Electrocorticography

Electrocorticography (ECOG), the intra-operative recording of cortical potentials, has played an important role in the surgical management of patients with medically refractory epilepsy. It has been used 1) to localize the epileptogenic tissue; 2) map out cortical functions; and 3) predict the success of the surgery. Despite its common use, few studies have been done to prove its effectiveness in these areas. The technique used in children for recording ECOG is very similar to that used in adults except for the limitations imposed by the child's age. Anaesthesia must often be used. Based upon a computerized medical literature search, a review of this procedure was done. Pre-resection localization, and post-resection prediction of outcome was done for temporal and extra-temporal resection, both lesional and nonlesional. Most of the available studies were in adult patients. All were retrospective in nature. Evidence for the role of pre-resection ECOG in determining the degree of resection felt necessary to obtain good clinical outcome was limited. Similarly the post-resection ECOG predication of surgical outcome was restricted.