Optimization of Effective Parameters on Acoustic Radiation Force Shear Waves Interference Patterns Elastography by using a Finite Element Model

Variation in mechanical properties of soft tissues may be a sign of disease. ‎Since, some disease like fibrosis or cancer change the stiffness of related tissue, ‎we can assess the disease of soft tissue with its elasticity. The elastic stiffness ‎properties of soft tissues can be estimated by the use of locally induced ‎displacements and shear waves.‎We have made a two-dimensional plane finite element model as soft tissue. The soft tissue has been exposed by two amplitudes modulated high intensity ‎focused ultrasound transducer (AMHIFU) and hence shear wave interference patterns which can be captured by lower frame rate imaging are generated. The acoustic radiation force created by a self-focusing ultrasound transducer has been determined from an ultrasound pressure field simulation. A Gaussian function was fitted to the resulting acoustic radiation force (ARF) field and implemented in the form of a body force in the finite element model. The effect of different excitation parameters for elasticity estimation is investigated. The results show that choosing an appropriate excitation characteristic leads to better clinical usage.shear waves interference patterns elastography which doesn’t need high frame rate imaging with optimized parameters can be used as a non-invasive method for measuring the elastic stiffness of soft tissues.