VISCOELASTIC TISSUE PROPERTY MEASUREMENT USING HIGH FREQUENCY ULTRASOUND

A high frequency ultrasound system for viscoelastic tissue property measurement is being developed. A dual-element transducer was used for localized application of acoustic radiation force (ARP) pulses and monitoring of the induced shift. M-mode RP data was evaluated using a correlation based shift estimation algorithm. These displacements are used as input to an on-line tracking of the shear modulus and shear viscosity using an extended Kalman filter (EKF) which utilizes a second order constitutive model of viscoelastic response with unknown parameters. The algorithm was tested using tissue mimicking phantoms described by Nightingale et al., we also demonstrate the feasibility of evaluating the effect of drug in in-vitro porcine eye.