MR findings of Dysembryoplastic Neuroepithelial Tumor

ABSTRACT

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.