title: Imaging of vulnerable atherosclerotic plaques with FDG-microPET: no FDG accumulation.
abstract: BACKGROUND
  Non-invasive methods of evaluating atherosclerosis in humans and experimental animals are needed. Studies indicate that FDG-PET has a potential to detect vulnerable, inflamed atherosclerotic lesions.
  
  
  METHODS
  Nine atherosclerotic apoE-deficient mice were PET scanned. Four to determine optimal timing for imaging, and five post mortem after 1h redistribution of FDG and again after sequential removal of the interscapular brown fat and the atherosclerotic aortic arch. Uptake in various tissues in fasting (n=13) and non-fasting (n=7) apoE-deficient mice, including atherosclerotic and non-atherosclerotic aorta, was measured. Finally, accelerated atherosclerosis was induced by carotid ligation (n=12), and FDG-uptake was measured.
  
  
  RESULTS
  FDG accumulation initially thought to correspond to the atherosclerotic aortic arch was recorded. Removal of interscapular brown fat, but not atherosclerotic aortic arch, removed the signal. The aortic arch accumulated less FDG than the non-atherosclerotic thoracic aorta both in fasting (ratio 0.5, p=0.008) and non-fasting (ratio 0.33, p=0.02) conditions. Carotid atherosclerosis likewise failed to increase FDG-uptake compared to the non-ligated artery (ratio 1.03).
  
  
  CONCLUSIONS
  Spontaneously developed advanced atherosclerotic lesions in aorta were, paradoxically, associated with reduced FDG uptake, and accelerated carotid atherosclerosis also failed to increase FDG-uptake. The results seriously question the potential of FDG-PET for imagining of advanced, vulnerable atherosclerotic lesions.
authors.affiliation: Department of Cardiology and Institute of Clinical Medicine, Aarhus University Hospital (Skejby), Aarhus, Denmark. jlaurberg@ki.au.dk <jlaurberg@ki.au.dk>
authors.forename: Jacob Marsvin
authors.initials: JM
authors.lastname: Laurberg
authors.forename: Aage Kristian
authors.initials: AK
authors.lastname: Olsen
authors.forename: Søren Baarsgaard
authors.initials: SB
authors.lastname: Hansen
authors.forename: Morten
authors.initials: M
authors.lastname: Bottcher
authors.forename: Matthew
authors.initials: M
authors.lastname: Morrison
authors.forename: Sally-Ann
authors.initials: SA
authors.lastname: Ricketts
authors.forename: Erling
authors.initials: E
authors.lastname: Falk
mesh_terms: D002001:Adipose Tissue, Brown / Q000000981:diagnostic imaging / Q000378:metabolism; D000818:Animals; D001011:Aorta / Q000000981:diagnostic imaging* / Q000378:metabolism; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging / Q000378:metabolism; D001057:Apolipoproteins E / Q000172:deficiency; D001161:Arteriosclerosis / Q000000981:diagnostic imaging*; D005215:Fasting; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics; D051379:Mice; D049268:Positron-Emission Tomography
chemical_list: D001057:Apolipoproteins E; D019788:Fluorodeoxyglucose F18