title: Dysembryoplastic neuroepithelial tumors: MR and CT evaluation.
abstract: OBJECTIVE
  To evaluate dysembryoplastic neuroepithelial tumors (DNTs) on MR and CT studies and to compare DNT with other frequently encountered epileptogenic glioneuronal lesions.
  
  
  METHODS
  We analyzed the MR images and CT scans of 16 patients who had complex partial epilepsy and DNT with respect to tumor location, size, CT density, MR signal intensity, mass effect, contrast enhancement, and heterogeneity, and compared these features with CT and MR findings in 51 cases of ganglioglioma and 33 cases of glioneuronal malformation.
  
  
  RESULTS
  DNTs were located in the temporal lobe in 14 patients and in the frontal lobe in 2 patients. The cortex was involved in all cases and the subcortical white matter in 10 cases. Fifty percent of the tumors had poorly defined contours. On MR images, 14 DNTs had multiple cysts and 2 had single cysts. Contrast enhancement was observed in 6 DNTs, and mass effect was present in 9. CT scans disclosed moderately hypodense lesions in 7 patients and markedly hypodense cystic lesions in 6 patients. Two DNTs were calcified. Tumor hemorrhage with perifocal edema was observed in 1 case. Contrary to previous reports, slow but definite tumor growth was present during a 13-year period in 2 of 6 patients in whom serial CT or MR studies were obtained.
  
  
  CONCLUSIONS
  A multicystic appearance on MR images is a characteristic feature of DNT and corresponds to its myxoid matrix and multinodular architecture. This feature is rare in gangliogliomas and glioneuronal malformations, and, as such, may help differentiate DNTs from these disorders.
authors.affiliation: Department of Neuroradiology/Radiology, University of Bonn, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Ostertun
authors.forename: H K
authors.initials: HK
authors.lastname: Wolf
authors.forename: M G
authors.initials: MG
authors.lastname: Campos
authors.forename: C
authors.initials: C
authors.lastname: Matus
authors.forename: L
authors.initials: L
authors.lastname: Solymosi
authors.forename: C E
authors.initials: CE
authors.lastname: Elger
authors.forename: J
authors.initials: J
authors.lastname: Schramm
authors.forename: H H
authors.initials: HH
authors.lastname: Schild
mesh_terms: D000293:Adolescent; D000328:Adult; D001932:Brain Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D017029:Epilepsy, Complex Partial / Q000150:complications; D005625:Frontal Lobe; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018241:Neuroectodermal Tumors, Primitive, Peripheral / Q000150:complications / Q000175:diagnosis* / Q000473:pathology; D010296:Parietal Lobe; D014057:Tomography, X-Ray Computed