When is imaging enough?

Despite tremendous recent advances in both structural and functional neuroimaging, these tests alone are not enough to recommend surgery for medically refractory epilepsy. A detailed history, careful description of the ictal events, and the neurological examination will always be necessary. Interictal EEG and neuropsychological testing also add important information. In many situations, however, video-EEG monitoring of habitual seizures now plays a confirmatory, rather than a primary, role in the presurgical evaluation, and can occasionally contribute confounding data that delay or prevent surgical intervention. In the present climate of cost-containment, it is reasonable to ask if this expensive diagnostic tool is always needed when it is clear by other means that seizures are not psychogenic, particularly in certain pediatric surgically remediably syndromes such as those catastrophic epilepsys of infants and young children amenable to hemispherectomy, and drop attack that can be treated with corpus callosotomy, as well as mesial temporal lobe epilepsy and seizures due to discrete resectable lesions that often become medically intractable in adolescence. Retrospective studies should be carried out to determine when long-term, in-patient, video-EEG monitoring in these conditions add information that appropriately changes the therapeutic approach.