Time-domain reconstruction for thermoacoustic tomography in a spherical geometry

TLDR

The study presents reconstruction-based microwave‑induced thermoacoustic tomography in a spherical configuration. Thermoacoustic waves generated by microwave pulses in tissue samples are captured by a wide‑band unfocused ultrasonic transducer array on a spherical surface, and the acquired multi‑directional data are used to derive an exact reconstruction solution that is approximated by a modified backprojection algorithm. Experimental results show that the reconstructed images closely match the original samples and achieve a spatial resolution of 0.5 mm.

Abstract

Reconstruction-based microwave-induced thermoacoustic tomography in a spherical configuration is presented. Thermoacoustic waves from biological tissue samples excited by microwave pulses are measured by a wide-band unfocused ultrasonic transducer, which is set on a spherical surface enclosing the sample. Sufficient data are acquired from different directions to reconstruct the microwave absorption distribution. An exact reconstruction solution is derived and approximated to a modified backprojection algorithm. Experiments demonstrate that the reconstructed images agree well with the original samples. The spatial resolution of the system reaches 0.5 mm.