Incorporating Rigid Structures in Non-rigid Registration Using Triangular B-Splines

For non-rigid registration, the objects in medical images are usually treated as a single deformable body with homogeneous stiffness distribution. However, this assumption is invalid for certain parts of the human body, where bony structures move rigidly, while the others may deform. In this paper, we introduce a novel registration technique that models local rigidity of pre-identified rigid structures as well as global non-rigidity in the transformation field using triangular B-splines. In contrast to the conventional registration method based on tensor-product B-splines, our approach recovers local rigid transformation with fewer degrees of freedom (DOFs), and accurately simulates sharp features (C0 continuity) along the interface between deformable regions and rigid structures, because of the unique advantages offered by triangular B-splines, such as flexible triangular domain, local control and space-varying smoothness modeling. The accurate matching of the source image with the...

• Type: Conference
• Year: 2005
• Where: VLSM
• Authors: Kexiang Wang, Ying He 0001, Hong Qin
• Keywords: Computer Vision, Deformable Regions, Rigid Structures, Triangular B-splines, VLSM 2005