Modified Parker weights for super short scan cone beam CT

Dirk Schäfer, Peter van de Haar, Michael Grass


Published in: Fully3D 2017 Proceedings


Circular cone beam CT (CBCT) acquisitions with less than 180° plus fan angle are desired for practical reasons in the interventional setup. Strong shading artefacts are present with standard FDK reconstruction even for voxels with 180° coverage. The use of modified Parker weights has been proposed to correctly handle redundant data and correct for shading in the limited angle areas. However, this results in discontinuous weighting functions leading to streak artefacts in the FDK reconstruction. We propose to combine the modified Parker weights with a filtered back-projection (FBP) algorithm capable of handling redundancy weights after filtering. Improved image quality is shown for this approach in terms of visual appearance and quantitative measures.
Dirk Schäfer
Philips Research Hamburg
Peter van de Haar
Philips Healthcare
Michael Grass
Philips Research Hamburg
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