Ultrasonic backscattering from human tissue: a realistic model

Abstract

The propagation of ultrasound pulses in inhomogeneous media is described; they are scattered by fluctuations in density and compressibility. Some of the echoes recorded by diagnostic pulse echo equipment may be produced in this way. The precise form of the acoustic field backscattered from tissues is calculated using realistic approximations about the nature of tissue inhomogeneities and the form of the pulses used. Only limited information about tissue structure is contained in these signals, and the restrictions imposed by the use of typical pulses are indicated. The implications of this analysis for methods of tissue characterization and clinical imaging are discussed.