MR/CT Multimodal Registration of Short-Axis Slices in CT Volumes

This paper deals with the registration of magnetic resonance (MR) and computerized tomography (CT) cardiac images. We use a multimodal iconic algorithm based on the maximisation of the mutual information of the joint histogram of two images. We apply it to the registration of MR and CT cardiac images. The purpose is to determine in a (3D+t) CT data volume, short-axis slices that correspond to the (2D+t) short-axis MR slices, acquired on the same patient. The couples of images should be similar according to their spatial position, orientation and cardiac cycle phase. We used the Powell´s direction set optimization method for the maximisation of the mutual information, which gives good results with an appropriate initialization.