Abstract: BACKGROUND: 4D cardiac computed tomography aims at reconstructing
the beating heart from a series of 2D projections and the simultaneously
acquired electrocardiogram. Each cardiac phase is reconstructed by exploiting
the subset of projections acquired during this particular cardiac phase only.
In these conditions, the Feldkamp, Davis and Kress method (FDK) generates large
streak artifacts in the reconstructed volumes, hampering the medical
interpretation. These artifacts can be substantially reduced by deconvolution
methods. OBJECTIVE: The aim of this paper is to compare two 4D
cardiac CT reconstruction methods based on deconvolution, and to evaluate their
practical benefits on two applications: cardiac micro CT and human cardiac
C-arm CT. METHODS: The first evaluated method builds upon inverse
filtering. It has been proposed recently and demonstrated on 4D cardiac micro
CT. The second one is an iterative deconvolution method, and turns out
equivalent to an ECG-gated Iterative Filtered Back Projection (ECG-gated
IFBP). RESULTS: Results are presented on simulated data in 2D
parallel beam, 2D fan beam and 3D cone beam geometries. CONCLUSIONS: Both methods are efficient on the cardiac micro CT simulations, but
insufficient to handle 4D human cardiac C-Arm CT simulations. Overall,
ECG-gated IFPB largely outperforms the inverse filtering method.
