Abstract.

The presence of high absorbing inclusions, e.g. metals, causes appearance of artifacts on CT reconstructed images. This paper treats ways of suppressing such artifacts. A constrained optimization problem is stated within the formulated artifact model. The problem is solved on input images of size 64x64 pixels, using the quadratic additive penalties and using the logarithmic barrier functions. The reconstructions are performed using modelled data, imitating inclusion of metals into tooth tissue. A comparison between FBP, Soft inequalities and barrier function methods is present. Results show that although methods fail to fully remove the artifacts, they succeed in providing some useful features to reconstructed images.

Keywords:

computed tomography, algebraic method, barrier function method, high-absorbing inclusions, metal artifacts.

PP. 117-123.

DOI: 10.14357/20790279180513

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