Imaging Analysis of Colonic Villous Tumors

PURPOSE: To evaluate the CT and US features of the colonic villous tumors. MATERIALS AND METHODS: We retrospectively reviewed the CT findings of 11 cases with histologically proved colonic villous tumor. CT parameters evaluated were morphological appearances and enhancing pattern (size, shape, margin, presence or absence of fronds, bowel wall thickening). CT features of six cases with malignant change were compared with five tumors without malignant change. US features available in 10 patients were also analyzed. RESULTS: On CT, thetumors showed irregular margin(n=9), presence of fronds(n=6), lobulated shape(n=11), with pericolonic invasion(n=1). Six cases with malignant change were larger(mean, 6.8cm in diameter) than those without malignant change(mean, 3.3 cm). US features in 10 cases were intraluminal mass(n=5), colonic wall thickening(n=5), with variable echogenicity. CONCLUSIONS: Colonic villous tumor appeared as a nonspecific mass on CT and US with adifficulty in distinguishing from colon carcinoma.

The Significance of Echogenic Rim of Atypical Hepatic Hemangioma on Ultrasonogram

PURPOSE: To evaluate whether the presence of a peripheral echogenic rim surrounding internal low echogenicityis helpful in the diagnosis of atypical hepatic hemangioma. MATERIALS AND METHODS: Within a two-year period, aretrospective review of the sonographic appearances of 24 atypical hemangiomas in 21 patients was performed. Diagnosis was made by dynamic and delayed enhanced CT, MR imaging or clinical follow up for one year, including follow-up sonogram. The sonographic appearances of these hemangiomas were analyzed for pattern and thickness ofthe echogenic rim, internal echo pattern, shape, and size. Additionally, forty six lesions of hepatoma, metastasis, abscess and intrahepatic cholangiocarcinoma confirmed by pathology within the same period were also evaluated for the presence of echogenic rim. RESULTS: Twenty-three of 24 lesions showed an echogenic rim ; these were thick in nine cases, and thin in 14 cases. The thickness of the rim was either uniform(n=10) or eccentric(n=13). The average maximum diameter of atypical hemangioma was 4.4cm (range of diameters, 1.5-12cm). The internal echo pattern was partially or entirely hypoechoic in 15 lesions, homogeneously isoechoic in three, and mixed insix cases. Twenty-one lesions were round, and the shape of three was irregular. The other forty six masses including hepatocellular carcinoma, metastases, cholangiocarcinoma and hepatic abscesses did not show an echogenicrim. CONCLUSIONS: The presence of a sonographic echogenic rim in a hepatic mass may help in the diagnosis ofhepatic hemangioma.

Evaluation of the Safety of Iatrogenic Intestinal Perforation during Placement of Percutaneous Drainage Catheter in Rabbit

PURPOSE: To evaluate the safety of transgression of the bowel during intraperitoneal percutaneous catheter placement in an animal model. MATERIALS AND METHODS: Eight 8-F straight catheters were percutaneously insertedinto the small and large bowel of eight rabbits. In four animals, the catheters were left in place until autopsy, whereas in the remaining four, the catheters were withdrawn five days after insertion. Autopsy was performed inall animals ten days after catheter placement, and gross and microscopic examination was carried out. RESULTS: Transgressing the bowel during intraperitoneal percutaneous catheter placement did not contribute to any clinically significant complications. At autopsy, there was no bowel leakage, peritonitis, or abscess, although peritoneal adhesions were found around the catheter tract. CONCLUSION: Although further study is warranted, ourstudy with an animal model indicated that transgression of the intestine during percutaneous placement of an intraabdominal catheter did not produce significant complications.

Percutaneous Transhepatic Biliary Drainage(PTBD): Comparative Data of Right and Left Hepatic Lobe Approach

PURPOSE: To evaluate the difference in each procedure time and complication rates related to percutaneous transhepatic biliary drainage(PTBD) via the right and the left hepatic lobe. MATERIALS AND METHODS: We performed PTBD in 120 patients with biliary obstruction below both main hepatic ducts. Of the 120 catheters, 54 were introduced via a left lobe approach and 66 through the right lobe. All procedures were performed under fluoroscopic guidance by the same operator. For each patient, procedure time was recorded prospectively. PTBD related complications were classified as either early(up to 30 days after procedure) or late(after 30 days), and each complication graded as major, or minor according to its intensity. RESULTS: The difference in the mean procedure time(28.8min versus 36.2rain, left versus right approach group) and that in complication rates (37% versus 58%) were statistically significant(p<0.05). Concerning major complications(bile peritonitis, sepsis, massive hemobilia, liver abscess, pyothorax), the percentages related to left and right lobe approach were 1.8% and 10.6%, and concerning minor complications(catheter obstruction or dislodgement, transient hemobilia, persistent fever or pain), the percentages were 36%and 51%respectively. CONCLUSIONS: PTBD via the left lobe approach was superior with short procedure time and low complication rates than the right approach.

Dysphagia with Malignant Stricture of Esophagogastric Junction:Treatment with Self-expandable Nitinol Stent

PURPOSE: To evaluate the effectiveness, patency and safty of a self-expandable nitinol stent for palliative treatment of malignant stricture of gastroesophageal junction. MATERIALS AND METHODS: An esophageal stent was inserted in five consecutive patients with malignant stricture of esophagogastric junction. Histologicaily, four cases were adenocarcinoma, and one was squamous cell carcinoma. The location and severity of stricture were evaluated with gastrografin just before stent insertion. In one patient with past subtotal gastrectomy, esophagography revealed fistulous tract at stricture site. RESULTS: No technical failure or procedural complications occurred, and improvement of dysphagia was noted in all patients soon after stent insertion. On follow up esophagograms performed 3 to 7 days after stent insertion, all stents were completely expanded and unchanged in positions. In one patient with fistulous connection at stricture site, esophagogram immediately after the procedure revealed complete occlusion of the fistula. Three patients died within 4, 7 and 8 consecutive months after stent insertion. Two patients are alive maintaining adequate body weight and passing most diet. CONCLUSIONS: Self-expandable nitinol stent with it's good longitudinal flexibility and efficient radial force was effective in the palliative treatment of dysphagia in patient with malignant stricture at esophagogastric junction.