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Updated: Apr 5, 2026

Energy Dispersive X-ray Tomography for 3D Elemental Mapping of Individual Nanoparticles
Published on: July 5, 2016
Material Decomposition in Dual-Energy Computed Tomography Separates High-Z Elements From Iodine, Identifying
Tobias Fält1, Marcus Söderberg, Johan Wassélius
1From the Departments of *Radiology, and †Clinical Sciences, Medical Radiation Physics, Lund University, Skåne University Hospital, Malmö, Sweden.
Objective:
The aim of this study was to determine the potential of different high-Z elements to act as contrast media (CMs) alongside iodine (I) in dual-CM, dual-energy (DE) computed tomography examinations.
Methods:
Gadolinium (Gd), tantalum (Ta), wolfram (W), gold (Au), and bismuth (Bi) in addition to I were examined at all available kilovolt settings in a DE computed tomography scanner. Dual-energy ratios were calculated by dividing attenuation at low kilovolt by attenuation at high kilovolt. Dual-energy data sets were loaded into material decomposition software to evaluate separation of the elements from I.
Results:
The DE ratios of Ta, W, and Au ranged between 0.9 and 1.2, being considerably lower than I at 1.9 to 2.6. These elements were completely separated from I using material decomposition. Gadolinium and Bi were more similar to I at 1.4 to 1.9. However, separation was nearly complete for Bi and suboptimal for Gd.
Conclusions:
Tantalum, W, and Au are ideal candidates for dual-CM examinations, whereas Bi is a slightly weaker candidate.
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