title: Left dominance of EEG abnormalities in patients with transient global amnesia.
abstract: OBJECTIVE
  Transient global amnesia (TGA) is a syndrome of unknown etiology. Electroencephalographic (EEG) abnormalities in TGA have been reported previously. We analyzed the frequency and characteristics of EEG abnormalities in patients with TGA.
  
  
  METHODS
  We collected EEGs of patients with a clinical diagnosis of TGA who had visited the emergency room or the outpatient clinic over a period of 8 years and compared clinical and demographic characteristics of the patients with normal EEGs with those with abnormal EEGs.
  
  
  RESULTS
  EEG abnormalities were found in 35 (22.9%) out of 153 patients and epileptiform discharges were seen in 26 (74.3%) out of these 35 patients. Spikes or sharp waves were detected on the left side only (48.6%) or on both sides (25.7%), but none of the patients showed spikes or sharp waves on right side only. In six patients the EEG had normalized within three months of presentation, in ten within six months, and in twelve by one year. The EEG remained abnormal in eleven out of the 23 patients one year after presentation.
  
  
  CONCLUSIONS
  In this largest consecutive EEG study at one center, the proportion of patients with TGA in whom epileptiform discharges were demonstrated within days of the episode of TGA was significantly higher than in the previous literature. EEG abnormalities such as spikes or sharp waves spontaneously disappeared in almost half of cases over one-year of follow-up. There was a clear left dominance of EEG abnormalities in patients with TGA.
authors.affiliation: Department of Neurology, Seoul National University Bundang Hospital & Seoul National University College of Medicine, Republic of Korea.
authors.forename: YooSeok
authors.initials: Y
authors.lastname: Kwon
authors.affiliation: Department of Neurology, Veterans Hospital, Seoul Medical Center, Republic of Korea.
authors.forename: YoungSoon
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Neurology, College of Medicine, Kangwon National University, Republic of Korea.
authors.forename: Jae-Won
authors.initials: JW
authors.lastname: Jang
authors.affiliation: Department of Neurology, Seoul National University Bundang Hospital & Seoul National University College of Medicine, Republic of Korea.
authors.forename: Young Ho
authors.initials: YH
authors.lastname: Park
authors.affiliation: Department of Neurology, Seoul National University Bundang Hospital & Seoul National University College of Medicine, Republic of Korea.
authors.forename: JungEun
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Neurology, Seoul National University Bundang Hospital & Seoul National University College of Medicine, Republic of Korea.
authors.forename: Seong-Ho
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Neurology, Seoul National University Bundang Hospital & Seoul National University College of Medicine, Republic of Korea. Electronic address: neuroksy@snu.ac.kr.
authors.forename: SangYun
authors.initials: S
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020236:Amnesia, Transient Global / Q000175:diagnosis / Q000503:physiopathology*; D001921:Brain / Q000473:pathology* / Q000503:physiopathology*; D004569:Electroencephalography / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
keywords: EEG; Left dominance; Transient global amnesia