title: CT-based analysis of pericoronary adipose tissue density: Relation to cardiovascular risk factors and epicardial adipose tissue volume.
abstract: BACKGROUND
  Pericoronary adipose tissue (PCAT) can promote atherosclerosis. Metabolically active and inactive PCAT may display different CT densities. However, CT density could be influenced by partial volume effects and image interpolation.
  
  
  OBJECTIVE
  To investigate whether PCAT density values in CT displays differences that are larger than those attributable to interpolation and partial volume effects, which would manifest themselves through the relationship between PCAT density and distance from the contrast-enhanced coronary lumen.
  
  
  METHODS
  PCAT density analysis was performed (417 non-atherosclerotic segments, 63 patients) using dual-source CT with a threshold-based measurement method. Changes in PCAT density values depending on distance from the contrast-enhanced coronary lumen and the influence of cardiovascular risk profile were analyzed.
  
  
  RESULTS
  Mean PCAT density was -78.1 ± 5.6 HU. PCAT density decreased from proximal to distal segments in the LAD (-78.0 ± 7.3 vs. -82.4 ± 7.7 HU; p < 0.001). PCAT density was higher close to the lumen compared to more peripheral locations (-76.0 ± 6.7 vs. -78.5 ± 5.4 HU; p < 0.001). Decreasing PCAT density was significantly associated with higher epicardial adipose tissue (EAT) volume and body mass index. There was a trend of lower PCAT values with a family history of coronary artery disease.
  
  
  CONCLUSIONS
  CT-measured attenuation of PCAT is influenced by EAT volume and body mass index. A decrease of PCAT attenuation with increasing distance from the vessel and from proximal to distal segments may suggest variations in CT density of PCAT due to partial volume effects and image interpolation rather than solely due to differences in tissue composition or metabolic activity.
authors.affiliation: Department of Cardiology, University of Erlangen, Ulmenweg 18, 91054 Erlangen, Germany. Electronic address: michaela.hell@uk-erlangen.de.
authors.forename: Michaela M
authors.initials: MM
authors.lastname: Hell
authors.affiliation: Department of Cardiology, University of Erlangen, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Achenbach
authors.affiliation: Department of Cardiology, University of Erlangen, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Annika
authors.initials: A
authors.lastname: Schuhbaeck
authors.affiliation: Department of Cardiology, University of Erlangen, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Lutz
authors.initials: L
authors.lastname: Klinghammer
authors.affiliation: Department of Radiology, University of Erlangen, Maximiliansplatz 1, 91054 Erlangen, Germany.
authors.forename: Matthias S
authors.initials: MS
authors.lastname: May
authors.affiliation: Department of Cardiology, University of Erlangen, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Marwan
mesh_terms: D015502:Absorptiometry, Photon / Q000706:statistics & numerical data; D000273:Adipose Tissue / Q000000981:diagnostic imaging*; D050154:Adiposity; D017023:Coronary Angiography / Q000706:statistics & numerical data*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010496:Pericardium / Q000000981:diagnostic imaging*; D015995:Prevalence; D015203:Reproducibility of Results; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000706:statistics & numerical data*
keywords: Cardiovascular risk factors; Coronary computed tomography; Epicardial adipose tissue; Pericoronary adipose tissue; Tissue attenuation