Benign Brenner tumour of the ovary: CT and MRI features.

AIM: To evaluate the computed tomography (CT) and magnetic resonance imaging (MRI) features of benign Brenner tumours (BBT) of the ovary. MATERIAL AND METHODS: This was a retrospective two-centre study comprising 35 female patients with a definitive diagnosis of BBT at histology in whom CT and/or MRI examinations had been performed. Two experienced radiologists reviewed the CT and MRI features of 39 ovarian BBT retrospectively with consensus reading. The morphological appearance and size of each tumour were recorded. The presence or absence of calcifications within the solid portion was noted at CT. The reviewed characteristics at MRI included qualitative assessment of the signal intensity of the solid portion on diffusion sequence and contrast enhancement, compared to that of the myometrium. RESULTS: CT and MRI images were available for 27 and 28 lesions, respectively. Sixteen patients had both CT and MRI examinations. BBT were unilateral in 89% of patients, and 49% of lesions were solid and 51% were mixed. Calcifications were depicted at CT in 70.4% of lesions. When present, the cystic portion was multilocular in 85% of cases and corresponded to a mucinous lesion in 74% of cases. Enhancement of the solid portion at MRI was inferior or equal to that of the myometrium in 89% of cases and signal on high b-values diffusion images was deemed low or moderate in 93% of cases. CONCLUSION: The combined CT and MRI findings of a unilateral fibrous ovarian mass containing punctate calcifications often associated with a multilocular cyst suggest the diagnosis of ovarian BBT.

Multiparametric magnetic resonance imaging of parotid tumors: A systematic review.

PURPOSE: The purpose of this systematic review was to provide an overview of the contribution of multiparametric magnetic resonance imaging (MRI) in the diagnosis of parotid tumors (PT) and recommendations based on current evidences. MATERIAL AND METHODS: We performed a retrospective systematic search of PubMed, EMBASE, and Cochrane Library databases from inception to January 2020, using the keywords "magnetic resonance imaging" and "salivary gland neoplasms". RESULTS: The initial search returned 2345 references and 90 were deemed relevant for this study. A total of 54 studies (60%) reported the use of diffusion-weighted imaging (DWI) and 28 studies (31%) the use of dynamic contrast-enhanced (DCE) imaging. Specific morphologic signs of frequent benign PT and suggestive signs of malignancy on conventional sequences were reported in 37 studies (41%). DWI showed significant differences in apparent diffusion coefficient (ADC) values between benign and malignant PT, and especially between pleomorphic adenomas and malignant PT, with cut-off ADC values between 1.267×10-3mm2/s and 1.60×10-3mm2/s. Perfusion curves obtained with DCE imaging allowed differentiating among pleomorphic adenomas, Warthin's tumors, malignant PT and cystic lesions. The combination of morphological MRI sequences, DCE imaging and DWI helped increase the diagnostic accuracy of MRI. CONCLUSION: Multiparametric MRI, including morphological MRI sequences, DWI and DCE imaging, is the imaging modality of choice for the characterization of focal PT and provides features that are highly suggestive of a specific diagnosis.

Fat-containing lesions of the liver: a pictorial essay.

The presence of fat within a hepatic lesion is unusual and can help to direct the radiologist's diagnosis. The aim of this iconographic review is to specify the various hepatic lesions that may contain fat and their appearance particularly on MRI. A histological correlation is also suggested for the most commonly found tumors. The identification of fat within a hepatic tumor, along with other radiological signs and reflection on the clinical and epidemiological context, can lead to a diagnosis being reached or suggested, with confirmation if necessary, by a pathological examination.

CT imaging of peritoneal carcinomatosis and its mimics.

Invasive peritoneal disease includes more than just peritoneal carcinomatosis. Although this is the most common aetiology, especially when a primary is found, other conditions may be responsible for peritoneal invasion. A rigorous analysis of CT features taken together with the clinical and biological context usually allows the main differential diagnoses, which entail different types of management, to be drawn out. Pseudomyxoma peritonei, peritoneal lymphomatosis, tuberculosis, peritoneal mesothelioma, diffuse peritoneal leiomyomatosis, and benign splenosis are the main differential diagnoses.

Diffusion-weighted magnetic resonance imaging in ileocolonic Crohn's disease: validation of quantitative index of activity.

OBJECTIVES: Magnetic resonance imaging (MRI) allows accurate assessment of Crohn's disease (CD), but requires gadolinium injection. Diffusion-weighted (DW)-MRI yields comparable performances in small bowel CD. We compared the accuracy of DW-MR enterocolonography (MREC) and the magnetic resonance index of activity (MaRIA), and performed an external validation of the Clermont score in assessing inflammation in CD. METHODS: This was an observational prospective study of a single-center cohort. A total of 130 CD patients underwent consecutively MREC with gadolinium injection and DWI sequences between July 2011 and December 2012. RESULTS: Of the 848 evaluated segments (small bowel=352, colon/rectum=496), 175 (20.6%) were active (small bowel=111, colon/rectum=64) defined as MaRIA ≥7. Using a receiver operating characteristic (ROC) curve, we determined an apparent coefficient of diffusion (ADC) threshold of 1.9 × 10(-3) mm(2)/s that yielded a sensitivity and a specificity in discriminating active from nonactive CD of 96.9% and 98.1%, respectively, for the colon/rectum, and 85.9% and 81.6%, respectively, for the ileum. ADC was better correlated to MaRIA ≥7 than related contrast enhancement obtained with injected sequences (P<0.001). The Clermont score (=1.646 × bowel thickness-1.321 × ADC+5.613 × edema+8.306 × ulceration+5.039) was highly correlated with the MaRIA (rho=0.99) in ileal CD but not in colonic CD (rho <0.80). Interobserver agreement was high with regard to ADC measurement (correlation >0.9, P<0.001, and concordance >0.9, P<0001). CONCLUSIONS: DW-MREC is a reliable tool to assess inflammation in colonic (ADC) and ileal (Clermont score) CD and its use in daily practice would avoid gadolinium injection.

Fibrous tumours of the ovary: aetiologies and MRI features.

The ovaries can be affected by a vast variety of tumours, which may be benign or malignant, solid or cystic. Although ultrasonography is often the first examination performed in the evaluation of gynaecological conditions, magnetic resonance imaging is nowadays the most accurate imaging technique in the characterization of ovarian masses. Once the ovarian origin of a pelvic mass has been determined, the detection of any fibrous component within the lesion significantly reduces the spectrum of aetiologies that should be considered. Fibrotic tissue usually displays marked low-signal intensity on T2-weighted sequences at MRI, and enhancement is mostly moderate after intravenous administration of gadolinium chelates. This review aims to provide the main diagnoses to consider at MRI whenever an ovarian tumour, both purely solid or solid and cystic, contains a fibrous component, even if minimally abundant. The corresponding key imaging features are provided.

Hepatic haemangioma: common and uncommon imaging features.

The haemangioma, the most common non-cystic hepatic lesion, most often discovered by chance, may in certain situations raise diagnostic problems in imaging. In this article, the authors first demonstrate that the radiological appearance of the hepatic haemangioma, in its typical form, is closely related to three known histological sub-types. They then show that certain atypical features should be known in order to establish a diagnosis. They also observe the potential interactions between the haemangioma, an active vascular lesion, and the adjacent hepatic parenchyma. Finally, they discuss the specific paediatric features of hepatic haemangiomas and illustrate the case of a hepatic angiosarcoma.

[Lymphoma and arteries: peri- or intravascular?]. / Lymphome et artères: une atteinte périvasculaire ou intravasculaire?

PURPOSE: Lymphoma is a polymorphous disease that does not spare arteries. Arterial involvement may be perivascular or intravascular, with different prognostic and therapeutic implications. PATIENTS AND METHODS: We present here one case of perivascular lymphoma and another case of intravascular lymphoma in order to highlight the specific features of each type. RESULTS: The first patient was a woman who presented a pseudo-aneurysmal anterior iliac artery due to a non-Hodgkin lymphoma with subsequent bilateral pyelocalyceal distension. The second patient was a man who developed intravascular lymphomatosis expressed by an aneurysm of the common femoral then the primitive iliac artery. CONCLUSION: The distinction between perivascular and intravascular arterial involvement is based on a range of features and is essential for an optimal care of patients with lymphoma.

Advantages of gadobenate dimeglumine-enhanced MR cholangiography in the diagnosis of post-liver transplant bile leakage.

OBJECTIVE: To assess the value of magnetic resonance cholangiography with gadobenate dimeglumine (Gd-BOPTA) where there is a suspicion of bile leakage in the post-liver transplant patient. PATIENTS AND METHODS: Eight patients who had undergone a liver transplant underwent 14 MR cholangiograms, five of whom presented bile leakage while the other three had no biliary system complications. The results were compared to conventional bile duct opacification (by endoscopy or t-tube cholangiogram). The analysis covered whether there was opacification of the common bile duct and intrahepatic bile ducts on T1-weighted sequences after an injection of Gd-BOPTA on delayed biliary excretion phase sequences that were carried out on average 74 min after the injection. Enhancing perihepatic collections were also taken into account. RESULTS: Opacification of the bile ducts on delayed-phase MR cholangiogram sequences was always seen in the absence of bile leakage, and was never found when leakage was present. Enhancing perihepatic collections pointed to bile leakage every time. CONCLUSION: Gd-BOPTA-enhanced MR cholangiography is a simple and non-invasive technique for detecting bile leakage in the post-liver transplant patient.

Diffusion-weighted magnetic resonance imaging for detecting and assessing ileal inflammation in Crohn's disease.

BACKGROUND: Whether diffusion-weighted imaging (DWI)-MRI is of value in detecting and assessing inflammation of ileal Crohn's disease (CD) remains poorly investigated. AIM: To compare DWI-MR enterography (MRE) with conventional MRE in estimating inflammation in small bowel CD, to determine an apparent diffusion coefficient (ADC) threshold to differentiate active from non-active lesions and to assess inter-observer agreement. METHODS: Thirty-one CD patients from the Clermont-Ferrand IBD unit with ileal involvement were consecutively and prospectively included between April and June 2011. All patients underwent DWI-MRI to detect the digestive segment with the most severe lesions, which was then used to calculate the ADC. Qualitative and quantitative results were compared with conventional MRE including MaRIA (Magnetic Resonance Index of Activity) score calculation and independent activity predictors (wall thickening, oedema, ulcers). Each examination was interpreted independently by two radiologists blinded for clinical assessment. RESULTS: Seventeen patients (54.8%) had active CD as defined by the MaRIA score ≥7. DWI hyperintensity was highly correlated with disease activity evaluated using conventional MRE (P = 0.001). Qualitative analysis of DW sequences determined sensitivity, specificity, positive predictive value and negative predictive value as 100%, 92.9%, 94.4% and 100% respectively. Quantitative analysis using a cut-off of 1.6 × 10(-3) mm(2)/s for ADC yielded sensitivity and specificity values of, respectively, 82.4% and 100%. Inter-observer agreement was high with regard to DWI hyperintensity (κ = 0.69, accuracy rate = 85.7%) and ADC (correlation = 0.74, P < 0.001, and concordance = 0.71, P < 0.001). CONCLUSION: DWI-MR enterography is a well-tolerated, non-time-consuming and accurate tool for detecting and assessing inflammation in small bowel Crohn's disease.

Abdominal complications following neutropenia and haematopoietic stem cell transplantation: CT findings.

In haematology units, acute abdominal symptoms are common and often challenging for the clinician in charge. Two haematological conditions that may induce specific diagnoses are of particular concern: neutropenia and haematopoietic stem cell transplantation. Clinical and biological manifestations, including abdominal pain, fever, diarrhoea, hepatic cytolysis, or cholestasis are often non-specific. Computed tomography is often the primary imaging screening technique performed in such patients, as it is widely available, performs well for this indication, and may demonstrate evocative findings. The aim of this review is to provide the spectrum of specific diagnoses encountered and the corresponding key CT features in patients presenting with acute abdominal disorders following neutropenia and/or haematopoietic stem cell transplantation.

Two more cases of evaluation of POEMS syndrome using 18-FDG PET/CT.

Following the article of Alberti et al., we would like to provide our own experience with two more cases in evaluation of POEMS syndrome using morphological and functional imaging modalities, including plain X-rays, computed tomography (CT), magnetic resonance imaging (MRI), bone scintigraphy and positrons emission tomography with computed tomography (PET/CT). Among them, 18-FDG PET/CT proved its usefulness allowing extensive screening of the bony lesions involved.