Understanding the Form of the Input pressure of Focused Ultrasound in the Rayleigh-Plesset Equation to Improve Drug Delivery Efficiency

To improve the drug delivery efficiency in the brain, the combination of the focused ultrasound (FUS) with microbubbles (MBs) shows a great potential to increase the permeability of the blood-brain barrier (BBB). The Rayleigh-Plesset equation is widely used to describe the dynamics of the MB, however, it is not clear what the most promising form of the FUS should be. In this manuscript, we investigate the choice of the input pressure of the FUS, both from analytical and numerical perspective. Furthermore, sensitivity tests are conducted to investigate the relations between the oscillation of the MB and the parameters. We conclude that the average of the FUS should lie at zero, since the MB must expand compared to its initial radius to release the drug molecules.