The Evaluation of Contrast-to-Noise Ratio in CT Images Using Different Parameters of Gold Nanoparticles versus Omnipaque

Purpose: Gold Nanoparticles (GNPs) with high density and an atomic number have lately been proposed as an alternative contrast agent for Computed Tomography (CT). Materials and Methods: In the present study, the Contrast-to-Noise Ratio (CNR) of GNPs from various shapes, sizes, concentrations, and surface chemistry was compared with an iodine contrast agent using CT at different X-ray tube voltages and concentrations. Results: Our findings showed that GNPs in various concentrations, shapes, sizes, and X-ray tube energies from 80 to 140 kVp revealed greater image CNR than iodinated contrast media (Omnipaque). Smaller spherical GNPs (13 nm) had greater CNR than larger ones (60 nm) and Gold Nanorods )GNRs( with a larger Aspect Ratio (AR) represented excellent effect on CNR. In addition, Polyethylene Glycol (PEG) covering on GNRs decreased CNR. We observed image CNR was increased using increasing in kVp and concentration. Conclusion: Smaller spherical GNPs can be proposed as a potential candidate as a future contrast agent alternative to iodinated contrast media.