Multistage epilepsy surgery: Safety, efficacy, and utility of a novel approach in pediatric extratemporal epilepsy

Objective: To evaluate the safety, efficacy, and utility of a novel surgical strategy consisting of multiple (more than two) operative stages performed during the same hospital admission with subdural grid and strip electrodes in selected pediatric extra-temporal epilepsy. Methods: Subdural grid and strip electrodes were used for multistage chronic electroencephalographic monitoring in 15 pediatric patients (age, < 19 yr) with refractory localization-related epilepsy and poor surgical prognositic factors. Initial resective surgery and/or multiple subpial transections were performed, followed by further monitoring and additional resection and/or multiple subpial transections. Results: Mean patient age was 9.7 years. Mean duration of total invasive monitoring was 10.5 days (range, 8 - 14 d). The first monitoring period averaged 6.5 days, and the second averaged 3.9 days. Additional surgery was performed in 13 of 15 patients. Two patients who did not undergo additional surgery had a Class I outcome. Rationales for reinvestigation included incomplete localization, multifocality, and proximity to eloquent cortex. Complications were minimal, including tow transfusions. There were no cases of wound infection, cerebral edema, hemorrhage, or major permanent neurological deficit. Minimum duration of follow-up was 31 months. Outcomes were 60% Engel Class I (9 or 15 patients), 27% Class III (4 of 15 patients), and 13% Class IV (2 of 15 patients) Conclusion: In a very select group of pediatric patients with poor surgical prognostic factors, the multistage approach can be beneficial. After failed epilepsy surgery, subsequent reoperation with additional intracranial investigation traditionally is used when a single residual focus is suspected. Our results, however, support the contention that multistage epilepsy surgery is safe, effective and useful in a challenging and select pediatric population with extratemporal medically refractory epilepsy.