Role of magnetic resonance imaging in the detection and characterization of solid pancreatic nodules: an update

Pancreatic ductal adenocarcinoma is the most common malignant tumor of the pancreas. The remaining pancreatic tumors are a diverse group of pancreatic neoplasms that comprises cystic pancreatic neoplasms, endocrine tumors and other uncommon pancreatic tumors. Due to the excellent soft tissue contrast resolution, magnetic resonance imaging (MRI) is frequently able to readily separate cystic from noncystic tumors. Cystic tumors are often easy to diagnose with MRI; however, noncystic non-adenocarcinoma tumors may show a wide spectrum of imaging features, which can potentially mimic ductal adenocarcinoma. MRI is a reliable technique for the characterization of pancreatic lesions. The implementation of novel motion-resistant pulse sequences and respiratory gating techniques, as well as the recognized benefits of MR cholangiopancreatography, make MRI a very accurate examination for the evaluation of pancreatic masses. MRI has the distinctive ability of non-invasive assessment of the pancreatic ducts, pancreatic parenchyma, neighbouring soft tissues, and vascular network in one examination. MRI can identify different characteristics of various solid pancreatic lesions, potentially allowing the differentiation of adenocarcinoma from other benign and malignant entities. In this review we describe the MRI protocols and MRI characteristics of various solid pancreatic lesions. Recognition of these characteristics may establish the right diagnosis or at least narrow the differential diagnosis, thus avoiding unnecessary tests or procedures and permitting better management

Unenhanced whole-body MRI versus PET-CT for the detection of prostate cancer metastases after primary treatment

The aim of this study was to evaluate the accuracy of unenhanced whole-body MRI, including whole-body Diffusion Weighted Imaging (DWI), used as a diagnostic modality to detect  pathologic lymph nodes and skeletal metastases in patients with prostate cancer (PCa) undergoing restaging after primary treatment

Detection of crohn disease lesions of the small and large bowel in pediatric patients: diagnostic value of MR Enterography versus reference examinations

The purpose of this article is to prospectively determine the accuracy of MR enterography in detecting Crohn disease lesions from the jejunum to the anorectal region in pediatric patients, in comparison with main reference investigations. Fifty consecutive children with known Crohn disease underwent MR enterography with oral contrast agent and gadolinium-chelate intravenous injection. Two radiologists detected and localized lesions by dividing the bowel into nine segments (450 analyzed segments in 50 patients). Ileocolonoscopy, barium studies, intestinal ultrasound, and capsule endoscopy were considered as first- and second-level reference examinations and were performed within 15 days of MR enterography.MR enterography detected lesions in 164 of 450 segments, with 155 true-positive and nine false-positive findings; overall sensitivity, specificity, and positive and negative predictive values for small- and large-bowel lesions were 94.5%, 97%, 94.5%, and 97%, respectively (ĸ = 0.93; 95% CI, 0.89-0.97). Sensitivity and specificity values were 88% and 97%, respectively, for the jejunum, 100% and 97% for the proximal-to-mid ileum, 100% and 100% for the distal ileum, 93% and 100% for the cecum, 70% and 97% for the ascending colon, 80% and 100% for the transverse colon, 100% and 92% for the descending colon, 96% and 90% for the sigmoid colon, and 96% and 88% for the rectum. From jejunum to rectum, the AUC value ranged between 0.916 (jejunum) and 1.00 (distal ileum). Perianal fistulas were diagnosed in 15 patients, and other complications were found in 13 patients.MR enterography showed an accuracy comparable to that of reference investigations, for both small- and large-bowel lesions. Because MR enterography is safer and more comprehensive than the reference examinations, it should be considered the primary examination for detecting Crohn disease lesions in children

Magnetic resonance cholangiography: past, present and future: a review.

Introduction: Magnetic resonance cholangio-pancreatography (MRCP) is a valuable method for the evaluation of biliary and pancreatic diseases and a valuable alternative to endoscopic retrograde cholangiopancreatography (ERCP). It is noninvasive and does not require the use of contrast material or ionizing radiation. Since its introduction in 1991, this technique has significantly improved in spatial resolution, now allowing the accurate assessment of the major bilio-pancreatic diseases. State of the Art: MRCP is commonly performed with heavily T2-weighted sequences in order to highlight static fluids, as those contained in dilated pancreatic and biliary ducts. Newest MR equipments allow to perform MRCP within 10-15 minutes, due to the availability of ultra-fast sequences. Currently, MRCP is widely performed as a primary imaging modality for the assessment of obstructive jaundice and other benign or malignant bilio-pancreatic ducts abnormalities. The primary MRCP application is the evaluation of biliary obstructions due to choledocholithiasis, iatrogenic strictures, cholangiocarcinoma or pancreatic carcinoma. Other MRCP applications include the assessment of the exocrine pancreatic function, following secretin stimulation. Whenever needed, the MRCP may be completed with a conventional contrast-enhanced magnetic resonance imaging (MRI) of the upper abdomen and functional studies as well, thus providing an all-in-one mophological and functional study of the pancreas and biliary system. More recent applications include the possibility of 3D reconstructions and the use of hepato-biliary contrast agents, that provide a higher definition of the biliary tree, both in pathologic and normal conditions. The introduction of 3Tesla magnets could provide higher anatomic detail. Conclusions: In the next years the role of MRCP will further expand, due to the availability of faster sequences, 3D imaging and functional studies

Bilateral Adrenal Hemorrhage in a Patient with Myelodysplastic Syndrome: Value of MRI in the Differential Diagnosis

Bilateral adrenal hemorrhage is a rare potentially life-threatening event that occurs either in traumatic or nontraumatic conditions. The diagnosis is often complicated by its nonspecific presentation and its tendency to intervene in stressful critical illnesses. Due to many disorders in platelet function, hemorrhage is a major cause of morbidity and mortality in patients affected by myeloproliferative diseases. We report here the computed tomography and magnetic resonance imaging findings of a rare case of bilateral adrenal hemorrhage in a patient with myelodysplastic syndrome, emphasizing the importance of MRI in the differential diagnosis

Value of MRI of the hand and the wrist in evaluation of bone age: Preliminary results

Purpose To evaluate bone age determination using MRI of the hand and wrist. Materials and Methods A total of 179 (78 female and 101 males, 11 to 16 years old) subjects of 252 normal volunteers met entrance criteria. A low field open magnet (0.2 Tesla) was used for this study; coronal T1-weighted images with a slice thickness of 1.3 mm were acquired. Two blinded radiologists evaluated the studies and the following elements were considered: the appearance of cartilage, vacuolization of cartilage, provisional calcification, progression of ossification, and complete ossification. Correlation between chronologic age and MR bone age was determined by means of simple linear regression analysis. Results Strong correlation between MR skeletal age and chronological age was observed for both investigators, Pearson correlation R-2 = 0.9 for each. Conclusion Determination of bone age with MRI is feasible and shows good interobserver reproducibility. Data from this study may be useful to develop an atlas of skeletal development and bone age. J. Magn. Reson. Imaging 2014;39:1198-1205. (c) 2013 Wiley Periodicals, Inc

Differences in the location and activity of intestinal Crohn's disease lesions between adult and paediatric patients detected with MRI

To prospectively compare paediatric patients (PP) and adult patients (AP) affected by Crohn's disease (CD) in terms of the location and activity of intestinal lesions. Forty-three children (mean age 15 years) and 43 adults (mean age 48 years) with proven CD underwent magnetic resonance enterography (MRE) to localise lesions and detect their activity in 9 segments of the small and large bowel. The results were analysed on a per patient and per segment basis. Ileo-colonoscopy was performed in all patients. P values less than 0.05 were considered statistically significant. Involvement of terminal ileum was significantly different in the two groups: observed in 100 % of AP (43/43) versus 58 % (23/43) of PP (P < 0.0001). Conversely, the colon was diseased in 84 % of PP versus 64 % of AP. In particular, left colonic segments were significantly more involved in PP (descending colon 53 % versus 21 %, P < 0.01; rectum 67 % versus 23 %, P < 0.0001; sigmoid colon 56 % versus 37 %, not significant), whereas caecal involvement was equal in both groups. In children the maximal disease activity was found in left colonic segments, whereas in adults it was in the terminal ileum. MRE detected significant differences between the two populations, showing a more extensive and severe involvement of the left colon in children but the distal ileum in adults. aEuro cent MRI is useful for assessing Crohn's disease in adult and paediatric patients. aEuro cent Adult and paediatric patients show different intestinal involvement on MRI. aEuro cent The distal ileum is maximally involved in adults vs. the left colon in children. aEuro cent The causes of the severe left colonic disease in children are unknown. aEuro cent The extensive colonic involvement in children has clinical-diagnostic implications.OBJECTIVES: To prospectively compare paediatric patients (PP) and adult patients (AP) affected by Crohn's disease (CD) in terms of the location and activity of intestinal lesions