Preoperative portal vein embolization with a combination of trisacryl microspheres, gelfoam and coils.

PURPOSE: To evaluate the safety and efficiency of preoperative portal vein embolization (PVE) with a combination of trisacryl microspheres, gelfoam and coils for inducing lobar hypertrophy in hepatobiliary malignancy patients. MATERIALS AND METHODS: PVE was performed by a percutaneous left approach in 63 patients with hepatic malignancy (hepatocarcinoma=38, colorectal metastasis=14, cholangiocarcinoma=11). The indication of PVE and surgery was evaluated by hepatic tumor board take into consideration to the tumor extension and the hepatic volume on initial and post-embolization CT-scans. The total functional liver volume (TELV) and future liver remnant (FLR) volume were measured before and 24±5days after PVE to assess FLR, TELV and FLR/TELV ratios. Efficiency evaluation was based on FLR increase, the ability to perform the hepatectomy and the hepatic function after surgery. Safety evaluation was determined by clinical and biological follow-up after embolization and surgery. RESULTS: PVE was successful in all the patients. The mean FLR volume increases by 57±56% after embolization (449±180cm(3) to 663±254cm(3)) (P<0.0001). The FLR/TELV ratio increases by 11% after PVE (25±8% to 36±12%). Three minors' complications were registered without impact on surgery, and four patients developed portal hypertension. Forty-nine patients underwent hepatectomy; none of them developed liver failure. Surgery was not performed in 14 patients due to tumor progression (n=9), inadequate hypertrophy of FLR (n=1) and portal hypertension (n=4). CONCLUSION: Preoperative PVE with a combination of trisacryl microspheres, gelfoam and coils is a safe and effective method for inducing contralateral hypertrophy before right hepatectomy in patients with advanced hepatobiliary malignancy.

Hepatocellular carcinoma vascularization: from the most common to the lesser known arteries.

Hepatocellular carcinoma is the sixth most common cancer throughout the world. It is almost exclusively arterially vascularized, unlike the vascularization of the liver, which has a dual supply with a portal component of 75 to 80% and an arterial component of 20 to 25%. The reference treatment for intermediary stages of the Barcelona (B) classification is hepatic artery chemoembolization. The aim of chemoembolization is to inject the tumor chemotherapy into the artery and then to embolize the artery (or arteries), which supply the tumor. For this, knowledge of the anatomy of the hepatic artery is essential. Approximately 55% of the patients belong to the modal distribution, although numerous anatomical variants exist and must be recognized. In addition, primarily non-hepatic arteries may contribute to the vascularization of some hepatocellular carcinomas. Furthermore, new arterial supplies can be recruited by tumors after surgical or chemoembolization treatments. The aim of this article is to describe the different arteries, which may vascularize hepatocellular carcinomas. These arteries must be looked for, recognized, and reported by the radiologist on cross-section examinations in the pre-treatment assessment.

Diagnosis and radiological treatment of digestive haemorrhage following supramesocolic surgery.

Digestive haemorrhage following supramesocolic abdominal surgery (cephalic duodenopancreatectomy, cholecystectomy, total oesogastrectomy) is a rare but serious complication, which can be life-threatening. Improvement in scanning techniques has made it possible to modify the diagnostic strategy and improve the therapeutic management of the patients. The aim of this iconographic review is to recall the causes of digestive haemorrhage following supramesocolic surgery and to illustrate the dominant role of tomodensitometry in diagnosing it and in planning and controlling the efficacy of endovascular treatment.

[Focal liver lesions in oncology]. / Lésions hépatiques en cancérologie générale.

In order to improve management of oncologic patients, a standardized 5-step approach should be considered: detection, characterization, locoregional and systemic staging, and post treatment follow up. The use of imaging techniques will be adapted to the clinical question at hand during multi-disciplinary review of cases. The role of the radiologist is to review the indications for each imaging modality and incorporate the results in the clinical context.

Diagnostic performance of MRI for detection of intestinal fistulas in patients with complicated inflammatory bowel conditions.

The diagnostic performance of magnetic resonance imaging (MRI) for detection of intestinal fistulas, other than perianal, in patients with known complicated inflammatory bowel conditions (CIBC) was investigated. Our study group consisted of 20 patients (12 women, mean age 43 years) with CIBC, including Crohn's disease (n=13), colonic diverticulitis (n=3), colitis after radiotherapy (n=3) and of postoperative origin (n=1). Eleven surgically proven enteral fistulas were known in ten (50%) of these patients, being of enterovesical (n=3), enterocolic (n=2), enteroenteral (n=2), rectovaginal (n=2), rectovaginovesical (n=1) and of entercutaneous (n=1) localisation. The other ten patients (50%), used as the control group, showed MR features of CIBC, although without any fistulous tract. Multiplanar T1- and T2-weighted sequences had been performed, including gadolinium-enhanced acquisition with fat saturation (1.5 T). MR findings were independently blindly and retrospectively reviewed by three radiologists for the presence and etiology of any fistula, as well as visualization and characterization of the fistulous tract. Results were compared with surgical findings (n=16) and clinical evolution (n=4). Interobserver agreement was calculated. Interobserver agreement kappa for fistula detection was 0.71. Overall sensitivity, specificity and accuracy for fistula detection were 78.6%, 75% and 77.2%, respectively. Sensitivity for fistula characterization was 80.6%, with visualization of the fistulous tract in all cases, whereby T1-weighted gadolinium-enhanced fat-saturated images were considered the most useful sequences. Gadolinium-enhanced MRI is a reliable and reproducible tool for detection of enteral fistulas secondary to inflammatory conditions.

[What is the thickness of the normal appendix on MDCT?]. / Quelle est l'épaisseur de l'appendice normal au scanner multibarrette?

OBJECTIVE: To determine the wall thickness and external diameter values of the normal appendix on multidetector computed tomography (MDCT). Materials and methods. A senior radiologist with no knowledge of the patient's surgical history prospectively examined the abdominal-pelvic CT scans of 57 consecutive adult patients with no suspicion for appendicitis. Most of the patients (50/57) received an intravenous iodinated contrast material injection, but none had gastrointestinal studies. All slices (1 and 5 mm) and multiplanar reconstructions were analyzed on a treatment console. The external diameter of the appendix, the thickness of the two appendicular walls, and the presence or absence of intraluminal gas were noted. RESULTS: The appendix was visualized in 82% of the cases (47/57). The mean external diameter was 6.7 mm+/-1.2 (range, 5.0-11.0 mm). The mean thickness of the two walls was 4.8 mm+/-1.0 (range, 2.6-6.4 mm). Intraluminal air was visualized in 87% of cases (41/47). CONCLUSION: Contrary to external diameter, the normal thickness of the appendix's two walls does not go beyond the threshold of 6 mm and therefore seems to be a reliable measurement for identifying a normal appendix using MDCT.

[Gastroduodenal perforation: the role of MDCT]. / Le scanner multi détecteurs améliore la détection des perforations d'ulcères gastro duodénaux.

OBJECTIVE: To determine whether multidetector computed tomography (MDCT) is helpful for early detection of gastroduodenal perforation. MATERIAL AND METHODS: Fifteen consecutive gastroduodenal perforations for ulcer were recorded in the HIS of a single institution. Reports were analyzed and classified according to the following signs: Was a pneumoperitoneum detected? Was there mention of a perforation site, and how was it depicted (axial or reformatted slices, thin or thick slices)? What were the other described features, including peritoneal fluid, abdominal fat blurring, and bowel wall thickening? RESULTS: All patients had a gastroduodenal perforation. MDCT identified pneumoperitoneum in 15 of 15 cases as compared with three of nine cases for plain films. The perforation site was seen in eight of 15: it was identified as a defect in the parietal wall (gastroduodenal). Six of eight cases were depicted in axial view. Two of them were only seen on MPR, coronal or sagittal view. CONCLUSION: MDCT improves the detection rate of pneumoperitoneum and provides critical data for locating the perforation using direct and indirect signs. Multiplanar images seem to improve radiologists' confidence.

[Is appendicolith a reliable sign for acute appendicitis at MDCT?]. / Le stercolithe est-il un signe fiable d'appendicite?

PURPOSE: To determine the frequency of detection of appendicoliths on normal appendix at multidetector row computed tomography (MDCT) with multiplanar reconstructions (MPR). MATERIALS AND METHODS: A senior radiologist, blinded to patient's surgical history, prospectively and independently reviewed abdominopelvic MDCT scans in 57 consecutive adult patients without symptoms suggesting appendicitis. Most patients had IV iodine injection, but no oral contrast. Thick (5 mm) and thin (1 mm) slices were analyzed on a workstation. MPR were available. Localization of the appendix, overall diameter, intraluminal gas and appendicolith were recorded. RESULTS: The appendix was visualized in 47/57 (82%). An appendicolith was found in 13%. Intraluminal gas was identified in 87%. The localization was retrocaecal (47%), mediocaecal (21%) or pelvic (32%). The mean overall diameter of the normal appendix was 6.7 mm +/- 1.2 (SD). CONCLUSION: Appendicolith was found in a significant number of normal patients at MDCT and don't represent a specific sign for appendicitis.

Evaluation of tumoral enhancement by superparamagnetic iron oxide particles: comparative studies with ferumoxtran and anionic iron oxide nanoparticles.

This study was designed to compare tumor enhancement by superparamagnetic iron oxide particles, using anionic iron oxide nanoparticles (AP) and ferumoxtran. In vitro, relaxometry and media with increasing complexity were used to assess the changes in r2 relaxivity due to cellular internalization. In vivo, 26 mice with subcutaneously implanted tumors were imaged for 24 h after injection of particles to describe kinetics of enhancement using T1 spin echo, T2 spin echo, and T2 fast spin echo sequences. In vitro, the r2 relaxivity decreased over time (0-4 h) when AP were uptaken by cells. The loss of r2 relaxivity was less pronounced with long (Hahn Echo) than short (Carr-Purcell-Meiboom-Gill) echo time sequences. In vivo, our results with ferumoxtran showed an early T2 peak (1 h), suggesting intravascular particles and a second peak in T1 (12 h), suggesting intrainterstitial accumulation of particles. With AP, the late peak (24 h) suggested an intracellular accumulation of particles. In vitro, anionic iron oxide nanoparticles are suitable for cellular labeling due to a high cellular uptake. Conversely, in vivo, ferumoxtran is suitable for passive targeting of tumors due to a favorable biodistribution.

Percutaneous radiofrequency ablation of hepatic tumors during temporary venous occlusion.

OBJECTIVE: We evaluated the feasibility, tolerance, and efficacy of percutaneous hepatic vein or segmental portal branch balloon occlusion during radiofrequency ablation of hepatic malignancies. SUBJECTS AND METHODS: Ten tumors were treated by percutaneous radiofrequency ablation during balloon occlusion of a hepatic vein (n = 8) or a segmental portal branch (n = 2). Venous occlusion was undertaken because the tumor was in contact with a hepatic vein (n = 3) or a portal branch (n = 1); because the tumor exceeded 35 mm in width (mean, 44 mm), which was considered the maximum size amenable to ablation in a single session (n = 2); or because of both large size and contact with a hepatic vein (n = 3) or a portal branch (n = 1). RESULTS: Vascular occlusion was always technically possible. Radiofrequency was delivered to one to three locations (mean, 1.9 locations) with a cluster electrode. The largest axis of radiofrequency-induced lesions after ablation with the cluster needle-between 42 and 51 mm (mean, 49 mm)-was always larger than the targeted tumor. These sizes were statistically larger than in a matched control group of patients who underwent radiofrequency ablation without vascular occlusion (p < 0.0003). After a mean follow-up of 12.6 months, CT and MR imaging revealed complete destruction of nine tumors after a single radiofrequency ablation treatment; one tumor required three treatments to achieve ablation. Five patients are tumor-free 12-18 months (mean, 14.4 months) after the first radiofrequency ablation treatment, and five developed new liver metastases. CONCLUSION: Temporary hepatic vein or portal branch occlusion during radiofrequency ablation can safely facilitate the treatment of large tumors or tumors in contact with the walls of large vessels.

[Smooth muscle mesentery associated with Epstein-Barr virus (EBV). Report of a case in a child with a liver transplant under FK506 regimen]. / Tumeur musculaire lisse mésentérique associée au virus d'Epstein-Barr (EBV). A propos d'un cas chez un enfant transplanté hépatique sous FK 506.

Smooth-muscle tumors, benign and malignant, are increasingly recognized in children who are immunocompromised because of HIV infection and organ transplantation. We report a case of an EBV-associated smooth-muscle tumor, of unusual location arising in a seven-year-old post-transplant patient who was previously treated for a lymphoproliferative disease. Five years after liver transplantation, a mesenteric tumor was diagnosed. The tumor was composed of spindle cells with smooth-muscle features. Immunohistochemical analysis was positive for muscle-specific actin and desmin, negative for EBV latent membrane protein (LMP-1). In situ hybridization revealed nuclear EBV sequences. This case underlines the role of EBV infection in the development of unusual smooth-muscle tumors after organ transplantation. The evolution of these rare tumors is uncertain.

[Large cell variant of small cell carcinoma of the ovary with hypercalcemia]. / Variante à grandes cellules d'un carcinome à petites cellules de l'ovaire avec hypercalcémie.

We describe an original distinct type of ovarian small cell carcinoma: large cell variant. The distinctive histologic features of tumor cells were the presence of large nuclei with prominent nucleoli and abundant eosinophilic cytoplasm. Immunohistochemistry revealed strong diffuse vimentin, smooth muscle actin positivity and slight reactivity with epithelial markers. Electron microscopy showed aggregates of intermediate filaments, intercellular attachments and no dense core granules. This tumor is associated with paraendocrine hypercalcemia in two thirds of cases. Parathyroid hormone-related protein was focally positive. This tumor is characterized as a very lethal neoplasm, occurring primarily in young women.