The research objective of this award is to examine the cause-effect relationship between changes in trabecular bone microarchitecture and measured poroelastic ultrasound wave properties. The energy of an ultrasound wave propagating through a fluid-saturated porous medium such as trabecular bone creates two distinct poroelastic waves which travel with velocities and attenuations that depend on the properties of solid and fluid constituents of bone. Studies conducted under this award will use analytical, numerical and experimental approaches to determine the effect of changes in pore microarchitecture, material properties and wave frequency on the velocity and attenuation of these two waves. The proposed parametric study will investigate wave propagation properties in both experimental and finite-difference time-domain numerical simulations in 3D printed porous medium models. An anisotropic poroelastic theoretical approach will be used to distinguish the contribution of solid and fluid constituents on measured ultrasound wave signals in both 3D printed models and human trabecular bones. The long-term objective of this research is to change the technology used for the assessment of osteoporosis from the current standard of ionizing and expensive DEXA devices to lower cost, non-ionizing ultrasound systems that access microarchitecture as well as material properties.
If successful, this architectural-based approach will reveal the main microarchitectural determinants of ultrasound wave propagation in porous media, and will improve the non-invasive characterization of changes in trabecular bone during bone loss and osteoporosis. The educational component of this award focuses on developing a multidisciplinary program on bone biomechanics and biomedical imaging for undergraduate students from underrepresented groups at the City College of New York, increasing the number of course modules with numerical modeling, research design and imaging hands-on laboratory experience. The program will provide closely mentored research opportunities for undergraduate students to attract them to follow graduate studies in STEM.
