Surgery and electrical stimulation in epilepsy: selection of candidates and results

Despite the correct use of antiepileptic drugs, control of seizures is not possible in 20% to 30% of people with epilepsy. This group of patients is considered to suffer from drug-resistant epilepsy, a clinical situation that can be caused by certain syndromes in which surgery can be used to bring the seizures under control.

Determining the suitability of the surgical treatment and the best approach always requires a full assessment, which includes video-electroencephalogram (EEG) monitoring, neuropsychological examination, and structural magnetic resonance imaging. In some patients it may be necessary to perform functional imaging tests and intracranial electrode recordings. These tests make it possible to confirm that the patient does indeed have epilepsy, identify the type of epilepsy, determine the severity of the seizures, and locate the epileptogenic zone. The best surgical results are obtained in patients with small epileptogenic lesions which can be totally resected. Nevertheless, in many patients in whom complete control is not achieved after surgery, the improvement in control of the seizures also has a positive impact on their quality of life. Some surgical techniques (partial resections, corpus callosotomy, subpial transection, electrical stimulation of the vagus nerve, and deep brain stimulation) have a palliative effect.

The aim of this review is to update knowledge on the indications for surgery and electrical stimulation in the management of epilepsy.