1. A computer-based visualization system for visualizing anatomical structure and a graft implant which is to be deployed adjacent the anatomical structure, comprising: a 3-D computer model of the anatomical structure which is to be visualized, said 3-D computer model comprising at least one first software object, wherein said at least one first software object corresponds to the anatomical structure which is to be visualized; a database of second software objects, wherein at least one of said second software objects corresponds to a graft implant which is to be deployed adjacent the anatomical structure; selection apparatus for permitting a user to select said at least one of said second software objects; registration apparatus for positioning said selected at least one of said second software objects into said 3-D computer model so as to create an augmented 3-D computer model, with said selected at least one of said second software objects being positioned in said augmented 3-D computer model in proper registration with said at least one first software object contained in said augmented 3-D model; and processing apparatus for generating an image of said augmented 3-D computer model so as to simultaneously provide a view of said at least one first software object and said selected at least one second software object.