From cells to bones: wave physics for biomaterial imaging - Gabrielle Laloy-Borgna (TU Delft, the Netherlands)

In this presentation, I will first describe my doctoral work which consisted in contributing to the development of dynamic micro-elastography, a microscopy-based approach that extended shear wave imaging down to the cellular scale. In particular, I designed an original technique using oscillating microbubbles as micron-sized, contactless actuators, which enabled contactless shear wave elastography on single cells of only 15 μm in diameter. I further applied optical micro-elastography to multicellular aggregates, introducing magnetic nanoparticles as diffuse field actuators. Finally, I explored guided wave propagation in microscopic (retinal arteries) and macroscopic (carotid artery) blood vessels, where I revealed the existence of a previously overlooked flexural pulse wave. In a second part, I will describe my postdoctoral research, extending these wave-based imaging concepts to the challenging domain of bone ultrasonography. Conventional ultrasound fails to image inside and behind bone due to speed-of-sound heterogeneities of the imaged medium. To overcome this, we use seismology-inspired approaches to estimate bone wave speed anisotropy and then apply ray-tracing beamforming to perform aberration correction and reconstruct anatomical images of the tibia in vivo. In addition, intra-osseous blood flow is detected using Doppler ultrasound.

Contact: Dorian Bouchet