Development and New Clinical Applications of Ultrasound Microbubble Contrast Agents / 中国医学物理学杂志

ABSTRACT

Objective: Several generations of ultrasound contrast agents have been developed. Now the application of targeted microbubble is an important research field. Methods: Ultrasound microbubble contrast agents can be divided into two types ordinary and special ones. First generation microbubble products are air bubbles. They lack a stabilizing shell and have large size. The second ones are stabilized by a sheU and have a smaller size ,instable gas cores consisting of air. The third ones have a stable shell and gas cores with perfiuorocarbons. Researches on new applications of targeted microbubble involve the targeted molecular imaging such as thrombus and inflammation imaging, thrombolytic therapy, drug/gene therapy and so on. Results: The stability of microbubble is increased gradually. Microbubble is injected intravenously and reaches the targeted tissue. At low ultrasound beam power imaging contrast can be improved. Low frequency ultrasound (1 MHz) can cause transient perfora-tion of cell membrane by cavitation effects and thereby improve drug/gene delivery efficiency. Conclusions: Ultrasound-target-ed microbubble has shown its advantages over other methods in the clinical diagnosis and treatment. While the bio-effects are not fully understood. And physical parameters affecting drug or gene delivery efficiency should be optimized.