Landmark-Based 3D Elastic Registration of Pre- and Postoperative Liver CT Data

Abstract. The qualitative and,quantitative comparison of pre- and postoperative image data is an important possibility to validate com- puter assisted surgical procedures. Due to deformations after surgery a non-rigid registration scheme,is a prerequisite for a precise compari- son. Interactive landmark-based schemes are a suitable approach. In- corporation of a priori knowledge,about the anatomical structures to be registered may,help to reduce interaction time and improve accu- racy. Concerning pre- and postoperative CT data of oncological liver resections the intrahepatic vessels are suitable anatomical structures. In addition to using landmarks at vessel branchings, we here introduce quasi landmarks at vessel segments with anisotropic localization precision. An experimental comparison of interpolating thin-plate splines (TPS) and Gaussian elastic body splines (GEBS) as well as approximating GEBS on both types of landmarks is performed.