Ultrasonic wavefront propagation in an inhomogeneous medium, the female breast

Ultrasound measurements at 3 and 4 MHz of a large population of wavefronts transmitted through female breasts show that the wavefront amplitude distribution is Rayleigh. This finding implies that strong scattering and/or refraction are the dominant causes of distortion. The wavefront received from an inhomogeneous medium is the superposition of an incident wave plus a scattered wave. If the scattered field is weak, the received field is dominated by the incident field and the wavefront amplitude distribution is Rician. If the scattered field is strong, the received field is primarily the scattered field and the wavefront amplitude distribution is Rayleigh. If, in addition to scattering, refraction between bodies of different refractive indexes occurs, the total net effect on the wavefront is the same as for strong scattering. This is what the authors have observed in the highly refractive female breast