title: Measuring noncalcified coronary atherosclerotic plaque using voxel analysis with MDCT angiography: a pilot clinical study.
abstract: OBJECTIVE
  The purpose of our study was to evaluate a new method using voxel analysis for quantifying noncalcified plaque in coronary arteries using MDCT angiography (MDCTA) compared with luminal stenosis by catheter coronary arteriography.
  
  
  METHODS
  Forty-one normal and eight abnormal arterial cross sections with noncalcified plaque selected from 40 patients undergoing MDCTA were analyzed for percentage of stenosis and plaque volume using a voxel analysis technique.
  
  
  RESULTS
  Using voxel analysis, the normal arterial wall thickness was determined to be 0.8 +/- 0.4 mm. Attenuation values (in Hounsfield units) for normal segments ranged between 30 and 175 H and for abnormal (plaque-containing) segments ranged from -49 to 139 H (p < 0.05). Plaque volume measurements varied from 0.90 to 156 mm(3) with good interobserver correlation (R(2) = 0.9671). Percentage of stenosis correlated with quantitative coronary arteriography measurement (R(2) = 0.55). Voxel analysis underestimated the percentage of stenosis (Pearson's correlation coefficient, 1.2; p = 0.03).
  
  
  CONCLUSIONS
  The study shows that the voxel analysis technique appears to be an accurate and reproducible method to measure arterial wall thickness, noncalcified plaque, and degree of arterial stenosis using density values measured in Hounsfield units. The technique may be useful on further correlative studies.
authors.affiliation: Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., WCC-302, Boston, MA 02215, USA. mclouse@bidmc.harvard.edu
authors.forename: Melvin E
authors.initials: ME
authors.lastname: Clouse
authors.forename: Adeel
authors.initials: A
authors.lastname: Sabir
authors.forename: Chun-Shan
authors.initials: CS
authors.lastname: Yam
authors.forename: Norihiko
authors.initials: N
authors.lastname: Yoshimura
authors.forename: Shezhang
authors.initials: S
authors.lastname: Lin
authors.forename: Francine
authors.initials: F
authors.lastname: Welty
authors.forename: Pedro
authors.initials: P
authors.lastname: Martinez-Clark
authors.forename: Vassilios
authors.initials: V
authors.lastname: Raptopoulos
mesh_terms: D000465:Algorithms; D002114:Calcinosis / Q000000981:diagnostic imaging; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011856:Radiographic Image Enhancement / Q000379:methods; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*