Frequency and significance of acute postoperative seizures following epilepsy surgery in children and adolescents

Abstract

Purpose: To determine the frequency and prognostic features of acute postoperative seizures (APOSs), within the first postoperative week, in a group of children undergoing surgery for the treatment of medically refractory epilepsy. Methods: Patients younger than 18 years who underwent surgery for the relief of medically intractable epilepsy at the Mayo Clinic between 1985 and 1998 with a minimum of 12 months of follow-up were eligible. A retrospective chart review was conducted to abstract information regarding demographics, epilepsy history, and preoperative, intraoperative, and postoperative risk factors, APOSs, and outcome. A multivariate analysis was conducted to control for confounding variables. Results: The study group was composed of 148 patients (mean age at surgery, 13 years; range, 5 months to 18 years). Twenty-five percent of patients experienced APOSs. Risk factors associated with a statistically significant (p < 0.05) greater likelihood of experiencing APOS were non-complex partial seizure type, extratemporal surgery, postoperative fever, non-temporal lobe epilepsy, and postoperative interictal epileptiform activity. At last follow-up, patients who did not experience APOSs had a significantly greater chance of being seizure free (80 vs. 51%; p < 0.001). With a multivariate analysis, APOS was found to be an independent predictor of outcome. Conclusions: This study indicates that APOSs are predictive of a less favorable outcome in the pediatric postsurgical patient; however, 51% remained seizure free at last follow-up. Finally, the effects of APOSs on outcome were shown to be stable over a 12-month follow-up period.