Characterizing Ultrasound-based Shearwave Propagation in Collagen Fiber Network

High-intensity focused ultrasound (HIFU) has become a tool of choice for non-invasive tissue ablation and other therapeutic applications. HIFU spatially targets a tissue precisely by focusing acoustic waves using an ultrasound transducer. Extracellular matrix’s (ECM) architecture, primarily collagen structure and orientation, affects tissue stiffness, which may have an impact on HIFU treatment response. This study aims to investigate the characteristics of ultrasound-induced shear waves on the transmitting frequency of HIFU and the structural architecture of the collagen network. We have numerically simulated a two-dimensional computational model of a collagen fiber network, where the fibers are arranged randomly or in aligned configurations, to assess their biomechanical response against the transducer’s operating frequencies. From the simulation, we observed a direct correlation between the shearwave speed and the crosslink density. Furthermore, we noticed that the shearwave propagation is influenced by the fiber orientation within the network. This study is a step toward analyzing the spatiotemporal effect of shearwave propagation in collagen tissues to ultrasound perturbation for subsequent imaging and therapy.