The UKAN Computational Acoustics Special Interest Group are pleased to welcome Nick Ovenden (UCL) who will present a talk on “Modelling the behaviour of microbubble contrast agents in biomedical applications” (details below). This talk will take place on Zoom.
Abstract
Gas microbubbles stabilised by a surfactant or polymer coating have been in clinical use as contrast agents for ultrasound imaging now for several decades. They are widely used in echocardiography and, increasingly, for quantitative studies of tissue perfusion. It is the highly nonlinear response of microbubbles to ultrasound excitation that makes them such effective contrast agents. It is this property also, however, that leads to significantly nonlinear propagation through regions of tissue containing microbubbles and both to image artefacts and difficulties in obtaining accurate quantitative information. Moreover, effects including abrupt changes in microbubble behaviour following repeated ultrasound excitation require further understanding. This talk will focus on two important aspects of modelling microbubble contrast agents: (i)reducing the computational complexity that arises in quantitative imaging algorithms of ultrasound propagation through a medium containing a polydisperse bubble population; (ii) modelling the behaviour of gas exchange and changes in the structure and properties of the bubble coating under repeated ultrasound excitation, which provides insight into microbubble shrinkage and surfactant shedding observed in experiments.