title: Application of subhairline EEG montage in intensive care unit: comparison with full montage.
abstract: OBJECTIVE
  Problems with the availability of standard EEG monitoring in the intensive care unit have led to the use of recordings that have limited spatial coverage. We studied the performance of limited coverage EEG compared with more traditional full-montage EEG.
  
  
  METHODS
  Continuous EEG recordings were performed on 170 patients using the full-montage 10-20 placement of electrodes as a reference recording and an abbreviated montage of electrodes applied below the hairline (subhairline). Recordings were reviewed independently, with the identity of the patients concealed.
  
  
  RESULTS
  Seizures were found in 8% of patients. Sensitivity for detecting patients with seizures using the subhairline system was 0.54 [95% confidence interval (95% CI), 0.29-0.77] with specificity of 1.00 (95% CI, 0.97-1.00) and positive predictive value of 1.00 (95% CI, 0.65-1.00). For detecting interictal epileptiform activity, we found sensitivity to be 0.60 (95% CI, 0.46-0.74), specificity to be 0.94 (95% CI, 0.88-0.97), and positive predictive value to be 0.81 (95% CI, 0.65-0.91). Performance was poor for triphasic waves, alpha/theta/spindle coma, and suppression.
  
  
  CONCLUSIONS
  The subhairline montage shows excellent specificity for detecting patients with seizure activity but has limited sensitivity. It has relatively poor performance for other EEG phenomena, but further applications in trending and assessing reactivity should be assessed in further studies.
authors.affiliation: *GE Healthcare Finland Oy, Helsinki, Finland; and Departments of †Anesthesia and Perioperative Medicine, ‡Program in Critical Care, and §Clinical Neurological Science, of Western Ontario, London, Ontario, Canada.
authors.forename: Antti E J
authors.initials: AE
authors.lastname: Tanner
authors.forename: Mika O K
authors.initials: MO
authors.lastname: Särkelä
authors.forename: Juha
authors.initials: J
authors.lastname: Virtanen
authors.forename: Hanna E
authors.initials: HE
authors.lastname: Viertiö-Oja
authors.forename: Michael D
authors.initials: MD
authors.lastname: Sharpe
authors.forename: Loretta
authors.initials: L
authors.lastname: Norton
authors.forename: Corrine
authors.initials: C
authors.lastname: Davies-Schinkel
authors.forename: Gordon Bryan
authors.initials: GB
authors.lastname: Young
mesh_terms: D000328:Adult; D004569:Electroencephalography / Q000379:methods* / Q000592:standards; D006801:Humans; D007362:Intensive Care Units / Q000592:standards; D012640:Seizures / Q000175:diagnosis* / Q000503:physiopathology*