Two-step Non-linear Medical Image Registration Based on Image Intensity

摘要

A two-step non-linear medical image registration approach is proposed, based on the image intensity. In the first step, the global affine medical image registration is used to establish one-to-one mapping between the two images to be registered. After this first step, the images are registered up to small local elastic deformation. Then the mapped images are used as inputs in the second step, during which, the study image is modeled as elastic sheet by being divided into several sub-images. Moving the individual sub-image in the reference image, the local displacement vectors are found and the global elastic transformation is achieved by assimilating all of the local transformation into a continuous transformation. This algorithm has been tested by both simulated and clinical tomographic images.