The physics of contrast microbubbles

The quantification of microvascular flow, often termed perfusion, using contrast enhanced ultrasound (CEUS) is being researched over 30 years. The material uses as contrast agents are microbubbles (MB) that are also researched for molecularly targeted imaging, enhancement of cell porosity, thrombolysis and drug/gene delivery.
Super-resolution Ultrasound (SRU) has emerged as a branch of CEUS in the last 5 years and presents an exciting prospect for diagnostic imaging altogether. This is because it enables the imaging of the vascular bed with near-microscopic quality. Central to this development is the knowledge we have achieved over the years on their physical understanding as well as the engineering that is used to deploy them as contrast agents. These topics will be reviewed in the light of their redeployment in SRU.