title: Tissue characterization of coronary plaques: comparison of integrated backscatter intravascular ultrasound with virtual histology intravascular ultrasound.
abstract: BACKGROUND
  Integrated backscatter (IB) intravascular ultrasound (IVUS) and IVUS Virtual Histology (VH) have been developed for tissue characterization, but have never been compared directly. The purpose of this study was to compare the overall agreement between IB-IVUS and IVUS-VH in the tissue characterization of plaques from the same coronary arterial cross-section.
  
  
  RESULTS
  Images were acquired from 46 coronary arteries from 25 cadavers. Of a total of 392 histology/IVUS image pairs, 152 pairs were diagnosed as Stary's type III, IV, Va, Vb and Vc, and compared for IB-IVUS, IVUS-VH and histology. In the qualitative comparison, the overall agreement between histological and IB-IVUS diagnoses was higher (kappa = 0.81, 95% confidence interval (CI): 0.74-0.89) than that of the IVUS-VH diagnoses (kappa = 0.66, 95%CI: 0.56-0.75). The % fibrosis area determined by IB-IVUS was significantly correlated with the relative area of fibrosis based on histology (r = 0.67, p < 0.001). In the quantitative comparison, the overall agreement between the histological and IB-IVUS diagnoses was higher (kappa = 0.83, 95% CI: 0.75-0.91) than that of the IVUS-VH diagnoses (kappa = 0.73, 95% CI: 0.63-0.83).
  
  
  CONCLUSIONS
  Based on histology as the gold standard, IB-IVUS provided higher diagnostic accuracy than IVUS-VH for tissue characterization of coronary plaques.
authors.affiliation: Regeneration & Advanced Medical Science, Gifu University Graduate School of Medicine, Gifu, Japan.
authors.forename: Munenori
authors.initials: M
authors.lastname: Okubo
authors.forename: Masanori
authors.initials: M
authors.lastname: Kawasaki
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Ishihara
authors.forename: Urara
authors.initials: U
authors.lastname: Takeyama
authors.forename: Shinji
authors.initials: S
authors.lastname: Yasuda
authors.forename: Tomoki
authors.initials: T
authors.lastname: Kubota
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Tanaka
authors.forename: Takahiko
authors.initials: T
authors.lastname: Yamaki
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Ojio
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Nishigaki
authors.forename: Genzou
authors.initials: G
authors.lastname: Takemura
authors.forename: Masanao
authors.initials: M
authors.lastname: Saio
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Takami
authors.forename: Hisayoshi
authors.initials: H
authors.lastname: Fujiwara
authors.forename: Shinya
authors.initials: S
authors.lastname: Minatoguchi