The invention relates to a method and an image processing device (50) for the registration of two images (I1, I2) that may for example be provided by a CT scanner (10) and/or an MRI scanner (20). According to one embodiment of the invention, the images are first globally registered (GR) with a given registration algorithm using a first parameter vector (p). A user may then select a region of interest ROI, and a plurality of local registrations (LR1, . . . LRs, . . . LRn) are calculated for this ROI using the same registration algorithm but different parameter vectors (p, p, . . . p). The results of the local registrations (LR1, . . . LRs, . . . LRn) are displayed and the user can select the best local registration(s). In a final step, the selected local registration(s) (LRs) and the global registration (GR) may be merged. Additionally or alternatively, a parameter vector for a local registration in the ROI may be determined by an automatic analysis of the ROI.