Monte Carlo Simulation on the Imaging Contrast Enhancement in Nanoparticle-enhanced Radiotherapy

This study focused on the imaging in radiotherapy by finding the relationship between the imaging contrast ratio and appropriate gold, iodine, iron oxide, silver, and platinum nanoparticle concentrations; the relationship between the imaging contrast ratio and different beam energies for the different nanoparticle concentrations; the relationship between the contrast ratio and various beam energies for gold nanoparticles; and the relationship between the contrast ratio and different thicknesses of the incident layer of the phantom including variety of gold nanoparticles (GNPs) concentration. Monte Carlo simulation was used to model the gold, iodine, iron oxide, silver, and platinum nanoparticle concentration which were infused within a heterogeneous phantom (50 cm x 50 cm x 10.5 cm) choosing different concentrations (3, 7, 18, 30, and 40 mg), and beams (100, 120, 130, and 140 kVp) correspondingly that were delivered into the phantom. The results showed obvious connection between the high concentration and having a high imaging contrast ratio, low energy and a high contrast ratio, small thickness, and a high contrast ratio. The superior nanoparticle obtained was GNP, the better concentration was 40 mg, the better beam energy was 100 kVp, and the better thickness was 0.5 cm. It is concluded that our study successfully proved that medical imaging contrast could be improved by increasing the contrast ratio using GNP as the finest choice to accomplish this improvement considering a high concentration, low beam energy, and a small thickness.