title: High-frequency Oscillations and the Seizure Onset Zones in Neocortical Epilepsy.
abstract: BACKGROUND
  To study the characters of high-frequency oscillations (HFOs) in the seizure onset zones (SOZ) and the nonseizure onset zones (NSOZ) in the electrocorticography (ECoG) of patients with neocortical epilepsy.
  
  
  METHODS
  Only patients with neocortical epilepsy who were seizure-free after surgery as determined with ECoG were included. We selected patients with normal magnetic resonance imaging before surgery in order to avoid the influence of HFOs by other lesions. Three minutes preictal and 10 min interictal ECoG as recorded in 39 channels in the SOZ and 256 channels in the NSOZ were analyzed. Ripples and fast ripples (FRs) were analyzed by Advanced Source Analysis software (ASA, The Netherlands). Average duration of HFOs was analyzed in SOZ and NSOZ separately.
  
  
  RESULTS
  For ripples, the permillage time occupied by HFOs was 0.83 in NSOZ and 1.17 in SOZ during the interictal period. During preictal period, they were 2.02 in NSOZ and 7.93 in SOZ. For FRs, the permillage time occupied by HFOs was 0.02 in NSOZ and 0.42 in SOZ during the interictal period. During preictal period, they were 0.03 in NSOZ and 2 in SOZ.
  
  
  CONCLUSIONS
  High-frequency oscillations are linked to SOZ in neocortical epilepsy. Our study demonstrates the prevalent occurrence of HFOs in SOZ. More and more burst of HFOs, especially FRs, means the onset of seizures.
authors.forename: Yan-Ping
authors.initials: YP
authors.lastname: Sun
authors.affiliation: Department of Neurology, Xuanwu Hospital, Capital Medical University; Beijing Key Laboratory of Neuromodulation, Beijing 100053, China.
authors.forename: Yu-Ping
authors.initials: YP
authors.lastname: Wang
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Wang
authors.forename: Feng-Yu
authors.initials: FY
authors.lastname: Wu
authors.forename: Li-Ou
authors.initials: LO
authors.lastname: Tang
authors.forename: Shou-Wen
authors.initials: SW
authors.lastname: Zhang
authors.forename: Hai-Tao
authors.initials: HT
authors.lastname: Pei
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Zhao-Yang
authors.initials: ZY
authors.lastname: Huang
authors.forename: Qing
authors.initials: Q
authors.lastname: Xue
authors.forename: Cui-Ping
authors.initials: CP
authors.lastname: Xu
authors.forename: Jun-Li
authors.initials: JL
authors.lastname: Tai
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D000069280:Electrocorticography; D004569:Electroencephalography; D004827:Epilepsy / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D012640:Seizures / Q000503:physiopathology*; D055815:Young Adult