Can computed tomography replace or supplement autopsy?

Enhanced autopsy triage (EA-Triage) in drug-related deaths: integrating quick toxicological analysis and postmortem computed tomography

The objective was to assess the diagnostic accuracy of an enhanced autopsy triage (EA-Triage) setup consisting of postmortem computed tomography (PMCT), simulated quick toxicological analysis (sQTA), external examination, and case information in determining cause of death (COD) in persons with past or current use of illegal drugs (drug-related deaths). Information on drug-related deaths selected for medico-legal autopsy in 2020-2021 at the Department of Forensic Medicine, Aarhus University, Denmark, was analyzed retrospectively. The included cases underwent conventional autopsy, PMCT, and systematic toxicological analysis. A board-certified forensic pathologist, who was blinded to the internal examination and COD from the medico-legal autopsy, determined COD based on the EA-Triage setup. 154 cases with a median age of 40.6 years (range 17-70 years, 82% males) were included. The COD determined by medico-legal autopsy and that determined by EA-Triage matched in 113 cases (73%), including those with an unknown COD. EA-Triage and medico-legal autopsy determined unknown COD in 45 (29%) and 5 cases (3%), respectively. Excluding cases with an unknown COD, EA-Triage predicted COD in 109 cases (71%); of those, 72 (66%) had no unexplained case circumstances or suspicion of a criminal act. In these 72 cases, the CODs determined by EA-Triage and medico-legal autopsy matched in 71 cases (99%), and the sensitivity and specificity for detecting lethal intoxication were 100% and 90%, respectively. EA-Triage showed strong diagnostic accuracy for determining COD in drug-related deaths. This method may be suitable for enhancing preautopsy triage and guiding police investigations at an early stage.

Post-mortem skeletal survey (PMSS) versus post-mortem computed tomography (PMCT) for the detection of corner metaphyseal lesions (CML) in children

OBJECTIVES

Corner metaphyseal lesions (CMLs) are specific for child abuse but challenging to detect on radiographs. The accuracy of CT for CML detection is unknown. Our aim was to compare diagnostic accuracy for CML detection on post-mortem skeletal surveys (PMSS, plain radiography) versus post-mortem CT (PMCT).

METHODS

A 10-year retrospective review was performed at a children's hospital for patients having PMSS, PMCT and histopathological correlation (reference standard) for suspected CMLs. Twenty-four radiologists independently reported the presence or absence of CMLs in all cases in a blinded randomised cross-over design across two rounds. Logistic regression models were used to compare accuracy between modalities.

RESULTS

Twenty CMLs were reviewed for each of the 10 subjects (200 metaphyses in all). Among them, 20 CMLs were confirmed by bone histopathology. Sensitivity for these CMLs was significantly higher for PMSS (69.6%, 95% CI 61.7 to 76.7) than PMCT (60.5%, 95% CI 51.9 to 68.6). Using PMSS for detection of CMLs would yield one extra correct diagnosis for every 11.1 (95% CI 6.6 to 37.0) fractured bones. In contrast, specificity was higher on PMCT (92.7%, 95% CI 90.3 to 94.5) than PMSS (90.5%, 95% CI 87.6 to 92.8) with an absolute difference of 2.2% (95% CI 1.0 to 3.4, p < 0.001). More fractures were reported collectively by readers on PMSS (785) than on PMCT (640).

CONCLUSION

PMSS remains preferable to PMCT for CML evaluation. Any investigation of suspected abuse or unexplained deaths should include radiographs of the limbs to exclude CMLs.

CLINICAL RELEVANCE STATEMENT

In order to avoid missing evidence that could indicate child abuse as a contributory cause for death in children, radiographs of the limbs should be performed to exclude CMLs, even if a PMCT is being acquired.

KEY POINTS

• Corner metaphyseal lesions (CMLs) are indicative for abuse, but challenging to detect. Skeletal surveys (i.e. radiographs) are standard practice; however, accuracy of CT is unknown. • Sensitivity for CML detection on radiographs is significantly higher than CT. • Investigation of unexplained paediatric deaths should include radiographs to exclude CMLs even if CT is also being performed.

Postmortem Computed Tomography Is a Reliable, Reproducible, and Accurate Method in Measuring Body Length

ABSTRACT

Currently, traditional body length measurement at postmortem analysis involves processes, which are susceptible to human error and not reviewable or reproducible in case of data loss. Many facilities are now adopting routine postmortem computed tomography (PMCT) scanning, which provides a permanent and reviewable radiological record of body dimensions. Previous literature has validated the use of PMCT in estimating body and organ weights, but not in body length measurement. This retrospective study aimed to determine whether body length can be accurately and reliably measured when compared with traditional measurements in 50 consecutive adult cases. Our findings revealed that body length measured using PMCT had high intrarater and interrater reliability across different experience levels in raters (Pearson correlation coefficient and interclass correlation: >0.99, P < 0.01). Although body lengths measured using PMCT were significantly shorter (mean, -1.2 cm; 95% confidence interval, -1.75 to -0.65 cm; P < 0.05), it was deemed clinically insignificant and correlated well with those measured at postmortem examination (Pearson correlation coefficient and interclass correlation, >0.97; P < 0.01). While care will need to be taken to ensure the body in the body bag is in reasonable anatomical position for scanning purposes, overall, body length measured uniform PMCT is reliable, reproducible, and accurate.

X-ray analytic microscopy with CT-guided sample extraction to analyze potential projectile fragments in a dead serow

In forensic pathology, it is important to detect and recover as evidence residual metal particles and projectiles when evaluating potential gunshot wounds. This process can be challenging when the bullets are fragmented. This report presents our experience using multiple modalities to analyze the wound of an illegally killed Japanese serow (Capricornis crispus) found in a mountainous region without its head and hind limbs. We performed postmortem computed tomography (PMCT) and necropsy that showed a distant-range gunshot wound of the neck likely created by a centerfire rifle. A postmortem cut through the neck and absent head precluded a complete evaluation. To determine the composition of the metal-like fragments in the neck, sampling and metal analysis were performed in two ways. Samples extracted from the exposed wound surface without CT guidance were analyzed directly using inductively coupled plasma mass spectrometry (ICP-MS). Samples from the bone, muscles, and cervical cord extracted under CT guidance were analyzed using x-ray analytic microscopy (XGT-9000, HORIBA, Kyoto, Japan). In wound surface samples, silicon and iron were detected as the main components on ICP-MS, suggesting that the materials were gravel. The samples taken under CT guidance and analyzed with XGT-9000 revealed that the high-density CT areas were mainly composed of lead. Combining CT-guided sample extraction and XGT-9000 can be useful for retrieving true projectile fragments and avoiding the confusion created by erroneously sampling non-projectile surface materials.

Knowledge and attitudes of Polish prosecutors and general Polish population in regard to post-mortem computed tomography in 2019

Post-mortem computer tomography (PMCT) is an imaging technique that is gaining popularity both worldwide and in Poland. It provides certain benefits in death investigation that a conventional autopsy is not able to, however, it has significant limitations. As PMCT and post-mortem computed angiography (PMCTA) continue to develop in this country, it is critical to become aware what people know and think about these imaging techniques, especially the prosecutors who officially order such examinations to be performed. In 2019, two concurrent surveys were administered to Polish prosecutors and general Polish population, respectively, regarding their current knowledge and opinions on PMCT. The results were collected both online and on paper, and then subjected to analysis. In total, 92 prosecutors and 227 non-prosecutors responded to the survey. The present authors observed that while prosecutors were more likely to have heard of this examination than the general public, their knowledge was often inadequate or incorrect. Conventional autopsy was still held as the gold standard in death investigation. However, a good popular sentiment towards PMCT was shown, and a desire to learn more about it - not just among prosecutors, but among the general public as well. The present authors' recommendation is that more courses and training should be organised for Polish prosecutors to compensate this knowledge gap.