Metal Artifact Reduction in Computed Tomography Using Nonequispaced Fourier Transform

Metal objects in the field of view of a computed tomography (CT) scanner cause several artifacts inside the reconstructed image. By reducing the influence of these metallic objects the image quality can be enhanced. We propose a metal artifact reduction (MAR) method based on interpolation using Nonequispaced Fast Fourier Transforms (NFFT). By damping the transformation additional a priori knowledge may be included during the interpolation step. The results are reconstructed with a weighted maximum likelihood expectation maximization algorithm (lambda-MLEM) and finally compared to two common one dimensional polynomial interpolation methods.