Patent ID: 10327739

Abstract:
Ultrasound radiation using a single tone burst pulse is applied to a selected location in a tissue region. The induced shear wave is detected in the region and its spectral distribution is calculated and analyzed. This detection may be repeated with other excitation pulses having different widths or different shapes at the same location. The spectral analysis of the detected shear wave is performed according to a nonlinear shear model for solving nonlinearity and viscoelasticity of the tissue at a single location. The detection location can be at one point at a time for imaging two-dimensional or three-dimensional tissue nonlinearities and shear wave properties including nonlinear magnitude variations, nonlinear phase variations, nonlinear coefficients, and viscoelasticity. The induced shear wave are detected at multiple locations along the shear propagation directions for calculating different shear group velocities and different shear phase velocities using different excitation pulses, and calculating nonlinearity and viscoelasticity.