April M. Chow1,2, Kannie W.Y. Chan1,2, Ed X. Wu1,2
1Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; 2Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
Gas-filled microbubbles have been shown as an MR susceptibility contrast agent; however, microbubble susceptibility effect is relatively weak when compared with other contrast agents. Studies have indicated that, by embedding magnetic nanoparticles, the magnetic susceptibility of the shell can be increased, thus enhancing the microbubble susceptibility effect. In this study, we further demonstrated the synergistic effect of gas core with iron oxide nanoparticles in achieving the overall microbubble susceptibility effect and characterized in vivo enhancements of microbubble susceptibility effects by entrapping iron oxide nanoparticles at 7 T, leading to the practical use of microbubbles as an intravascular MRI contrast agent.