Keywords:
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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