Low-grade Epilepsy-associated Tumors and Other Acquired Causes of Epilepsy: MR Imaging.

Low-grade epilepsy-associated tumors are the second common cause of drug-resistant epilepsy, mostly occurring in young adults. The IDH-wild type tumors ganglioglioma (GG) and dysembryoplastic neuroepithelial tumor (DNET) account for the majority of these tumors. Only DNETs have a specific imaging profile of multilobulated cysts oriented in a ball-like fashion or perpendicular to the cortical surface. GG with a predominant neuronal or glial population are more heterogenous and cannot be clearly separated from pilocytic astrocytomas (PAs), pleomorphic xanthoastrocytomas, angiocentric gliomas, and polymorphous low-grade neuroepithelial tumors of the young, respectively.