Presurgical Functional MRI in Epilepsy
Epilepsy surgery is performed in patients with medically intractable epilepsies to completely resect or disconnect the “epileptogenic zone” - the cortical area which is indispensable to the generation of the seizures. To achieve therapeutic success the epilecogenic zone must be accurately lateralized and localized. Eloquent brain areas in the vincinity of the surgical target need to be preserved as intraoperative damage may result in postoperative neurological deficits. Therfore electrophysiological measures are applied by means of electroencephalography (EEG) and intraoperative electrocoticography (EcoG). However, functional magnetic resonance imaging (fMRI) has potential to noninvasively lateralize and to localize both, epileptic activity and important brain functions such as sensorimotor function, language and memory. For the latter tasks fMRI has proven clinical feasibility. The application of EEG-correlated ictal and interictal fMRI is still experimental.
KeywordsTemporal Lobe Epilepsy Epilepsy Surgery Epileptogenic Zone Wada Test Interictal Epileptiform Discharge
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