Intravascular Targets for Molecular Contrast-Enhanced Ultrasound Imaging

Abstract

Molecular targeting of contrast agents for ultrasound imaging is emerging as a new medical imaging modality. It combines advances in ultrasound technology with principles of molecular imaging, thereby allowing non-invasive assessment of biological processes <em>in vivo</em>. Preclinical studies have shown that microbubbles, which provide contrast during ultrasound imaging, can be targeted to specific molecular markers. These microbubbles accumulate in tissue with target (over) expression, thereby significantly increasing the ultrasound signal. This concept offers safe and low-cost imaging with high spatial resolution and sensitivity. It is therefore considered to have great potential in cancer imaging, and early-phase clinical trials are ongoing. In this review, we summarize the current literature on targets that have been successfully imaged in preclinical models using molecularly targeted ultrasound contrast agents. Based on preclinical experience, we discuss the potential clinical utility of targeted microbubbles.

Keywords

• ultrasound imaging
• targeted contrast agents
• angiogenesis
• molecular imaging
• microbubbles
• cancer