Who Was The Murderer?

This example shows a heart that sustained a perforating laceration at it’s base by a broken rib in a victim of a car accident (left, see arrow). A signal deviation from normal with a similar location, similar size and similar shape could now be shown to be present in reconstructed CT images (3D reconstruction, right, see arrow).

Background
Wolf Schweitzer, a forensic pathologist from the Institute of Legal Medicine at the University of Bern, Switzerland, now at the Institute of Legal Medicine at the University of Zuerich, Switzerland, is developing new techniques to answer this question. One approach is to employ medical imaging modalities like CT and MR in order to examine victims of violent death. The advantage of carrying out such an examination before an autopsy is that reconstructions from digital images can be performed repeatedly in any manner without the risk of destroying a potential finding. Such reconstruction requires dedicated software allowing for freely adjustable and reproducable image reconstruction from a 3D image dataset. Within an object-oriented model termed "Pink box", typical reconstruction types which are needed in such a software are derived from classical autopsy techniques.

Requirements
Wolf Schweitzer, supported by three colleagues with a background of informatics, image analysis in remote sensing and theoretical physics, created an object-oriented model termed "Pink Box" back in 1998 in Melbourne, Australia. The motivation for adding CREASO manpower to a step-wise implementation of parts of this "Pink Box" model within IDL was to

• optimize use of IDL's capabilities
• develop approaches for special requirements like semi-opaque 3D volume visualization
• answer special questions about IDL
• add CREASO's knowledge about 3D image reconstruction into this project.

The CREASO Solution
A two-day coaching took place at CREASO, supported by the Gebert Rüf Stiftung (Switzerland) and the Institute of Legal Medicine of the University in Bern. More than10 topics were discussed during this event. This included fundamentals like how to use pointers and objects in IDL programming as well as special topics from medical imaging like grayscale windowing or extraction of arbitrary slices from anisotropic image datasets. Ready-to-use solutions were developed where possible. Possible approaches were discussed for more complex questions.

The Benefits
"Our cooperation was a complete success for me," says Wolf Schweitzer. "I was surprised about how effectively my questions were answerded during these two days. My software and my understanding of IDL was substantially improved, allowing me to concentrate on my research and to improve the model we work with much more effectively. The CREASO coaching concept allows to add highly specialized, well trained and effective manpower to this project again, whenever it will be needed."

References:
(1) Schweitzer W, Schaepman M, Ith M, Bruegger K, Thali M, Doernhoefer T, Tiefenthaler K, Scheurer E, Vock P, Boesch C, Dirnhofer R (2001) Evidential value of Post Mortem MRI in Forensic Pathology. Proceedings, SPIE meeting Medical Imaging 2001, Feb 18-24 in San Diego, USA.

(2) Schweitzer W, Yen K, Thali M, Scheurer E, Vock P, Bösch C, Ith M, Sonnenschein M, Brügger K, Spielvogel E, Königsdorfer U, Dorn R, Dirnhofer R (2001) Virtopsy: Dokumentation von Herzbefunden bei 35 Autopsien im Vergleich mit CT und MRI. 80. Jahrestagung DGRM Interlaken, September 2001.