the present invention provides an anatomical visualization system comprising a first database that comprises a plurality of 2 - d slice images generated by scanning a structure . the 2 - d slice images are stored in a first data format . a second database is also provided that comprises a 3 - d computer model of the scanned structure . the 3 - d computer model comprises a first software object that is defined by a 3 - d geometry database . apparatus are provided for inserting a second software object into the 3 - d computer model so as to augment the 3 - d computer model . the second software object is also defined by a 3 - d geometry database , and includes a planar surface . apparatus for determining the specific 2 - d slice image associated with the position of the planar surface of the second software object within the augmented 3 - d computer model are provided in a preferred embodiment of the invention . also provided are apparatus for texture mapping the specific 2 - d slice image onto the planar surface of the second software object . display apparatus are provided for displaying an image of the augmented 3 - d computer model so as to simultaneously provide a view of the first software object and the specific 2 - d slice image texture mapped onto the planar surface of the second software object . in another form of the present invention , apparatus and method are provided for determining patient - specific anatomical dimensions using appropriate scanned 2 - d slice image information . the apparatus and method are particularly well suited for determining patient - specific anatomical dimensions with respect to branching anatomical structures , e . g ., vascular structures .