| Virtual scan: Virtopsy detects skull fractures and lesions that conventional post-mortem misses out
During the third year of medical school, students are taken to the police morgue to witness procedures that uncover the cause of death in suspected cases of suicide or homicide.
Valuable information apart, this ensures another thing – after the gruesome sights and smells (fortunately the dead make no sounds), each student becomes well prepared to face any eventuality and is hardened to things that can fell alpha males in feminine faints!
The conventional autopsy is done by slitting open the body cavities from the neck to the pelvis with a long, clean cut. One by one, the organs are examined and parts removed, weighed and sent for toxicological studies.
At the end of it all, the skin is sewn up, the hollow of the empty chest and abdominal cavities hidden from view. Is it then any wonder that most people refuse consent for an autopsy if they have a choice'
Autopsies, however, have a vital role to play in determining the cause of death, and in medical education. As they say, the dead teach the living!
In recent times, forensic scientists have woken up to the need to improve this primitive and ghastly method of mutilating a human body in the name of science. Forensic experts in the University of Bern, Switzerland, have pioneered a new technique of post mortem examination. This is now called Virtopsy, or virtual autopsy.
Using multi-slice CT (Computed Tomography) scanners and MRI (Magnetic Resonance Imaging) machines, the dead body is scanned thoroughly.
Internal body parts are clearly seen, revealing injuries and diseases that would have normally needed a neck-to-pubis incision. In fact, in the Japanese city of Chiba, scientists are using portable CT scanners for head and other injuries and detecting skull fractures and other lesions that conventional post-mortem misses out on.
In bullet injuries and traffic accidents, the CT scanner is used to produce a three-dimensional image of the head. The computer reconstructs exactly where and how the bullet must have hit. In fact, as the Bern group has shown, these images can be animated to give a more real life look, much to the aid of detectives seeking to uncover how death might have occurred.
The implications of this are far ranging, including assessment of vehicle safety and mechanism of accidents to the passengers and pedestrians.
Another new way to avoid the trauma of a post-mortem is by undergoing an angiography with a CT or MRI scan. By this technique, a catheter is passed into the femoral artery at the groin and up to the heart. Radio-opaque dye is injected and the body scanned by the machine.
A thorough exposition of the anatomy of the blood vessels is obtained, leading to clear diagnosis of the mechanism of anatomical injuries as well as the detection of pre-existing diseases like atherosclerosis.
This is the era of minimally invasive surgery. Laparoscopic autopsy is now a real option. The procedure is done by placing high-definition endoscopic video cameras into the body cavities through small keyhole-like cuts.
Thin, long instruments are then inserted for examining the organs, removing parts for special tests, if necessary. This new procedure seems more acceptable, and the consent for such a post-mortem has increased sharply, because it is easier to accept 10 mm and 5 mm cuts on the body of a loved one rather than one measured in feet! In addition, minimally invasive autopsy has been shown to be accurate and obtains as much information as does an open autopsy.
Even unborn foetuses that die in the mother’s womb are now being subjected to autopsy examination, often with ultrasononography correlation.
In a recent article in the Journal of Perinatology (April 2006), S.R. Phadke and V.H. Sankar of Lucknow’s Sanjay Gandhi Post Graduate Institute of Medical Sciences have shown the feasibility of this procedure. Prenatal ultrasound can detect the anomaly causing foetal death.
Then why the need for an autopsy' This is because it detects additional malformations in another one-third of cases. This helps the geneticist in counselling the parents so that they are spared the trauma of subsequent stillbirths and abortions.
Unfortunately, the benefits of virtopsy have not been available in India. The costs of a multi-slice CT scan and MRI, etc. are more than a million dollars apiece.
But if the medical college hospitals use the machines for this purpose, many more cases of “death due to unknown cause” may see the light of truth! In addition, laparoscopic equipment could also be used towards this end.
The country’s unfortunate dead must be indulging in wishful thinking, hoping to be spared the cruel knife of the pathologist!
Dr B Ramana is an advanced laparoscopic surgeon based in Calcutta. He can be contacted at firstname.lastname@example.org