Targeted coronary post-mortem CT angiography, straight to the heart
Authors: Rick R van Rijn, Peter M Leth
Journal: The Lancet (2017)

Soon after the discovery of x-rays in November, 1895, by Wilhelm Conrad Röntgen, the first post-mortem radiographs were obtained; one example being the post-mortem angiography done by Haschek and Lindenthal in January, 1896.1Dutto O Fotografi del sistema arterioso ottenute con raggi Röntgen.Rendic Reale Acad Lincei. 1896; 5 (in Italian).: 129Google Scholar However, it took the pioneering work of Richard Dirnhofer and Michael Thali with their Virtopsy group to regain wider attention for post-mortem radiology and more specifically post-mortem CT (PMCT).2Thali MJ Yen K Schweitzer W et al.Virtopsy, a new imaging horizon in forensic pathology: virtual autopsy by postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI)—a feasibility study.J Forensic Sci. 2003; 48: 386-403Google Scholar In the past decades, substantial progress has been made, although the main focus of attention has been on adult forensic PMCT. PMCT can have an effect on the diagnosis of the manner and cause of death, and it certainly has limitations. Most of these limitations are related to the fact that the person is no longer alive and thus ventilation and circulation have stopped. This fact also implies that a normal contrast-enhanced PMCT scan, which clinically is routinely acquired, is not possible. To overcome this limitation, the use of whole body PMCT angiography (wbPMCTA) or focused PMCT angiography (fPMCTA) has been advocated.3Grabherr S Grimm J Dominguez A Vanhaebost J Mangin P Advances in post-mortem CT-angiography.Br J Radiol. 2014; 87: 20130488Google Scholar A lot of effort has been put into the development, use, and validation of multiphase wbPMCTA and good results have been shown with a dedicated wbPMCTA system.4Grabherr S Grimm JM Heinemann A Atlas of postmortem angiography. Springer International Publishing, Cham2016Google Scholar, 5Grabherr S Doenz F Steger B et al.Multi-phase post-mortem CT angiography: development of a standardized protocol.Int J Legal Med. 2011; 125: 791-802Google Scholar In the Lancet, Guy N Rutty and colleagues6Rutty GN Morgan B Robinson C et al.Diagnostic accuracy of post-mortem CT with targeted coronary angiography versus autopsy for coroner-requested post-mortem investigations: a prospective, masked, comparison study.Lancet. 2017; (published online May 24)http://dx.doi.org/10.1016/S0140-6736(17)30333-1Google Scholar report a prospective study about the value of PMCTA in natural sudden death. For this post-mortem imaging study, the primary outcome for large prospective series was the accuracy of cause of death, if identifiable on PMCTA compared with the autopsy (which they class as gold standard). The radiologists reporting the PMCTA, which included a precontrast total body PMCT, had access to a full report consisting of external examination findings and additional medical history. If requested, toxicology and biochemistry results were given. This approach has previously been named a minimal invasive autopsy.7Thayyil S Sebire NJ Chitty LS et al.Post mortem magnetic resonance imaging in the fetus, infant and child: a comparative study with conventional autopsy (MaRIAS Protocol).BMC Pediatr. 2011; 11: 120Google Scholar In all these cases in Rutty and colleagues' study, the frequency of PMCTA error was 6% (12 of 193 cases). Secondary endpoints were, among others, success of procedure (204 of 241, 85%) and identification of a cause of death (193 of 210, 92%). Therefore, the authors show that, in the English coronial system, 92% of autopsies could be avoided. This approach would not affect overall population cause of death data, nor would cases of substantial trauma (unnatural cause of death) be missed. How this would affect clinical pathology services in other parts of the world is unclear. This study by Rutty and colleagues adds weight to the use of PMCTA because it clearly shows the feasibility of the technique and the potential effect on daily pathological routine. The way this study has been designed is reminiscent of the highly acclaimed MaRIAS study,7Thayyil S Sebire NJ Chitty LS et al.Post mortem magnetic resonance imaging in the fetus, infant and child: a comparative study with conventional autopsy (MaRIAS Protocol).BMC Pediatr. 2011; 11: 120Google Scholar and we expect that it could have a similar effect in the specialty of post-mortem imaging. The success of PMCTA in up to 85% of cases, after a learning curve, implies that it is feasible to use in a specialised setting. The question is whether this success would also be attained in a normal setting, where a larger group of radiological technicians would be doing the PMCTA scans. A second drawback, as acknowledged by Rutty and colleagues, is the fact that PMCTA was reported by three examiners without any time constraint, which would not be feasible in a normal clinical setting. The study by Rutty and colleagues focused on cause of death and individual diagnoses. Many important forensic questions concern injury mechanisms, not the individual diagnosis, and more research in this area is needed. Finally, it would have been interesting to know if a limited autopsy or an autopsy limited to percutaneous image-guided biopsies would have reduced the need for autopsies even further. Nevertheless, this study shows that PMCTA is a robust and reliable technique, which, if access to a CT scanner is available, can be implemented without much financial investment in daily pathological practice. The rapid development of post-mortem imaging will continue, and it is possible that methods other than CT, such as MRI, will become increasingly important. Future research should be aimed at determining which combination of post-mortem investigation methods are best suited for specific purposes, taking into account the aim of the investigation and securing optimal use of the available resources. Some difficult cases might require an invasive autopsy that follows an enhanced algorithm with extensive histological and genetic testing, whereas other cases might be satisfactorily investigated with imaging techniques. We declare no competing interests. Diagnostic accuracy of post-mortem CT with targeted coronary angiography versus autopsy for coroner-requested post-mortem investigations: a prospective, masked, comparison studyFor most sudden natural adult deaths investigated by HM Coroners, PMCTA could be used to avoid invasive autopsy. The gold standard of post-mortem investigations should include both PMCT and invasive autopsy. Full-Text PDF Open Access