title: Seizure outcome after extratemporal epilepsy surgery in childhood.
abstract: OBJECTIVE
  The aim of the study was to describe seizure outcome following surgery for focal extratemporal epilepsy and identify factors associated with prolonged postsurgical freedom from seizures.
  
  
  METHODS
  In this retrospective cohort study, children with drug-resistant focal extratemporal epilepsy were treated surgically and followed up in a single tertiary care centre between 1997 and 2008.
  
  
  RESULTS
  Eighty children were identified for inclusion in the study (42 males, 38 females; median age 9y 1mo, range 3mo-18y 7mo). The aetiology was identified as focal cortical dysplasia (n=37), low-grade tumour (n=22), tuberous sclerosis (n=9), or non-specific (n=12). Children were followed for a median of 3 years 1 month (range 8mo-10y 7mo) after surgery. Overall, at last follow-up, 50% of the children had been completely seizure free since surgery (Engel class Ia); of these 40 individuals, 15 had discontinued all antiepileptic drugs. Several presurgical factors were associated with a favourable outcome. However, after controlling for confounding factors, aetiology appeared to be the only determinant of long-term seizure outcome as non-specific lesion pathology was associated with seizure recurrence (hazard ratio 10.43; 95% confidence interval 3.26-33.39).
  
  
  CONCLUSIONS
  In 50% of cases, children with surgically treated drug-resistant extratemporal epilepsies have an excellent long-term outcome. The aetiology of the epileptogenic lesion appears to be the only significant determinant of surgical outcome in this population of children. It is difficult to correctly identify non-specific pathology on presurgical magnetic resonance imaging.
authors: Neurosciences Unit, University College London Institute of Child Health and Great Ormond Street Hospital NHS Trust, London, UK. l.d'argenzio@ucl.ac.uk
authors: Luigi
authors: L
authors: D'Argenzio
authors: M Chiara
authors: MC
authors: Colonnelli
authors: Sue
authors: S
authors: Harrison
authors: Thomas S
authors: TS
authors: Jacques
authors: William
authors: W
authors: Harkness
authors: Rod C
authors: RC
authors: Scott
authors: J Helen
authors: JH
authors: Cross
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D002648:Child; D002675:Child, Preschool; D004351:Drug Resistance / Q000502:physiology; D004827:Epilepsy / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D005625:Frontal Lobe / Q000473:pathology / Q000601:surgery*; D006801:Humans; D007223:Infant; D008297:Male; D009778:Occipital Lobe / Q000473:pathology / Q000601:surgery*; D010296:Parietal Lobe / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies; D012640:Seizures / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome