title: Ammonia-related changes in cerebral electrogenesis in healthy subjects and patients with cirrhosis.
abstract: OBJECTIVE
  To study the effect of hyperammonaemia on the wake electroencephalogram (EEG) of patients with cirrhosis and healthy volunteers.
  
  
  METHODS
  Wake EEGs were recorded prior to and after the induction of controlled hyperammonaemia in 10 patients with cirrhosis and 10 matched healthy volunteers.
  
  
  RESULTS
  At baseline, patients had higher ammonaemia than healthy volunteers and their dominant EEG rhythm was slower and of higher amplitude. Induced hyperammonaemia resulted in increased spectral power over most of the scalp in healthy volunteers and decreased frequency along the anterior-posterior midline in patients.
  
  
  CONCLUSIONS
  These findings suggest different effects of hyperammonaemia on the wake EEG in relation to baseline/peak ammonia levels.
  
  
  CONCLUSIONS
  The wake EEG is sensitive to hyperammonaemia and power-based EEG parameters may help in its neurophysiological definition, which, to date, has generally been based on EEG frequency indices.
authors.affiliation: Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Bersagliere
authors.forename: I D
authors.initials: ID
authors.lastname: Raduazzo
authors.forename: S
authors.initials: S
authors.lastname: Schiff
authors.forename: A
authors.initials: A
authors.lastname: Gatta
authors.forename: C
authors.initials: C
authors.lastname: Merkel
authors.forename: P
authors.initials: P
authors.lastname: Amodio
authors.forename: P
authors.initials: P
authors.lastname: Achermann
authors.forename: S
authors.initials: S
authors.lastname: Montagnese
mesh_terms: D000328:Adult; D000368:Aged; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D006501:Hepatic Encephalopathy / Q000503:physiopathology*; D006801:Humans; D022124:Hyperammonemia / Q000503:physiopathology*; D008103:Liver Cirrhosis / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged