title: Coronary plaque quantification by voxel analysis: dual-source MDCT angiography versus intravascular sonography.
abstract: OBJECTIVE
  The purpose of this study was to evaluate a voxel-based analytic technique for quantification of noncalcified coronary artery plaque with intravascular sonography as a standard of reference.
  
  
  METHODS
  Intravascular sonography and dual-source MDCT angiography prospectively performed on 12 patients resulted in identification of 20 segments containing noncalcified plaque. Four of these segments were used to establish reference measurements of 0.6-mm proximal wall thickness with a 0-HU cutoff between the epicardial fat and outer wall and an individually adjusted threshold for the interface between the wall and lumen. With these data, consecutive circular layers of the outer wall were subtracted from a 3D volume to determine the plaque plus medial layer and the actual plaque volume in the other 16 segments. Accuracy of the voxel technique was assessed by comparing the results with intravascular sonographic findings.
  
  
  RESULTS
  Both the total plaque burden (plaque plus medial layer) and the actual plaque volume had good concordance with intravascular sonographic findings (49.6 +/- 20 mm (3) vs 56.7 +/- 23.6 mm (3), p = 0.076; 26.5 +/- 14.8 mm (3) vs 30.9 +/- 15.3 mm (3), p = 0.09). Corresponding correlation coefficients were r = 0.76 and r = 0.79. The method had good reproducibility, the an intraclass correlation coefficients being 0.93 for total plaque burden and 0.90 for actual plaque volume.
  
  
  CONCLUSIONS
  Voxel analysis can be used for accurate and reproducible quantification not only of plaque burden but also of actual plaque volume.
authors.affiliation: Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Ave., WCC-302, Boston, MA 02215, USA.
authors.forename: Harald
authors.initials: H
authors.lastname: Brodoefel
authors.forename: Christof
authors.initials: C
authors.lastname: Burgstahler
authors.forename: Adeel
authors.initials: A
authors.lastname: Sabir
authors.forename: Chun-Shan
authors.initials: CS
authors.lastname: Yam
authors.forename: Faisal
authors.initials: F
authors.lastname: Khosa
authors.forename: Claus D
authors.initials: CD
authors.lastname: Claussen
authors.forename: Melvin E
authors.initials: ME
authors.lastname: Clouse
mesh_terms: D000368:Aged; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed; D018084:Ultrasonography, Interventional / Q000379:methods*
chemical_list: D003287:Contrast Media