Intravascular ultrasound-based imaging and drug delivery

An ideal solution for the diagnosis and treatment of a vascular disease must involve high-resolution imaging, quantitative characterization of the lesion, and the means to provide a comprehensive and versatile therapy that can be completed within a single catheterization procedure. Intravascular ultrasound (IVUS) provides real-time, radiation-free imaging and assessment of atherosclerotic disease in terms of anatomical, functional, and molecular information. In this paper we explore the potential of IVUS for diagnosis, therapy, and therapeutic monitoring. In addition, we propose to integrate microfluidic devices directly within a catheter to enable on-demand production of microbubbles for IVUS applications. We have demonstrated that 1) IVUS can perform molecular imaging; 2) IVUS imaging of in situ-produced microbubbles results in a 15 dB increase in lumen contrast; 3) IVUS acoustic radiation force in an ex vivo swine carotid artery model increases delivery of a model drug 17-fold; 4) in situ-produced microbubbles can deliver a model drug to cells under physiologically relevant flows; 5) IVUS in combination with microbubbles can successfully enhance gene delivery in vivo; and 6) IVUS can improve optical methods for estimating model drug delivery.