Hyeong Cheol Shin

Traumatic bowel perforation Analysis of CT findings according to the perforation site and the elapsed time since accident

Abdominal CTs of 57 patients with bowel perforation after blunt abdominal trauma were retrospectively analyzed to determine: the diagnostic accuracy of the perforation site, and the differential findings according to the elapsed time from the trauma. Diagnostic accuracy of the perforation site was as follows: duodenum (100%), jejunum (81%), jejunoileal junction (100%), ileum (93%), and colon (20%). Extraluminal air was the only significant differential findings according to the elapsed time, and was seen more commonly on late stage of bowel perforation (P<.05).

Color Doppler Twinkling Artifacts in Various Conditions During Abdominal and Pelvic Sonography

Objective. The aims of this study were to describe the mechanisms likely to be responsible for color Doppler twinkling artifacts and their associated machine factors and to illustrate the various conditions that cause twinkling artifacts and those pitfalls. Methods. We evaluated various sonographic machine‐associated factors that influence artifact appearance and identified various conditions that display twinkling artifacts during abdominal and pelvic sonography. Results. The presence of twinkling artifacts was found to be dependent on focal zones, gray scale gains, color write priorities, and pulse repetition frequencies. Twinkling artifacts were found to be associated with calcified lesions in the liver, gallbladder adenomyomatosis, hepatic bile duct hamartoma, gallstones and choledocholithiasis, chronic pancreatitis, urinary stones, encrusted indwelling urinary stents, bowel gas, and metallic foreign bodies. However, some of the twinkling artifacts were found to be associated with false‐negative and ‐positive results. Conclusions. Color Doppler twinkling artifacts are additional useful sonographic signs in the diagnosis of calcified lesions, urinary and biliary stones, gallbladder adenomyomatosis, and some miscellaneous conditions.

CT Findings of Colonic Complications Associated with Colon Cancer

A broad spectrum of colonic complications can occur in patients with colon cancer. Clinically, some of these complications can obscure the presence of underlying malignancies in the colon and these complications may require emergency surgical management. The complications of the colon that can be associated with colon cancer include obstruction, perforation, abscess formation, acute appendicitis, ischemic colitis and intussusception. Although the majority of these complications only rarely occur, familiarity with the various manifestations of colon cancer complications will facilitate making an accurate diagnosis and administering prompt management in these situations. The purpose of this pictorial essay is to review the CT appearance of the colonic complications associated with colon cancer.

Pancreatic carcinoid tumor with obstructive pancreatitis: multislice helical CT appearance: case report

Carcinoid tumor of the pancreas is rare. Moreover, obstructive pancreatitis secondary to a pancreatic carcinoid tumor is extremely rare. We report a case of pancreatic carcinoid tumor in a 50-year-old male who presented with pancreatitis. On multislice helical computed tomography, the main pancreatic duct was obstructed by a small round tumor, and the main pancreatic duct proximal to the tumor was dilated. The correlation between the main pancreatic duct and the tumor was well depicted on minimum intensity projection image. This is the first report of multislice helical computed tomorgraphic and minimum intensity projection image findings of a pancreatic carcinoid tumor presenting with pancreatitis

Duplication of the Extrahepatic Bile Duct in Association with Choledocholithiasis as Depicted by MDCT

We report here on an extremely rare case of duplicated extrahepatic bile ducts that was associated with choledocholithiasis, and this malady was visualized by employing the minimum intensity projection images with using multi-detector row CT. The presence of duplicated extrahepatic bile ducts with a proximal communication, and the ducts were joined distally and they subsequently formed a single common bile duct, has not been previously reported.

Foreign Body Granulomas Simulating Recurrent Tumors in Patients Following Colorectal Surgery for Carcinoma: a Report of Two Cases

We report here two cases of foreign body granulomas that arose from the pelvic wall and liver, respectively, and simulated recurrent colorectal carcinomas in patients with a history of surgery. On contrast-enhanced CT and MR images, a pelvic wall mass appeared as a well-enhancing mass that had invaded the distal ureter, resulting in the development of hydronephrosis. In addition, a liver mass had a hypointense rim that corresponded to the fibrous wall on a T2-weighted MR image, and showed persistent peripheral enhancement that corresponded to the granulation tissues and fibrous wall on dynamic MR images. These lesions also displayed very intense homogeneous FDG uptake on PET/CT.

Transient arterial enhancement of the hepatic parenchyma in patients with acute cholangitis.

Objectives: Our objectives were to determine the clinical significance of transient arterial enhancement (TAE) of the hepatic parenchyma in patients with suspected biliary disease and to investigate the relationship between the pattern and extent of TAE and acute cholangitis. Methods: A retrospective review of dynamic computed tomographic scans in 76 patients with suspected biliary disease was performed. Patterns of TAE were classified as polymorphous, sectorial, peribiliary, diffuse, and a combination of features. The extent of TAE was evaluated by counting the involved liver segments. The extent of TAE was correlated with laboratory and clinical findings. Patients were also divided into 2 groups: cholangitis group (n = 40) and noncholangitis group (n = 36). The pattern and extent of TAE were compared between these 2 groups. Results: Among the laboratory findings that showed significant correlation with the extent of TAE, the white blood cell count and C-reactive protein concentration were found to have a relatively high correlation (r = 0.540 and 0.514, respectively). The presence of abdominal pain, fever, and cholangitis showed a statistically significant difference with the extent of TAE (P < 0.01). Statistically significant differences in the pattern and extent of TAE between the 2 groups were found (P < 0.001). Diffuse or diffuse heterogeneous TAE patterns that involve more than 5 liver segments, such as a polymorphous combined with a peribiliary pattern and a diffuse pattern, had a high association with acute cholangitis. Conclusions: Transient arterial enhancement in patients with suspected biliary disease is well correlated with clinical parameters suggestive of inflammation. Transient arterial enhancement provides useful complementary information for biliary infection in the computed tomographic diagnosis of acute cholangitis.

Three-dimensional reconstructed images using multidetector computed tomography in evaluation of the biliary tract

The recent development of multidetector computed tomography (MDCT) and the parallel escalation in the capabilities of the workstation allow the use of high-quality multiplanar and three-dimensional reconstruction images. As a noninvasive technique, MDCT dedicated to the biliary tract represents an alternative to magnetic resonance cholangiography. The usefulness of three-dimensional reconstructed images using MDCT in evaluating biliary tract abnormality is illustrated.

Epstein-Barr Virus-Associated Lymphoepithelioma-Like Gastric Carcinoma Presenting as a Submucosal Mass: CT Findings with Pathologic Correlation

A lymphoepithelioma-like carcinoma, characterized by a carcinoma with heavy lymphocyte infiltration, is one of the histological patterns observed in patients with Epstein-Barr virus (EBV)-associated gastric carcinoma. Less than half of invasive carcinomas with lymphoepithelioma-like histology can grow to make a submucosal mass. These tumors generally have a better prognosis than conventional adenocarcinomas. We report a case of an EBV-associated lymphoepithelioma-like gastric carcinoma that presented as a submucosal mass on multi-detector (MD) CT and correlate them with the pathology.

Diffuse pattern of transient hepatic attenuation differences in viral hepatitis: a sign of acute hepatic injury in patients without cirrhosis.

Objectives: Our objective was to describe the transient hepatic attenuation differences (THADs) on dynamic computed tomography in patients with viral hepatitis who had no evidence of cirrhosis. Methods: After excluding patients who had known causative factors for the development of THAD, a retrospective review of dynamic CT scans in 67 patients with viral hepatitis was performed to determine whether THAD was present. The patients were assigned to 3 groups according to the magnitude of alanine aminotransferase (ALT) level alteration (normal to mild, moderate, and marked) or hepatitis type (acute hepatitis, acute exacerbation of chronic hepatitis, and chronic infection), and differences in the presence of various CT features including THAD among these groups were evaluated. Results: Five THADs observed had a focal pattern, and 18 THADs had a diffuse pattern. All of the diffuse THADs were observed in patients with marked ALT level alteration (ALT level > 400 IU/L) and in patients with a clinical diagnosis of acute hepatitis or acute exacerbation of chronic hepatitis. In addition, there were significant differences of the presence of other CT findings including hepatomegaly, periportal tracking, gallbladder wall thickening, perihepatic lymphadenopathy, and splenomegaly among these groups (each P < 0.05). Conclusions: A diffuse THAD of the liver and other CT features indicates acute hepatic injury in patients with viral hepatitis who have no clinical evidence of cirrhosis.