Fully Stochastic Reconstruction Methods in Coupled Physics Imaging

Abstract

Coupled physics imaging methods combine image contrast from one physical process with observations using a secondary process; several modalities in acousto-optical imaging follow this concept wherein optical contrast is observed with acoustic measurements. For the inverse problem both an optical and acoustic model need to be inverted. Classical methods that involve a non-linear optimisation approach can be combined with advances in stochastic subsamplings strategies that are in part inspired by machine learning applications. In such approaches the forward problem is considered deterministic and the stochasticity involves splitting of an objective function into sub functions that approach the fully sampled problem in an expectation sense.

In this work, the speaker and his collaborators consider where the forward problem is also solved stochastically, by a Monte Carlo simulation of photon propagation. By adjusting the batch size in the forward and inverse problems together, they can achieve better performance than if subsampling is performed separately.

This is a joint work with S. POWELL, C. MACDONALD, N. HÄNNINEN, A. PULKKINEN, T. TARVAINEN.

About the Speaker

Prof. Simon ARRIDGE completed his BA in Physics at the University of Cambridge in 1981 and his PhD in Medical Physics at the University College London (UCL) in 1992. He subsequently joined the Department of Computer Science at UCL as a Lecturer and has been a Professor of Image Processing since 2001. He has also been a Visiting Professor in the Department of Mathematics of UCL since 2011.

Prof. Arridge is widely known as one of the originators of the field of diffuse optical tomography (DOT). A special focus of his research in the last decade has been imaging from coupled physics and in particular photoacoustic tomography (PAT). He has been a member of the editorial board of the Institute of Physics journal, Inverse Problems since 2000, and was the Editor-In-Chief in 2015-2019.

Prof. Arridge was elected a Fellow of the Institute of Physics in 2005. He is also a member of the Foreign Advisory Board of the Finnish Inverse Problems Society.

For Attendees' Attention

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About the Program

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