title: Optimal boundary detection method and window settings for coronary atherosclerotic plaque volume analysis in coronary computed tomography angiography: comparison with intravascular ultrasound.
abstract: OBJECTIVE
  To evaluate optimal methodology for quantitative plaque volume analysis by coronary CT angiography (QCT).
  
  
  METHODS
  Fifty-one coronary artery segments were evaluated and contour measurements based on two different methods [(1) no gap, or (2) fixed 0.3-mm gap between inner and outer boundary] were compared with intravascular ultrasound (IVUS). In addition, three different window width (WW) and level (WL) settings [fixed (740/220) Hounsfield unit (HU), adjusted (155 % and 65 % of mean luminal intensity of the segment, and aorta adjusted (155 % and 65 % of mean luminal intensity of central aorta)] were used for semiautomated plaque volume analysis.
  
  
  RESULTS
  For boundary detection, the no gap method led to underestimation compared with IVUS (105.4 ± 82.3 vs. 136.1 ± 72.8 mm(3), p < 0.001), while fixed 0.3-mm gap showed no difference between IVUS and QCT (136.1 ± 72.8 vs. 139.8 ± 93.9 mm(3), p = 0.50). Comparison of the three different window settings demonstrated that the aorta adjusted setting underestimated (120.5 ± 74.3 vs. 136.1 ± 72.8 mm(3), p = 0.003), while fixed setting showed the least mean difference compared with IVUS (3.8 ± 39.8 mm(3), p = 0.50).
  
  
  CONCLUSIONS
  For plaque volumetric assessment, optimal results were obtained with fixed 0.3-mm gap with fixed HU setting (740/220).
  
  
  CONCLUSIONS
  • Quantitative plaque volume analysis by coronary CT angiography has recently emerged. • Different boundary detection methods and window width and level settings were evaluated. • Fixed 0.3-mm gap with fixed HU setting (740/220) afforded optimal results.
authors.affiliation: Yonsei-Cedars Sinai Integrative Cardiovascular Imaging Research Center, Yonsei University Health System, Seoul, South Korea.|Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University Health System, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, South Korea.
authors.forename: Ran
authors.initials: R
authors.lastname: Heo
authors.affiliation: Yonsei-Cedars Sinai Integrative Cardiovascular Imaging Research Center, Yonsei University Health System, Seoul, South Korea.|Division of Cardiology, Cardiovascular Center, Myongji Hospital, Seonam University College of Medicine, Goyang, South Korea.
authors.forename: Hyung-Bok
authors.initials: HB
authors.lastname: Park
authors.affiliation: Division of Cardiology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Byoung Kwon
authors.initials: BK
authors.lastname: Lee
authors.affiliation: Yonsei-Cedars Sinai Integrative Cardiovascular Imaging Research Center, Yonsei University Health System, Seoul, South Korea.|Division of Cardiology, National Health Insurance Corporation Ilsan Hospital, Goyang, South Korea.
authors.forename: Sanghoon
authors.initials: S
authors.lastname: Shin
authors.affiliation: Departments of Imaging and Medicine, Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
authors.forename: Reza
authors.initials: R
authors.lastname: Arsanjani
authors.affiliation: Institute for Cardiovascular Imaging, Weill-Cornell Medical College, New York-Presbyterian Hospital, New York, NY, USA.
authors.forename: James K
authors.initials: JK
authors.lastname: Min
authors.affiliation: Yonsei-Cedars Sinai Integrative Cardiovascular Imaging Research Center, Yonsei University Health System, Seoul, South Korea. HJCHANG@yuhs.ac.|Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University Health System, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, South Korea. HJCHANG@yuhs.ac.
authors.forename: Hyuk-Jae
authors.initials: HJ
authors.lastname: Chang
mesh_terms: D000368:Aged; D000072226:Computed Tomography Angiography / Q000379:methods*; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000175:diagnosis*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000175:diagnosis*; D018084:Ultrasonography, Interventional / Q000379:methods*
keywords: Boundary detection; Coronary CT angiography; Intravascular ultrasound; Quantitative plaque volume analysis; Window settings