title: Evaluation of coronary arterial calcification - Ex-vivo assessment by optical frequency domain imaging.
abstract: OBJECTIVE
  The purpose of this study was to determine the diagnostic ability of optical frequency domain imaging (OFDI) to carry out quantitative and qualitative evaluation of coronary calcification in comparing with ex vivo human autopsy heart specimens.
  
  
  METHODS
  Analysis was carried out in 25 coronary artery specimen obtained from 16 cadavers that were imaged ex-vivo imaging by OFDI and intravascular ultrasound (IVUS). Of 235 cross-sections obtained for histologic evaluation, 149 were classified as showing calcified plaques, and in this group a comparison between histology versus co-registered images by OFDI and IVUS was performed.
  
  
  RESULTS
  Maximum thickness of calcification measured by OFDI was well correlated with histology (rs = 0.70, p < 0.0001) whereas IVUS was not useful for quantitative analysis because of the presence of acoustic shadows occurring behind calcifications. Furthermore qualitative evaluation could be carried out using OFDI, for calcifications with vague or invisible outer borders by OFDI had lipid contents (lipid pool or histologic necrotic core) more frequently as compared to those with a clear outer border (79% vs. 24%, p < 0.0001). We also found that calcified nodules, a well-recognized thrombogenic substrate, demonstrated atypical appearance in OFDI, showing irregular surfaces with high attenuation.
  
  
  CONCLUSIONS
  OFDI demonstrated a greater ability than IVUS to provide quantitative and qualitative evaluation of coronary arterial calcification. Precise recognition of calcified plaque morphology by OFDI may serve to determine the treatment strategy of patients having atherosclerotic coronary disease.
authors.affiliation: Tokai University School of Medicine, Kanagawa, 259-1193, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ijichi
authors.affiliation: Tokai University School of Medicine, Kanagawa, 259-1193, Japan. Electronic address: gnakazawa@tokai-u.jp.
authors.forename: Gaku
authors.initials: G
authors.lastname: Nakazawa
authors.affiliation: Tokai University School of Medicine, Kanagawa, 259-1193, Japan.
authors.forename: Sho
authors.initials: S
authors.lastname: Torii
authors.affiliation: Tokai University School of Medicine, Kanagawa, 259-1193, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Nakano
authors.affiliation: Tokai University School of Medicine, Kanagawa, 259-1193, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Yoshikawa
authors.affiliation: Iwate Medical University, Iwate, 020-8505, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Morino
authors.affiliation: Tokai University School of Medicine, Kanagawa, 259-1193, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ikari
mesh_terms: D000368:Aged; D050197:Atherosclerosis / Q000473:pathology; D001344:Autopsy; D002102:Cadaver; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000473:pathology; D003331:Coronary Vessels / Q000473:pathology; D005260:Female; D006321:Heart / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008055:Lipids / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D061848:Optical Imaging; D058226:Plaque, Atherosclerotic / Q000473:pathology; D041623:Tomography, Optical Coherence; D018084:Ultrasonography, Interventional; D061205:Vascular Calcification / Q000175:diagnosis* / Q000473:pathology
chemical_list: D008055:Lipids
keywords: Histology; Intracoronary imaging; Intravascular ultrasound; Optical frequency domain imaging