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arXiv · 2603.21655

Utilising a learned forward operator in the inverse problem of photoacoustic tomography

Karoliina Puronhaara·Teemu Sahlström·Andreas Hauptmann·Tanja Tarvainen
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Abstract

We study the use of a learned forward operator in the inverse problem of photoacoustic tomography. The Fourier neural operator to approximate the photoacoustic wave propagation is used. Further, the inverse problem is solved using a gradient-based approach with automatic differentiation. The methodology is evaluated using numerical simulations, and the results are compared to a conventional approach, where the forward operator is approximated using the pseudospectral $k$-space method. The results show that the learned forward operator can be used to approximate the photoacoustic wave propagation with good accuracy, and that it can be utilised as a computationally efficient forward operator in solving the inverse problem of photoacoustic tomography.

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Karoliina Puronhaara, Teemu Sahlström, Andreas Hauptmann, Tanja Tarvainen. 2026-03-23. Utilising a learned forward operator in the inverse problem of photoacoustic tomography. https://arxiv.org/abs/2603.21655

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