Neuroimaging of epilepsy

Abstract

Neuroimaging is an integral part of clinical evaluation of epilepsy, and fundamental in delineating structural abnormalities for surgical intervention. The common causes of epilepsy presenting in childhood and young adults that often require surgical intervention include congenital or developmental malformations (such as focal cortical dysplasia, hemimegalencephaly, malformation of cortical development and lissencephaly), phakomatoses (including tuberous sclerosis and Sturge–Weber syndrome), hippocampal sclerosis, vascular malformations and tumors. MRI is the most important imaging modality in depicting the site and type of structural abnormalities in these entities, and examples will be shown. However, not all lesions are readily identified on conventional MRI, and complementary information may be obtained by advanced imaging techniques such as MR spectroscopy and DTI, and nuclear medicine techniques such as SPECT and PET. Mesial temporal sclerosis is the most frequent pathological finding in temporal epilepsy but may be challenging to diagnose; current advances in imaging including high–field (7T) structural imaging and quantitative analysis will be presented.