Plane-Wave Acoustoelectric Tomography for Sparse-Angle Current Source Imaging

Abstract

Conventional acoustoelectric imaging (AEI) is limited by the tradeoff between field of view (FOV), scan efficiency, and reconstruction quality. This article presents a plane-wave acoustoelectric tomography (PW-AET) framework for sparse-angle acoustoelectric (AE) source imaging in a saline phantom. The plane-wave (PW) acquisition model is formulated and related to the Radon transform, providing the basis for tomographic reconstruction from multiangle AE measurements. To improve reconstruction quality under limited-angle sampling, linear back-projection (LBP) and the simultaneous algebraic reconstruction technique (SART) are used to generate physics-based initial estimates, with a simulation-trained U-Net then applied as a proof-of-concept image-domain postprocessing module for sparse-angle artifact suppression. Broadband chirp excitation is further incorporated to improve demodulation robustness relative to short-pulse operation. Controlled phantom experiments demonstrate millimeter-scale source reconstruction, including dipole-pair discrimination and recovery of heterogeneous sources with distinct size scales. In dual-frequency source-emulation experiments, the framework further demonstrated frequency-specific temporal tracking, spectral discrimination, and fused spatial localization for two electrically injected sources at 7 and 13 Hz. Relative to the reference focused ultrasound (FUS) scanning configuration used in this study, PW-AET provides broader instantaneous field coverage and improved task-specific source separability under the tested conditions. These results support PW-AET as a promising measurement framework for sparse-angle AE source imaging under controlled phantom conditions and provide a basis for further development toward wider field and faster AE source-imaging systems.