1 - Implicit Surfaces for Semi-automatic Medical Organ Reconstruction

Abstract

This chapter discusses the implicit surfaces for semiautomatic medical organ reconstruction. A new method for reconstruction with implicit surfaces generated by skeletons is presented. Local control on the reconstructed shape due to a local field function, which enables the definition of local energy terms associated with each skeleton is described. This leads to a much more efficient skeleton subdivision process, since one gets a robust criterion telling which skeleton should be divided next. The knowledge of the normal vectors at the data points is not needed. The method works as a semiautomatic process and the user can visualize the data, initially position some skeletons due to an interactive implicit surfaces editor, and further optimize the process by specifying several reconstruction windows, that slightly overlap, and where surface reconstruction follows a local criterion. It is found that if needed, different precisions of reconstruction can be defined in each window. The shapes to reconstruct can be of any topology and geometry, and for instance include holes and branchings. The reconstruction experiments from noisy medical data, for which scattered points are arranged in nonuniform repartition, are shown.