RADIOLOGIC APPEARANCE OF THE DYSEMBRYOPLASTIC NEUROEPITHELIAL TUMOR

PURPOSE: To evaluate the computed tomographic (CT) and magnetic resona nce (MR) imaging features of dysembryoplastic neuroepithelial tumor (D NT). MATERIALS AND METHODS: Six CT studies (four with contrast materia l enhancement) and 10 MR imaging studies (seven with gadolinium enhanc ement) obtained in 10 patients with a history of seizures and patholog ically proved DNT were retrospectively reviewed. RESULTS: All tumors w ere intracortical or subcortical. CT showed a low-attenuation mass in all cases except one of mixed isoattenuation and low attenuation. The DNT had decreased signal intensity on T1-weighted MR images and well-d emarcated increased signal intensity on T2-weighted images without per itumoral edema. Prominent MR imaging features were a gyriform configur ation on T1- or T2-weighted images in 10 patients (100%), well-demarca ted lobular tumor margins on T2-weighted images in eight (80%), and a high rate of bone remodeling of the adjacent calvaria on MR (60% [n = 6]) and CT (67% [n = 4]) images. CONCLUSION: Diagnosis of DNT with ima ging modalities alone may be difficult, but these radiologic features may aid in differentiating DNT from other gliomas.