Low dose reconstruction algorithm for differential phase contrast imaging

Article type: Research Article

Authors: Wang, Zhentian^{; ;} | Huang, Zhifeng^; | Zhang, Li^; | Chen, Zhiqiang^; | Kang, Kejun^; | Yin, Hongxia | Wang, Zhenchang | Marco, Stampanoni^;

Affiliations: Department of Engineering Physics, Tsinghua University, Beijing, China | Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education, Beijing, China | Swiss Light Source, Paul Scherrer Institut, Villigen PSI, Switzerland | Medical Imaging Center, Beijing TongRen Hospital, Capital Medical University, Beijing, China | Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland

Note: [] Corresponding author. Tel.: +41 076 768 1340; E-mail: wang.zhentian@gmail.com

Abstract: Differential phase contrast imaging computed tomography (DPCI-CT) is a novel x-ray inspection method to reconstruct the distribution of refraction index rather than the attenuation coefficient in weakly absorbing samples. In this paper, we propose an iterative reconstruction algorithm for DPCI-CT which benefits from the new compressed sensing theory. We first realize a differential algebraic reconstruction technique (DART) by discretizing the projection process of the differential phase contrast imaging into a linear partial derivative matrix. In this way the compressed sensing reconstruction problem of DPCI reconstruction can be transformed to a resolved problem in the transmission imaging CT. Our algorithm has the potential to reconstruct the refraction index distribution of the sample from highly undersampled projection data. Thus it can significantly reduce the dose and inspection time. The proposed algorithm has been validated by numerical simulations and actual experiments.

Keywords: X-ray, phase contrast imaging, compressed sensing and computed tomography

DOI: 10.3233/XST-2011-0303

Journal: Journal of X-Ray Science and Technology, vol. 19, no. 3, pp. 403-415, 2011