title: Prognostic value of electrocorticography findings during callosotomy in children with Lennox-Gastaut syndrome.
abstract: OBJECTIVE
  To analyze findings and acute changes in electrocorticograms (ECoGs) obtained during corpus callosotomy in order to identify any relationships with the postoperative outcome of seizure activity.
  
  
  METHODS
  We retrospectively analyzed ECoGs obtained during anterior callosotomy (4-6 cm) in 48 patients with Lennox-Gastaut syndrome (32 boys and 16 girls, age 1-20 years, mean age 7.6 years) who underwent surgery between July 1993 and November 1996 to correlate recording findings with postoperative seizure activity. At the time of analysis, all patients had been followed postoperatively for more than 4 years.
  
  
  RESULTS
  Of 48 patients, 31 (64.6%) had significant improvement in seizure control after surgery. In pre-excisional ECoGs, 38 (79.2%) of 48 patients had bisynchronous epileptiform discharges. Patients (23 of 33 patients, 69.7%) with significant blockage of bisynchronous discharges recorded during callosotomy achieved the best postoperative seizure outcomes, but the difference did not reach statistical significance (P>0.05).
  
  
  CONCLUSIONS
  Based on our experience, changes in ECoG during callosotomy do not predict postoperative seizure outcome. Insignificant blockage of bisynchronous epileptiform discharges in ECoGs during callosotomy does not predict a worse prognosis than that associated with significant intraoperative blockage.
authors.affiliation: Pediatric Epilepsy Surgery Group, Taipei Veterans General Hospital, National Yang-Ming University School of Medicine, Taipei, Taiwan.
authors.forename: Shang-Yeong
authors.initials: SY
authors.lastname: Kwan
authors.forename: Ji-Ho
authors.initials: JH
authors.lastname: Lin
authors.forename: Tai-Tong
authors.initials: TT
authors.lastname: Wong
authors.forename: Kai-Ping
authors.initials: KP
authors.lastname: Chang
authors.forename: Chun-Hing
authors.initials: CH
authors.lastname: Yiu
mesh_terms: D000293:Adolescent; D000328:Adult; D002540:Cerebral Cortex / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D003337:Corpus Callosum / Q000601:surgery*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D020190:Myoclonic Epilepsy, Juvenile / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D011184:Postoperative Period; D011379:Prognosis; D011612:Psychosurgery / Q000379:methods; D012189:Retrospective Studies; D012640:Seizures / Q000503:physiopathology; D016896:Treatment Outcome