title: Blood oxygen level-dependent magnetic resonance imaging of the human liver: preliminary results.
abstract: OBJECTIVE
  To investigate blood oxygen level-dependent (BOLD) response of human liver to hyperoxic exposure under fasting and postprandial conditions.
  
  
  METHODS
  Twelve healthy volunteers and 1 patient with chronic liver disease underwent liver BOLD magnetic resonance imaging at 3.0T. The BOLD images of a single slice were collected (1 image per second) during 3 breathing cycles of hyperoxia (3 minutes, 100% oxygen) with 5 minutes medical air (20.8% oxygen) in both preprandial and postprandial states. The BOLD signal time courses were correlated with a predefined stimulus paradigm.
  
  
  RESULTS
  Eight healthy subjects showed increased BOLD signal within 44.6% +/- 21.1% liver area in the fasting state with gas cycling. Two showed slightly reduced BOLD signal within 23.4% +/- 14.9% liver area in the fasting state with gas cycling. In the postprandial state, the degree of change in BOLD signal with gas cycling was reduced for both the subjects having increased and those having decreased signal with gas cycling (13.4% +/- 12.6% positive, 10.9% +/- 10.1% negative; P < 0.05). Chronic liver disease also demonstrated increased BOLD signal with gas cycling, but the correlation decreased postprandially.
  
  
  CONCLUSIONS
  The proposed physiological challenges induce certain BOLD signal response patterns in healthy and diseased livers, which may be useful for assessing liver function.
authors.affiliation: Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Zhaoyang
authors.initials: Z
authors.lastname: Fan
authors.forename: Alyaa
authors.initials: A
authors.lastname: Elzibak
authors.forename: Colm
authors.initials: C
authors.lastname: Boylan
authors.forename: Michael D
authors.initials: MD
authors.lastname: Noseworthy
mesh_terms: D000328:Adult; D003287:Contrast Media / Q000008:administration & dosage; D005215:Fasting / Q000502:physiology*; D006801:Humans; D018496:Hyperoxia / Q000378:metabolism; D007089:Image Enhancement / Q000379:methods; D008099:Liver / Q000098:blood supply / Q000378:metabolism*; D008107:Liver Diseases / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D010100:Oxygen / Q000097:blood*; D019518:Postprandial Period / Q000502:physiology*; D012016:Reference Values
chemical_list: D003287:Contrast Media; D010100:Oxygen