Three-dimensional shear wave imaging based on full-field optical-sectioned laser speckle contrast imaging

Shear wave imaging with optical detection system has the potential to achieve high sensitivity and resolution. In our previous report, laser speckle contrast imaging (LSCI) has been implemented to demonstrate non-scanning two-dimensional shear wave imaging, where the shear wave speed estimation errors of less than 4% were achieved on homogeneous phantoms. In this report, the system was further developed to include one-dimensional mechanical scanning and optical sectioning. With this, a feasibility study in three-dimensional shear wave imaging is presented. The lateral (X) and depth (Y) shear wave imaging resolutions of the system were evaluated separately on two heterogeneous agar phantoms. The lateral and depth resolutions achieved are 176 μm and 1.5 mm, respectively. The developed system is potentially suitable for three-dimensional shear wave imaging in low-scattering samples, such as three-dimensional cell cultures, with sub-millimeter resolution.