Analyzing the intrinsic relations between the diffusion and fluid deformable registration methods

Physical model based non rigid registration algorithm describes image deformation procedures by mimicking the physical deformation properties of different substances. In this article, the diffusion model based Demons algorithm is interpreted in PDE framework as elastic and fluid model did, and is discussed on the differences and similarities between these methods. Moreover, on the basis of the established unified framework, we analyze why the deformation field is not topology preserved without additional adjustment procedure and the experimental results verify the conclusion.