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Epilepsy surgery involves a neurosurgical procedure where an area of the brain involved in seizures is either resected, disconnected or stimulated. The goal is to eliminate seizures or significantly reduce seizure burden. Approximately 60% of all people with epilepsy (0.4% of the population of industrialized countries) have focal epilepsy syndromes. In 15 to 20% of these patients, the condition is not adequately controlled with anticonvulsive drugs. Such patients are potential candidates for surgical epilepsy treatment. First line therapy for epilepsy involves treatment with anticonvulsive drugs, also called antiepileptic drugs. Most patients will respond to one or two different medication trials. The goal of this treatment is the elimination of seizures, since uncontrolled seizures carry significant risks, including injury and sudden death. However, in up to one third of patients with epilepsy, medications alone do not eliminate seizures, and/or cause adverse effects. In these patients, epilepsy surgery is considered as an alternate treatment method to medications. Generally, surgery is considered in patients whose seizures cannot be controlled by adequate trials of two different medications. Epilepsy surgery has been performed for more than a century, but its use dramatically increased in the 1980s and 1990s, reflecting its efficacy in selected patients. ==Evaluation== The evaluation for epilepsy surgery is designed to locate the "epileptic focus" (the location of the epileptic abnormality) and to determine if resective surgery will affect normal brain function. Resective surgery involves the resection, or cutting away, of brain tissue from the area of the brain that consists of the epileptic focus. Physicians will also confirm the diagnosis of epilepsy to make sure that spells arise from epilepsy (as opposed to non-epileptic seizures). The evaluation typically includes neurological examination, routine EEG, Long-term video-EEG monitoring, neuropsychological evaluation, and neuroimaging such as MRI, Single photon emission computed tomography (SPECT), positron emission tomography (PET). Some epilepsy centers use intracarotid sodium amobarbital test (Wada test), functional MRI (fMRI) or Magnetoencephalography (MEG) as supplementary tests. If noninvasive testing was inadequate in identifying the epileptic focus or in distinguishing the surgical target from normal brain tissue and function, then Long-term video-EEG monitoring with the use of intracranial electrodes may be required for evaluation. Brain mapping by the technique of cortical electrical stimulation or Electrocorticography are other procedures used in the process of invasive testing for certain patients. Once the epilepsy focus is located, the specific surgery involved in treatment is decided on. The type of surgery depends on the location of the seizure focal point. Surgeries for epilepsy treatment include, but are not limited to, the following types: temporal lobe resection, hemispherectomy, ground temporal and extratemporal resection, parietal resection, occipital resection, frontal resection, extratemporal resection, and callosotomy. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Epilepsy surgery」の詳細全文を読む スポンサード リンク
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