Neuroimaging in pediatric epilepsy

The main causes of epilepsy in children are cortical malformations (hemimegalencephaly, cortical dysplasia, lissencephaly, etc.) and phakomatosis (tuberous sclerosis, Sturge-Weber disease, neurofibromatosis type 1, etc.), perinatal ischemia, traumatisms, infections, mesial temporal sclerosis, metabolic diseases, and tumors. Imaging indications are precise, inducing partial seizures and a pathological electroencephalogram. Twenty-five percent of these epilepsy cases are pharmacoresistant. Indeed, MRI is essential to consider surgical treatment, allowing one to localize potential epileptogenic anatomic lesions. The protocol includes sequences in three planes of space, weighted in T1, T2, Flair, T1 inversion-recovery, and T1 after gadolinium injection. MRI findings are characteristic for some tumors, but most malformations are subtle. Consequently recent techniques (spectroscopy, diffusion, etc.) are crucial when conventional MRI is not sufficient. The aim of this article is to illustrate, with a substantive image revue, this wide diversity of etiologies in pediatric epilepsy, in order to help the attendee recognize MRI findings, also discussing the role of newer imaging modalities in this field. (C) 2012 Elsevier Masson SAS. All rights reserved.