“…If nonlinear transformations such as local dilation, contraction, or shearing can be applied to deform the images, registration can be significantly improved. Considerable research has been directed towards development of nonlinear methods in the last decade (Maintz and Viergever, 1998;Toga, 1999;Thompson and Toga, 2000). High-dimensional morphing methods have been suggested that can morph an entire 3D volume to match the intensity values with a canonical anatomy (Evans et al, 1994;Christensen et al, 1996;Christensen et al, 1997;Joshi et al, 1997;Woods et al, 1998).…”