Artifactual aortic dissection as a result of post-mortem CT angiography

An 82-year-old woman who died unexpectedly at home was admitted to our institute for investigation into her cause of death. Extensive subarachnoid hemorrhage was identified on the admission post-mortem computed tomography (PMCT) scan. Subsequent post-mortem computed tomography angiography (PMCTA) utilizing embalming principles and equipment identified leak of contrast from the right middle cerebral artery indicative of ruptured aneurysm and this was confirmed at autopsy. Unexpectedly after autopsy, PMCTA review revealed a large intimal flap indicative of apparent extensive aortic dissection arising from the tip of the infusion cannula in the left femoral artery to the ascending aorta, rupturing into the pericardial sac. This was not in keeping with the admission PMCT and was not detected at autopsy, although aortic atherosclerosis was present. This finding mirrors a similar artifact recently described in the literature secondary to embalming. In this case, it appeared to be an artifact of the PMCTA technique due to mechanical disruption of the arterial wall at the point of cannulation with flow of contrast solution into both true lumen and aortic wall creating a false lumen. With increasing use of post-mortem imaging to assist in medico-legal death investigations, it is imperative that practitioners be aware of and take into consideration the post-mortem changes and artifacts that can be caused by and detected on such imaging. In addition, it is important that all cases undergoing PMCTA have a preliminary PMCT for comparison and that all imaging findings are presented to the pathologist prior to autopsy for correlation at dissection.