The theoretical and experimental analysis of ultrasound contrast agent micro bubbles: The Sonovue

Sonovue is a kind of ultrasound contrast agent (UCA) with a stable shell made by lipid, within which is SF6. Due to the specific acoustic characteristics, UCA has been widely used in ultrasound diagnosis and therapy. In some cases, the 2nd harmonic wave of the scattered signal should be strong enough to help form a high quality image. To better utilize the bubbles to get enough intensity of the 2nd harmonic wave of the scattered signal, numerical simulation and corresponding experiments based on the several models proposed before have been analyzed to study the behavior of the bubbles. In this paper, we use the ratio of the second harmonic wave and fundamental wave to evaluate the oscillation of the bubbles. Besides, we have compared different simulation models and designed corresponding platform of phantom study. Finally, we find that the second harmonic wave will get a remarkable growth when the driving pressure is under 150KPa in the simulation or under 200KPa in the experiment.