Clinical application of experimental cortical dysplasia in rats

This report details clinical and experimental studies of focal cortical dysplasia. The first part deals with 14 surgical cases of children with intractable epilepsy. At surgery, intraoperative electrocorticography was performed to localize the epileptic foci under neuroleptanalgesia. Thirteen patients showed epileptiform discharges on this preresection electrocorticography. All foci in noneloquent areas were resected. Patients who had undergone total lesionectomy with complete focus resection showed the most favorable postoperative results. However, the positive correlation between the intraoperative electrocorticographic findings and the pathologic classification of cortical dysplasia was not found in the present study. Nine patients have been seizure free with reduced medication and two patients have achieved worthwhile improvement. We conclude that intraoperative electrocorticography can improve the surgical outcome for intractable epilepsy by localizing epileptic foci for resection. The second part describes a kainic acid-induced experimental model of focal cortical dysplasia, which demonstrated not only the epileptic properties of the dysplasia but also the perilesional epileptogenicity. The findings supported the surgical results for the patients with focal cortical dysplasia.