Image Processing Methods for an Exact Reproduction of Unique Waxed Heart Specimens Ivo Wolf, Manuela Makabe, Gerald Greil # , Matthias Thorn, Tal Geva*, Stella Van Praagh*, Richard Van Praagh*, Hans-Peter Meinzer Deutsches Krebsforschungszentrum, Dept. MBI / H0100 Im Neuenheimer Feld 280, 69120 Heidelberg # Universitätskinderklinik Tübingen, Dept. of Pediatric Cardiology Hoppe–Seyler Straße 3, 72076 Tübingen *Children´s Hospital, Harvard Medical School, Dept. of Pathology 300 Longwood Ave, Boston, MA 02115, USA Email: I.Wolf@dkfz.de Summary. Precise knowledge of cardiac anatomy forms the basis for diagnosis and treatment of congenital heart disease. Only a few centers worldwide have access to specialized pathology collections of hearts with congenital malforma- tions. Rare specimens cannot be replaced after loss or damage. To preserve, re- produce, and publish the unique specimens of the Cardiac Registry, Children’s Hospital Boston, for worldwide teaching and research purposes, we have de- veloped the image processing methods described in this paper. The challenge is to preserve all relevant details unaltered in the reproduced models. 1 Introduction Congenital heart defects are one of the most common congenital defects in children and often have a complex anatomic structure. Precise knowledge of cardiac anatomy forms the basis for diagnosis and treatment of congenital heart disease [1]. Static im- ages in books are very limited for the demonstration of complex three-dimensional (3D) relationships. Virtual 3D models, which can be rotated and cut in any plane are much more sufficient for this purpose. However, the perfect teaching and research tool would be a highly accurate reproduction of the original heart. Only anatomic speci- mens provide the best possible way to learn and understand the special relations and dimensions of cardiac malformations. For example, inserting probes into the speci- mens help to clarify the connections between different cavities. Continued use of the specimens lead inevitably to their gradual degeneration. Rare specimens cannot be replaced after loss or damage. As many congenital heart defects can be surgically corrected nowadays, many specimens of the Cardiac Registry are unique, since this collection was established as cardiac surgery was in a very early stage. Additionally, only a few centers worldwide have access to specialized pathol- ogy collections. A method for an exact reproduction of unique specimens is therefore desirable. Conventional methods do not yield the accuracy required to show all details of the essential pathology.