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Resume La lymphographie par resonance magnetique se sert de sequences tres ponderees en T2 pour obtenir une representation anatomique des structures contenant des liquides stationnaires ou presentant une vitesse de deplacement faible. Il est ainsi possible d’analyser les structures canalaires lymphatiques sans aucune injection de produit de contraste. Les lymphatiques retroperitoneaux, la citerne de Pecquet, le canal thoracique sont tres regulierement visualises. Il est donc possible en lymphographie par resonance magnetique d’obtenir une representation anatomique de bonne qualite des structures lymphatiques thoraciques. La lymphographie par resonance magnetique peut egalement etre utilisee pour le bilan etiologique des chylothorax, l’evaluation des lymphangiomes kystiques thoraciques ou pour certaines maladies lymphatiques complexes interessant la region thoracique. Il faut cependant signaler qu’il s’agit d’une technique en devenir dont les resultats s’amelioreront avec les progres technologiques des systemes d’IRM.

There are many limitations to the examination of the bile ducts by magnetic resonance imaging, which may be four orders: (1) technical, requiring analysis of Maximum Intensity Projection (MIP) three-dimensional (3D) volume reconstructions as well as native images, the use of T1-weighted sequences obtained in 3D to avoid entry slice phenomena, and knowledge of the inherent limits of the method, the spatial resolution of which is still less than optimal; (2) anatomical: you need to know the appearance of flow artefacts within the bile ducts and the traps that the presence of air or bleeding into the bile ducts can create; you also need to know the characteristic appearance of the indentation caused by the hepatic artery on the bile ducts and the variants and modifications seen in cases of portal biliopathy; (3) semiological: the terms used to describe bile duct abnormalities seen in MRI are often derived from imprecise descriptions used in retrograde cholangiography: irregularities of the bile ducts, a beaded ‘string of pearls’ appearance, a ‘dead tree’ appearance; (4) related to a complex disease, cholangitis which is a complex pathological condition, with possible overlaps between different conditions, such as primary sclerosing cholangitis (PSC), secondary sclerosing cholangitis, autoimmune cholangitis. In any case, the diagnosis of cholangiocarcinoma associated with PSC is always difficult. These limitations can be circumvented by using a precise exploration technique comprised of 3D magnetic resonance cholangiography sequences, which allow volume analysis, examination of native slices and of thick or thin MIP reconstructions, and heavily T2-weighted and T1-weighted 3D sequences with and without gadolinium injection, which is not always essential. The examination must be interpreted according to a stereotyped plan that includes (1) examination of the bile ducts, searching for and describing any stenosis, the presence or absence of dilatation, (2) a systematic search for any intrahepatic calculus, (3) examination of the heterogeneity of the liver parenchyma, investigation to find any liver dysmorphia and signs of portal hypertension, (4) analysis of the enhancement of the liver parenchyma and any enhancement of the wall of the bile ducts.

Resume L’angiomyolipome est une tumeur mesenchymateuse benigne du groupe des PEComes, qui comprend trois composantes en proportion variable : tissu adipeux, cellules musculaires lisses et vaisseaux sanguins. La localisation hepatique est rare, moins de 300 cas ayant ete decrits dans la litterature. En fonction de la composante tissulaire predominante, l’angiomyolipome hepatique peut prendre differents aspects en imagerie et etre pris a tort pour un carcinome hepatocellulaire ou une autre lesion hepatique benigne. Les criteres diagnostiques de l’angiomyolipome hepatique sont une tumeur bien limitee, non encapsulee, avec contingent graisseux, hypervasculaire avec prise de contraste persistante, siege de larges vaisseaux intratumoraux se drainant dans une veine hepatique. En raison des risques hemorragique, de recidive et de transformation maligne, tous tres rares, le traitement de reference est la resection chirurgicale. A partir d’une serie de quatre angiomyolipomes hepatiques operes ayant tous beneficie d’une IRM hepatique preoperatoire, nous decrirons les principaux aspects rencontres en imagerie.

Imaging of the postsurgical spine Some early complications (hematoma, spondylodiscitis, pseudomeningocele) can occur with all types of surgery while late complications vary with the type of surgery. After discectomy, postsurgical changes (osseous and ligamentous defects, scar tissue, granulation tissue) should be distinguished from postsurgical complications or recurrent disease (recurrent disc herniation, arachnoiditis, spondylodiscitis). Following spinal decompression and fusion procedures, standard radiographs and CT can confirm the adequate position of the fusion devices, the presence of fusion, and the development of late osseous complications: pseudarthrosis, instability and recurrent stenosis.

Cross-sectional imaging of peripheral involvement in ankylosing spondylitis Ankylosing spondylitis is the most common spondyloarthropathy. It is characterized by enthesopathy (inflammation at the insertion of ligaments, tendons or fascia to bone). The os calcis is most frequently involved. Additional peripheral manifestations include synovitis and dactylitis. Unlike radiographs that demonstrate late manifestations of the disease, ultrasound and MRI demonstrate early inflammatory changes of bones and soft tissues. Multiple sites of involvement may also be detected on a single examination. Both imaging modalities facilitate early diagnosis, a crucial element for patient management. Both modalities may also monitor lesion regression during treatment.

Resume L’imagerie du foie aujourd’hui est composee de methodes qui n’existaient pas il y a 40 ans, tandis que celles de l’epoque ont presque entierement disparu. Le developpement de l’echographie, de la tomodensitometrie (TDM), de l’imagerie par resonance magnetique (IRM) et de la tomographie par emission de positons (TEP) a ete rapide sur le plan technologique, precedant parfois et orientant souvent la strategie medicale. Aujourd’hui, leur programme initial, c’est-a-dire la morphologie pour les trois premieres et l’information metabolique pour la derniere, est parvenu a maturite ; la place est a la reflexion medicale, aux recommandations et a la standardisation. Pourtant, la marche en avant du progres technique n’a pas cesse. Elle va maintenant vers d’autres horizons : l’imagerie fonctionnelle par echographie, TDM ou IRM (la perfusion des tumeurs et des parenchymes), l’imagerie structurale (l’IRM de diffusion de la fibrose et des tumeurs, l’analyse de texture du foie en echographie et en TDM, la spectroscopie), l’imagerie « multimetabolique » (les nouveaux traceurs en TEP). Cette imagerie approche aussi la cellule, voire la molecule. Enfin, toutes les methodes vont combiner leurs forces pour devenir hybrides, soit par la construction de nouvelles machines (TEP-IRM), soit par le developpement de la fusion d’images. On peut anticiper que ce nouveau savoir induira un remodelage des frontieres des specialites.

PURPOSE To evaluate clinical and ultrasound (US) results following percutaneous repair of the Achilles tendon. MATERIALS AND METHODS Thirty-four patients underwent percutaneous Achilles tendon repair between 2004 and 2006. Seventeen patients (11 males and 6 females aged 30 to 59 years) underwent clinical and US follow-up at a mean of 15 months. US evaluation included assessment of the bilateral Achilles tendons with recording of maximum tendon diameter, echotexture, and presence of intratendonous neovascularization on power Doppler US. RESULTS On clinical evaluation, all patients were satisfied with the outcome and able to resume their normal level of activity. On US evaluation, there was no tendon discontinuity, and all tendons showed hypoechoic thickening with mean maximal diameter of 13 mm. Focal changes in echotexture were noted in 11 patients, hypoechoic in 5 cases and echogenic in 6 cases. A normal fibrillar echotexture was noted in 5 cases, at more than on eyear after surgery. Intratendonous neovascularization was present in 10 cases, mild in 6 cases, moderate in 2 cases and marked in 2 cases. The degree of neovascularization decreased with increasing postsurgical time. CONCLUSION Postsurgical Achilles tendons were characterized on US by hypoechoic thickening and loss of normal fibrillar echotexture. The presence of intratendonous neovascularization probably corresponds to postsurgical scarring that decreases over time.

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.

Resume Objectif Determiner les valeurs de l’epaisseur parietale et du diametre externe de l’appendice normal au scanner multibarrette. Materiels et methodes Un radiologue senior, n’ayant pas connaissance de l’histoire chirurgicale du patient, a examine prospectivement les scanners abdomino-pelviens de 57 patients adultes consecutifs non suspects d’appendicite. La plupart des patients (50/57) ont eu une injection iodee intraveineuse. Mais aucun n’a eu d’opacification digestive. Toutes les coupes (1 et 5 mm) et les reconstructions multiplanaires etaient analysees sur une console de traitement. Le diametre externe de l’appendice, l’epaisseur des deux parois appendiculaires, et la presence ou non de gaz intraluminal etaient notes. Resultats L’appendice a ete visualise dans 82 % des cas (47/57). Le diametre externe moyen etait de 6,7 mm ± 1,2 (echelle de 5,0 a 11,0 mm). L’epaisseur moyenne des deux parois etait de 4,8 mm ± 1,0 (echelle de 2,6 a 6,4 mm). L’air intraluminal etait visualise dans 87 % des cas (41/47). Conclusion Contrairement au diametre externe, l’epaisseur biparietale de l’appendice normal en ne depassant quasiment pas le seuil de 6 mm semble une mesure fiable pour identifier un appendice normal au scanner multibarrette.

Resume Objectif Determiner si le scanner multi detecteurs aide au diagnostic positif et etiologique en cas de perforation d’ulceres gastro duodenaux. Materiel et methodes Analyse prospective des donnees scanographiques avec reconstructions multi planaires de 15 patients consecutifs, ayant eu une perforation d’ulcere gastrique ou duodenal. Nous avons recherche les signes suivants : pneumoperitoine, epaississement parietal, discontinuite parietale, epanchement intra peritoneal, densification de la graisse peritoneale. Resultats Tous les patients avaient une perforation d’ulcere gastro duodenal. Le pneumoperitoine etait systematiquement present au scanner, alors que l’ASP le montrait chez 3 patients sur 9. La breche parietale a pu etre visualisee chez 53 % des 15 patients (8/15), alors que l’origine de la perforation etait supposee dans les autres cas, devant des signes indirects de perforation (anomalie parietale, localisation du pneumoperitoine) Dans 25 % des cas (2/8), la breche parietale, non visible sur les coupes axiales, etait visible sur les reconstructions multi planaires. Conclusion En cas de suspicion de perforation d’organe creux ou de tableau clinique indetermine de douleurs epigastriques, le scanner multi detecteurs avec reconstructions multi planaires permet le diagnostic positif et etiologique de perforation d’ulcere gastro duodenal.

Resume Correlation radiologique et pathologique chez un jeune homme porteur d’un diverticule intra-luminal du deuxieme duodenum revele par une pancreatite aigue. Le diagnostic repose sur les donnees endoscopiques et scanographiques. L’examen anatomo-pathologique permet de faire le diagnostic differentiel avec un choledochocele.

Purpose To compare fotemustine and dacarbazine (DTIC) in terms of overall response rate (ORR) as primary end-point and overall survival, duration of responses, time to progression, time to occurrence of brain metastases (BM), and to assess safety and quality of life in patients with disseminated cutaneous melanoma. Patients and Methods Patients received either intravenous fotemustine 100 mg/m2 weekly for 3 weeks or DTIC 250 mg/m2/d for 5 consecutive days every 4 weeks (two cycles). Nonprogressive patients received a maintenance treatment every 4 weeks (fotemustine 100 mg/m2 or DTIC 250 mg/m2 for 5 days). Results Two hundred twenty-nine patients were randomly assigned to fotemustine or DTIC arms. The best ORR was higher in the fotemustine arm than in the DTIC arm in the intent-to-treat population (n = 229; 15.2% v 6.8%; P = .043) and in full analysis set (n = 221) (15.5% v 7.2%; P = .053). Similar median durations of responses (5.8 months with fotemustine v 6.9 months with DTIC) and time to progression (1.8 v 1.9 months, respectively) were observed. In patients without BM at inclusion, the median time to BM was 22.7 months with fotemustine versus 7.2 months with DTIC (P = .059). Median survival was 7.3 months with fotemustine versus 5.6 months with DTIC (P = .067). The main toxicity was grade 3 to 4 neutropenia (51% with fotemustine v 5% with DTIC) and thrombocytopenia (43% v 6%, respectively). No significant difference was noted for quality of life between arms. Conclusion ORR was higher in the fotemustine arm compared to the DTIC arm in first-line treatment of disseminated melanoma. A trend in favor of fotemustine in terms of overall survival and time to BM was evidenced.

Resume La fracture du cartilage costal est une lesion traumatique rare mais dont la frequence est probablement sous-estimee. Cette lesion, non visible sur les radiographies, est pourtant de diagnostic simple en echographie, en tomodensitometrie et en IRM. Nous rapportons ici un cas de douleur parietale anterieure post-traumatique survenue chez un judoka.

We report the MRI findings of six unusual lesions of the internal auditory canal: three haemangiomas, one lipoma, one metastasis and one traumatic neuroma. We compare the findings to those of 20 intracanalicular schwannomas. We noted the site and size of the tumour, its signal intensity, borders and the homogeneity of enhancement were studied on T1-weighted images before and after intravenous contrast medium and T2-weighted images. Most schwannomas were homogeneous lesions, isointense on T1- and T2-weighted images, and strongly enhancing. Spontaneous high signal on T1-weighted images, heterogeneous contrast enhancement and extranodular enhancement were helpful for recognising lesions other then schwannomas; site, size and signal on T2-weighted images were not. All the haemangiomas had a specific pattern of contrast enhancement, with an anterior core intensely enhancing portion and a posterior portion which enhanced moderately or not at all.

PURPOSE: To evaluate the ability of magnetic resonance (MR) imaging enhanced with AMI-25 to depict and characterize hepatic tumors. MATERIALS AND METHODS: Sixty-four patients (41 men and 23 women, aged 24-65 years [mean, 55 years]) underwent 1-T MR imaging: 22 had metastatic disease; 10, hepatocellular carcinoma; seven, hemangioma; three, focal nodular hyperplasia; three, gallbladder adenocarcinoma; two, lymphoma; one, adenoma; and 16, no tumor. Pre- and postcontrast images (alone and in combination) were analyzed by three independent radiologists. Receiver operating characteristic curves were constructed to compare tumor characterization. RESULTS: Signal intensity was decreased in all benign tumors but not in malignant tumors. The number of tumors depicted (nonenhanced images, 657 tumors; enhanced, 753; and combined, 760) was not statistically different. Receiver operating characteristic curves did not show improved characterization with AMI-25. CONCLUSION: AMI-25 does not improve depiction of hepatic tu...

Radiation therapy of malignant neoplasms of the anal canal has promising results in the majority of patients if the disease is limited at initial diagnosis. Computed tomography (CT), especially when performed with contrast material injected intravenously, is valuable in the pre- and posttreatment assessment of the anorectal musculature and perirectal nodes. The authors review the anatomy of the anorectal area and their experience with CT evaluation of anal canal cancer in a series of 26 patients. They also discuss their experience with treatment of this cancer in a series of 48 patients.

To assess the role of contrast-enhanced helical CT in the evaluation of tumour vascularity in endocrine pancreatic tumours (EPTs), and to determine the predictive factors of malignancy of EPTs at helical CT with CT-histopathological correlation.Thirty-seven consecutive patients with histopathologically proven EPTs underwent dual-phase helical CT. For each tumour detected, its density relative to the surrounding parenchyma was scored on the pancreatic phase using a 5-point scale. Radiological findings were correlated with histopathological (vessel density count) and clinical follow-up findings.Thirty of 37 patients had non-functioning EPTs and overall 44 tumours were detected by helical CT (mean size 38, range 5-100 mm). CT showed calcifications in 10 tumours. Calcifications were associated with well-differentiated carcinomas (90%, p = 0.02). Vascular density assessed by light microscopy was significantly correlated with tumour enhancement at the pancreatic phase (p = 0.0001). Poorly differentiated carcinomas were less vascularised than well-differentiated tumours and carcinomas (34 vs. 264 vessels/mm2, p = 0.0073). Tumour differentiation also correlated with tumour enhancement at the pancreatic phase (p = 0.0044, trend test): poorly differentiated carcinomas were hypoattenuating (71%) and isoattenuating or weakly hyperattenuating (29%), compared with well-differentiated carcinomas and tumours that were mainly moderately or strongly hyperattenuating (53%). In univariate analysis, poor tumoral differentiation, hepatic metastasis, high mitotic index, poor tumoral enhancement at the pancreatic phase and less vascularised tumours were correlated with decreased survival rate.Enhancement of EPT at CT is correlated with tumour vascularity assessed by light microscopy. Low-enhancing EPT at CT are correlated with poorly differentiated EPT and with a decrease in overall survival.

Scar endometriosis is a rare disease which is difficult to diagnose. The symptoms are nonspecific, typically involving abdominal wall pain at the time of menstruation. Clinical examination may reveal a painful nodule, if the scar involved is located on the abdominal wall, but is normal, when the lesion is located on the uterine scar. Other means of investigation (transvaginal ultrasonography, computed tomography) may be useful in case of lesions on the abdominal wall, or if the nodule is large, but give no specific results. The diagnosis is frequently made only after excision of the lesion. We report here 4 patients operated for scar endometriosis (two abdominal and two uterine scars) for whom MRI had suggested the diagnosis. Thanks to its very high spatial resolution, MRI enables very small lesions to be detected and can distinguish the hemorrhagic signal of endometriotic lesions. Furthermore, it performs better than the CT scan in detecting the limits between muscles and abdominal subcutaneous tissues.

Study Objective. To take recent progress in magnetic resonance imaging (MRI) into account to determine its accuracy compared with that of transvaginal ultrasonography (TVUS) in diagnosing bladder endometriosis. Design. Retrospective analysis (Canadian Task Force classification II-2). Setting. University-affiliated hospital. Patients. Twelve women with histologically proved bladder endometriosis. Intervention. Magnetic resonance imaging with body and endocavitary coils and TVUS. Measurements and Main Results. Although TVUS was normal in four patients, MRI enabled endometriotic lesions to be detected in all patients. Magnetic resonance imaging with endocavitary coil established the existence of deep infiltration in three patients when muscularis involvement was not visible with the body coil. In seven women MRI determined how far deep posterior endometriotic lesions extended, whereas with TVUS this was impossible to see. Conclusion. MRI had advantages over TVUS in diagnosing small lesions of associated posterior deep endometriotic lesions. The endocavitary coil gave better results than the phased-array coil for diagnosing deep infiltration. These results are important in that they help guide surgical management.

es rhabdomyolyses post operatoires sont des entites bien connues des anesthesistes. Elles sont en effet liees a la compression musculaire prolongee durant de longues interventions effectuees dans certaines positions operatoires, et peuvent etre responsable d’insuffisance renale aigue. Nous rapportons un cas de rhabdomyolyse des muscles erecteurs du rachis, plus communement appeles spinaux, diagnostique sur un scanner dans les suites d’une gastrectomie.

The efficiency, accuracy, and safety of ultrasound-guided liver biopsy with plugging of the needle track were prospectively assessed in 72 patients at high risk for hemorrhage. Seventy-eight biopsy procedures were performed in 72 consecutive patients prospectively classified into four different groups on the basis of coagulation parameters. Sixty-two patients (86%) had severe or moderately severe coagulation disorders. Fifty-four biopsy procedures were performed in 50 patients with diffuse liver disease, and 24 were performed in 24 patients with focal liver lesions. The biopsy track was embolized with gelatin particles and thrombin. Biopsy specimens adequate for histologic diagnosis were obtained in 69 of the 72 patients (96%). In focal lesions, accuracy and sensitivity in the diagnosis of malignancy were 75% and 89%, respectively. Two serious bleeding complications (2.8%) were encountered in two of the patients with major coagulation disorders. Liver biopsy with plugging of the needle track is a practical technique and is a feasible alternative to the transjugular approach. Respective indications for both methods depend on the severity of coagulation disorders and the presence of focal lesions.

The aim of this study was to describe the intrahepatic hemodynamic modifications induced by right portal vein embolization (RPVE) using Doppler ultrasound. Eighteen patients with hepatocellular carcinoma (n = 8), liver metastases (n = 9), or multiple adenomas, underwent RPVE 1 month before right hepatectomy in order to increase the size of future remnant liver. Doppler ultrasound was performed before and 1 month after RPVE. The portal vein flow and the hepatic artery resistive index in right and left lobes (segments V and III) were calculated. We recorded simultaneously artery and portal vein of segment III to measure the arterioportal ratio calculated as follows: (maximal arterial systolic velocity minus maximal portal vein velocity)/maximal arterial systolic velocity. Results were compared in cirrhotic patients (group A) and in healthy liver patients (group B). In both groups, portal flow was not significantly modified following RPVE. In the left lobe, in both groups the hepatic artery resistive index was not significantly modified. In group B, the arterioportal ratio decreased significantly (0.71 +/- 0.18 and 0.42 +/- 0.23, respectively, before and after embolization; p0.01), whereas it was not statistically modified in group A (0.75 +/- 0.17 and 0.69 +/- 0.14, respectively, before and after embolization). The right hepatic arterial resistive index decreased significantly in both groups after embolization (0.74 +/- 0.07 to 0.66 +/- 0.07, p0.05; and 0.66 +/- 0.07 to 0.61 +/- 0.06, p0.05, respectively, before and after RPVE for groups A and B). Total portal flow was unchanged after RPVE (750 +/- 337 ml/mn and 696 +/- 231 ml/mn, respectively, before and after RPVE). The hepatic artery resistive index was unchanged before and after embolization in the left lobe (0.75 +/- 0.13 and 0.74 +/- 0.14, respectively), but significantly decreased in the right lobe (0.7 +/- 0.08 and 0.62 +/- 0.06 respectively, p0.05). The left arterioportal ratio decreased significantly from 0.76 +/- 0.17 to 0.52 +/- 0.23 after PVE, p0.02). Our study confirms that right portal occlusion induces a decrease in hepatic artery resistive index in the right lobe and does not modify total portal flow. The left and right lobes of the liver have separate arterioportal regulation.

OBJECTIVE: Our goal was to assess the usefulness of helical CT in the presurgical evaluation of hilar cholangiocarcinoma. CONCLUSION: Helical CT aids in tumor localization and in assessment of parenchymal, biliary intrahepatic, and portal involvement in hilar cholangiocarcinoma. However, helical CT is not effective in the assessment of biliary extrahepatic, arterial, and lymph node involvement.

Despite the advancements of CT and MR imaging, ultrasonography (US) has continued to improve and to develop as well as to have enormous applications, implications, and importance in diagnostic imaging of the liver. While gray-scale imaging has improved significantly, so that the definition of subtle lesions only a few millimeters in size is now possible, recent years have seen the most exciting advances in Doppler US technology. The development of power Doppler imaging has substantially improved perception of tumor vascularity. The introduction of US contrast media in combination with harmonic imaging has even further enlarged the potential uses of this technique. This article explores the most recent advances in gray-scale and Doppler US of the liver, with emphasis on their clinical applications for the study of hepatocellular carcinoma (HCC). US currently plays a fundamental role in the diagnostic and therapeutic management of patients with HCC.

The liver is the largest organ in the body. It occupies much of the right hypochondrial region of abdomen. Its left lobe extends across the epigastrium and projects a variable distance into the left hypochondrium. The liver has two major surfaces, a superior or diaphragmatic surface and an inferior or visceral surface. They are separated anteriorly and laterally by a sharply angled inferior margin. The diaphragmatic surface is highly convex, since it is molded by the inferior aspects of the diaphragm.