title: Nonlinear image registration with bidirectional metric and reciprocal regularization.
abstract: Nonlinear registration is an important technique to align two different images and widely applied in medical image analysis. In this paper, we develop a novel nonlinear registration framework based on the diffeomorphic demons, where a reciprocal regularizer is introduced to assume that the deformation between two images is an exact diffeomorphism. In detail, first, we adopt a bidirectional metric to improve the symmetry of the energy functional, whose variables are two reciprocal deformations. Secondly, we slack these two deformations into two independent variables and introduce a reciprocal regularizer to assure the deformations being the exact diffeomorphism. Then, we utilize an alternating iterative strategy to decouple the model into two minimizing subproblems, where a new closed form for the approximate velocity of deformation is calculated. Finally, we compare our proposed algorithm on two data sets of real brain MR images with two relative and conventional methods. The results validate that our proposed method improves accuracy and robustness of registration, as well as the gained bidirectional deformations are actually reciprocal.
authors.affiliation: Department of Mathematics, Shanghai University, Shanghai 200444, China.
authors.forename: Shihui
authors.initials: S
authors.lastname: Ying
authors.affiliation: Department of Mathematics, Shanghai University, Shanghai 200444, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.affiliation: Med-X Research Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Xiao
authors.affiliation: Department of Mathematics, Shanghai University, Shanghai 200444, China.
authors.forename: Yaxin
authors.initials: Y
authors.lastname: Peng
authors.affiliation: Institute of Artificial Intelligence and Robotics, Xi'an Jiaotong University, Xi'an 710049, China.
authors.forename: Shaoyi
authors.initials: S
authors.lastname: Du
authors.affiliation: The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China.
authors.forename: Meifeng
authors.initials: M
authors.lastname: Xu
mesh_terms: D000465:Algorithms; D001921:Brain / Q000000981:diagnostic imaging*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D017711:Nonlinear Dynamics