Recovery guarantees for compressed sensing photoacoustic tomography
Alessandro Felisi
TL;DR
This work addresses stable recovery in photoacoustic tomography (PAT) when data are available only on a partial boundary. By imposing a wavelet-sparse prior on the initial pressure $u_0$ and leveraging a general compressed sensing-inverse problems framework, it proves Lipschitz-stable recovery from $m$ random local-average measurements on small detectors, provided $m$ scales as $m\gtrsim j_0 s$ up to log factors and the detectors satisfy a diameter bound $\mathrm{diam}_{\mathbb{R}^3}(E_i)\le\mu 2^{-j_0}$ with truncation error controlled. The reconstruction is obtained by solving an $\ell^1$-minimization over a truncated wavelet subspace $\mathcal{M}_{\le j_0}$, and the result accommodates noise of level $\beta$ and a sparsity defect. The analysis combines forward-map stability (via a quasi-diagonalization bound), a balancing property, and coherence bounds of tensorized wavelets, together with a trace identity on spheres and Huygens’ principle; it further extends to general sensing patterns. Practically, the findings provide the first rigorous theoretical guarantees for PSAT-like recovery in PAT under partial data and randomized detectors, enabling efficient and provable reconstruction from compressed boundary measurements.
Abstract
Photoacoustic tomography is an emerging medical imaging technology whose primary aim is to map the high-contrast optical properties of biological tissues by leveraging high-resolution ultrasound measurements. Mathematically, this can be framed as an inverse source problem for the wave equation over a specific domain. In this work, for the first time, it is shown how, by assuming signal sparsity, it is possible to establish rigorous stable recovery guarantees when the data collection is given by spatial averages restricted to a limited portion of the boundary. Our framework encompasses many approaches that have been considered in the literature. The result is a consequence of a general framework for subsampled inverse problems developed in previous works and refined stability estimates for an inverse problem for the wave equation with surface measurements.
