基于多分辨率的多模态医学图像配准

Multimodality images registration based on multi-resolution

提出了一种多分辨率多模态医学图像配准方法来提高图像的配准速度与精度。利用小波函数对图像进行多层分解,采用改进的Powell优化算法寻找待配准图像间的最大互信(MMI)。配准首先从图像金字塔中分辨率最低的0层图像开始,将0层图像配准获得的变形参数作为1层图像配准的起始参数,重复该过程直到完成最高精度层的图像配准。CT/MRI和CT/PET图像配准结果证明基于小波分解的多分辨率配准方法具有避免优化算子陷入局部极值、算子收敛速度快和配准精度高等优点。

A multi-resolution multi-mode medical image registration method is proposed to improve the speed and accuracy of registration. The images were decomposed by wavelet function, and expanded Powell optimization algorithm was used to find the maximal mutual information （MMI） between images. The registration starts from the lowest-resolution image level 0 of the image pyramid, the deformation parameters of image level 0 registration are available as the initial parameters of image level 1, repeating the process until the completion of the highest-resolution image registration. The image registration results of CT/MRI and CT/PET show that wavelet-based multi-mode registration method has advantages such as avoiding local maxima, fast convergence and high accuracy.