European Radiology

, Volume 23, Issue 2, pp 367–374 | Cite as

Changes in measured size of atherosclerotic plaque calcifications in dual-energy CT of ex vivo carotid endarterectomy specimens: effect of monochromatic keV image reconstructions

  • Lorenzo MannelliEmail author
  • Lee M. Mitsumori
  • Marina Ferguson
  • Dongxiang Xu
  • Baocheng Chu
  • Kelley R. Branch
  • William P. Shuman
  • Chun Yuan
Computed Tomography



The aim of this study was to compare the size of the calcifications measured on the different keV images to a histological standard.


Five ex vivo carotid endarterectomy (CEA) specimens were imaged with a dual-energy CT. CT images were reconstructed at different monochromatic spectral energies (40, 60, 77, 80, 100, 120, 140 keV). Cross-sectional area of the plaque calcifications present on each CT image was measured. The histological calcium areas on each corresponding CEA specimen were traced manually on digitised images of Toluidine Blue/Basic Fuchsin stained plastic sections. The CT images and corresponding histology sections were matched. The CT-derived calcium areas on each keV image were compared to the calcified area measurements by histology.


A total of 107 histology sections were matched to corresponding CT images. The average calcified area per section by histology was 7.6 ± 7 mm2 (range 0–26.4 mm2). There was no significant difference between the calcified areas measured by histology and those measured on CT–virtual monochromatic spectral (VMS) reconstructed images at 77 keV (P = 0.08), 80 keV (P = 0.20) and 100 keV (P = 0.14).


Calcium area measured on the 80 keV image set was most comparable to the amount of calcium measured by histology.

Key Points

Dual-energy computed tomography allows reconstruction of virtual monochromatic images.

Virtual monochromatic images reconstructed at different keVs reveal different atherosclerotic calcification quantification.

Virtual monochromatic images allows better evaluation of calcified atherosclerotic plaques.


Dual energy Computed tomography Carotid artery Calcification Monochromatic keV 



Preliminary data were presented at RSNA 2011.


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Copyright information

© European Society of Radiology 2012

Authors and Affiliations

  • Lorenzo Mannelli
    • 1
    • 2
    Email author
  • Lee M. Mitsumori
    • 1
  • Marina Ferguson
    • 1
  • Dongxiang Xu
    • 1
  • Baocheng Chu
    • 1
  • Kelley R. Branch
    • 1
  • William P. Shuman
    • 1
  • Chun Yuan
    • 1
  1. 1.Departments of RadiologyUniversity of WashingtonSeattleUSA
  2. 2.Department of Radiology, University of Washington Medical CenterUniversity of WashingtonSeattleUSA

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