Interpretation of postmortem head computed tomography for non-traumatic in-hospital deaths by non-radiologists: a preliminary study

Purpose
Postmortem computed tomography (PMCT) has recently become important to clarify the cause of death in forensic medicine. It has also been proven to be useful for in-hospital deaths to a certain extent when interpreted by radiologists. However, accuracy of the interpretations of PMCT by non-radiologists remains to be elucidated. Nevertheless, they are often required to write death certificates based on the findings of PMCT in the absence of radiologists in Japan. We compared the interpretations of postmortem head CT (PMCT-H) by non-radiologists with the autopsy findings.

Methods
This study included 13 patients who underwent both brain dissection at autopsy and PMCT between June 2011 and December 2014. All cases were non-traumatic in-hospital deaths. Interpretation of PMCT was performed by the clinicians in charge of the patients, not by radiology experts.

Results
The patients were first examined with PMCT and then autopsies were performed. Ten out of 13 cases were confirmed to have no lesions in the cranial cavity by both PMCT-H and autopsy. Two cases were diagnosed with intracranial hemorrhage (intracerebral and/or subarachnoid hemorrhage) and one with recurrent malignant lymphoma by both the clinicians and the pathologists. Intracranial hemorrhages were thought to be the direct causes of mortality of the two patients, and recurrent malignant lymphoma was considered to be one of the cardinal findings of the cancer death. There were no discrepancies between PMCT-H and autopsy findings.

Conclusions
The interpretations of PMCT-H by non-radiologists were completely the same as the autopsy findings regarding the non-traumatic in-hospital deaths in this study. It is premature to draw a definitive conclusion at present, but PMCT-H might be as effective as autopsy not only for those lesions described above but also for no remarkable changes in the brain. There has been no report on such a comparison. We believe further verification of the validity of interpretation of PMCT by non-radiologists is worthwhile in terms of death certificates made out in the absence of radiology experts and pathologists.