers. In order to analyze a large mass of medical data, ontologies are effective; they are efficient to improve medical image analysis used to detect different tumors and other liver lesions. We are interested in the HCC. Hence, the main purpose of this paper is to offer a new ontology-based approach modeling HCC tumors by focusing on two major aspects: the first focuses on tumor detection in medical imaging, and the second focuses on its staging by applying different classification systems. We implemented our approach in Java using Jena API. Also, we developed a prototype OntHCC by the use of semantic aspects and reasoning rules to validate our work. To show the efficiency of our work, we tested the proposed approach on real datasets. The obtained results have showed a reliable system with high accuracies of recall (76%), precision (85%), and F-measure (80%).

This paper presents a novel framework devoted to the detection of HCC (Hepato-Cellular Carcinoma) within hepatic DCE-MRI (Dynamic Contrast-Enhanced MRI) sequences, by a deep learning approach. In clinical routine, radiologists usually consider different phases during contrast injection (before injection; arterial phase; portal phase for instance) for HCC diagnosis. By employing a U-Net architecture, we are able to identify such tumors with a very high accuracy (98.5% of classification rate at best) for a small cohort of patients, which should be confirmed in future works by considering larger groups. We also show in this paper the influence of patch size for this machine learning process, and the positive impact of employing all phases available in DCE-MRI sequences, compared to use only one.

Resume Le pronostic des atteintes arterielles traumatiques, consequences de polytraumatismes, de traumatismes penetrants ou iatrogenes, depend du risque ischemique d’aval et d’un eventuel syndrome hemorragique, justifiant un bilan exhaustif et une prise en charge rapides. Le diagnostic repose en premier lieu sur l’examen clinique, dont la normalite n’exclut pas formellement des lesions vasculaires : au moindre doute un complement par echo doppler ou tomodensitometrie (TDM) est necessaire. Si l’arteriographie demeure le gold standard, ses indications sont aujourd’hui plus electives, signifiant la possibilite de meconnaitre des lesions qui se manifesteront avec retard : c’est dire alors l’importance du suivi. Dans le cadre d’une etroite collaboration multidisciplinaire, l’arteriographie peut constituer le premier temps d’une embolisation d’hemostase ou de la restauration de continuite par stent ou stent-graft. Ces techniques endovasculaires sont moins delabrantes que la chirurgie ouverte, notamment pour les regions difficilement accessibles, comme les territoires sous-clavier ou axillaire ou le risque d’atteinte du plexus brachial est egalement reduit. Au niveau des membres inferieurs, les lesions focales femorales et ischemiques sous-poplitees se pretent tout particulierement a la radiologie interventionnelle.

Background We report two unusual separate complications after uterine artery embolization for a late postpartum haemorrhage. This report appeared important to us in view of the apparent absence of any other publications on this topic. Case presentation We report the case of a 25-year-old woman, gravida 3, para 1, admitted for uterine bleeding 7 days after a spontaneous delivery at term, in our university hospital. A suction curettage and then, after persistent bleeding, uterine artery embolization were necessary. Immediately after the embolization, a bilateral ovarian thrombosis occurred, subsequently followed by amenorrhea, due to uterine synechiae, and depression. Hysteroscopic surgery was performed to remove the adhesions. A complete work-up for thrombophilia showed a heterozygous mutation of the factor V gene R506Q. The pathology examination found subinvolution of the placental bed. One month after treatment of the synechiae (and insertion of a copper IUD for contraception), the woman's menstrual cycle returned to normal. Her clinical examination 19 months later was normal. Conclusions This case teaches us that one rare complication can hide another! It is important to consider the diagnosis of subinvolution of the placental bed in cases of late PPH and to know the complications associated with vascular artery embolization in order to provide the most rapid and least invasive treatment., Highlights • Arterial embolization is associated with ovarian thrombosis. • Do not forget the subinvolution of the placental bed in late postpartum haemorrhage. • Suction curettage can lead to uterine synechiae.

This study analysed CT patterns of the acute dissected aortic arch using original biometric features along with comparison with normal aortas.The diagnostic CT scans of 57 patients (42 males, age (mean ± SD: 64.5 ± 13.8 years) admitted with acute Stanford type A dissection involving the aortic arch were analysed by semi-automatic detection protocol of the true lumen of the dissection. We measured the distances from the apex to the ascending and descending aorta, the curvilinear length of the entire arch and of its segments (especially between the brachiocephalic artery trunk and the left subclavian artery), as well as the surface area, angle, height and shift of the arch. These measurements were compared with results previously obtained in a healthy cohort in an analysis adjusted for age, sex and weight. The surface area and rotation of the false lumen were also analysed.Compared to normal aortic arches (N), dissected aortic arches (D) were longer (D: 155 ± 26 mm, N: 135 ± 25 mm, p = 0.002), higher (D: 51 ± 10 mm, N: 45 ± 9 mm, p = 0.04), and with a more anterior apex (shift: D: 1.19 ± 0.56, N: 1.40 ± 0.62, p = 0.007). False lumen occupied between 47-65% of the aorta, turned preferentially clockwise and its rotation decreased progressively along the arch.The morphology of the dissected aortic arch differs from that of the normal arch. Thus, our compilation of aortic arch measurements may help improve existing endovascular devices and/or design of new endoprostheses. Advances in knowledge: In this article, we provide a comprehensive set of measurements of the dissected aortic arch, and show that dissected aortic arches are longer, higher, and with a more anterior apex than normal arches.

This paper deals with the personalized simulation of blood flow within the liver parenchyma, by considering a complete pipeline of medical image segmentation, organ volume reconstruction, and numerical simulation of blood diffusion. To do so, we employ model-based segmentation algorithms developed with ITK/VTK librairies, CATIA software for volumetric reconstructions based on NURBS and Abaqus solution for adapted simulation of Darcy’s law. After presenting experimental results of each step, we explore scientific and technical bottlenecks so that a valid digital hepatic blood flow phantom may be developed in our future research, in direct relation with current open challenges in this domain.

Background and Objectives: Interventional endoscopic ultrasound (EUS) is a promising novel approach for intravascular interventions. The aim of this study was to assess the feasibility and safety of a EUS-guided intrahepatic portosystemic shunt (EGIPS) with portal pressure gradient measurement in a live porcine model. Methods: The left hepatic vein (LHV) or the inferior vena cava (IVC) was punctured with a needle that advanced into the portal vein (PV). A guidewire was then inserted into the PV, and a needle knife was used to create an intrahepatic fistula between LHV and PV. Portal pressure was recorded. The fistula was dilated with a balloon and a biliary metal stent was deployed between LHV and PV under sonographic and fluoroscopic observation. A portocavography validated the patency of the stent. Necropsies were realized after euthanasia. Results: Portosystemic stenting was achieved in 19/21 pigs. Final portocavography confirmed stent patency between PV and LHV or IVC in 17 pigs (efficacy of 81%): Four stents were dysfunctional as two were thrombosed and two were poor positioned. Portal pressure was documented before and after shunting in 20/21 pigs. Necropsies revealed that 19/21 procedures were transesophageal and two were transgastric. Hemoperitoneum and pneumothorax were found in one pig and hemothorax was found in two pigs. Morbidity was 14.2% (3/21 animals). Conclusion: EGIPS was feasible in 91% of cases, functional in 81%, with 14.2% per procedure morbidity. EGIPS still needs to be assessed in portal hypertension pig models with longer follow-up before being considered as an alternative when the transjugular intrahepatic portosystemic shunt fails.

Nowadays transcatheter aortic valve implantation (TAVI) is an accepted alternative to surgical aortic valve replacement for high-risk patients (pts). Successful TAVI procedures for failed aortic surgical bioprosthesis (TAV-in-SAV) have already been reported. In the presented two cases of TAV-in-SAV implantation a strut distortion of the stent was revealed on angiographic imaging and confirmed on control CT scan. In both procedures, a dislocation of the medtronic core valve (MCV) prosthesis during implantation led to valve retrieval, with a necessity of reloading it in the 18F introducer before subsequent implantation of the same valve in correct position.

Resume Propos Le lymphome est une pathologie polymorphe qui n’epargne pas les arteres. On distingue les atteintes perivasculaires et intravasculaires dont les pronostics et traitements sont differents. Patients et methodes Nous presentons ici un cas d’atteinte perivasculaire et un cas d’atteinte intravasculaire, puis nous discutons les particularites semiologiques propres a chaque type d’atteinte. Resultats Le premier cas est une femme qui a presente une atteinte arterielle pseudo-anevrismale perivasculaire iliaque externe puis une dilatation des cavites pyelocalicielles, dans le cadre d’un lymphome non hodgkinien ; le deuxieme cas est un homme ayant presente un lymphome intravasculaire realisant un anevrisme d’une artere femorale superficielle puis d’une artere iliaque primitive. Conclusion La distinction entre atteinte arterielle perivasculaire et intravasculaire repose sur un large faisceau d’arguments et est primordiale pour une prise en charge optimale des patients atteints de lymphome.

La directive 97/43/EURATOM du 30 juin 1997 pointe la radiologie interventionnelle comme une des pratiques speciales (Article 9) susceptibles de delivrer des doses elevees, et pour lesquelles il est demande de veiller a ce que les equipements, les procedures, les programmes d’assurance qualite et la formation des operateurs soient particulierement appropriees. En effet, l’utilisation d’un rayonnement X de faible energie lors de procedures allant de quelques secondes a plusieurs heures pour les examens complexes, renvoie inevitablement a des risques stochastiques et deterministes. L’evaluation de la dose maximum a la peau est donc une donnee appreciable dans l’objectif d’un suivi dermatologique du patient. Dans cette etude nous avons choisi d’utiliser comme detecteur les films radiochromiques XR-RV3-Gafchromic ® afin d’obtenir une cartographie de la dose a la peau recue par le patient lors d’une procedure. Les films radiochromiques sont interessants car ils permettent a la fois de visualiser et de quantifier la region de dose maximale. Nous presentons ici les etapes preliminaires a une utilisation sur patient des films, a savoir l’etude des caracteristiques physiques, l’etalonnage en dose, la lecture par scanner plat et l’exploitation des films avec le logiciel de traitement d’images ImageJ. Les resultats obtenus montrent que l’utilisation des films radiochromiques est pertinente pour une evaluation dosimetrique sur patient. Plus particulierement, la reponse des films differe de moins de 3,6 % entre l’etalonnage a 80 kV et 120 kV et l’incertitude globale reste inferieure a 20 % jusqu’a une dose de 12 Gy. L’evolution de la reponse du film dans le temps etant negligeable, la lecture peut etre faite immediatement et l’exploitation du film necessite moins de 15 minutes pour obtenir la cartographie de la dose. L’application de cette technique de mesure in-vivo pour 58 procedures a permis de mettre en evidence une dose maximale a la peau superieure a 3 Gy pour 12 patients. Ces patients ont alors ete orientes vers un suivi dermatologique. Parmi ces patients, l’evaluation de la dose peau a partir des indicateurs dosimetriques fournis par l’installation aurait mene au suivi de seulement 4 patients.

Endoleaks have been referred to as the “Achilles heel” of endovascular aortic aneurysm repair (EVAR) and are the most common complication of this procedure. An endoleak can maintain a high systemic blood pressure within the aneurysm sac, potentially leading to rupture. Follow-up is therefore mandatory to detect and classify possible endoleaks. Computed tomography (CT) remains the gold standard for follow-up, but provides no hemodynamic information on endoleaks and has the disadvantages of exposing patients to iodine contrast and X-ray radiation. Exposure to radiation could be reduced in various ways, by simplifying the triphasic protocol using dual-energy CT imaging, limiting the amount of radiation per slice using iterative reconstruction, and reducing the follow-up schedule that could be altered to include non-ionizing radiation imaging techniques. Contrast-enhanced ultrasound (CEUS) is an interesting alternative to CT, as is magnetic resonance (MR) imaging that can be used as an alternative or for complementary imaging. Long-term follow-up schedules are currently based on repeated CT. However, more recently alternative follow-up protocols have been proposed for patients with no endoleaks nor increase in aneurysmal sac size. These new protocols consist of CT imaging at 1month and 1year after treatment, subsequently followed by CEUS. Nevertheless, the mechanical structure of the stent-graft must still be verified by CT. The use of patient-specific risk-adjusted follow-up protocols, based on preoperative imaging and the first postoperative results, is gradually becoming more and more widespread.

Endovascular repair of abdominal aortic aneurysms with a stent graft is limited by the persistence or recurrence of endoleaks. These are believed to be related to the recanalization of the aneurismal sac by endothelialized neochannels, which could lead to late type I and II endoleaks. Embolization has been proposed to treat or prevent endoleaks, but presently commercialized embolizing materials have several drawbacks and do not fully prevent endoleak recurrence. A novel chitosan hydrogel that is injectable, radiopaque and contains sodium tetradecyl sulfate (STS), a well-known sclerosing agent, was developed in order to combine blood flow occlusion and endothelium ablation properties. chitosan/STS hydrogels were characterized and optimized using rheometry, scanning electron microscopy, swelling and ex vivo embolization assay. They were shown to exhibit rapid gelation and good mechanical properties, as well as sclerosing properties. Their potential for the embolization of aneurysms was subjected to preliminary in vivo evaluation in a bilateral iliac aneurysm model (three dogs) reproducing persistent endoleaks after endovascular aneurysm repair (EVAR). At 3 months no endoleak was detected in any of the three aneurysms treated with chitosan/STS hydrogels. In contrast, type I endoleaks were detected in two of the three aneurysms treated with chitosan hydrogels. Generally, chitosan/STS hydrogels have great potential as embolizing and sclerosing agents for EVAR and possibly other endovascular therapies.

Background Renal artery aneurysms (RAA) are a relatively rare vascular entity. Treatment could be either surgical or via an endovascular route. The main aim of therapy is to prevent lethal rupture. Purpose To evaluate the angiographic and clinical results after endovascular treatment (EVT) of eight renal artery aneurysms. Material and Methods From January 2000 to June 2011, 18 patients presented with 18 renal artery aneurysms. One was classified as Rundback type I, 15 were type II, and two aneurysms were type III. Endovascular treatment was considered unsafe in 10 cases (all were Rundback type II), and were referred to surgery. The remaining eight aneurysms were treated endovascularly during altogether nine sessions. Among these, four patients were asymptomatic, three were hypertensive, and one presented with ipsilateral flank pains. Aneurysmal sac diameter varied between 12 and 50 mm. EVT included selective coil embolization in five cases, covered stents in two cases, and parent artery occlusion in one. Results Follow-up with CT angiography was obtained in all endovascularly treated aneurysms (range 6–54 months, mean 15 months). Complete durable occlusion was achieved in all aneurysms except one, which showed re-expansion after 20 months and was retreated with covered stent implantation. Clinically silent, branch occlusion occurred after four procedures with subsequent limited (less than 25%) ischemic parenchymal loss. All patients were discharged with preserved renal function. Clinical improvement was noted in all symptomatic patients. Conclusion Endovascular treatment of renal artery aneurysms is an adequate treatment and can be proposed, if feasible, as first step.

Background Isolated non-traumatic renal artery dissection (RAD) is a rare disorder with uncertain natural history. The management may be surgical reconstruction, endovascular repair, or conservative medical treatment, yet no official consensus had been established. Purpose To report the management of four cases of isolated non-traumatic RAD, emphasizing the beneficial role of conservative medical treatment. Material and Methods From the year 2000 till 2011, four male patients with mean age of 42.5 years (range 34–48 years) presented with isolated non-traumatic RAD and were initially treated with medical therapy. Transcatheter in situ thrombolysis was performed in a case with thrombotic occlusion. Results Isolated non-traumatic RAD in four patients involving at least seven branches progressed to thrombotic occlusion in two branches, luminal narrowing in five, dual lumens in two, and aneurysmal dilatation in three. Medical treatment was efficacious in three patients, who showed persistent preserved renal function, controlled blood pressure, and favorable arterial remodeling. After failure of medical therapy, the fourth patient was referred to surgery. Thrombolysis was successful to dissolute an occluding thrombotic dissection. Conclusion Conservative therapy is safe and effective when the renal artery is patent and blood pressure is controlled: we propose it as the first line of treatment, reserving interventional management for refractory cases.

In this paper, we propose to segment liver tumor within ROI (Regions Of Interest) of MR (Magnetic Resonance) images by combining the smoothed shock noise reduction filter, that we introduced in a previous work, and a fuzzy approach. Besides the whole pipeline dedicated to our application, the originality of our method is to combine fuzzy information (membership degree to clusters) and geometrical features (Zernike moments) in the final defuzzification step. Thanks to a dataset representative of the variability of tumors' geometries and pixel intensities, we demonstrate that our approach is accurate, in every cases of liver lesions of our benchmark. We also show that the combination of both our two tools (denoising filtering and fuzzy segmentation) is the reason of the efficiency of this methodology.

Objectif : determiner l’interet des gants radio-attenuateurs plombes pour diminuer l’exposition des mains des operateurs, en radiologie interventionnelle et au bloc operatoire. Materiel et methode : on a utilise des gants radio-attenuateurs plombes du marche, des dosimetres TLD thermoluminescents, un fantome anthropomorphe de calibration en osteodensitometrie, une main anthropomorphe. Les mesures etaient realisees sur 2 installations : l’une avec capteurs plans, l’autre avec amplificateur de brillance. On a compare les doses recues par dosimetres sans et dans un gant, dans le champ direct (10 series de mesures dont 2 avec amplificateur de brillance) et dans le diffuse (3 series sur capteurs plans), en scopie et graphie. Resultats : dans le diffuse, les dosimetres dans le gant mesuraient une diminution de dose, variant de 1 a 3. Dans le champ direct, 7 mesures sur 10 montraient une augmentation de dose dans le gant (13 a 42 %). 3/10 mesures montraient une quasi stabilite de dose avec le gant (–3,3 % a +2 %). Conclusion : nos mesures objectivent une efficacite des gants radio-attenuateurs plombes dans le diffuse. Dans le rayonnement direct, le port des gants radio-attenuateurs plombes entraine une augmentation de la dose – main, du fait des reglages automatiques des parametres.

Points essentiels Le developpement des techniques et du materiel permet aujourd’hui la prise en charge therapeutique endovasculaire des syndromes aortiques aigus touchant l’aorte descendante. Les anevrismes rompus, les dissections aortiques, mais egalement les hematomes aortiques intra-muraux et les ulceres penetrants pourront beneficier de la mise en place d’endoprothese couverte aortique. L’urgence de la prise en charge varie selon la nature de la lesion aortique initiale et de sa tolerance clinique. Les stents non couverts et la fenestration aortique sont utilises dans les syndromes de malperfusion viscerale dans le cadre des dissections aortiques, en fonction du mecanisme de l’ischemie.

Objectifs Connaitre les risques evolutifs des pathologies aortiques traites medicalement et leur traitement. Savoir standardiser la repetition et la realisation des examens aortiques mais egalement leur interpretation, avec notamment des mesures aortiques reproductibles. Savoir reconnaitre les images caracterisant l’evolution de la pathologie aortique traitee medicalement : repermeabilisation d’un hematome parietal, d’un faux chenal thrombose, dilatation d’un faux chenal permeable. Messages a retenir Hematome parietal, ulcere penetrant, dissection de type B qui peuvent se manifester initialement bruyamment, peuvent ne requerir qu’un traitement medical. Ils doivent beneficier d’un suivi regulier par TDM ou IRM car il s’agit de lesions evolutives qui peuvent se compliquer a bas bruit. Il est necessaire de standardiser le calendrier, la realisation des examens et leur interpretation afin d’assurer un suivi de l’evolutivite reproductible. Resume La surveillance des syndromes aortiques aigus traites medicalement repose sur l’imagerie en coupe, TDM ou IRM. Elle est indispensable quelle que soit la technique, l’evolutivite se faisant souvent a bas bruit ; elle repose sur une confrontation standardisee avec les examens precedents. Les dissections aortiques traitees medicalement necessitent un suivi regulier et reproductible (12 a 18 mois) a la recherche d’une dilatation anevrismale du faux chenal, d’une malperfusion viscerale, d’une extension ou une evolution. La surveillance d’un hematome parietal, d’un ulcere beneficieront egalement d’un suivi rapproche a la recherche d’une evolutivite ou d’une repermeabilisation.