Multimodal intra- and inter-subject nonrigid registration of small animal images.
This dissertation presents several innovations in the area of small animal image registration. We start with the problem of reconstructing 3D histological volumes. A new method is proposed to normalize intensity across slices. We then propose a solution that enhances the reconstructed histological volumes. Our results have shown that with as few as four histological volumes we can produce one virtual volume that is substantially better than any of the volumes used to create it. But, brain studies are only a small part of the studies being conducted with small animals. Registering the whole body volumes brings a new set of challenges. Hence, a fully automatic registration algorithm for whole body CT images is proposed in this dissertation. Qualitative and quantitative validation results show the algorithm can successfully register images even when these images are substantially different in shape and size. Furthermore, one constrained intensity based nonrigid registration algorithm is presented to permit the deformation of soft tissues while limiting the deformation of bony structures.