Seizure Freedom in Children With Pathology-Confirmed Focal

OBJECTIVE: We evaluated the temporal course of seizure outcome in children with pathology-confirmed focal cortical dysplasia and explored predictors of sustained seizure freedom. METHODS: We performed a single-center retrospective study of children � 18 years who underwent resective surgery from January 1, 2000 through December 31, 2012 and had pathology-proven focal cortical dysplasia. Surgical outcome was classified as seizure freedom (Engel class I) or seizure recurrence (Engel classes II-IV). Fisher exact and nonparametric Wilcoxon ranksum tests were used, as appropriate. Survival analysis was based on seizure-free outcome. Patients were censored at the time of seizure recurrence or seizure freedom at last follow-up. RESULTS: Thirty-eight patients were identified (median age at surgery, 6.5 years; median duration of epilepsy, 3.3 years). Median time to last follow-up was 13.5 months (interquartile range, 7-41 months). Twenty patients (53%) were seizure free and 26 patients (68%) attained seizure freedom for a minimum of 3 months. Median time to seizure recurrence was 38 months (95% confidence interval, 6-109 months), and the cumulative seizure-free rate was 60% at 12 months (95% confidence interval, 43%-77%). Clinical features associated with seizure freedom at last follow-up included older age at seizure onset (P ¼ .02), older age at surgery (P ¼ .04), absent to mild intellectual disability before surgery (P ¼ .05), and seizure freedom for a minimum of 3 months (P < .001). CONCLUSION: Favorable clinical features associated with sustained seizure freedom included older age at seizure onset, older age at surgery, absent or mild intellectual disability at baseline, and seizure freedom for a minimum of 3 months.