Comparison of five one-step reconstruction algorithms for spectral CT.

Comparison of five one-step reconstruction algorithms for spectral CT.
Phys Med Biol. 2018 Nov 22;63(23):235001
Authors: Mory C, Sixou B, Si-Mohamed S, Boussel L, Rit S
Abstract
Over the last decade, dual-energy CT scanners have gone from prototypes to clinically available machines, and spectral photon counting CT scanners are following. They require a specific reconstruction process, consisting of two steps: material decomposition and tomographic reconstruction. Image-based methods perform reconstruction, then decomposition, while projection-based methods perform decomposition first, and then reconstruction. As an alternative, 'one-step inversion' methods have been proposed, which perform decomposition and reconstruction simultaneously. Unfortunately, one-step methods are typically slower than their two-step counterparts, and in most CT applications, reconstruction time is critical. This paper therefore proposes to compare the convergence speeds of five one-step algorithms. We adapted all these algorithms to solve the same problem: spectral photon-counting CT reconstruction from five energy bins, using a three materials decomposition basis and spatial regularization. The paper compares a Bayesian method which uses non-linear conjugate gradient for minimization (Cai et al 2013 Med. Phys. 40 111916-31), three methods based on quadratic surrogates (Long and Fessler 2014 IEEE Trans. Med. Imaging 33 1614-26, Weidinger et al 2016 Int. J. ...

Source: Physics in Medicine and Biology - November 22, 2018 Category: Physics Authors: Mory C, Sixou B, Si-Mohamed S, Boussel L, Rit S Tags: Phys Med Biol Source Type: research