[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).

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.

[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.

[Solitary fibrous tumor of the liver]. / Tumeur fibreuse solitaire du foie.

Solitary fibrous tumor (SFT) is commonly found on serosal surfaces, and is rarely localized in the liver. There are benign and malignant variants of hepatic SFT. We report a new case of benign SFT. Our patient, a 63-year old woman, who has been followed for 5 years for an asymptomatic liver mass, was admitted for abdominal pain. Ultrasonography (US), CT, MR Imaging and angiography showed the liver mass with typical imaging features, situated in the right hepatic lobe with blood supply from the hepatic artery. Histopathological examination demonstrated a highly vascularized tumor, composed of short spindle cells alternating with hypocellular collagenous regions, with a hemangiopericytoma-like vascular pattern. The immunohistochemical staining was positive for CD 34. Tumor resection was performed. Follow-up 8 years after the resection showed no tumor recurrence or metastasis, thus confirming the initial diagnosis of benign SFT.

[External phased-array MR imaging preoperative assessment of rectal cancer]. / Bilan pré opératoire des cancers du rectum en IRM pelvienne haute résolution avec antenne en réseau phasé.

The main problem associated with rectal cancer treatment is tumor recurrence. Randomized controlled studies have shown that adjuvant preoperative radiation therapy is effective for reducing local recurrence. These studies have also demonstrated that there are groups of rectal cancer patients with differing degrees of risk for local recurrence. At one end of the spectrum is the low-risk group: patients with superficial rectal cancer, who can be treated with surgery alone. At the other end is the high-risk group: patients with a close or involved resection margin at total mesorectal excision, the very advanced tumors that require a longer course of chemotherapy and radiation therapy, and extensive surgery. Paramount for this selection and differentiated treatment is a reliable preoperative test that can be used to distinguish these groups of patients. In this review article, we will discuss the role of high-resolution phased array MRI among the other imaging modalities such as endorectal MRI, endorectal US, and CT. We will also discuss and illustrate MR imaging results in terms of T stage, circumferential resection margin, locally advanced rectal cancer, and N stage.

Extraskeletal mesenchymal chondrosarcoma: case report and review of the literature.

A case of extraskeletal mesenchymal chondrosarcoma in a 62-year-old woman is reported. This unusual sarcoma was localized in the right thigh (quadriceps) and treated with a combination of surgery, chemotherapy and radiotherapy. Sixty-three cases were found in the literature, with neurologic localization in 29 cases and muscular localization in 34 cases. Among clinical features, a significant difference in age at the time of diagnosis was found between the two localizations, which strongly suggests the possibility of two different types of extraskeletal mesenchymal chondrosarcoma.

[Imaging features of iatrogenic drug disorders]. / Imagerie de la pathologie iatrogène médicamenteuse.

Iatrogenic drug disorders should be considered when presented with a number of imaging findings mainly involving the nervous, musculoskeletal, gastrointestinal or genitourinary system. Care should be used when differentiating between imaging findings related to the underlying pathology and imaging findings related to drug-related complications: examples include the impact of steroid therapy on bones and the impact of triple-drug anti-HIV therapy and its impact of fatty tissue. Knowledge of the necessary imaging surveillance protocol is implied.

[Reactive synovitis: MRI features with arthroscopic correlation]. / Synovites réactionnelles: aspects en IRM et corrélations arthroscopiques.

OBJECTIVES: To evaluate MR imaging in detecting and characterizing secondary reactive synovitis and correlate the results with arthroscopy. MATERIALS AND METHODS: Retrospective study of 10 patients referred for MR imaging and arthroscopy of the knee or shoulder. The diagnosis of reactive synovitis was confirmed by arthroscopy and pathological examination. Synovial thickening was graded at MRI as follows. Grade 0: normal; grade 1: diffuse synovial thickening; grade 2: nodular synovial hypertrophy; grade 3: pseudotumoral synovial mass. RESULTS: Synovitis was described at MRI in 8 cases. There were 2 false negative results on MR imaging for the knee. Synovitis was secondary to knee trauma and rotator cuff tear or surgery of the shoulder. On arthroscopy, all synovial lesions were detected and confirmed at pathology. Synovitis was not detected at MRI (grade 0) in 20% of cases. Synovitis appeared diffuse (grade 1) in 30%, nodular (grade 2) in 30% and pseudotumoral (grade 3) in 20%. Bony erosions were adjacent to synovial thickening in 5 cases. CONCLUSION: Reactive synovitis can occur after trauma. MR imaging is useful in detecting and evaluating secondary reactive synovitis. Arthroscopy and synovial biopsy are necessary to exclude infectious or tumoral synovitis.

Intractable hiccups: the role of cerebral MR in cases without systemic cause.

PURPOSE: To look for central nervous system abnormalities as possible causes of intractable hiccups. METHODS: Of a series of 50 patients with chronic (ie, lasting more than 48 hours) hiccups, a prospective study identified a subgroup of 9 patients with no clinical or gastroesophageal abnormalities (according to endoscopy, pH monitoring and manometry). We performed in all 9 patients brain and upper cervical cord MR examination with precontrast and postcontrast T1- and T2-weighted sequences. A study of the last cranial nerves was done with thin T2-weighted imaging (constructive interference in a steady state sequence). The cervical cord and parapharyngeal space were systematically explored using coronal T2- and sagittal T1-weighted imaging. RESULTS: Five of these 9 patients had definite MR abnormalities located in the temporal lobe (3 cases), cerebellopontine angle (1 case), or areas of high signal intensity compatible with demyelination (1 case). The relationship between hiccups and infratentorial abnormalities in 2 cases was doubtful (vascular loop and prominent posterior condylar canal). MR findings in 2 cases were considered normal. CONCLUSIONS: Brain MR is a useful investigation in patients with chronic hiccups when gastroesophageal lesions are either excluded or too mild to account for an intractable hiccup.

Intracranial dural arteriovenous fistulas with spinal venous drainage: relation between clinical presentation and angiographic findings.

PURPOSE: To investigate why some patients with an intracranial dural arteriovenous fistula (DAVF) with spinal venous drainage have myelopathy and others do not. METHODS: We reviewed the clinical and radiologic data for 12 patients who had a DAVF with spinal venous drainage diagnosed at our institutions from 1982 to 1995. RESULTS: Six patients had progressive spinal cord indications of disease (patients with myelopathy) and six others (patients without myelopathy) had cerebral indications (five had intracranial hemorrhage and one had a seizure). Cerebral angiography showed a posterior fossa DAVF with spinal venous drainage in all cases. The clinical presentation of DAVFs with spinal venous drainage was compared with the extent of the drainage. In patients without myelopathy, the spinal venous drainage exited the intradural canal via the cervical medullary-radicular veins and was therefore limited to the cervical perimedullary veins. In patients with myelopathy, no medullary-radicular vein was seen, and the venous drainage descended along the perimedullary veins of the entire spinal cord toward the conus medullaris. CONCLUSION: We found an exact relation between clinical presentation and venous drainage of DAVFs with spinal venous drainage. Patients had no myelopathy when the venous drainage was limited to the cervical cord; myelopathy was present when the venous drainage descended toward the conus medullaris.

Merkel cell carcinoma: a rare cause of hypervascular nasal tumor.

Cutaneous neuroendocrine carcinoma, first described in 1972, is an aggressive disease usually occurring in sun-exposed skin. Other sites have been described, however; such tumors occasionally occur within the nasal fossa. A high rate of metastasis (>30%) explains the poor prognosis. Descriptions of the imaging features of these tumors, mainly located in cutaneous region, are rare. We therefore present the imaging features of two cases of Merkel cell carcinoma involving the sinonasal region, suggestive of a hypervascular tumor.

Postoperative complications in otospongiosis: usefulness of MR imaging.

BACKGROUND AND PURPOSE: Sensorineural hearing loss (SNHL) is a rare complication of stapes surgery that may arise for many reasons. Usually, the pathogenesis of SNHL can be established by clinical and CT examinations. The purpose of this study was to evaluate the utility of MR imaging when CT findings are normal or not contributive. METHODS: Eleven patients with SNHL (in some instances, associated with vertigo) after stapedectomy, in whom CT showed no well-defined cause, were examined by MR imaging. RESULTS: MR studies established the additional findings of reparative intravestibular granuloma (n = 2), intralabyrinthine hemorrhage (n = 1), and bacterial labyrinthitis (n = 1). In five cases, MR findings were similar to CT findings. In two cases, CT and MR results were normal. Revision surgery was performed in five patients and confirmed the MR findings in each case. CONCLUSION: If CT is not contributive as to the origin of SNHL and vertigo occurring after stapes surgery, then MR imaging may be helpful in these patients.

Current status of musculoskeletal interventional radiology.

This article details many of the latest developments in the field of musculoskeletal interventional radiology. Some of the topics included in this discussion are percutaneous biopsy of musculoskeletal lesions, automated percutaneous discectomy, facet joint arthrography, percutaneous vertebroplasty, and percutaneous drainage of abscesses.

Papillary adenoma of endolymphatic sac origin: a temporal bone tumor in von Hippel-Lindau disease. Case report.

This report describes a patient with von Hippel-Lindau disease who presented with an 8-year history of a slow-growing, locally invasive vascularized lesion of the temporal bone involving the cerebellopontine angle. The mass, studied by computerized tomography scanning and magnetic resonance imaging techniques, was partly cystic in appearance. After removal of the mass, pathological studies confirmed a papillary cystic tumor with characteristics that have been described in tumors with an endolymphatic sac origin. These rare neoplasms constitute a distinct pathological entity and deserve wider recognition.

Magnetic resonance appearance of monoclonal gammopathies of unknown significance and multiple myeloma. The GRI Study Group.

STUDY DESIGN: A prospective multicenter study. OBJECTIVES: To evaluate the use of magnetic resonance imaging, in the differentiation between monoclonal gammopathies of unknown significance and multiple myeloma. SUMMARY OF BACKGROUND DATA: Although multiple myeloma has been studied extensively with magnetic resonance imaging, to the authors' knowledge, no study has evaluated the clinical interest of magnetic resonance imaging in the differentiation between monoclonal gammopathies of unknown significance and multiple myeloma. METHODS: The magnetic resonance examinations of the thoracolumbar spine in 24 patients with newly diagnosed monoclonal gammopathies of unknown significance were compared with those performed in 44 patients with newly diagnosed nontreated multiple myeloma. RESULTS: All findings on magnetic resonance examination performed in patients with monoclonal gammopathies of unknown significance were normal, whereas findings on 38 (86%) of the 44 magnetic resonance examinations performed in patients with multiple myeloma were abnormal. CONCLUSION: Magnetic resonance imaging can be considered as an additional diagnostic tool in differentiating between monoclonal gammopathies of unknown significance and multiple myeloma, which may be helpful when routine criteria are not sufficient. An abnormal finding on magnetic resonance examination in a patient with monoclonal gammopathies of unknown significance should suggest the diagnosis of multiple myeloma after other causes of marrow signal abnormalities are excluded. Magnetic resonance imaging also may be proposed in the long-term follow-up of monoclonal gammopathies of unknown significance when a new biologic or clinical event suggests the diagnosis of malignant monoclonal gammopathy.

[Puerperal thrombosis of the right ovarian vein. Clinical and radiological aspects apropos of a case]. / Thrombose puerpérale de la veine ovarienne droite compliquée d'embolies pulmonaires. Aspects cliniques et radiologiques a propos d'un cas.

The authors report the case of puerperal thrombosis of the right ovarian vein complicated by recurrent small pulmonary emboli in a 32 year old woman. The clinical features of this rare condition are reviewed. The echographic, angiographic and CT scan and magnetic resonance imaging abnormalities are described. The authors underline the value of non-invasive radiological investigations for early diagnosis. The patient was rapidly improved by medical therapy with antibiotics and heparin.

[Fibrolamellar carcinoma of the liver: hepatocellular carcinoma with favourable prognosis]. / Carcinome fibro-lamellaire du foie: un carcinome hépatocellulaire de pronostic favorable.

The authors report a case of fibrolamellar carcinoma of the liver in a young woman with bilateral lung metastases. This tumour was surgically unremovable. Presently, after a chemotherapy with adriamycin and mitomycin, this patient is in good health, two years after initial diagnosis. Review of the literature shows that fibrolamellar carcinoma of the liver occurs mainly in young patients. This tumor is characterised by large polygonal eosinophilic hepatocytes and an abundant fibrous stroma. It can be confused with focal nodular hyperplasia. Resection of the tumor and the methodical, repeated resections of metastases must be performed when possible. Prognosis of this tumor is better than that of the other variants of hepatocellular carcinoma.

[Budd-Chiari syndrome and membranous obstruction of the suprahepatic inferior vena cava. Treatment by percutaneous intraluminal angioplasty]. / Syndrome de Budd-Chiari et obstruction membraneuse de la veine cave inférieure sus-hépatique. Traitement par angioplastie intra-luminale percutanée.

A 38-year-old woman, suffering from a Budd-Chiari syndrome due to membranous obstruction of the inferior vena cava, has been treated by percutaneous trans-luminal angioplasty. The result is excellent six months after. The permeability of the vena cava has been studied by manometry and cavography. This innocuous procedure seems worth while in the treatment of Budd-Chiari syndrome with membranous obstruction of the inferior vena cava.

[A benign tumor of the cavum: Thornwald's cyst]. / Une tumeur bénigne du cavum: Le kyste de Thornwald.

The non neoplastic diseases of the nasopharynx are uncommon especially in adults. Cyst of pharyngeal bursa or Thornwald cyst are located in the supero-posterior nasopharynx, in the location of the normal pharyngeal bursa which open into the pharyngeal mucosa. When it persists, a cyst can develop if the orifice becomes occluded. The have a characteristic and distinctive C.T. and N.M.R. aspects, as presented in this paper, well circumscribed round midline mass, sparing muscles lateral as well as posterior, with an high signal in T1 and T2 N.M.R. sequences. No discussion with other pathologic conditions is useful because carcinoma, adenoid and pharyngeal polyp, or Killian's polyps haven't this configuration.