Post-mortem CT and MRI: appropriate post-mortem imaging appearances and changes related to cardiopulmonary resuscitation.

Post-mortem cross-sectional imaging in the form of CT and, less frequently, MRI is an emerging facility in the evaluation of cause-of-death and human identification for the coronial service as well as in assisting the forensic investigation of suspicious deaths and homicide. There are marked differences between the radiological evaluation and interpretation of the CT and MRI features of the live patient (i.e. antemortem imaging) and the evaluation and interpretation of post-mortem CT and MRI appearances. In addition to the absence of frequently utilized tissue enhancement following intravenous contrast administration in antemortem imaging, there are a number of variable changes which occur in the tissues and organs of the body as a normal process following death, some of which are, in addition, affected significantly by environmental factors. Many patients and victims will also have undergone aggressive attempts at cardiopulmonary resuscitation in the perimortem period which will also significantly alter post-mortem CT and MRI appearances. It is paramount that the radiologist and pathologist engaged in the interpretation of such post-mortem imaging are familiar with the appropriate non-pathological imaging changes germane to death, the post-mortem interval and cardiopulmonary resuscitation in order to avoid erroneously attributing such changes to trauma or pathology. Some of the more frequently encountered radiological imaging considerations of this nature will be reviewed.