Towards Understanding Preservation of Periodic Object Motion in Computed Tomography

In this paper, we study periodic object motion in computed tomography. Specifically, we investigate the phenomenon that motion may–in a sense–be preserved even in a standard analytical reconstruction that assumes a static object. In fact, these preserved motion patterns reappear in a forward-projection of the allegedly static reconstruction. In numerical simulations abstracting the cardiac anatomy, we show that not only the type of motion, but also the sharpness of the boundary of the moving object affects how much of the motion is preserved.