SummaryBackgroundEngland and Wales have one of the highest frequencies of autopsy in the world. Implementation of post-mortem CT (PMCT), enhanced with targeted coronary angiography (PMCTA), in adults to avoid invasive autopsy would have cultural, religious, and potential economic benefits. We aimed to assess the diagnostic accuracy of PMCTA as a first-line technique in post-mortem investigations.MethodsIn this single-centre (Leicester, UK), prospective, controlled study, we selected cases of natural and non-suspicious unnatural death referred to Her Majesty's (HM) Coroners. We excluded cases younger than 18 years, known to have had a transmittable disease, or who weighed more than 125 kg. Each case was assessed by PMCTA, followed by autopsy. Pathologists were masked to the PMCTA findings, unless a potential risk was shown. The primary endpoint was the accuracy of the cause of death diagnosis from PMCTA against a gold standard of autopsy findings, modified by PMCTA findings only if additional substantially incontrovertible findings were identified.FindingsBetween Jan 20, 2010, and Sept 13, 2012, we selected 241 cases, for which PMCTA was successful in 204 (85%). Seven cases were excluded from the analysis because of procedural unmasking or no autopsy data, as were 24 cases with a clear diagnosis of traumatic death before investigation; 210 cases were included. In 40 (19%) cases, predictable toxicology or histology testing accessible by PMCT informed the result. PMCTA provided a cause of death in 193 (92%) cases. A major discrepancy with the gold standard was noted in 12 (6%) cases identified by PMCTA, and in nine (5%) cases identified by autopsy (because of specific findings on PMCTA). The frequency of autopsy and PMCTA discrepancies were not significantly different (p=0·65 for major discrepancies and p=0·21 for minor discrepancies). Cause of death given by PMCTA did not overlook clinically significant trauma, occupational lung disease, or reportable disease, and did not significantly affect the overall population data for cause of death (p≥0·31). PMCTA was better at identifying trauma and haemorrhage (p=0·008), whereas autopsy was better at identifying pulmonary thromboembolism (p=0·004).InterpretationFor 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.FundingNational Institute for Health Research.

Post-mortem computed tomography with coronary angiography (PMCTA) could have a role in the investigation of sudden natural death. This study assesses the accuracy of targeted coronary PMCTA, using both air and iodinated contrast media, to provide sensitivity and specificity for critical stenosis (CS) on a segmental basis, based on a gold standard of 3-5 mm serial sections of the coronary arteries using macroscopic and histological techniques. Assessment of stenosis at 1 mm intervals on PMCTA was compared with the data from pathological analysis. Stenosis was defined as "critical" when the stenotic region reaches ≥75 %. Regions were defined every 20 mm or by a clear change in stenosis. Discrepancies were defined as significant if only one test showed CS. Five cases with 25 vessels with 124 regions were assessed. PMCTA was unable to identify plaque hemorrhage or dissection (but this was normally associated with CS). Eighteen segments had significant discrepancies, giving a sensitivity and specificity of 50 and 91.5 %. When an alternative gold standard was constructed by excluding regions beyond a CS (five cases), taking PMCTA as correct where a heavily calcified vessel opens under contrast injection (four cases), and correcting for misregistration of distance (one case), the sensitivity rose to 85.7 %. There was complete agreement when the right or left coronary arteries are assessed as a whole. This study shows that PMCTA is not a perfect replacement for histological examination of coronary vessels, but may have a role in routine post-mortem investigation.

In England and Wales there is a conflict between the law and advice from regulatory bodies in relation to the sampling of human tissue for histological examination following medico-legal post-mortem examinations. Considering the results of previous publications, we performed a specific study to investigate the role of histology in determining the cause of death in cases at a forensic unit. A retrospective study of 500 adult forensic cases was performed. Cases were categorized by the role the histological examination played in determining a cause of death and its contributory factors. Furthermore, cause of death, manner of death, organ systems involved, and discrepancies were assessed. Of the 500 cases, histology was undertaken in 287 cases (58 %). Microscopic examination provided the cause of death in 2 % of cases where histology had been undertaken, and it added to the cause of death in 8 %. In 61 % of cases microscopy confirmed the macroscopic findings, and in 30 % it did not influence the medical cause of death. Histological examination of all organs in all forensic cases for the purpose of providing a medical cause of death is not supported. Practice guidance should be adjusted to reflect that, while histological examination is essential in certain circumstances, the decision to retain material for histology should be made on a case by case basis at the pathologist's discretion.

Bodies found immersed in water can pose difficulties to the investigating authorities. Pathologists may be assisted with the diagnosis by the use of tests such as the analysis for diatoms or the levels of strontium in the blood, although there is a recognised level of uncertainty associated with these tests. Recent work from Japan has shown that using molecular approaches, most recently real-time polymerase chain reaction (PCR) assays with TaqMan probes for bacterioplankton, it is possible to undertake rapid, less laborious, high throughput tests to differentiate freshwater from marine bacterioplankton and in doing so provide a molecular diagnostic test to assist in the diagnosis of drowning. We report the experiences of a United Kingdom forensic pathology unit in the use of this PCR based system for the diagnosis of drowning. We applied this technique to 20 adult and child cadavers from 4 bath, 12 freshwater, 2 brackish and 2 salt water scenes both from within the United Kingdom and abroad. Drowning was concluded to be the cause of death in 16 of these 20 cases and the PCR method supported this conclusion in 12 of these 16 cases. The PCR did not provide evidence of drowning in the four cases where death was from other causes. We illustrate that this PCR method provides a rapid diagnostic supportive test for the diagnosis of drowning that can be applied to United Kingdom autopsy practice.