Acoustic Radiation Force Impulse (ARFI) imaging uses short, high-intensity focused ultrasound pulses to generate a localized mechanical displacement (push) in tissue. The resulting tissue motion is tracked using conventional ultrasound to produce either qualitative stiffness maps (Virtual Touch imaging) or quantitative shear wave velocity measurements (Virtual Touch IQ). ARFI-based techniques are the basis for most commercial shear wave elastography implementations and are used extensively for liver fibrosis assessment and lesion characterization.