MRI-characteristics of epileptogenic supratentorial brain tumors in children

Abstract

To analyze MR-images in patients with symptomatic epilepsy associated with the brain tumor. MRI results of 52 patients with symptomatic epilepsy operated for tumors of supratentorial localization were analyzed. The most epileptogenic tumors with atypical MRI signs and subtle clinical presentation were identified. All patients with tumors were operated using different methods of surgical intervention. Dysembryoplastic neuroepithelial tumors (DNET), diffuse astrocytomas (DA) and gangliogliomas (GG) were the most frequent epileptogenic tumors. In all the cases of DNET and in 4 patients with GG, epileptic seizures were the first, and in 4 of 5 cases of DIO were the only clinical sign of tumor presence. In DNET, DA and GG, there was an iso- or hypointensive signal on T1 WI and a signal varying in intensity from moderate to hyperintense in T2 and FLAIR WI, while in cases with DNET and GG, no mass effect and perifocal edema was practically seen. The so-called «spume-like» (multicystic) structure was most clearly observed in FLAIR WI. No significant changes in the dimensions of the DNET and GG were identified. The combination of DNET with focal cortical dysplasia was noted in one case. In DA, it was difficult to distinguish the perifocal edema from tumorous tissue and normal brain tissues, and the growth potential of malformation was slow. Epileptogenic tumors can imitate the x-ray characteristics of each other, and mimicry to gangliogliomas, oligodendrogliomas and astrocytomas Gr I, II, and others. They are the most frequent causes of symptomatic focal epilepsy. The presence of these malformations is necessary to exclude first of all in all cases of pharmacoresistant epilepsy.