Highlights
- •This paper uses material (plaque) specific and machine independent parameters.
- •Result of DECT was compared with pathology to assess their differentiating capability.
- •EDS revealed significant compositional difference in vulnerable and stable plaque.
- •Final study group consisted of total 32 non-calcified plaque samples.
Abstract
Purpose
In this study non-calcified plaque composition is evaluated by Dual Energy CT (DECT).
Energy Dispersive X-ray Spectroscopy (EDS) has been used to study the Plaque composition.
An attempt has been made to explain the DECT results with EDS analysis.
Methods
Thirty-two ex-vivo human cadaver coronary artery samples were scanned by DECT and
data was evaluated to calculate their effective atomic number and electron density
(Zeff & ρe) by inversion method. Result of DECT was compared with pathology to assess their
differentiating capability. The EDS study was used to explain DECT outcome.
Results
DECT study was able to differentiate vulnerable plaque from stable with 87% accuracy
(area under the curve (AUC):0.85 [95% confidence interval {CI}:0.73–0.98}] and Kappa
Coefficient (KC):0.75 with respect to pathology. EDS revealed significant compositional
difference in vulnerable and stable plaque at p < .05. The weight percentage of higher
atomic number elements like F, Na, Mg, S, Si, P, Cl, K and Ca was found to be slightly
more in vulnerable plaques as compared to a stable plaque. EDS also revealed a significantly
increased weight percentage of nitrogen in stable plaques.
Conclusions
The EDS results were able to explain the outcomes of DECT study. This study conclusively
explains the physics of DECT as a tool to assess the nature of non-calcified plaques
as vulnerable and stable. The method proposed in this study allows for differentiation
between vulnerable and stable plaque using DECT.
Keywords
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Article info
Publication history
Accepted:
December 4,
2017
Received in revised form:
December 3,
2017
Received:
March 31,
2017
Identification
Copyright
© 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
