Imaging from multiply scattered waves

We consider the problem of imaging in a region where ultrasonic waves are multiply scattered. A transducer emits ultrasonic pulses in tissue where they scatter from a heterogeneity (e.g. a tumor) in the region of interest (ROI). The reflected signals are recorded and used to produce an image of tissue. Many of the conventional imaging methods assume the wave has scattered just once (Born-approximation) from the heterogeneity before returning to the sensor to be recorded. In reality, waves can scatter several times before returning to the detector. The purpose of this paper is to show how this restriction (the Born approximation or weak, single-scattering approximation) can be partially removed by incorporating a-priori known environmental scatterers, such as a cavity wall or bones into the background velocity model in the context of acoustic medical imaging. We also show how the partial removal of the Born approximation assumption leads to an enhanced angular resolution of heterogeneities that are present. We will illustrate our method using a locally planar scatterer, which is one of the simplest possible environments for the scatterer.