title: Bipolar electrocoagulation on cortex after AVMs lesionectomy for seizure control.
abstract: BACKGROUND
  The findings of previous studies remain controversial on the optimal management required for effective seizure control after surgical excision of arteriovenous malformations (AVMs). We evaluated the efficacy of additional bipolar electrocoagulation on the electrically positive cortex guided by intraoperative electrocorticography (ECoG) for controlling cerebral AVMs-related epilepsy.
  
  
  METHODS
  Sixty consecutive patients with seizure due to cerebral AVMs, who underwent surgical excision of cerebral AVMs and intraoperative ECoG, were assessed. The AVMs and surrounding hemosiderin stained tissue were completely removed, and bipolar electrocoagulation was applied on the surrounding cerebral cortex where epileptic discharges were monitored via intraoperative ECoG. Patients were followed up at three to six months after the surgery and then annually. We evaluated seizure outcome by using Engel's classification and postoperative complications.
  
  
  RESULTS
  Forty-nine patients (81.6%) were detected of epileptic discharges before and after AVMs excision. These patients underwent the removal of AVMs plus bipolar electrocoagulation on spike-positive site cortex. After electrocoagulation, 45 patients' epileptic discharges disappeared, while four obviously diminished. Fifty-five of 60 patients (91.7%) had follow-up lasting at least 22 months (mean 51.1 months; range 22-93 months). Determined by the Engel Seizure Outcome Scale, 39 patients (70.9%) were Class I, seven (12.7%) Class II, five (9.0%) Class III, and four (7.2%) Class IV.
  
  
  CONCLUSIONS
  Even after the complete removal of AVM and surrounding gliotic and hemosiderin stained tissue, a high-frequency residual spike remained on the surrounding cerebral cortex. Effective surgical seizure control can be achieved by carrying out additional bipolar electrocoagulation on the cortex guided by the intraoperative ECoG.
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Cao
authors.forename: Rong
authors.initials: R
authors.lastname: Wang
authors.forename: Lijun
authors.initials: L
authors.lastname: Yang
authors.forename: Qin
authors.initials: Q
authors.lastname: Bai
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
authors.forename: Jizong
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001165:Arteriovenous Malformations / Q000150:complications / Q000601:surgery; D002540:Cerebral Cortex / Q000502:physiology* / Q000601:surgery*; D002648:Child; D004564:Electrocoagulation / Q000379:methods*; D004569:Electroencephalography / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012640:Seizures / Q000209:etiology / Q000473:pathology* / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult