MR Findings of Extraabdominal Fibromatosis

PURPOSE: To evaluate the MR findings of extra-abdominal fibromatosis and the role of MRI in primary diagnosis MATERIALS AND METHODS: Fifteen cases in of histologically proven extra-abdominal fibromatosis in 13 patients were retrospectively reviewed. T1-weighted and T2-weighted images were obtained in axial, coronal and sagittal planes. Gd-enhancement was performed in 14 cases, and dynamic enhancement studies in two. All lesions were evaluated for mass shape and margin definition. RESULTS: Among the 15 cases, tumors of the buttock accounted for five, and tumor of the thigh for two. In eight cases tumors were intermuscular and in six cases were intramuscular. In ten cases (67 %) the mass extended along the long axis of the body and in 14 of 15 cases (93%) focal infiltration of adjacent structures was visible. The signal intensity of the lesion was in all cases inhomogeneous on both T1 and T2 weighted images. As seen on Gd-DTPA enhanced scans, the masses were inhomogeneously enhanced. In all cases MRI revealed star-shaped linear strands or a band-like low signal area in the mass. These features were not enhanced and were arranged along the long axis of the mass. CONCLUSION: MR findings of extra-abdominal fibromatosis were relatively characteristic and helpful for primary diagnosis of the condition.

The Value of CT in detecting Pathologic Bowel Perforation

PURPOSE: To evaluate the usefulness of CT for assessing the location and cause of pathologic gastrointestinal perforation. MATERIALS AND METHODS: A retrospective analysis of abdominal CT was performed in 27 perforations of 26 patients with underlying gastrointestinal pathology. Fifteen benign and 12 malignant perforations consisted of five gastric cancers, one gastric ulcer, ten duodenal bulb ulcers, two bowel adhesions, one jejunal metastasis from lung cancer, one ileocolic Crohn's disease, one radiation colitis and six colon cancers. CT scans were evaluated for 1) diagnosis of bowel perforation, 2) assessment of the cause and site of perforation, and, in particular, differentiation between benignancy and malignancy, and 3) complications and their extent. RESULTS: CT easily detected varying amounts of free air or fluid collection, and infiltration or abscess formation adjacent to the main lesion, and the diagnosis of gastrointestinal perforation was therefore easy. In 11 of the 12 malignancies (92%), primary tumor was diagnosed, but detection of the site of perforation was possible in only seven cases (7/12, 58%). The 15 benign lesions revealed nonspecific CT findings, and the perforation site could be presumed in six (6/15, 40%). In one case of Crohn's disease, the primary cause was visualized. Among six colonic cancers, four pericolic abscesses and two fistulas to adjacent organs were found, but there was no evidence of diffuse peritonitis. CONCLUSION: CT was helpful to lead to optimal treatment of pathologic gastrointestinal On CT, the detectability of perforation, primary benign or malignant lesion, perforation site and extent of complication was high, and this modality was therefore a useful indicator of the optimal treatment for pathologic gastrointestinal perforations.

Usefulness of Dynamic Magnetic Resonance Imaging in Pituitary Microadenomas

PURPOSE: To investigate the usefulness of dynamic MR imaging in the diagnosis of pituitary microadenomas. MATERIALS AND METHODS: Dynamic MR imaging was performed in 31 patients with suspicious pituitary microadenoma. The MR examination was performed on a 2.0T or 1.5T superconductive MR unit using spin echo(SE) technique with arepetition time of 200m sec, echo time of 15 m sec, 128 x 256 matrix and one excitation. Actual sampling time perimage was 26 seconds. The field of view was 25cm and a section thickness of 3mm with 2mm gap was chosen. After arapid hand injection(2-3ml/sec) of Gd-DTPA(0.1 mmol/kg of body weight), dynamic coronal plane MR images were obtained every 20-30 seconds for 3-5 minutes. Between never and ten serial images were usually obtained. After dynamic MR imaging, routine SE T1-weighted images(T1WI) were obtained in the same plane as dynamic images, and detection rates of pituitary microadenoma using dynamic MR imaging and using routine enhanced T1WI, were retrospectively compared. RESULTS: On early dynamic images(30|90 seconds), 23 of 31 adenomas(74.2%) were well visualized, with a clear border ; of particular note is the fact that 11 of the 31 were well visualized at 30-second dynamic image. On late dynamic images(120-180 seconds), six microadeomas(19.4%) were well-visualized and; two(6.5%) were well-visualized throughout on all dynamic images. Meanwhile, 12 of 31 microadenomas(38.7%) were well-visualized on routine Gd-DTPA enhanced T1WI. CONCLUSION: Dynamic MR imaging with Gd-DTPA bolus injection was the most useful technique for the detection of pituitary microadenomas, especially on early-phase dynamic images.

Pelvic Actinomycosis

PURPOSE: To demonstrate the radiologic characteristics of the pelvic actinomycosis. MATERIALS AND METHODS: We retrospectively reviewed the radiologic findings of seven patients with pathologically proven pelvic actinomycosis and analyzed the anatomical location, characteristics of the lesion and alteration of surrounding structures. RESULTS: The location of the lesions were the ovary and adnexa(n=4), rectum(n=1), cecum and terminalileum(n=1), and bladder(n=1). Three of the seven patients had a past history of intrauterine devices.Post-contrast enhanced CT showed an ill-defined mass with inhomogeneous enhancement and a tendency to invade th esurrounding normal tissue plane. CONCLUSION: Pelvic actinomycosis should be included in differential diagnosis when an unusually aggressive infiltrative mass is located in the pelvic cavity, especially in a patient with long-term use of intrauterine contraceptive devices.

Usefulness of Automated Biopsy Guns in Image-guided Biopsy

PURPOSE: To evaluate the usefulness of automated biopsy guns in image-guided biopsy of lung, liver. pancreas and other organs. MATERIALS AND METHODS: Using automated biopsy devices, 160 biopsies of variable anatomic sites were performed:Biopsies were performed under ultrasonographic(US) guidance in 95 and computed tomographic (CT) guidance in 65. We retrospectively analyzed histologic results and complications. RESULTS: Specimens were adequate for histopathologic diagnosis in 143 of the 160 patients(89.4%)-Diagnostic tissue was obtained in 130 (81.3%), suggestive tissue obtained in 13(8.1%), and non-diagnostic tissue was obtained in 14(8.7%). Inadequate tissue was obtained in only 3(1.9%). There was no statistically significant difference between US-guided and CT-guided percutaneous biopsy. There was no occurrence of significant complication. We have experienced mild complications in only 5 patients-2 hematuria & 2 hematochezia in transrectal prostatic biopsy, and 1 minimal pneumothorax in CT-guided percutaneous lung biopsy. All of them were resolved spontaneously. CONCLUSION: The image-guided biopsy using the automated biopsy gun was a simple, safe and accurate method of obtaining adequate specimen for the histopathologic diagnosis.