Vibro-elastography: Absolute elasticity from motorized 3D ultrasound measurements of harmonic motion vectors

Absolute elasticity images can be generated from harmonic motion vector measurements over a volume, usually with MRI, called MR elastography (MRE). This work aims to apply the same method using motorized 3D ultrasound. Previous work has demonstrated measurement of motion vectors over ultrasound volumes, however measuring dynamic motion on the order of hundreds of cycles per second remains a challenge. A solution is proposed based on synchronizing the ultrasound acquisition with the mechanical exciter producing the waves. Measured motion is smoothed using a constraint on the divergence. An elasticity reconstruction algorithm used in MRE is applied to ultrasound data captured on a tissue mimicking phantom. The reconstructed values are within 20% and 8% of previous MRE measurements of hard and soft regions, respectively.