This study was performed to assess the usefulness of magnetoencephalography (MEG) as a presurgical evaluation modality in Korean pediatric patients with lesional localization-related epilepsy. The medical records and MEG findings of 13 pediatric patients (6 boys and 7 girls) with localization-related epilepsy, who underwent epilepsy surgery at Seoul National University Children's Hospital, were retrospectively reviewed. The hemispheric concordance rate was 100% (13/13 patients). The lobar or regional concordance rate was 77% (10/13 patients). In most cases, the MEG spike sources were clustered in the proximity of the lesion, either at one side of the margin (nine patients) or around the lesion (one patient); clustered spike sources were distant from the lesion in one patient. Among the patients with clustered spike sources near the lesion, further extensions (three patients) and distal scatters (three patients) were also observed. MEG spike sources were well lateralized and localized even in two patients without focal epileptiform discharges in the interictal scalp electroencephalography. Ten patients (77%) achieved Engel class I postsurgical seizure outcome. It is suggested that MEG is a safe and useful presurgical evaluation modality in pediatric patients with lesion localization-related epilepsy.
Adolescent ; Brain/radionuclide imaging ; Brain Diseases/pathology ; Child ; Child, Preschool ; Epilepsies, Partial/pathology/*surgery ; Female ; Ganglioglioma/pathology ; Humans ; Infant ; Magnetic Resonance Imaging ; *Magnetoencephalography ; Male ; Malformations of Cortical Development/pathology ; Neoplasms, Neuroepithelial/pathology ; Positron-Emission Tomography ; Retrospective Studies ; Seizures/diagnosis

OBJECTIVETo study the clinicopathologic features and radiologic findings of dysembryoplastic neuroepithelial tumor (DNT).

METHODSThe clinical presentations, radiologic findings, histologic features and immunophenotype of 9 cases of DNT were analyzed.

RESULTSThe age of patients ranged from 12 to 51 years (mean age = 32 years). Most presented with partial seizures, sometimes accompanied by transient aphasia, agraphia and decreased visual acuity. One case was asymptomatic and discovered incidentally during a routine check-up. All patients had no neurological deficit found on physical examination. All tumors were located in the supratentorial cerebral cortex. There was no peritumoral edema or space-occupying effect on radiologic examination. The tumors involved either frontal lobe (number = 4), temporal lobe (number = 4), frontoparietal lobe (number = 1) . Two cases showed cystic changes. Two histologic variants of DNT were recognized: simple (number = 3) and complex (number = 6). Simple variant was composed mainly of the glioneuronal element, accompanied by surrounding oligodendrocyte-like cells, and the complex variant contained a low-grade glioma component, in addition to the glioneuronal element and sometimes foci of cortical dysplasia.

CONCLUSIONSDNT is a benign tumor with excellent prognosis after surgical excision. Local recurrence is rare. Complex variant of DNT needs to be distinguished from other types of low-grade glioma.

Adolescent ; Adult ; Brain Neoplasms ; complications ; metabolism ; pathology ; surgery ; Cerebral Cortex ; metabolism ; pathology ; Child ; Child, Preschool ; Epilepsies, Partial ; etiology ; metabolism ; pathology ; surgery ; Female ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Neuroectodermal Tumors, Primitive ; complications ; metabolism ; pathology ; surgery ; Neurofilament Proteins ; metabolism ; Oligodendroglia ; pathology ; ultrastructure ; S100 Proteins ; metabolism ; Survival Rate ; Synaptophysin ; metabolism