“…The approach taken in this paper belongs to the second category and the motion model makes use of diffeomorphic deformations. The latter are provided by the large deformation diffeomorphic metric mapping (LDDMM) framework, which is a well-developed framework for diffeomorphic image registration (see, for instance, [53,25,37,5,30,60,54,55,11,12]). Diffeomorphic deformations based on LDDMM were used in [32] for joint image reconstruction and motion estimation in 4D computed tomography (CT), which is based on the growth model of LDDMM [30].…”