ABSTRACT
Brain surgery is an effective treatment for individuals who suffer from medically intractable epilepsy.1-5 Of the over 2 million Americans with epilepsy, 30-40% continue to have seizures despite optimal anticonvulsant treatment.6-8 Of these, it is estimated that at least 30%, or over 200 000 individuals in the USA, would be candidates for epilepsy surgery.8-10 Determination of the appropriateness of surgery requires identification of a brain locus of seizure origin as well as evaluation of the surgical risks. Functional magnetic resonance imaging (fMRI) can potentially contribute to this process in several ways. First, by determining the location of important brain functions, fMRI can help predict the risk of postoperative language, memory, and motor deficits, and during the surgical procedure can be used to minimize such deficits. Second, asymmetries in temporal lobe functional activation can identify diseased brain tissue in which seizures are inferred to originate. Third, techniques for detecting ictal or interictal hemodynamic changes can be used to directly localize epileptic foci.
