Image Reconstruction by ordered subsets expectation maximization method

Abstract

This paper describes the property of ordered subsets expectation maximization (OS-EM) method. This method divides projections into some subsets and acceralates the convergence of the reconstruction. In this paper, the OS-EM method was analized in terms of three parameters: (1) the number of projections which composes a subset, (2) the projection data which composes a subset, and (3) the subset access order among subsets.