Affiliations: [a] Department of Electrical and Computer Engineering, University of Massachusetts Lowell, Lowell, MA, USA | [b] Biomedical Imaging Center, Center for Biotechnology and Interdisciplinary Studies, Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA | [c] LMAM, School of Mathematical Sciences, Peking University, Beijing, China | [d] CT Systems and Applications Laboratory, GE Global Research Center, Niskayuna, NY, USA
Correspondence:
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Corresponding author: Hengyong Yu, Department of Electrical and Computer Engineering, University of Massachusetts Lowell, Lowell, MA 01854, USA. E-mail:[email protected]
Abstract: It is well known that CT projections are redundant. Over
the past decades, significant efforts have been devoted to characterize the
data redundancy in different aspects. Very recently, Clackdoyle and Desbat
reported a new integral-type data consistency condition (DCC) for truncated
2D parallel-beam projections, which can be applied to a region inside a
field of view (FOV) but outside of the convex hull of the compact support of
an object. Inspired by their work, here we derive a more general condition
for 2D fan-beam geometry with a general scanning trajectory. This extended
DCC is verified with simulated projections of the Shepp-Logan phantom and a
clinically collected sinogram. Then, we demonstrate an application of the
proposed DCC.
Keywords: Data consistency condition, fan-beam geometry, truncated projections, general scanning trajectory, interior problem, motion artifact reduction
