Owing to the developments in imaging modalities, imaging has become an essential element in the early evaluation of and decision-making algorithm for patients with trauma. In particular, CT technology has developed over the past decades, resulting in faster image acquisition and higher image quality. Currently, CT is the key imaging modality for triaging surgical and non-surgical treatment in patients with abdominal trauma and plays an important role in increasing the frequency and success rate of non-surgical treatment. Because rapid and accurate diagnosis of injury in patients with trauma can improve the patients' prognosis, radiologists should be familiar with the imaging findings, especially the CT findings, in patients with trauma. In this article, the authors reviewed the considerations when performing CT for evaluating abdominal trauma. In addition, they described the important imaging findings and pitfalls when diagnosing blunt trauma in various intra-abdominal organs.

PURPOSE: To evaluate value of image subtraction for identifying hepatocellular carcinoma (HCC) capsule on gadoxetic acid-enhanced MR images. MATERIALS AND METHODS: This study involved 108 patients at risk of HCC preoperatively examined using gadoxetic acid-enhanced MRI with hepatic resection between May 2015 and February 2017. We evaluated qualities of subtraction images and presence of capsular appearance on portal venous or transitional phases conventional and subtraction images. We assessed effect of capsular appearance on subtraction images on HCC. RESULTS: After excluding 1 patient who had treated by transarterial chemoembolization prior to surgery and 33 patients with unsatisfactory subtraction image qualities, 82 focal hepatic lesions (73 HCC, 5 non-HCC malignancies, and 4 benign) from 74 patients were analyzed. Regarding detection of capsules, sensitivity, accuracy, and area under the receiver operating characteristic curve (AUC) on subtraction images were significantly higher than those on conventional images (95.4%, 89.0%, and 0.80, respectively; p < 0.001), though specificities were same (64.7%). For diagnosis of HCC, sensitivity, accuracy, and AUC on subtraction images were significantly higher than on conventional images (82.2%, 79.3%, and 0.69, respectively; p = 0.011), though specificities were identical (55.6%). CONCLUSION Portal venous or transitional phase gadoxetic acid-enhanced MRI subtraction images could improve detection of HCC capsule.

Objectives: Non-alcoholic fatty liver disease (NAFLD) is an increasingly prevalent metabolic disease. Muscle is known to influence NAFLD development. Therefore, this study aimed to determine the relationships among low muscle mass, NAFLD, and hepatic fibrosis using various definitions of low muscle mass and NAFLD diagnostic methods, including magnetic resonance imaging-based proton density fat fraction (MRI-PDFF). Methods: This cross-sectional study included 320 participants (107 males, 213 females) from the Korean Genome and Epidemiology Study on Atherosclerosis Risk of Rural Areas in the Korean General Population cohort. Muscle mass was assessed using whole-body dual-energy X-ray absorptiometry and adjusted for the height squared, body weight, and body mass index (BMI). NAFLD was diagnosed using ultrasonography (US), MRI-PDFF, and the comprehensive NAFLD score (CNS). Hepatic fibrosis was assessed using magnetic resonance elastography. Multivariable logistic and linear regression analyses were performed to determine the aforementioned associations. Results: According to US, 183 participants (57.2%) had NAFLD. Muscle mass adjusted for body weight was associated with NAFLD diagnosed using US (odds ratio [OR], 3.00; 95% confidence interval [CI], 1.70 to 5.31), MRI-PDFF (OR, 2.00; 95% CI, 1.13 to 3.53), and CNS (OR, 3.39; 95% CI, 1.73 to 6.65) and hepatic fibrosis (males: β=-0.070, p<0.01; females: β=-0.037, p<0.04). Muscle mass adjusted for BMI was associated with NAFLD diagnosed by US (OR, 1.71; 95% CI, 1.02 to 2.86) and CNS (OR, 1.95; 95% CI, 1.04 to 3.65), whereas muscle mass adjusted for height was not associated with NAFLD. Conclusions Low muscle mass was associated with NAFLD and liver fibrosis; therefore, maintaining sufficient muscle mass is important to prevent NAFLD. A prospective study and additional consideration of muscle quality are needed to strengthen the findings regarding this association.

OBJECTIVE: To validate the diffusion-weighted MRI (DWI) for differentiation of benign from malignant portal vein thrombosis. MATERIALS AND METHODS: The Institutional Review Board approved this retrospective study and waived informed consent. A total of 59 consecutive patients (52 men and 7 women, aged 40-85 years) with grossly defined portal vein thrombus (PVT) on hepatic MRI were retrospectively analyzed. Among them, liver cirrhosis was found in 45 patients, and hepatocellular carcinoma in 47 patients. DWI was performed using b values of 50 and 800 sec/mm2 at 1.5-T unit. A thrombus was considered malignant if it enhanced on dynamic CT or MRI; otherwise, it was considered bland. There were 18 bland thrombi and 49 malignant thrombi in 59 patients, including 8 patients with simultaneous benign and malignant PVT. Mean apparent diffusion coefficients (ADCs) of benign and malignant PVTs were compared by using Mann-Whitney U test. Diagnostic accuracy was evaluated using receiver operating characteristic (ROC) curve analysis. RESULTS: The mean ADC ± standard deviation of bland and malignant PVT were 1.00 ± 0.39 × 10(-3) mm2/sec and 0.92 ± 0.25 × 10(-3) mm2/sec, respectively; without significant difference (p = 0.799). The area under ROC curve for ADC was 0.520. An ADC value of > 1.35 × 10(-3) mm2/sec predicted bland PVT with a specificity of 94.6% (95% confidence interval [CI]: 84.9-98.9%) and a sensitivity of 22.2% (95% CI: 6.4-47.6%), respectively. CONCLUSION: Due to the wide range and considerable overlap of the ADCs, DWI cannot differentiate the benign from malignant thrombi efficiently.
Carcinoma, Hepatocellular ; Diagnosis ; Diffusion ; Diffusion Magnetic Resonance Imaging ; Ethics Committees, Research ; Female ; Humans ; Informed Consent ; Liver Cirrhosis ; Magnetic Resonance Imaging* ; Male ; Portal Vein* ; Retrospective Studies ; ROC Curve ; Sensitivity and Specificity ; Thrombosis ; Venous Thrombosis*

Inflammatory pseudotumor of the liver is a benign disease which is histologically characterized by plasma cell infiltration and reactive fibrotic inflammation. Differentiating this disease from malignant tumor is not easy. The authors report a case of inflammatory pseudotumor mimicked as intrahepatic cholangiocarcinoma. A 74-year-old man visited the emergency department complaining of jaundice and myalgia which have lasted for 1 to 2 weeks. After computed tomography (CT) scan and magnetic resonance imaging of the liver, he was initially diagnosed with intrahepatic cholangiocarcinoma, but was ultimately found to be inflammatory pseudotumor after pathologic examination of the liver tissue. His symptoms improved after a course of antibiotic therapy and conservative treatment, and the lesion disappeared on follow-up CT scan.
Aged ; Cholangiocarcinoma* ; Emergency Service, Hospital ; Follow-Up Studies ; Granuloma, Plasma Cell* ; Humans ; Inflammation ; Jaundice ; Liver* ; Magnetic Resonance Imaging ; Myalgia ; Plasma Cells ; Tomography, X-Ray Computed

PURPOSE: To investigate the clinical significance of gallbladder (GB) wall thickening frequently observed in patients with acute hepatitis A. METHODS: A total of 328 consecutive patients who were diagnosed with acute hepatitis A and underwent abdominal ultrasonography were enrolled retrospectively. Patients were divided into two groups: GB wall thickening (> or =3 mm, group A) and no thickening (group B). Group A was subdivided into two subgroups (GB wall thickening of > or =10 mm, group A-1 and > or =3 mm to <10 mm, group A-2). The laboratory results related to liver function, hospitalization duration, and time to normalization of liver function were compared between the groups. RESULTS: A total of 230 patients showed GB wall thickening (group A). Besides gamma-glutamyl transpeptidase and alkaline phosphatase, all laboratory results of group A were significantly higher than those of group B (P<0.05). Compared with group B, the hospitalization duration and the time to normalization of liver function were significantly longer in group A (P<0.05). Group A-1 included 146 patients and group A-2 included 84 patients. No significant differences in laboratory results, hospitalization duration, and time to normalization of liver function were found between the two subgroups. In the multivariate logistic regression analysis, serum alanine transaminase, total bilirubin and albumin levels, and hospitalization duration were significantly associated with GB wall thickening in patients with hepatitis A. CONCLUSION: The presence of GB wall thickening in patients with acute hepatitis A suggests a poorer prognosis irrespective of the degree of GB wall thickening or the degree of liver enzyme elevation.
Alanine Transaminase ; Alkaline Phosphatase ; Bilirubin ; Gallbladder* ; gamma-Glutamyltransferase ; Hepatitis A* ; Hospitalization ; Humans ; Liver ; Liver Function Tests ; Logistic Models ; Prognosis ; Retrospective Studies ; Ultrasonography