Imaging of intractable paediatric epilepsy

Approximately 20% of paediatric patients with epilepsy are refractory to medical therapies. In this subgroup of patients, neuroimaging plays an important role in identifying an epileptogenic focus. Successful identification of a structural lesion results in a better outcome following epilepsy surgery. Advances in imaging technologies, methods of epileptogenic region localisation and refinement of clinical evaluation of this group of patients in epilepsy centres have helped to widen the spectrum of children who could potentially benefit from surgical treatment. In this review, we discuss ways to optimise imaging techniques, list typical imaging features of common pathologies that can cause epilepsy, and potential pitfalls to be aware of whilst reviewing imaging studies in this challenging group of patients. The importance of multidisciplinary meetings to analyse and synthesise all the non-invasive data is emphasised. Our objectives are: to describe the four phases of evaluation of children with drug-resistant localisation-related epilepsy; to describe optimal imaging techniques that can help maximise detection of epileptogenic foci; to describe a systematic approach to reviewing magnetic resonance imaging of children with intractable epilepsy; to describe the features of common epileptogenic substrates; to list potential pitfalls whilst reviewing imaging studies in these patients; and to highlight the value of multimodality and interdisciplinary approaches to the management of this group of children.