title: Predictors of seizure outcomes in children with tuberous sclerosis complex and intractable epilepsy undergoing resective epilepsy surgery: an individual participant data meta-analysis.
abstract: OBJECTIVE
  To perform a systematic review and individual participant data meta-analysis to identify preoperative factors associated with a good seizure outcome in children with Tuberous Sclerosis Complex undergoing resective epilepsy surgery.
  
  
  METHODS
  Electronic databases (MEDLINE, EMBASE, CINAHL and Web of Science), archives of major epilepsy and neurosurgery meetings, and bibliographies of relevant articles, with no language or date restrictions.
  
  
  METHODS
  We included case-control or cohort studies of consecutive participants undergoing resective epilepsy surgery that reported seizure outcomes. We performed title and abstract and full text screening independently and in duplicate. We resolved disagreements through discussion.
  
  
  METHODS
  One author performed data extraction which was verified by a second author using predefined data fields including study quality assessment using a risk of bias instrument we developed. We recorded all preoperative factors that may plausibly predict seizure outcomes.
  
  
  RESULTS
  To identify predictors of a good seizure outcome (i.e. Engel Class I or II) we used logistic regression adjusting for length of follow-up for each preoperative variable.
  
  
  RESULTS
  Of 9863 citations, 20 articles reporting on 181 participants were eligible. Good seizure outcomes were observed in 126 (69%) participants (Engel Class I: 102(56%); Engel class II: 24(13%)). In univariable analyses, absence of generalized seizure semiology (OR = 3.1, 95%CI = 1.2-8.2, p = 0.022), no or mild developmental delay (OR = 7.3, 95%CI = 2.1-24.7, p = 0.001), unifocal ictal scalp electroencephalographic (EEG) abnormality (OR = 3.2, 95%CI = 1.4-7.6, p = 0.008) and EEG/Magnetic resonance imaging concordance (OR = 4.9, 95%CI = 1.8-13.5, p = 0.002) were associated with a good postoperative seizure outcome.
  
  
  CONCLUSIONS
  Small retrospective cohort studies are inherently prone to bias, some of which are overcome using individual participant data. The best available evidence suggests four preoperative factors predictive of good seizure outcomes following resective epilepsy surgery. Large long-term prospective multicenter observational studies are required to further evaluate the risk factors identified in this review.
authors: Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Canada. aria.fallah@mail.utoronto.ca
authors: Aria
authors: A
authors: Fallah
authors: Gordon H
authors: GH
authors: Guyatt
authors: O Carter
authors: OC
authors: Snead
authors: Shanil
authors: S
authors: Ebrahim
authors: George M
authors: GM
authors: Ibrahim
authors: Alireza
authors: A
authors: Mansouri
authors: Deven
authors: D
authors: Reddy
authors: Stephen D
authors: SD
authors: Walter
authors: Abhaya V
authors: AV
authors: Kulkarni
authors: Mohit
authors: M
authors: Bhandari
authors: Laura
authors: L
authors: Banfield
authors: Neera
authors: N
authors: Bhatnagar
authors: Shuli
authors: S
authors: Liang
authors: Federica
authors: F
authors: Teutonico
authors: Jianxiang
authors: J
authors: Liao
authors: James T
authors: JT
authors: Rutka
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004569:Electroencephalography / Q000379:methods; D004827:Epilepsy / Q000601:surgery*; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging / Q000379:methods; D008875:Middle Aged; D012189:Retrospective Studies; D012640:Seizures / Q000601:surgery*; D016896:Treatment Outcome; D014402:Tuberous Sclerosis / Q000601:surgery*; D055815:Young Adult
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