title: Relationship between thin cap fibroatheroma identified by virtual histology and angioscopic yellow plaque in quantitative analysis with colorimetry.
abstract: BACKGROUND
  Thin cap fibroatheroma (TCFA) is considered to be a vulnerable plaque. Virtual Histology-intravascular ultrasound (VH-IVUS) can precisely identify TCFA in vivo. Intense yellow plaque on angioscopy determined by quantitative colorimetry with L a b color space corresponds with histological TCFA; in particular, a plaque of color b value >23 indicates an atheroma with a fibrous cap thickness <100 mum. In the present study, the relationship between VH-TCFA and angioscopic plaque color determined by colorimetry was investigated.
  
  
  RESULTS
  Fifty-seven culprit plaques in 57 patients were evaluated by VH-IVUS and angioscopy. VH-TCFA was defined as a plaque with a necrotic core >10% of plaque area without overlying fibrous tissue, and angioscopic TCFA was a plaque with b value >23. The frequency of angioscopic TCFA was higher in the VH-TCFA group than in the VH-non-TCFA group (74% vs 23%, P=0.0002). Moreover, yellow color intensity (b value) significantly correlated with plaque classification on VH-IVUS. When TCFA detected with angioscopy was used as the gold standard, the sensitivity, specificity, and accuracy for TCFA with VH-IVUS was 68%, 81%, and 75%, respectively.
  
  
  CONCLUSIONS
  VH-TCFA strongly correlated with angioscopic TCFA determined by a quantitative analysis with colorimetry.
authors.affiliation: Department of Internal Medicine, Chiba-Hokusoh Hospital, Nippon Medical School, Chiba, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Masamichi
authors.initials: M
authors.lastname: Takano
authors.forename: Kentaro
authors.initials: K
authors.lastname: Okamatsu
authors.forename: Daisuke
authors.initials: D
authors.lastname: Murakami
authors.forename: Shigenobu
authors.initials: S
authors.lastname: Inami
authors.forename: Yong
authors.initials: Y
authors.lastname: Xie
authors.forename: Koji
authors.initials: K
authors.lastname: Seimiya
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ohba
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Seino
authors.forename: Kyoichi
authors.initials: K
authors.lastname: Mizuno
mesh_terms: D000368:Aged; D017546:Angioscopy / Q000379:methods / Q000592:standards*; D050197:Atherosclerosis / Q000145:classification / Q000000981:diagnostic imaging* / Q000473:pathology*; D003116:Color; D003124:Colorimetry / Q000295:instrumentation / Q000379:methods / Q000592:standards; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009336:Necrosis; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018084:Ultrasonography, Interventional / Q000379:methods / Q000592:standards*