Primary lower limb lymphoedema: classification with non-contrast MR lymphography.

PURPOSE: The purpose of the present study was to analyse the performance of non-contrast MR lymphography for the classification of primary lower limb lymphoedema in 121 consecutive patients with 187 primary lower limb lymphoedemas. MATERIALS AND METHODS: 121 consecutive patients with clinically diagnosed primary lower limb lymphoedema underwent non-contrast MR lymphography with a free-breathing 3D fast spin-echo sequence with a very long TR/TE (4000/884 ms). MR examinations were retrospectively reviewed for severity of lymphoedema (absent, mild, moderate, severe) and characteristics of inguinal lymph nodes and iliac and inguinal lymphatic trunks graded as aplasic (no lymph nodes or lymphatic trunks), hypoplasic (less lymph nodes or lymphatic trunks), normal and hyperplasic (more lymph nodes or more and/or dilated trunks). RESULTS: There was an excellent correlation between clinical stage and severity of lymphoedema (Cramer's V of 0,73 (p < 0.001)). Differentiation was feasible between inguinal lymphatic vessel aplasia (21%), hypoplasia (15%), normal pattern (53%) and hyperplasia (11%). Severe lymphoedema was observed in 46% of aplasic patterns and in 37% of hyperplasic patterns, but in only 15% of hypoplasic patterns and never observed in normal patterns (p < 0.001). CONCLUSION: Non-contrast MR lymphography is able to classify primary lower limb lymphoedemas into hyperplasic, aplasic, hypoplasic and normal patterns. KEY POINTS: • Non-contrast MR lymphography is able to classify primary lower limb lymphoedemas. • Lymphoedema can be classified in hyperplasic, aplasic, hypoplasic and normal patterns. • Non-contrast MR lymphography can optimize clinical management of primary lower limb lymphoedemas.

MRI of cholangitis: traps and tips.

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.

[Diffusion-weighted MR imaging of liver pathology: principles and clinical applications]. / Imagerie par résonance magnétique de diffusion (IRMD) en pathologie hépatique: principe et applications cliniques.

Due to ongoing technological advances, the range of clinical applications for diffusion-weighted MR imaging has expanded to now include abdominal pathology. Current applications for liver pathology include two main directions. First, oncologic imaging with detection, characterization and follow-up of lesions. Second, evaluation of diffuse liver diseases, including hepatic fibrosis. The diagnostic impact and role of diffusion-weighted MR imaging remain under investigation, but appear promising. Because of its short acquisition time, sensitivity, and additional information it provides, diffusion-weighted MR imaging should be included in routine liver imaging protocols.

[Imaging of incidental cystic lesions of the pancreas]. / Imagerie des lésions kystiques du pancréas de découverte fortuite.

Cystic lesions of the pancreas, with an estimated prevalence of 20%, frequently are incidental findings at imaging on asymptomatic patients. Pseudocysts, typically in a setting of pancreatitis, should first be excluded. Characterization of cystic tumors is more complicated. Still, it is important to differentiate between benign and malignant lesions. Multi-detector row CT and MRI allow characterization of such lesions in over 75% of cases. Indeterminate lesions should undergo endoscopic US with biopsy/aspiration and fluid analysis, especially for mucin producing tumors (rounded with thick enhancing wall). When imaging fails to fully characterize a lesion, follow-up may be proposed for lesions less than 3 cm in size, that are either unilocular with thin nonenhancing wall (simple cyst) or lobulated multilocular with thin nonenhancing wall (serous cystadenoma, isolated side branch IPMTP). Follow-up imaging shows that these tumors usually show very little change over time. Management is based on comparing estimated patient survival without treatment to surgical risks (morbidity, mortality, functional sequelae from the procedure).

[Pineapple juice as a negative oral contrast agent in magnetic resonance cholangiopancreatography]. / Utilisation du jus d'ananas en tant qu'agent de contraste négatif en cholangiopancréatographie par résonance magnétique*

PURPOSE: The quality of magnetic resonance cholangiopancreatography (MRCP) images is frequently degraded by high signal from the gastrointestinal tract on heavily T2W images. The purpose of this study is to evaluate pineapple juice (PJ) as an oral negative contrast agent in MRCP. MATERIALS AND METHODS: Results from MRCP in 50 patients with PJ and 50 patients with paramagnetic contrast (ferumoxsil-Lumirem) were compared. Reviewers were blinded to the type of contrast agent. Exam quality was recorded with regards to signal suppression in the stomach, duodenum and proximal small bowel and with regards to pancreatic duct and biliary ducts visualization. In vitro, the signal characteristics of several commercially available brands of PJ were assessed using T1W, T2W and MRCP sequences. Signal intensity was correlated with the manganese concentration measured using atomic absorption spectrometry. Finally, the reviewers compared the taste of PJ and ferumoxsil. RESULTS: On MRCP sequences, results were similar with regards to signal suppression in the stomach, duodenum and proximal small bowel with PJ and ferumoxsil. Visualization of the pancreatic duct, intrahgepatic bile ducts and CBD was similar with PJ and ferumoxsil. The signal intensity of commercially available brands of PJ on T2W and MRCP sequences correlated well with the measured manganese concentration on spectroscopy. Variations in manganese concentration were observed, with values ranging from 3.65 to 27.24 mg/L. The reviewers noted that PJ tasted "good" or "very good" and that ferumoxsil tasted "bad" or "very bad". CONCLUSION: Ingestion of PJ provides effective signal suppression in the GI tract on MRCP, similar to paramagnetic contrast agents. Because manganese concentration is highly variable in commercially available PJ brands, a brand with high manganese concentration should be selected.

MR lymphography of abdominal and retroperitoneal lymphatic vessels.

OBJECTIVE: The abdominal and retroperitoneal lymphatic system is characterized by numerous anatomic variations. Our objective is to review MR lymphographic features of normal anatomy and abnormal conditions. CONCLUSION: MR lymphography is a noninvasive technique that is well suited for the examination of abdominal and retroperitoneal lymphatic vessels.

[Imaging of thoracic pathology in patients with AIDS]. / Imagerie des pathologies thoraciques chez le patient VIH au stade sida.

The imaging features of infectious and non-infectious pathologies in HIV patients with AIDS (less than 200 CD4/mm3) are illustrated. Opportunistic infections, tumors and vascular pathologies have variable appearances based on the degree of immunosuppression and patient compliance with opportunistic infection prophylaxis. Because of advances in retroviral treatments and wider use of anti-infectious prophylaxis, thoracic pathologies in AIDS patients are less frequent but must nonetheless be recognized, and diagnosis should be suggested in patients with unknown serologic status.

Acute abdominal aortic thrombosis in cancer patients.

We report two cases of acute aortic thrombosis in cancer patients. Aortic thrombosis is rare in the absence of atherosclerosis, dissection, or aneurysm. On the one hand, hypercoagulable state related to cancer is a well-known risk factor for venous thrombosis. On the other hand, arterial thrombosis has been rarely reported in cancer patients. Recognition of aortic thrombosis is important because it is a dangerous condition; furthermore, it exposes at the patient to complications such as peripheral embolism. In addition, anticoagulation can result in resolution of thrombosis.

[Post-traumatic intramural hematoma of the colon]. / Hématome intramural colique post-traumatique.

Intramural hematoma of the colon is a rare complication of blunt abdominal trauma. We report the case of a 32-year-old man who presented with abdominal pain related to blunt trauma. The initial diagnosis of post-traumatic intramural hematoma of the colon was performed at CT scan and proven at colonoscopy. Although the majority of cases warrant surgery, conservative therapy was proposed in the present case with spontaneous resolution of the hematoma demonstrated by CT scan.

[D-Dimer determination combined with clinical probability for the diagnosis of leg venous thrombosis]. / Association en pratique clinique du dosage des D-Dimères et d'une probabilité clinique pour le diagnostic de thrombose veineuse des membres inférieurs.

OBJECTIVE: To evaluate the results of combination of D-Dimer test and simple clinical model for the diagnosis of deep vein thrombosis (DVT). MATERIALS AND METHODS: Inclusion: clinical suspicion of DVT. Non inclusion criteria were Clinical model performed by the referring physician included probability varying from high to low. D-Dimer test was performed by five different rapid techniques. Standard of reference was Doppler ultrasonography (DU) performed by a senior radiologist. RESULTS: Eight hundred and fifty-four DU were performed on a 14 months time period, including 206 suspicion of pulmonary embolism, 109 postoperative time period, 120 non-included or excluded patients, 278 incomplete observations, 141 complete observations. DVT was present in 33 cases and absent in the other 108 cases (prevalence 23%). Sensitivity and negative predictive value of the five tests were between 82 and 97% and 90 et 97%. The most sensitive test had a specificity of 36% and a positive predictive value of 32%. Combination of clinical model and D-Dimer test did not improve the diagnostic accuracy. CONCLUSION: None of the test evaluated in the present study, even when combined with the clinical model results, did allow the exclusion of DVT.

Long-term follow-up after neoplastic seeding complicating percutaneous ethanol injection for treatment of hepatocellular carcinoma.

We describe a case of subcutaneous metastasis along the needle track after percutaneous ethanol injection (PEI) for treatment of hepatocellular carcinoma. After surgical resection and extrabeam radiation therapy the patient is alive without evidence of recurrence five years after PEI. One should pay attention to the abdominal wall around the needle track in interpreting CT or MR images of patients with previous PEI.

Characteristics of missed lung cancer on chest radiographs: a French experience.

The purpose of this study was to report 30 cases of missed lung cancers and describe characteristics of each case. Reasons for misdiagnosis were analyzed from the report. Each radiograph was subsequently reviewed by a panel of two experts who quantified several parameters regarding image analysis and film quality. Lesions were not described in 67% of the cases and were misinterpreted as benign processes in 33% of cases. Comparison to previous chest radiographs and clinical information were seldom available on the report. Size of the lesions varied between 1 and 7 cm, location was primarily apical and paramediastinal, normal anatomy was highly or moderately complex in 87%, and distracting lesions were present in 63% of the cases. Image quality was considered perfect in 3 cases only. Among all the factors responsible for missed lung cancer, certain factors can be improved as film quality, comparison with previous radiographs, and better awareness of clinical information.

[Imaging mechanical complications of inferior vena cava filters]. / Imagerie des complications mécaniques des filtres caves inférieurs.

Filter placement within the inferior vena cava is performed to prevent pulmonary embolism in patients with contraindications or failure of anticoagulant therapy. Several complications of vena cava filters have been described. However, mechanical complications related to IVC filters may not be of any clinical significance. The purpose of this pictorial essay is to present the imaging features of complications related to inferior vena cava filter placement.