Forensic Pathology

Virtopsy; Advancements in Forensic Imaging

Seth Dominique

Jackson Community College

Abstract

Virtual autopsy is a rapidly advancing field in medical imaging. It can provide many improvements in the way we examine the deceased. Eventually it might completely take the place of tradional autopsies. It will change the fields of radiology and pathology forever.

Advancements in Forensic Imaging

Virtual autopsy is not something you would think of in the realm of medical imaging. The majority of images in the past have been done on the living, but it is just that “the past.” The people of Virtopsy are working hard to ensure that. Their system of forensic imaging is taking the traditional autopsy and relegating it to a secondary option.

Virtopsy is based in Bern, Switzerland. Dr. Michael Thali heads the project.

The concept behind all of this is simple; allow a machine to do the work that a person has been doing for years. The execution of this Idea is where it gets a little complicated. It uses multi-slice computed tomography (MSCT), magnetic resonance imaging (MRI), and a three-dimensional surface scanner. The MSCT images are stacked to create a 3-D view of the body. MRI is used where it is best on the soft tissues of the body. Surface scanning allows the 3-D image created by the CT to have a skin. Using all of these technologies together makes for an impressive and accurate view of the human body.

Forensic imaging is not a new tool. It has been in use in one form or another for as long as there has been diagnostic imaging. It is only recently with the advent of three-dimensional imaging that a truly useful tool could be applied. “In the old days, we had no idea what plane a bullet was laying in without taking a series of X-rays,” said Craig Mallak M.D. an Armed Forces Institute of Pathology (AFIP) medical examiner. “Now we run the body through a CT scanner and we know exactly where to look for the projectile.”

One of the main advantages to doing a virtual autopsy is none of the forensic evidence is destroyed. In a normal autopsy the body is sliced open forever altering the way in which the data can be obtained. In court proceedings this is extremely valuable with victims of blunt trauma, such as a motor vehicle accident. When a scull fracture is autopsied the skin is removed allowing the skull fragments to shift. Using a CT scanner can allow you to create a permanent record of the injury. This ensures that the proper object that made the wound is identified. In most cases this can allow for an autopsy to be avoided all together.

Establishing the time of death is problem that may be solved through the use of MR spectroscopy. The current standard for cases where the victim has already reached room temp is to evaluate the state of decay. Environmental considerations play a huge role in the rate. Accurate findings are often based on the experience of the forensic pathologist. A better way to determine the time of death is to examine the metabolite concentrations in the brain tissue. The metabolites appear at a steady rate as the brain tissue decays. That is why they can provide an accurate postmortem interval.

In a mass causality such as the tsunami in Indonesia, or in Hurricane Katrina the use of Virtopsy is a time saving tool. It can be used to determine whether or not an individual is in need of an autopsy. A MRI can pinpoint the water. In most cases the position of the water and the amount can either confirm or rule out drowning as the primary cause of death. This also aids in the record keeping process, as an easy way to establish a permanent record for reevaluation of the procedure later.

The cultural aspects are something that is not medical, but still deserve some attention. Some religions such as Judaism, Jehovah’s witnesses, and the fastest growing religion in the world; Islam prohibit the body being disturbed after death unless required by law. Virtopsy offers a non-invasive way to conduct a post-mortem examination on an individual who might otherwise not receive one.

The limitations that ensure that ensure that the use of a scalpel will continue for some time are few but significant. One is post mortem angiography. When done on an individual who has recently expired the process works fine. The problem occurs once tissue decay has started. The contrast will not flow into spots where a rupture