Abstracts

Rationale: The long-term surgical outcome of pediatric epilepsy patients with focal cortical dysplasia (FCD) is not clear. Here, we report on the long-term surgical outcomes of children with FCD, based on longitudinal analyses. Methods: We analyzed retrospectively the records of 41 children who received epilepsy surgery for pathologically proven FCD. Twenty patients were male and 21 patients were female. The median age at surgery was nine years (range, 1-17 years). Results: The actuarial seizure-free rates were 49%, 44%, and 33% in the first, second, and fifth year after surgery, respectively. There was no seizure recurrence after three years. Three patients with initial seizure-control failure experienced late remission of seizures (a running-down phenomenon). Eventually, 19 patients (46%) were seizure-free at their last follow-ups. Absence of a lesion on MRI and incomplete resection were significantly associated with seizure-control failure. Concordance of presurgical evaluation data was an marginally significant variable for seizure control in patients with lesional epilepsy. Three patients with seizure-control failure became seizure-free by the running-down phenomenon. The actuarial rate of antiepileptic drug discontinuation was 91% in the fifth year in the seizure-free patients. Conclusions: The seizure-free rate after surgery in children with FCD was 49% in the first year; however, it declined thereafter. The running-down phenomenon could be an important mechanism of seizure alleviation for FCD patients during long-term follow-up. As a complete resection of FCD has a strong prognostic implication for seizure control, a better method to define the extent of FCD is required to assist with surgical resection, especially in nonlesional epilepsy.