MAT-MI acoustic source reconstruction using ultrasound B-Scan imaging

We present in this study an ultrasound B-scan based imaging approach for magnetoacoustic tomography with magnetic induction (MAT-MI) to reconstruct electrical conductivity distribution. In MAT-MI acoustic waves are generated in the sample by placing it in a static and a time-varying magnetic field. The acoustic waves from these sources propagate in all directions. In the present approach these acoustic signals are collected with a focused ultrasound transducer which confines the collected signal to that from sources along a line. The focused transducer also gives signal gain in the focus region improving the MAT-MI signal quality. The time-resolved acoustic signals are back projected to form a one-dimensional (1D) image of the source distribution along the line. The complete cross-section of the object is obtained by acquiring 1D images along multiple directions in the cross-sectional plane. A simulation model of the image reconstruction method is developed with ultrasound simulations using the Field II program. The present reconstruction results suggest that acoustic source imaging in MAT-MI can be achieved using the much practical ultrasound B scan imaging technique. The developed method is applied to MAT-MI in experiments. This method should allow combining MAT-MI with clinical ultrasound imaging methods and broadening the potential applicability of the technique.