ABSTRACT
Size-and posture-adjustable phantoms are computational models of the human body that have the ability to automatically or semiautomatically deform in order to de ne various organ shapes and volumes, as well as body postures. This type of deformable phantoms was found to be easier to develop with Boundary REPresentation (BREP) geometry de nition methods in the form of either nonuniform rational B-splines (NURBS), polygon mesh, or a combination of both.1-5 Compared to voxel models, BREP models are better suited for geometry deformation and adjustment because a richer set of computerized operations can be utilized. These operations include extrusion, chamfering, blending, drafting, shelling, and tweaking. One of the most attractive applications of adjustable phantoms is their ability to “morph” into an existing reference phantom or into a new anatomy of a worker or patient for whom their does not exist suf cient whole-body image data.
