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arXiv · 1511.03384

An algorithm for constrained one-step inversion of spectral CT data

Rina Foygel Barber·Emil Y. Sidky·Taly Gilat Schmidt·Xiaochuan Pan
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Abstract

We develop a primal-dual algorithm that allows for one-step inversion of spectral CT transmission photon counts data to a basis map decomposition. The algorithm allows for image constraints to be enforced on the basis maps during the inversion. The derivation of the algorithm makes use of a local upper bounding quadratic approximation to generate descent steps for non-convex spectral CT data discrepancy terms, combined with a new convex-concave optimization algorithm. Convergence of the algorithm is demonstrated on simulated spectral CT data. Simulations with noise and anthropomorphic phantoms show examples of how to employ the constrained one-step algorithm for spectral CT data.

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Rina Foygel Barber, Emil Y. Sidky, Taly Gilat Schmidt, Xiaochuan Pan. 2015-11-11. An algorithm for constrained one-step inversion of spectral CT data. https://doi.org/10.1088/0031-9155%2F61%2F10%2F3784

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