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The article reports on the importance of magnetic resonance imaging (MRI) in people with chronic liver disease. Topics discussed include the patients management, the liver cirrhosis diagnosis, and the treatment for liver cancer. Also mentioned are the health management, the hypervascular hepatocellular carcinoma (HCC) patients, and the liver diseases management.

Objectives: To assess the added value of diffusion-weighted imaging (DWI) to conventional magnetic resonance imaging (MRI) for differentiating benign from malignant bile duct strictures. Methods: Twenty-seven patients with a benign stricture and 42 patients with a malignant stricture who had undergone gadoxetic acid-enhanced MRI with DWI were enrolled. Qualitative (signal intensity, dynamic enhancement pattern) and quantitative (wall thickness and length) analyses were performed. Two observers independently reviewed a set of conventional MRI and a combined set of conventional MRI and DWI, and receiver operating characteristic (ROC) curve analysis was assessed. Results: Benign strictures showed isointensity (18.5-70.4 %) and a similar enhancement pattern (22.2 %) to that of normal bile duct more frequently than malignant strictures (0-40.5 % and 0 %) on conventional MRI ( P < 0.05). Malignant strictures (90.5-92.9 %) showed hypervascularity on arterial and portal venous phase images more frequently than benign strictures (37.0-70.4 %) ( P < 0.01) On DWI, all malignant strictures showed hyperintensity compared with benign cases (70.4 %) ( P < 0.001). Malignant strictures were significantly thicker and longer than benign strictures ( P < 0.001). The diagnostic performance of both observers improved significantly after additional review of DWI. Conclusions: Adding DWI to conventional MRI is more helpful for differentiating benign from malignant bile duct strictures than conventional MRI alone. Key points: • Accurate diagnosis and exclusion of benign strictures of bile duct are important. • Diffusion-weighted MRI helps to distinguish benign from malignant bile duct strictures. • DWI plus conventional MRI provides superior diagnostic accuracy to conventional MRI alone. [ABSTRACT FROM AUTHOR]

The article focuses on the techniques in predicting benign pancreatic neuroendocrine tumors (NETs). It is mentioned that the NETs have a wide variety of biological behavior, ranging from completely benign to highly aggressive tumors and abdominal magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) that may be useful for differentiating benign pancreatic NETs from non-benign pancreatic NETs.

Purpose: The purpose of this study is to evaluate the 'mushroom cap' sign on T2-weighted MR imaging in patients with submucosal tumors in the rectosigmoid colon. Methods: From January 2001 to August 2009, 12 patients with four different diseases presenting or mimicking submucosal tumors in the rectosigmoid colon underwent colonic resection. All patients with deep endometriosis ( n = 6), gastrointestinal stromal tumor ( n = 4), metastasis from ovary cancer ( n = 1), and carcinoid tumor ( n = 1) had either an MRI of the rectum or pelvis before surgery. We evaluated the MRI findings and compared them with the macroscopic and microscopic observations in the resected specimens. Results: In all six cases of deep endometriosis, a characteristic 'mushroom cap' shaped appearance was found on T2-weighted MR imaging. Heterogeneous low signal intensity of the hypertrophic muscularis propria, covered with high signal intensity of the mucosa and submucosa on T2-weighted MR images, looked like a 'mushroom cap' with the pattern of intraluminal endophytic growth. In histological findings, deep endometriosis involved the submucosa ( n = 4) or mucosa ( n = 2). The 'mushroom cap' sign was not present in any of the six other tumors. Conclusion: The 'mushroom cap' sign on T2-weighted MR imaging may be a characteristic sign for diagnosing deep rectosigmoid endometriosis. [ABSTRACT FROM AUTHOR]

Background: The aims of this study are to evaluate and compare the accuracies of isotropic multi-detector row CT (MDCT) including multiplanar reconstruction (MPR) images for preoperative staging of endoscopically diagnosed early gastric cancer (eEGC) and advanced gastric cancer (eAGC). Methods: One hundred and five patients with endoscopically proven gastric cancer underwent isotropic MDCT. Three independent radiologists evaluated T and N staging both on transverse images only and on three orthogonal MPR images. The staging of each tumor was surgico-pathologically confirmed. The receiver operating characteristic (ROC) analysis and the Wilcoxon signed ranked test were used for statistical analyses. Results: In 30 eAGCs, the accuracies for T and N staging with MPR imaging were better than those with transverse imaging (each P < 0.05). In 34 eEGCs, however, only the accuracy of T2 or higher with MPR imaging was higher than that with transverse imaging (P < 0.05). Conclusions: Isotropic MDCT with MPR images including coronal or sagittal reconstructions can improve the accuracies of preoperative T and N staging of eAGC, while having little impact on the accuracy for eEGC. [ABSTRACT FROM AUTHOR]

This study is a retrospective evaluation of the correlations between the presence and integrity of the capsule of nodular hepatocellular carcinomas (HCC) by dynamic CT and histopathology, with histopathologic evidence of tumor propagation to surrounding hepatic parenchyma. Dynamic CT scans of 75 nodular HCCs in 73 patients (61 men, 12 women; age range, 32-81; mean, 53) were evaluated regarding capsule visualization and integrity. Histopathologic findings of HCCs in resected specimens were correlated with the presence of a capsule, tumor invasion onto the capsule, and with the presence of microvascular emboli in the surrounding liver parenchyma. On histopathologic examination, capsules were present in 57 of 75 nodular HCCs; the capsules were invaded by tumor in 18 nodules and there were microvascular emboli around the nodular HCC in 49 cases. Capsule visualization by CT was correlated with the presence of capsule by histopathology (P<0.00). Disruption of capsule by CT was correlated with tumor invasion by histopathology (P=0.003) and with microvascular tumor emboli (P<0.00). The presence and structural integrity of HCC capsules on CT was closely correlated with the presence of capsule on histopathology and the absence of microvascular tumor emboli. [ABSTRACT FROM AUTHOR]

Objective To investigate the early imaging findings and growth rate of pancreatic ductal adenocarcinoma (PDAC), and to assess whether MR imaging detects early PDAC better than CT. Materials and methods The institutional review board approved this retrospective study and waived the requirement for informed consent. Twenty-two patients were included, and two radiologists, by consensus, assessed the presence of focal lesions, interruption of the main pancreatic duct (MPD), MPD dilatation, and pancreatitis, volume doubling time (VDT) of PDAC on prediagnostic MR imaging. Two other observers independently reviewed three image sets (CT images, unenhanced MR images, and unenhanced and contrast-enhanced MR images) for the detection of early PDAC. Paired Wilcoxon signed rank test and receiver operating characteristic (ROC) curve analysis were used for statistical analyses. Results In 20 (90.9%) patients, prediagnostic MR exams showed abnormality, and all of them showed focal lesions on the first abnormal prediagnostic MR exams. Thirteen lesions (65%) showed no MPD interruption and one lesion (5%) was accompanied by pancreatitis. The mean VDT of PDAC was 151.7 days (range, 18.3–417.8 days). Diagnostic performance of unenhanced MR images ( Az , 0.971–0.989) and combined unenhanced and contrast-enhanced MR images ( Az , 0.956–0.963) was significantly better than that of CT images ( Az , 0.565–0.583; p < 0.01) for both observers, Conclusion The most common early imaging finding of PDAC on prediagnostic MR exams was a focal lesion with no MPD interruption with a mean volume doubling time of five months. MR imaging was superior to CT for the detection of early PDAC. [ABSTRACT FROM AUTHOR]