Mechanical Finite Element Analysis of ARFI Imaging

Focused, impulsive acoustic radiation force excitations create complicated dynamic displacement fields in elastic materials. Finite Element Methods (FEM) have been used to study these dynamic displacement fields to determine how material properties and structural information about soft tissue can be distilled from these data sets. Multiple areas of ARFI imaging have been studied with these models, including:

  • Model validation using gelatin-based, tissue-mimicking phantoms,
  • The influence that spherical inclusions (lesions) with varying strucutual and material porperties have on the displacement field dynamics generated by impulsive acoustic radiation force excitations,
  • The impact of ultrasonically tracking these dynamic displacement fields, including the effects of scatterer shearing leading to displacement underestimation.

Finite element analysis has also been used to study the use of tracking the speed of shear waves generated by the impulsive acoustic radiation force excitations to reconstruct the shear modulus of soft tissue. More details about this work can be found under the Liver Fibrosis Quanitification research link.