title: Characterization of human atherosclerosis by optical coherence tomography.
abstract: BACKGROUND
  High-resolution visualization of atherosclerotic plaque morphology may be essential for identifying coronary plaques that cause acute coronary events. Optical coherence tomography (OCT) is an intravascular imaging modality capable of providing cross-sectional images of tissue with a resolution of 10 micro m. To date, OCT imaging has not been investigated in sufficient detail to assess its accuracy for characterizing atherosclerotic plaques. The aim of this study was to establish objective OCT image criteria for atherosclerotic plaque characterization in vitro.
  
  
  RESULTS
  OCT images of 357 (diseased) atherosclerotic arterial segments obtained at autopsy were correlated with histology. OCT image criteria for 3 types of plaque were formulated by analysis of a subset (n=50) of arterial segments. OCT images of fibrous plaques were characterized by homogeneous, signal-rich regions; fibrocalcific plaques by well-delineated, signal-poor regions with sharp borders; and lipid-rich plaques by signal-poor regions with diffuse borders. Independent validation of these criteria by 2 OCT readers for the remaining segments (n=307) demonstrated a sensitivity and specificity ranging from 71% to 79% and 97% to 98% for fibrous plaques, 95% to 96% and 97% for fibrocalcific plaques, and 90% to 94% and 90% to 92% for lipid-rich plaques, respectively (overall agreement, kappa=0.83 to 0.84). The interobserver and intraobserver reliabilities of OCT assessment were high (kappa values of 0.88 and 0.91, respectively).
  
  
  CONCLUSIONS
  Objective OCT criteria are highly sensitive and specific for characterizing different types of atherosclerotic plaques. These results represent an important step in validating this new intravascular imaging modality and will provide a basis for the interpretation of intracoronary OCT images obtained from patients.
authors.affiliation: Cardiology Division, Massachusetts General Hospital and Harvard Medical School, Boston 02114, USA.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yabushita
authors.forename: Brett E
authors.initials: BE
authors.lastname: Bouma
authors.forename: Stuart L
authors.initials: SL
authors.lastname: Houser
authors.forename: H Thomas
authors.initials: HT
authors.lastname: Aretz
authors.forename: Ik-Kyung
authors.initials: IK
authors.lastname: Jang
authors.forename: Kelly H
authors.initials: KH
authors.lastname: Schlendorf
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Kauffman
authors.forename: Milen
authors.initials: M
authors.lastname: Shishkov
authors.forename: Dong-Heon
authors.initials: DH
authors.lastname: Kang
authors.forename: Elkan F
authors.initials: EF
authors.lastname: Halpern
authors.forename: Guillermo J
authors.initials: GJ
authors.lastname: Tearney
mesh_terms: D000368:Aged; D019412:Anatomy, Cross-Sectional / Q000295:instrumentation / Q000379:methods; D001011:Aorta / Q000473:pathology; D001161:Arteriosclerosis / Q000145:classification* / Q000473:pathology*; D002102:Cadaver; D002114:Calcinosis / Q000473:pathology; D002339:Carotid Arteries / Q000473:pathology; D003331:Coronary Vessels / Q000473:pathology; D005260:Female; D006801:Humans; D007259:Infrared Rays; D008297:Male; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014054:Tomography / Q000295:instrumentation / Q000379:methods*; D017539:Tunica Intima / Q000473:pathology