The potential of spectral-CT for material decomposition with gold-nanoparticle and iodine contrast

Abstract

The objective of the this study was to demonstrate feasibility of using gold contrast-agent as a new contrast agent for spectral-computed tomography (CT) system and decompose the iodine and gold materials in the spectral-CT system using K-edge imaging technique. Recently, gold based nanoparticles contrast-agent has been introduced for vulnerable plaque imaging in CT system. The spectral-CT system equipped with Cadmium Zinc Telluride (CZT)-based photoncounting detector has energy-discrimination capabilities and high resolution image acquisition capabilities. We performed a simulation study using the Geant4 Application for Tomographic Emission (GATE) simulation. The CZT detector contained four CZT crystals and total detector length is 51.2 mm with 64 channel array. The results showed that the contrast-tonoise ratios of iodine and gold contrast-agent materials in energy window included K-edge energy of materials (33-49 keV for iodine, 66-81 keV for gold) were increased approximately 1.9 and 1.7 times higher than others. These results also show the possibility of potential of using two contrast-agents at a time to provide the various information of image such as plaque vulnerability assessment.