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arXiv · 1608.05238

Quantitative photoacoustic tomography using forward and adjoint Monte Carlo models of radiance

Roman Hochuli·Samuel Powell·Simon Arridge·Ben Cox
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Abstract

Forward and adjoint Monte Carlo (MC) models of radiance are proposed for use in model-based quantitative photoacoustic tomography. A 2D radiance MC model using a harmonic angular basis is introduced and validated against analytic solutions for the radiance in heterogeneous media. A gradient-based optimisation scheme is then used to recover 2D absorption and scattering coefficients distributions from simulated photoacoustic measurements. It is shown that the functional gradients, which are a challenge to compute efficiently using MC models, can be calculated directly from the coefficients of the harmonic angular basis used in the forward and adjoint models. This work establishes a framework for transport-based quantitative photoacoustic tomography that can fully exploit emerging highly parallel computing architectures.

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Roman Hochuli, Samuel Powell, Simon Arridge, Ben Cox. 2016-08-18. Quantitative photoacoustic tomography using forward and adjoint Monte Carlo models of radiance. https://doi.org/10.1117/1.jbo.21.12.126004

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