Particle swarm optimization of the manipulation of acoustic waves through nonhomogeneous, anisotropic mediums for application in shock wave lithotripsy

Shock Wave Lithotripsy is the most widely used treatment for kidney stones, a fragmentation process using shock waves generated outside the body that are focused onto the stone. However, the nonhomogenous, anisotropic nature of the human body causes the waves to be refracted, which can lead to less efficient fracturing of the kidney stone, requiring longer or more frequent treatment sessions, and increased risks of side effects from treatment. In this paper, a Particle Swarm Optimization (PSO) algorithm was utilized to program wave generators using a swarm of individual particles representing element configurations, such as amplitude, phase difference, and stimulation parameters. A Finite Element Model of the area between the shockwave generator and the kidneys used to demonstrate how the PSO algorithm can efficiently optimize a multi-objective function that maximizes predictions of activation in the kidney stone (Region of Interest, ROI) and minimizes predictions of activation in the surrounding sensitive tissues (Regions of Avoidance, ROA).