A Computer-Aided Design System for Segmentation of Volumetric Images

Image segmentation is an important component of any image analysis system. In medical imaging, it is essential that an image is accurately segmented so that different measurements about the region are accurately determined. In this paper, the idea of using a computer-aided design system to effectively revise the result of an automatically determined segmentation was introduced. In the proposed system, a RaG surface is fitted to voxels representing a 3D region by the least-squares method. The surface and the original volumetric image are then overlaid and the surface is interactively revised until the desired segmentation is achieved.

The system provides the option of using the output of an automatically obtained segmentation as the input or manually creating an initial segmentation by selecting a number of 3D points in the given image volume. In the latter case, an initial surface is created from the points and overlaid with the image. The user can then observe the image data and revise the surface to a desired shape. Because a region of interest is represented by a parametric surface, the surface may be sent to a computer-aided manufacturing system for construction of an actual 3D model of the region.