title: Optical coherence tomography versus intravascular ultrasound in the evaluation of observer variability and reliability in the assessment of stent deployment: the OCTIVUS study.
abstract: OBJECTIVE
  To compare the variability in the assessment of coronary stents among interventional cardiologists (readers) using optical coherence tomography (OCT) and intravascular ultrasound (IVUS).
  
  
  BACKGROUND
  IVUS is established and validated in the evaluation of coronary stent. For cardiologists without core lab expertise, the utility of IVUS is limited by image quality. OCT yields higher image resolution; however, the consistency with which these readers interpret OCT images has not been fully evaluated or compared with IVUS.
  
  
  METHODS
  OCT and IVUS image sets (five pairs) obtained after stent placement were reviewed by readers with clinical experience in both modalities. Parameters assessed included stent expansion and symmetry, reference vessel and in-stent cross-sectional area (CSA) and diameter, and stent strut apposition as well as Multicenter Ultrasound Stenting in Coronaries criteria. These interpretations were compared with core lab readings and examined for interobserver variability.
  
  
  RESULTS
  The interobserver variability for measurement of in-stent CSA was 1.34 mm(2) using IVUS compared with 0.85 mm(2) using OCT (P = 0.024). Variation in the deviation from core lab measurement of in-stent CSA for IVUS was 1.48 mm(2) compared with 0.87 mm(2) for OCT (P = 0.042). The interobserver agreement for obtaining the Multicenter Ultrasound Stenting in Coronaries criteria using IVUS was 80.4% compared with 81.1% using OCT (P = 0.78). Compared with the corelab measurement, the readers obtained an agreement of 72.7% using IVUS vs. 67.3% using OCT (P = 0.43).
  
  
  CONCLUSIONS
  In the assessment of deployed coronary stents by practicing cardiologists, OCT images are interpreted more consistently compared with IVUS and can be used to assess stent deployment using IVUS-validated metrics.
authors.affiliation: Cardiac Catheterization Laboratories, Heart and Vascular Center, Dartmouth-Hitchcock Medical Center/Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire.
authors.forename: Patrick C
authors.identifier: http://orcid.org/0000-0002-2041-939X
authors.initials: PC
authors.lastname: Magnus
authors.affiliation: Cardiac Catheterization Laboratories, Heart and Vascular Center, Dartmouth-Hitchcock Medical Center/Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire.
authors.forename: John E
authors.initials: JE
authors.lastname: Jayne
authors.affiliation: Cardialysis BV, Rotterdam, The Netherlands.
authors.forename: Hector M
authors.initials: HM
authors.lastname: Garcia-Garcia
authors.affiliation: Cardialysis BV, Rotterdam, The Netherlands.
authors.forename: Michael
authors.initials: M
authors.lastname: Swart
authors.affiliation: Cardialysis BV, Rotterdam, The Netherlands.
authors.forename: Gerrit-Anne
authors.initials: GA
authors.lastname: van Es
authors.affiliation: Cardialysis BV, Rotterdam, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Tijssen
authors.affiliation: Cardiac Catheterization Laboratories, Heart and Vascular Center, Dartmouth-Hitchcock Medical Center/Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire.
authors.forename: Aaron V
authors.initials: AV
authors.lastname: Kaplan
mesh_terms: D002983:Clinical Competence; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy*; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D015588:Observer Variation; D062645:Percutaneous Coronary Intervention / Q000295:instrumentation*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D015607:Stents; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional
keywords: MUSIC criteria; intravascular ultrasound; optical coherence tomography