Anatomical structures are reconstructed from patient-specific medical images (CT computed tomography or magnetic resonance imaging, MRI). It depends primarily on an accurate representation of the structures of a patient. Therefore these discrete surface models (so-called meshes, triangulations) are used in practice, as these are not only geometrically flexible but also can be stored efficiently and displayed.
In CAD systems however 3D objects are described as smooth parametric surfaces(non-uniform rational B-Splines, NURBS). It is important for the storage and processing, to keep the complexity of NURBS low. In order to integrate anatomical structures in CAD systems, meshes need to be converted to NURB surfaces. Existing CAD systems often produce anatomical structures that :
(i.) often require too much memory for efficient processing or
(ii.) are inconsistent, and therefore require manual post-processing.
The goal of this project is to conduct a feasibility study of available methods and software that assist in the automatic conversion of meshes into NURBS for anatomical structures and develop a prototype implementation.
Quadrilateral Patch of the triangulated Femur.