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arXiv · 2604.27428

Wave-Equation Migration Velocity Analysis for Multistatic Synthetic Aperture Ultrasound

Rehman Ali·Trevor M. Mitcham·Marvin M. Doyley·Nebojsa Duric·Jeremy J. Dahl
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Abstract

Sound speed heterogeneities can create aberrations in B-mode ultrasound images by inducing tissue-dependent delays and diffractive effects that conventional beamforming does not incorporate. By using the Fourier split-step method to simulate pressure fields in heterogenous sound speed media, reverse-time migration (RTM) can reconstruct the B-mode image by cross-correlating transmitted and received pressure fields. As a result, RTM is differentiable with respect to sound speed. This enables the reconstruction of the sound speed profile that minimizes the aberration in the B-mode image. In seismic imaging, this form of diffraction tomography, known as wave-equation migration velocity analysis, can roughly be understood as a type of full-waveform inversion (FWI) that acts in the image domain rather than errors in the received channel data. This is the first work applying WEMVA to medical pulse-echo ultrasound imaging. Phantom experiments show dramatic improvements in image quality with measured improvements in point target resolution from 1.22$\pm$1.01 to 0.32$\pm$0.07 mm and lesion contrast from 3.05 to 4.39 dB.

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Rehman Ali, Trevor M. Mitcham, Marvin M. Doyley, Nebojsa Duric, Jeremy J. Dahl. 2026-04-30. Wave-Equation Migration Velocity Analysis for Multistatic Synthetic Aperture Ultrasound. https://arxiv.org/abs/2604.27428

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