A Study on the Inherent Problems of Post-Mortem X-Rays

Here is an article extract from The Journal of Paediatric Radiology.

Since I am quoting it verbatim, I'll have to leave the crap grammar. We are talking MRI, not grainy old beside x-ray. State-of-the-art stuff,

From a state-of-the-art expert

Introduction

As postmortem imaging becomes more widely used following perinatal and paediatric deaths, the correct interpretation of images becomes imperative, particularly given the increased use of postmortem magnetic resonance imaging. Whilst the diagnostic accuracy of postmortem magnetic resonance imaging, in general, has been shown to be high following specialist interpretation [1], postmortem magnetic resonance imaging is prone to errors made by misinterpretation of normal postmortem changes as pathology, and vice versa.

Practitioners of paediatric and perinatal postmortem magnetic resonance imaging will need expertise in several areas, including knowledge of foetal and congenital abnormalities, the range of perinatal pathologies encountered, awareness of general paediatric radiologic principles and an understanding of specialist MR techniques. As with all new imaging domains, there are several potential pitfalls and errors that can be made during postmortem magnetic resonance imaging interpretation, not only in differentiating the normal postmortem changes from pathology but also recognizing several postmortem changes, which may be incorrectly interpreted as pathology or requiring further investigation. Here, we illustrate postmortem magnetic resonance imaging changes that occur normally after death in fetuses and children, and highlight imaging findings that may confuse or mislead an observer to identifying pathology where none is present, from our experience of more than 500 postmortem magnetic resonance imaging examinations at a specialist children’s hospital.

Normal changes after death

There are changes that occur in a body following death, either in utero or during the interval from death to autopsy, which result in features considered to be normal postmortem changes. Most of these are well recognised by paediatric pathologists on direct visual examination, but the imaging correlates of these need further characterisation.

The main process that occurs following death is termed autolysis, which represents cellular breakdown of body tissues, probably enzyme driven, leading to changes in tissue structure and permeability and fluid redistribution throughout body compartments. The imaging correlations of this are frequently encountered, but the rate at which such changes occur is poorly understood and probably depends upon several factors including antemortem circumstances, age, mode of death, geographical location of death, body storage conditions including temperature and a host of other factors.

In addition to autolysis, simultaneous purification also occurs secondary to bacterial colonisation, which may result in further tissue breakdown and gas formation. In routine paediatric practice, additional factors such as the effects of scavengers and insect activity will be rarely encountered and will not be considered here. Approximate estimates of time of death are often based on these overall changes.

Equally, there has been some debate about the origin of the sometimes significant quantities of gas seen throughout the body on postmortem imaging, with theories regarding gas originating from putrefaction, trauma or resuscitation efforts Although gas in the hepatobiliary system and intravascular gas are often seen at postmortem magnetic resonance imaging these features may not be attributable to any cause (e.g., gas embolus) with any diagnostic certainty.

Acknowledgments

Dr Arthurs is funded by a National Institute of Health Research (NIHR) Clinician Scientist Fellowship. Profs. Taylor and Sebire are funded by NIHR Senior Investigator awards, as well as the Great Ormond Street Children's Charity and the Great Ormond Street Hospital Biomedical Research Centre. The views expressed are those of the authors and are not necessarily those of the National Health Service, the NIHR or the Department of Health

Conflicts of interest

None