A model for the propagation and scattering of ultrasound in tissue.

Electronics Institute, Technical University of Denmark, Lyngby.
The Journal of the Acoustical Society of America (Impact Factor: 1.65). 02/1991; 89(1):182-90.
Source: PubMed

ABSTRACT An inhomogeneous wave equation is derived describing propagation and scattering of ultrasound in an inhomogeneous medium. The scattering term is a function of density and propagation velocity perturbations. The integral solution to the wave equation is combined with a general description of the field from typical transducers used in clinical ultrasound to yield a model for the received pulse-echo pressure field. Analytic expressions are found in the literature for a number of transducers, and any transducer excitation can be incorporated into the model. An example is given for a concave, nonapodized transducer in which the predicted pressure field is compared to a measured field.

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