title: Seizure freedom after functional hemispherectomy and a possible role for the insular cortex: the Dutch experience.
abstract: OBJECTIVE
  The authors undertook this study to identify predictors of persistent postoperative seizures in their group of 28 Dutch pediatric and adolescent patients with medically intractable epilepsy who underwent functional hemispherectomy.
  
  
  METHODS
  The records of 28 pediatric and adolescent patients who underwent a functional hemispherectomy in the University Medical Center Utrecht were retrospectively analyzed. The authors performed a Cox regression analysis, using the first postoperative seizure as the event. Pathology, age at surgery, age at seizure onset, duration of epilepsy, type of surgery, surgeon, possible incomplete disconnection on MR images, and presence of residual insular cortex were analyzed as potential associated variables during the follow-up period.
  
  
  RESULTS
  The patients' mean age at surgery was 69.9 months (range 3.0-294.2 months) and mean duration of follow-up was 39.0 months (range 6.0-132.0 months). Six patients had postoperative seizures (21%). One patient had persistent bilateral status epilepticus and died 4 months after surgery. The Cox regression analysis showed presence of insular cortex to be the only variable statistically associated with postoperative seizures (p = 0.021) in this group of 28 patients.
  
  
  CONCLUSIONS
  In this group of Dutch pediatric and adolescent patients, residual insular cortex was positively correlated with persistent postoperative seizures. Given the small sample size in this study, however, caution should be used in drawing conclusions about the role of the insular cortex.
authors.affiliation: Department of Neurology, Rudolf Magnus Center of Neuroscience, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands. e.cats@umcutrecht.nl
authors.forename: Elisabeth A
authors.initials: EA
authors.lastname: Cats
authors.forename: Kuan H
authors.initials: KH
authors.lastname: Kho
authors.forename: Onno
authors.initials: O
authors.lastname: Van Nieuwenhuizen
authors.forename: Cornelis W M
authors.initials: CW
authors.lastname: Van Veelen
authors.forename: Peter H
authors.initials: PH
authors.lastname: Gosselaar
authors.forename: Peter C
authors.initials: PC
authors.lastname: Van Rijen
mesh_terms: D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000627:therapeutic use; D002540:Cerebral Cortex / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography; D004827:Epilepsy / Q000188:drug therapy / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D038421:Hemispherectomy / Q000009:adverse effects*; D006801:Humans; D006849:Hydrocephalus / Q000209:etiology; D007223:Infant; D008297:Male; D016016:Proportional Hazards Models; D012086:Reoperation; D012189:Retrospective Studies; D012640:Seizures / Q000209:etiology* / Q000503:physiopathology* / Q000601:surgery; D013226:Status Epilepticus / Q000175:diagnosis / Q000209:etiology / Q000401:mortality / Q000601:surgery
chemical_list: D000927:Anticonvulsants