An a priori information based algorithm for artifact preventive reconstruction in few-view computed tomography

The paper considers a new iterative algorithm for tomographic image reconstruction when a very limited number of projections are registered. The algorithm uses a priori information on the discrete values of the object function to be reconstructed and is based on the known multiplicative algebraic reconstruction technique (MART). The new algorithm we called MART-AP organizes a cycle of “external” iterations where the image is corrected at each iteration, using the MART and an image mask synthesized with the help of a priori information. It has been shown in numerical experiment that the algorithm proposed helps completely remove streaklike artifacts usually present on the tomograms which were reconstructed in conditions of strongly incomplete data.