Rapid prototyping of medical image data based on distance field concept

This article proposes a Rapid Prototyping (RP) procedure for manufacturing models of organs and tissues from medical imaging data. This RP procedure constitutes four stages: The key task of the first stage is to build the preliminary geometrical model of the target structure. To accomplish this goal, we extract the iso-surface of the target structure at first. Then we discretize the iso-surface into voxels and perform morphological operations upon the iso-surface to remove dangling parts and to fill small holes and gaps. At the second stage, a distance field is generated in the volume space, which encloses the iso-surface. Then a Laplacian filtering is performed to alleviate sharp geometrical features in the distance field. At the third stage, we extract a new iso-surface from the distance field to form the outer surface of the target structure. This iso-surface is the offset surface of the preliminary iso-surface. It forms a hollow solid model of the target object. At the final stage, this solid model is converted into G-codes and is manufactured by using a 3D printer.