ABSTRACT
For a better interpretation of ultrasound images and an accurate measurement of the structure of a tissue (e.g., size or volume of a tumor), ultrasonic properties of biological tissues such as velocity, absorption, attenuation, and scattering must be known. A variety of methods can be used
in vitro
to measure these properties. Performing these measurements
in vivo
, however, is a totally different matter. A number of methods have been developed for
in vivo
measurements with little success (Greenleaf, 1986; Shung and Thieme, 1993).