Estimation of attenuation in tissue as a function of depth from RF ultrasound data

Abstract

When an ultrasound beam from a transducer reaches tissue, the signal will be attenuated. This attenuation is partly caused by absorption, and partly by scattering. For most soft tissues absorption accounts for most of the attenuation.

Research has shown that different types of tissues will display different attenuation characteristics. For instance, cirrhotic liver tissue will absorb more of the ultrasonic signal than healthy tissue. Accurate non-intrusive measurement of attenuation could thus be an important diagnostic aid.

In this thesis we will review various methods for estimating this attenuation, and compare their efficiency under various conditions. To facilitate this comparison we will be using the ultrasound simulation program Field II.