title: Longitudinal change in outcome of frontal lobe epilepsy surgery.
abstract: BACKGROUND
  Although the outcome of epilepsy surgery changes with time, few studies have considered longitudinal changes after frontal lobe epilepsy (FLE) surgery.
  
  
  OBJECTIVE
  To assess the longitudinal changes after FLE surgery.
  
  
  METHODS
  Resection of the seizure onset zone was performed in 76 patients with FLE. Invasive monitoring was performed in 56 of these 76. Awake craniotomy was performed in 43 of the 76 patients. More than 50% of patients were followed up for at least 7 years. The mean follow-up was 81 months.
  
  
  RESULTS
  For all patients, the seizure-free rate was 79% at 6 months, 64% at 1 year, 55% at 2 years, and 55% at 7 years. For patients with cortical dysplasia, the seizure-free rate was 72% at 6 months, 53% at 1 year, 51% at 2 years, and 46% at 7 years. For patients with tumor, the seizure-free rate was 89% at 6 months, 83% at 1 year, 83% at 2 years, and 74% at 7 years. Patients with tumor showed better outcome than those with cortical dysplasia (P = .04). Although the overall seizure-free rate became stable after 2 years, individual status changed for up to 5 years. Seizures recurred in 11 patients within 1 year (early recurrence) and in 12 patients by 1 to 5 years (late recurrence). Antiepileptic drug (AED) medication was adjusted in all patients with recurrence. Patients with late recurrence had a more favorable response (Engel class I or II) than early recurrence (P < .01).
  
  
  CONCLUSIONS
  The overall seizure outcome changes mostly during the first year. However, individual seizure status changes for up to 5 years. The outcome of late recurrence is favorable to AED adjustment.
authors.affiliation: Department of Neurosurgery, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Chi Heon
authors.initials: CH
authors.lastname: Kim
authors.forename: Chun Kee
authors.initials: CK
authors.lastname: Chung
authors.forename: Sang Kun
authors.initials: SK
authors.lastname: Lee
mesh_terms: D000328:Adult; D017034:Epilepsy, Frontal Lobe / Q000453:epidemiology* / Q000601:surgery*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D019635:Neurosurgical Procedures / Q000706:statistics & numerical data*; D015995:Prevalence; D011379:Prognosis; D056910:Republic of Korea / Q000453:epidemiology; D018570:Risk Assessment; D012307:Risk Factors; D016896:Treatment Outcome