To determine long-term efficacy and safety of epilepsy surgery in children and 
adolescents with malformations of cortical development (MCD) and to identify 
differences in seizure outcome of the various MCD subgroups. Special focus was 
set on the newly introduced International League Against Epilepsy (ILAE) 
classification of focal cortical dysplasia (FCD).
STUDY DESIGN: This is a single center retrospective cross-sectional analysis of 
prospectively collected data.
INCLUSION CRITERIA: age at surgery <18 years, pre-surgical evaluation and 
epilepsy surgery performed at the Vienna pediatric epilepsy center, 
histologically proven MCD, complete follow-up data for at least 12 months. 
Clinical variables evaluated: type and localization of MCD, type of surgery and 
a variety of clinical characteristics reported to be associated with 
(un-)favorable outcomes. MCD were classified following the existing 
classification schemes (Barkovich et al., 2012. Brain. 135, 1348-1369; Palmini 
et al., 2004. Neurology. 62, S2-S8) and the ILAE classification for FCD recently 
proposed by Blümcke in 2011. Seizure outcome was classified using the ILAE 
classification proposed by Wieser in 2001.
RESULTS: 60 Patients (51.7% male) were included. Follow up was up to 14 (mean 
4.4 ± 3.2) years. Mean age at surgery was 8.0 ± 6.0 (median 6.0) years; mean age 
at epilepsy onset was 2.9 ± 3.2 (median 2.0) years; duration of epilepsy before 
surgery was 4.8 ± 4.4 (median 3.0) years. 80% of the patients were seizure free 
at last follow-up. AEDs were successfully withdrawn in 56.7% of all patients. 
Extended surgery, lesion localization in the temporal lobes and absence of 
inter-ictal spikes in postsurgical EEG recordings were predictive of favorable 
seizure outcomes after surgery. However, no association was found between 
outcome and MCD sub-types. Epilepsy surgery is highly effective in carefully 
selected drug-resistant children with MCD. Surrogate markers for complete 
resection of the epileptogenic zone remain the only significant predictors for 
seizure freedom after surgery.