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A New Sound Speed Reconstruction Algorithm for Breast Tissue in Ultrasound Computed Tomography

Ultrasound computed tomography (UCT) has the potential to be a new breast cancer imaging technique with high screening sensitivity, real-time scanning, patient safety, and low cost-effectiveness. Popular UCT imaging methods include ray tracing method (RTM), projection-based algorithms (PBA) and full waveform inversion (FWI). Both RTM and PBA do not consider the scattering of the acoustic waves, and obtain reconstructed images with very poor resolution. FWI based on the wave equation allows to obtain a very high image spatial resolution. However, the algorithm requires a large amount of calculation. Source encoding technology can greatly reduce the computational requirements of waveform inversion, but, at the same time, it will generate crosstalk noise. In this paper, a method of full waveform inversion with source encoding based on total variation (FWIS- TV) is proposed. The main feature of this formulation is that it allows obtaining smoother reconstructed images while being more robust to noise compared to other state-of-the-art methods.