Abstract: A system and method to conduct image segmentation by imaging target morphological shapes evolving from one 2-dimension (2-D) image slice to one or more nearby neighboring 2-D images taken from a 3-dimension (3-D) image. One area defined by a user as a target on an image slice can be found in a corresponding area on a nearby neighboring image slice by using a deformation field generated with deformable image registration procedure between these two image slices. It allows the user to distinguish target and background areas with the same or similar image intensities.