SU-GG-I-157: Quantification of Radiographic Image Contrast Enhancement Using Gold Nanoparticles

Abstract

Purpose: To quantify radiologic imagecontrast enhancement using goldnanoparticles compared to iodinated contrast media (CM) over the entire diagnostic range of x‐ray energies. Method and Materials: A Perspex phantom with 4mm cylindrical wells was used to simulate small portions of vasculature. Each well was loaded with either goldnanoparticle solution or iodinated CM at equal concentration (0.5077 M radiopaque element). The phantom was imaged under full scatter conditions in computed radiography(CR) (40–80 kVp) and computed tomography(CT) (80–140 kVp). Images obtained at low energies (≈ 40 kVp) were validated using diagnostic type gafchromic film (Gafchromic® XRQA). CdTedetector with MCA was used to obtain transmission spectra after x‐ray beam at 130 kVp passed through solutions of goldnanoparticles or iodinated CM. Results:CT and CRimages were evaluated for contrast enhancement by contrast‐to‐noise ratio (CNR). Low energy results support previous findings, with gold exhibiting a 60% greater CNR than iodine. Goldnanoparticles also displayed excellent imagecontrast in CT, producing over two times greater signal than iodinated CM at 140 kVp. Over the x‐ray energy range of 70–100 kVp, however, both samples displayed similar contrast values. CdTe attenuation spectra are in accordance with image results where goldnanoparticles show a greater probability of attenuation than iodine for photons below approximately 35 keV and above 80 keV. Conclusion: Data indicates that a solution bearing goldnanoparticles would be an effective alternative to iodinated CM diagnostic radiology particularly at lower and higher ends of x‐ray energies used in radiology, such as mammography and CT.Conflict of Interest (only if applicable): Funding provided by NanoVic (Nanotechnology Victoria, Ltc.)