Selection and evaluation of the candidate patient for epilepsy surgery

Abstract

Surgery for epilepsy refractory to medical treatment is a promising therapeutic option. Major determinants of the success of epilepsy surgery are the proper selection and evaluation of the patient. Candidates should have medically intractable epilepsy, defined in most centers as a failure of at least two first-line antiepileptic medications due to the lack of efficacy. The presurgical work-up of patients consists of a Phase I evaluation including magnetic resonance imaging, videoelectroencefalography, neuropsychological testing, psychiatric evaluation and functional imaging techniques. Following the Phase I evaluation, the epilepsy surgery team (consisting of the neurologist/ epileptologist, neurosurgeon, neuroradiologist, neuropsychologist and psychiatrist) reviews all of the data collected, and decides if epilepsy surgery would likely lead to a reduction in seizure frequency without significant side effects. As the results of surgery are best when there is congruence between seizure semiology, irritative zone on interictal EEG, and ictal onset zone, some additional tests are often necessary, such as intracranial electroencephalographic monitoring and cortical functional mapping.