MR findings of Dysembryoplastic Neuroepithelial Tumor

PURPOSE: Dysembryoplastic neuroepithelial tumor (DNET) is a newly described, pathologically benign tumor arising within the supratentorial cortex. We reviewed the MR appearance of five patients with DNET, emphasizing the clinical and radiologic features. MATERIALS AND METHODS: MR images in the five patients (three male and two female) with a history of epileptic seizure and pathologically-proven DNET were retrospectively reviewed. We analyzed the location, configuration, signal intensity, contrast enhancement, vasogenic edema and calcifications of these tomors. RESULTS: The tumors were located mainly in the cortical to subcortical area with very little perifocal mass effect on MR imaging. They were essentially hypointense on T1-weighted imaging, and showed a hyperintense well circumscribed mass on T2-weighted imaging and a thick gyrus-like configuration was retained within the lesions. On contrast enhanced study, focal nodular enhancement was seen in one patient, and multifocal nodular enhancement in two. CONCLUSION: DNET is rare benign tumor resulting in often medically intractable epileptic seizure and shows a characteristic gyriform configuration, well-described lobular tumor margins and sometimes multifocal nodular enhancement. These radiologic features may aid in differentiating DNET from ganglioglioma and other gliomas.

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.

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.