A Comparative Study of Survivor Outcomes between Preoperative Evaluation Using CT Alone and Combined CT and MRI in Patients with Pancreatic Ductal Adenocarcinoma.

Purpose: To compare the recurrence pattern, disease-free survival (DFS), and overall survival (OS) after curative surgery for pancreatic ductal adenocarcinoma (PDAC) in patients who underwent preoperative evaluation with CT alone or in combination with MRI, and to compare the prognosis according to the first recurrence site.

Materials And Methods: We retrospectively evaluated 152 patients who underwent R0 resection of PDAC. Preoperative CT or combined CT and MRI were performed for 103 and 49 patients, respectively.

Differentiation of hypervascular primary hepatic tumors showing hepatobiliary hypointensity on gadoxetic acid-enhanced magnetic resonance imaging.

Purpose: To determine the imaging features that help differentiate hypervascular primary hepatic tumors showing hepatobiliary hypointensity on gadoxetic acid MRI.

Methods: This study comprised 148 patients with pathologically proven hypervascular hepatic tumors who underwent gadoxetic acid MRI. Tumors included 23 atypical focal nodular hyperplasias (FNHs), 11 hepatocellular adenomas (HCAs), 15 neuroendocrine tumors (NETs), 25 intrahepatic cholangiocarcinomas (ICCs), and 74 hepatocellular carcinomas (HCCs).

Diagnosis of recurrent HCC: intraindividual comparison of gadoxetic acid MRI and extracellular contrast-enhanced MRI.

Purpose: To compare the efficacy of magnetic resonance imaging (MRI) with hepatobiliary agents (HBA-MRI) and MRI with extracellular contrast agents (ECA-MRI) for detection of recurrent hepatocellular carcinoma (HCC) after multiple treatments.

Methods: The institutional review board approved this retrospective study and waived the requirement for informed patient consent. A total of 135 patients with suspected HCC recurrence after 2-5 treatments (surgery, transarterial chemoembolization, and/or radiofrequency ablation) underwent both HBA-MRI and ECA-MRI within a 1 month interval.

Intrahepatic Mass-forming Cholangiocarcinoma: Arterial Enhancement Patterns at MRI and Prognosis.

Purpose To identify whether arterial enhancement pattern at MRI could predict the prognosis after surgical resection of intrahepatic mass-forming cholangiocarcinoma (IMCC). Materials and Methods Patients who underwent curative hepatic resection and preoperative MRI for IMCC from November 2007 to September 2016 were retrospectively evaluated. MRI enhancement pattern was classified by two radiologists.

Usefulness of noncontrast MRI in differentiation between gallbladder carcinoma and benign conditions manifesting as focal mild wall thickening.

Background: Magnetic resonance imaging (MRI) is a reliable imaging tool for evaluating gallbladder carcinoma, but it is costly and time-consuming.

Purpose: To compare noncontrast MRI with multidetector row CT (MDCT) and gadoxetic acid-enhanced whole MRI in distinguishing gallbladder carcinoma from benign disease.

Materials And Methods: 101 patients (36 with gallbladder carcinoma and 65 with benign disease) with mild focal gallbladder wall thickening were included.

Differentiation between inflammatory myofibroblastic tumor and cholangiocarcinoma manifesting as target appearance on gadoxetic acid-enhanced MRI.

Purpose: To determine the differential features of inflammatory myofibroblastic tumor (IMT) and intrahepatic cholangiocarcinoma (ICC) manifesting as target appearance on gadoxetic acid-enhanced MRI.

Methods: Twenty-seven patients with 36 IMTs (1.2-6.

Intra-individual comparison of gadolinium-enhanced MRI using pseudo-golden-angle radial acquisition with gadoxetic acid-enhanced MRI for diagnosis of HCCs using LI-RADS.

Objectives: To determine the usefulness of extracellular contrast agent (ECA)-enhanced multiphasic liver magnetic resonance imaging (MRI) using a pseudo-golden-angle radial acquisition scheme by intra-individual comparison with gadoxetic acid-MRI (EOB-MRI) with regard to image quality and the diagnosis of hepatocellular carcinoma (HCC).

Materials And Methods: This prospective study enrolled 15 patients with 18 HCCs who underwent EOB-MRI using a Cartesian approach and ECA-MRI using the pseudo-golden-angle radial acquisition scheme (free-breathing continuous data acquisition for 64 s following ECA injection, generating six images). Two reviewers evaluated the arterial and portal phases of each MRI for artifacts, organ sharpness, and conspicuity of intrahepatic vessels and the hepatic tumors.

Prospective Intraindividual Comparison of Magnetic Resonance Imaging With Gadoxetic Acid and Extracellular Contrast for Diagnosis of Hepatocellular Carcinomas Using the Liver Imaging Reporting and Data System.

We intraindividually compared the efficacy of magnetic resonance imaging (MRI) with extracellular contrast agents (ECA-MRI) and MRI with hepatobiliary agents (HBA-MRI) for the diagnosis of hepatocellular carcinoma (HCC) using the Liver Imaging Reporting and Data System (LI-RADS). Between November 2016 and November 2017, we enrolled 91 patients with chronic liver disease who underwent both ECA-MRI and HBA-MRI within a 1-month interval for a first detected hepatic nodule on ultrasound. In total, 117 observations (95 HCCs, 19 benign lesions, and 3 other malignancies; median size, 18 mm) were identified with surgical resection.

Guidelines for the Diagnosis and Treatment of Chronic Functional Constipation in Korea, 2015 Revised Edition.

The Korean Society of Neurogastroenterology and Motility first published guidelines for chronic constipation in 2005 and was updated in 2011. Although the guidelines were updated using evidence-based process, they lacked multidisciplinary participation and did not include a diagnostic approach for chronic constipation. This article includes guidelines for diagnosis and treatment of chronic constipation to realistically fit the situation in Korea and to be applicable to clinical practice.

Missed pancreatic ductal adenocarcinoma: Assessment of early imaging findings on prediagnostic magnetic resonance imaging.

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.

Diagnostic accuracy and prognostic impact of restaging by magnetic resonance imaging after preoperative chemoradiotherapy in patients with rectal cancer.

Background: The prognostic role of restaging rectal magnetic resonance imaging (MRI) in patients with preoperative CRT has not been established. The goal of this study was to evaluate the diagnostic accuracy and prognostic role of radiological staging by rectal MRI after preoperative chemoradiation (CRT) in patients with rectal cancer.

Methods: A total of 231 consecutive patients with rectal cancer who underwent preoperative CRT and radical resection from January 2008 to December 2009 were prospectively enrolled.

Is colonoscopy necessary after computed tomography diagnosis of acute diverticulitis?

Background/aims: A diagnosis of acute diverticulitis is based on computed tomography (CT). Colonoscopy is commonly performed after the acute event to exclude other diagnoses. This study aimed to determine whether colonoscopy is necessary and what additional information is gained from a colonoscopy after acute diverticulitis.

Value of diffusion-weighted MRI for differentiating malignant from benign intraductal papillary mucinous neoplasms of the pancreas.

Objective: The purpose of this study was to evaluate whether the use of diffusion-weighted MRI (DWI) increases diagnostic accuracy in the differentiation of malignant from benign intraductal papillary mucinous neoplasms (IPMNs) of the pancreas over the accuracy of contrast-enhanced MRI with MRCP.

Materials And Methods: A total of 61 patients with surgically resected IPMNs (19 malignant, 42 benign) who underwent gadoxetic acid-enhanced MRI, DWI, and MRCP were included. Two blinded observers evaluated two image sets, that is, conventional MRI with MRCP images versus combined conventional MRI with MRCP and DW images, and scored their confidence for malignancy of IPMNs.

Differentiation of malignant from benign focal splenic lesions: added value of diffusion-weighted MRI.

Objective: The objective of our study was to evaluate the added value of diffusion-weighted imaging (DWI) for distinguishing between malignant and benign focal splenic lesions.

Materials And Methods: This study included 53 patients with 11 malignant and 42 benign splenic lesions who underwent gadoxetic acid-enhanced MRI and DWI. Qualitative and quantitative analyses were conducted for splenic lesions.

The role of diffusion-weighted MR imaging for differentiating benign from malignant bile duct strictures.

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.

The value of gadoxetic acid-enhanced and diffusion-weighted MRI for prediction of grading of pancreatic neuroendocrine tumors.

Background: Parenchyma-preserving resection for the treatment of benign pancreatic neuroendocrine tumors (NETs) has been tried, and preoperative prediction of benign pancreatic NET is important. Recently, diffusion-weighted imaging (DWI) of abdomen magnetic resonance imaging (MRI) has been used to characterize benign and malignant tumors and DWI might be helpful in prediction of benign pancreatic NETs.

Purpose: To evaluate the value of gadoxetic acid-enhanced MRI and DWI in predicting benign pancreatic NETs for determination of parenchyma-preserving resection.

Ectopic pancreas in upper gastrointestinal tract: MRI findings with emphasis on differentiation from submucosal tumor.

Background: Ectopic pancreas can frequently be mistaken for other submucosal masses. Ectopic pancreas may follow the signal intensity of mother pancreas on various magnetic resonance (MR) sequences, which might be helpful for differentiation between ectopic pancreas and other submucosal tumors in upper gastrointestinal (UGI) tract.

Purpose: To evaluate the value of MR imaging (MRI) in differentiating ectopic pancreases from submucosal tumors in UGI tract.

Differentiating hepatic abscess from malignant mimickers: value of diffusion-weighted imaging with an emphasis on the periphery of the lesion.

Purpose: To evaluate the efficacy of diffusion-weighted imaging (DWI) in differentiating hepatic abscess from malignant mimickers with an emphasis on periphery of the lesions.

Materials And Methods: Thirty-nine patients with hepatic abscess and 74 patients with malignant hepatic tumors were included, who underwent gadoxetic acid-enhanced MRI. For qualitative and quantitative analysis, signal intensities and apparent diffusion coefficient (ADC) values of the periphery were assessed.

CT detection of dry peritoneal seeding in patients with advanced gastric cancer.

Background/aims: To determine the significant CT findings of dry peritoneal seeding (DPS) in patients with advanced gastric cancer (AGC) and to assess whether radiologists' performance in the detection of DPS can be improved using these significant CT findings.

Methodology: Two radiologists reviewed CT images of AGC patients with DPS and without seeding for the presence or absence of various CT findings suggesting peritoneal seeding, in consensus. Significant CT findings for DPS were determined using Fisher's exact test.

Should preoperative chest CT be recommended to all colon cancer patients?

Objective: The aim of this study was to evaluate the efficacy of preoperative chest computed tomography (CT) and the risk factors for lung metastasis in colon cancer patients without liver metastasis who had negative findings on initial chest X-ray (CXR).

Background: Preoperative staging with chest CT is recommended in colon cancer patients. However, there have been only scant data on the clinical efficacy.

Added value of diffusion-weighted MR imaging in the diagnosis of ampullary carcinoma.

Purpose: To evaluate the added value of diffusion-weighted magnetic resonance (MR) imaging in diagnostic performance of conventional MR imaging for diagnosis of ampullary carcinoma.

Materials And Methods: This retrospective study was institutional review board approved, and informed consent was waived. Twenty-three patients with malignant ampullary obstruction and 39 patients with benign ampullary obstruction were included.

Differentiation of an intrapancreatic accessory spleen from a small (<3-cm) solid pancreatic tumor: value of diffusion-weighted MR imaging.

Purpose: To evaluate the value of diffusion-weighted (DW) imaging in differentiation of an intrapancreatic accessory spleen (IPAS) from a small (<3 cm) solid pancreatic tumor.

Materials And Methods: This retrospective study was approved by the institutional review board, and informed consent was waived. Twenty patients with IPAS and 22 patients with small solid pancreatic tumors were included.

High-risk esophageal varices in patients treated with locoregional therapy for hepatocellular carcinoma: assessment with liver computed tomography.

Aim: To assess the diagnostic performance of follow-up liver computed tomography (CT) for the detection of high-risk esophageal varices in patients treated with locoregional therapy for hepatocellular carcinoma (HCC).

Methods: We prospectively enrolled 100 patients with cirrhosis who underwent transcatheter arterial chemoembolization, radiofrequency ablation or both procedures for HCCs. All patients underwent upper endoscopy and subsequently liver CT.

Small submucosal tumors of the stomach: differentiation of gastric schwannoma from gastrointestinal stromal tumor with CT.

Objective: To identify the CT features that help differentiate gastric schwannomas (GS) from small (5 cm or smaller) gastrointestinal stromal tumors (GIST) and to assess the growth rates of both tumors.

Materials And Methods: We included 16 small GSs and 56 GISTs located in the stomach. We evaluated the CT features including size, contour, surface pattern, margins, growth pattern, pattern and degree of contrast enhancement, and the presence of intralesional low attenuation area, hemorrhage, calcification, surface dimpling, fistula, perilesional lymph nodes (LNs), invasion to other organs, metastasis, ascites, and peritoneal seeding.