Metal Artifact Reduction and Image Processing of Cone-Beam Computed Tomography Data for Mobile C-Arm CT Devices
A new method to reduce artifacts (MAR), produced by high-density objects, especially metal implants (MI), in
X-ray CBCT is presented.
MIs located in the field of view (FOV) result in artifacts influencing clinical diagnostics
and treatments. The novel method reduces metal artifacts by virtually replacing MIs by tissue objects of the
same shape. This corrected data can be reconstructed with significantly reduced artifacts. After reconstruction,
the segmented 3D MIs were re-inserted into the corrected 3D volume. The method was developed for
mobile C-arm CBCTs, where misalignments between original 2D data and forward projections must be adjusted
before correction. While doing research on MAR it became obvious that large MIs were hard to segment. Since a good segmentation is a very important prerequisite for an efficient MAR, therefore it was necessary to develop a new segmentation technique by combining two thresholding processes with a reconstruction. These techniques are applied to clinical data and the results are presented.