关键词: 自适应自由变形法, 多模图像配准, 层次B样条, 梯度下降, 并行计算, 水平集方法

Abstract: In order to realize the automatic registration of thorax multimodal medical images，a rapid image registration method based on hierarchical adaptive free-form deformation is proposed.Firstly，the edge of thorax is extracted by C-V level sets algorithm，and feature points are matched automatically which is based on parallel computing method.Then，the global coarse registration of thorax multimodal medical images is modeled by principal axes algorithm.Finally，the local fine registration of thorax multimodal medical images is realized by a Free-Form Deformation（FFD） based on hierarchical B-splines.Moreover，the FFD parameters are generated rapidly by gradient descent and maximization of mutual information.Experiments demonstrate the good performance of the proposed method.

Key words: adaptive free-form deformation, multimodal image registration, hierarchical B-spline, gradient descent, parallel computing, level sets method