title: Epilepsy surgery in tuberous sclerosis: a systematic review.
abstract: OBJECTIVE
  Tuberous sclerosis complex (TSC) is often associated with intractable epilepsy. Although epilepsy surgery has gained interest in recent years uncertainties exist about which patients are good surgical candidates. A systematic review of the available literature has been undertaken to assess the overall outcome of epilepsy surgery and identify risk factors of seizure recurrence.
  
  
  METHODS
  We searched MEDLINE, Embase, and bibliographies of reviews and book chapters to identify articles published in English since 1960. Twenty-five articles, describing postoperative seizure outcome and type of surgery in 177 TSC patients, were included in this study. Seizure outcome was analyzed both as seizure freedom and good outcome, including patients with >90% seizure reduction.
  
  
  RESULTS
  Seizure freedom was achieved in 101 patients (57%). Seizure frequency was improved by > 90% in 32 patients (18%). Moderate or severe intellectual disability (IQ < 70) (RR 1.8; 95% CI 1.2-2.8) and the presence of tonic seizures (RR 1.7; 95 % CI 1.2-2.4) were related to seizure recurrence.
  
  
  CONCLUSIONS
  A relation between multiple seizures types with early onset, multiple cortical tubers and multifocal epileptogenicity, and poor outcome is not supported by this systematic analysis. Although there is considerable variation among studies reviewed here, the literature suggests that resective surgery may offer benefit in a selected population of TSC patients with drug-resistant epilepsy.
authors.affiliation: Department of Child Neurology, Rudolf Magnus Institute of Neuroscience and Julius Centre for Health Sciences and Primary Care, University Medical Centre, 3508 GA Utrecht, The Netherlands. f.e.jansen@umcutrecht.nl
authors.forename: Floor E
authors.initials: FE
authors.lastname: Jansen
authors.forename: Alexander C
authors.initials: AC
authors.lastname: van Huffelen
authors.forename: Ale
authors.initials: A
authors.lastname: Algra
authors.forename: Onno
authors.initials: O
authors.lastname: van Nieuwenhuizen
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000927:Anticonvulsants / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D018572:Disease-Free Survival; D004351:Drug Resistance; D004827:Epilepsy / Q000453:epidemiology / Q000601:surgery*; D005260:Female; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D055502:Secondary Prevention; D016896:Treatment Outcome; D014402:Tuberous Sclerosis / Q000453:epidemiology / Q000601:surgery*
chemical_list: D000927:Anticonvulsants