Competing Effect of Jetting During Microbubble-Mediated Sonothrombolysis

Sonothrombolysis is a technique that uses ultrasound and microbubbles to break down the clot. Despite its potential, it remains challenging to identify the right combination of ultrasound and microbubble properties that can lead to the best treatment of clots. To address this, a finite element model of a microbubble surrounded by blood and is next to a clot was developed to investigate the jetting behaviour of microbubbles using different combinations of microbubble radius and ultrasound pressure. Numerical results indicated a strong competing effect between jet velocity, jet width, and distance travelled by the bubble, which is likely due to the confining effect of clot. This effect can be detrimental to sonothrombolysis, especially when using smaller microbubbles. In addition, a higher ultrasound pressure was found to affect the jetting behaviour in a similar way as using a larger microbubble. The ability of the model to visualize the bubble behaviour in the fast temporal and the small spatial scale opens numerous opportunities for the optimisation and clinical translation of sonothrombolysis.