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arXiv · 1308.1421

Photoacoustic Tomography in a Rectangular Reflecting Cavity

L. Kunyansky·B. Holman·B. T. Cox
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Abstract

Almost all known image reconstruction algorithms for photoacoustic and thermoacoustic tomography assume that the acoustic waves leave the region of interest after a finite time. This assumption is reasonable if the reflections from the detectors and surrounding surfaces can be neglected or filtered out (for example, by time-gating). However, when the object is surrounded by acoustically hard detector arrays, and/or by additional acoustic mirrors, the acoustic waves will undergo multiple reflections. (In the absence of absorption they would bounce around in such a reverberant cavity forever). This disallows the use of the existing free-space reconstruction techniques. This paper proposes a fast iterative reconstruction algorithm for measurements made at the walls of a rectangular reverberant cavity. We prove the convergence of the iterations under a certain sufficient condition, and demonstrate the effectiveness and efficiency of the algorithm in numerical simulations.

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L. Kunyansky, B. Holman, B. T. Cox. 2013-08-06. Photoacoustic Tomography in a Rectangular Reflecting Cavity. https://doi.org/10.1088/0266-5611%2F29%2F12%2F125010

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