title: Histopathological correlates of the napkin-ring sign plaque in coronary CT angiography.
abstract: OBJECTIVE
  The purpose of this study was to identify histologic characteristics of advanced coronary atherosclerotic plaques that are related with the detection of the napkin-ring sign (NRS) in coronary CT angiography (CCTA).
  
  
  METHODS
  CCTA was performed in 7 human donor hearts. Histological slicing and stainings were performed in 1 mm increments of each major coronary artery. Histology was co-registered with the CT-data and classified according to the modified AHA classification.
  
  
  RESULTS
  Advanced plaques (types IV-VI) were present in 139 (23%) of 611 cross sections. Of these 33 (24%) demonstrated an NRS in CCTA. NRS plaques were associated with greater non-core plaque area (median 10.2 vs. 6.4 mm(2), p < 0.01) and larger vessel area (median 17.1 vs. 13.0 mm(2), p < 0.01). The area of the necrotic/lipid core was larger in plaques with NRS (median 1.1 vs. 0.5 mm(2), p = 0.05). Angiogenesis tended to be more frequent in plaques with NRS (48% vs. 30%) whereas micro-calcifications tended to be more frequent in plaques without NRS (27% vs. 46%) (p = 0.06 and 0.07 respectively). In a multivariate analysis, necrotic/lipid core area (OR = 1.9), non-core plaque area (OR = 1.6), and total vessel area (OR = 0.9) independently predicted the appearance of the NRS in coronary CT angiography.
  
  
  CONCLUSIONS
  Delineation of NRS in CCTA is independently linked to the size of the necrotic/lipid core, the size of the non-core plaque and to the vessel area as measured in histology of advanced coronary atherosclerotic plaques.
authors: Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, 165 Cambridge Street, Boston, MA 02114, USA.
authors: Harald
authors: H
authors: Seifarth
authors: Christopher L
authors: CL
authors: Schlett
authors: Masataka
authors: M
authors: Nakano
authors: Fumiyuki
authors: F
authors: Otsuka
authors: Mihály
authors: M
authors: Károlyi
authors: Gary
authors: G
authors: Liew
authors: Pál
authors: P
authors: Maurovich-Horvat
authors: Hatem
authors: H
authors: Alkadhi
authors: Renu
authors: R
authors: Virmani
authors: Udo
authors: U
authors: Hoffmann
mesh_terms: D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000473:pathology; D003331:Coronary Vessels / Q000473:pathology; D006801:Humans; D009336:Necrosis / Q000473:pathology; D058226:Plaque, Atherosclerotic / Q000473:pathology*; D014057:Tomography, X-Ray Computed