Michael Thali, M.D., a board-certified forensic pathologist and project manager for Virtopsy at the University, presented the crime and accident scene investigation technology at the 89th Scientific Assembly and Annual Meeting of the Radiological Society of North America (RSNA), recently held in Chicago.
"The virtual autopsy does not destroy key forensic evidence which may be damaged during a classic autopsy", stated Dr. Thali, who also has specialized training in radiology. "It can also be used in cultures and situations where autopsy is not tolerated by religion, such as in the traditional Jewish faith, or is rejected by family members. Some people do not like the idea of autopsy."
Virtual autopsy combines computed tomography (CT) and magnetic resonance (MR) imaging. The CT images provide information about the general pathology of the body and can generate detailed information about trauma injuries. MR imaging is used to focus on specific areas of the body, providing details about soft tissue, muscles and organs. To determine the time of death, Virtopsy uses MR spectroscopy, a technique that measures metabolites in the brain emerging during post-mortem decomposition.
In cases where a weapon is used, 3D surface scanning, first used by the auto industry to develop and analyse auto parts, documents the surface of the body. Using a computer-aided design programme, investigators can then compare the virtual model of an injury with the 3D image of a simulation created by using a similar-type weapon.
"It's then possible to merge all of this information from the body's inside and outside into one data set on the computer", Dr. Thali explained. "We now have 3D, non-subjective information that can easily be presented in court without showing graphic, horrible images that may shock people."
If necessary, data can be sent via compact disc or e-mail to another forensic pathologist for a second opinion, and stored for years on a computer. But virtual autopsy is expensive and right now there are graphic limitations in providing full-colour information, according to Dr. Thali. Also, virtual autopsy cannot yet be used for a post-mortem angiography, which may reveal important information about the person's cardiovascular system at the time of death.
"It may be another 10 to 15 years before this method is accepted, but we've already started to present some of our data in the Swiss court system", Dr. Thali stated. "I believe that forensic radiology will be a new science in the future." Dr. Thali's collaborators and co-authors of this education exhibit are Richard Dirnhofer, M.D., and Peter Vock, M.D.