Introduction of ultrasound microbubble technology aided tumor imaging and treatment

Microbubble ultrasound contrast agent which is highly echo-genic has many unique properties. Microbubbles can improve the sensitivity of the conventional ultrasound imaging; tissue permeability can be moderately increased by high-frequency ultrasonic cavitation, and hardly any damage is caused even at the high acoustic pressure. Microbubbles can carry drugs and release them under ultrasound mediated microbubble destruction. Meanwhile, Microbubbles increased vascular permeability while enhancing drugs deposition in tissue. Scientists have focused on the research of targeted microbubble contrast agent, e.g. carrying genetic drugs to the target tissue, mediating tumor cell apoptosis and blocking tumor cells metastasis. This article reviews the microbubble-specific imaging, for its principles and applications; ultrasound-aided drug delivery, and targeted imaging are also reviewed. All the applications though promising require further improvements for future clinical use.