Nonlinear elasticity imaging with dual frequency ultrasound

Elasticity imaging has shown to enhance diagnostic capabilities of disease as tissue elasticity is often associated with pathological condition. Methods such as Acoustic Radiation Force Impulse imaging and Supersonic Shear Wave imaging have shown good results at shallow depths. Second-order ultrasound field (SURF) imaging is a dual band imaging technique that utilizes a low frequency (LF) pulse to manipulate the nonlinear elasticity of the medium observed by a co-propagating high frequency pulse (HF). The manipulation of the material parameters causes the HF to experience a change in propagation velocity which depends on the manipulation pressure and nonlinear elasticity of the medium. The change in propagation velocity causes an accumulative delay or advancement compared to a single HF pulse, called the nonlinear propagation delay (NPD). By transmitting multiple pulse complexes with different LF polarities the technique has proven capabilities for suppression of multiple scattering noise. By observing lo...