Common Postmortem Computed Tomography Findings Following Atraumatic Death: Differentiation between Normal Postmortem Changes and Pathologic Lesions

Implications of intracochlear decomposition gas formation in non-putrefied cadavers

Introduction

Postmortem computed tomography (pmCT) prior to forensic autopsy has become increasingly important in recent decades, especially in forensic documentation of single injuries, injury patterns, and causes of death. Postmortem decomposition gas formation can also be detected in pmCT scans, which might affect cochlear implant research in postmortem human temporal bones (TBs).

Material and methods

Fifty non-putrefied hanging fatalities within a 2-year period (January 2017 to December 2019) were included with 100 TBs. Each body underwent whole-body pmCT prior to forensic autopsy. PmCT scans were analyzed with respect to the presence of intracochlear gas despite the lack of putrefaction at autopsy by an experienced fellow neurotologist.

Results

PmCT revealed gas formation in two individuals despite the lack of head trauma and putrefaction at postmortem examination and autopsy. Both individuals showed enclosed gas in the vestibule and the cochlea on both sides.

Discussion

Intracochlear gas formation, most likely related to decomposition, may occur despite the lack of putrefaction at postmortem examination and autopsy and can be detected by pmCT. This finding seems to be rather rare in non-traumatic death cases but might affect cochlear pressure research in postmortem human TB.

Cutoff CT value can identify upper gastrointestinal bleeding on postmortem CT: Development and validation study

This study aimed to establish the diagnostic criteria for upper gastrointestinal bleeding (UGIB) using postmortem computed tomography (PMCT). This case-control study enrolled 27 consecutive patients with autopsy-proven UGIB and 170 of the 566 patients without UGIB who died in a university hospital in Japan after treatment and underwent both noncontrast PMCT and conventional autopsy between 2009 and 2020. Patients were randomly allocated to two groups: derivation and validation sets. Imaging findings of the upper gastrointestinal contents, including CT values, were recorded and evaluated for their power to diagnose UGIB in the derivation set and validated in the validation set. In the derivation set, the mean CT value of the upper gastrointestinal contents was 48.2 Hounsfield units (HU) and 22.8 HU in cases with and without UGIB. The optimal cutoff CT value for diagnosing UGIB was ≥27.7 HU derived from the receiver operating characteristic curve analysis (sensitivity, 91.7%; specificity, 81.2%; area under the curve, 0.898). In the validation set, the sensitivity and specificity in diagnosing UGIB for the CT cutoff value of ≥27.7 HU were 84.6% and 77.6%, respectively. In addition to the CT value of ≥27.7 HU, PMCT findings of solid-natured gastrointestinal content and intra/peri-content bubbles ≥4 mm, extracted from the derivation set, increased the specificity for UGIB (96.5% and 98.8%, respectively) but decreased the sensitivity (61.5% and 38.5%, respectively) in the validation set. In diagnosing UGIB on noncontrast PMCT, the cutoff CT value of ≥27.7 HU and solid gastrointestinal content were valid and reproducible diagnostic criteria.

Essence of postmortem computed tomography for in-hospital deaths: what clinical radiologists should know

Postmortem computed tomography (CT) is an essential tool for investigating the causes of death. Postmortem CT has characteristic imaging findings and should not be interpreted in the same manner as clinical antemortem images. In analyzing the cause of death in in-hospital death cases using postmortem images, it is crucial to understand early postmortem and post-resuscitation changes. In addition, it is essential to understand the limitations of diagnosing the cause of death or significant pathology relating to death on non-contrast-enhanced postmortem CT. In Japan, there has also been social demand to establish a system for postmortem imaging at the time of death. To facilitate such a system, clinical radiologists should be prepared to interpret postmortem images and assess the cause of death. This review article provides comprehensive information regarding unenhanced postmortem CT for in-hospital death cases in daily clinical practice in Japan.

A clear presentation of intracranial hypostasis on PMCT

Intracranial hypostasis is a common postmortem change evident on postmortem CT (PMCT), but can be readily misinterpreted as subdural hematoma by inexperienced physicians. Although PMCT is necessarily lacking contrast enhancement, we reconstructed hypostatic sinuses into three-dimensional images resembling the results of in vivo venography. This simple methodology facilitates easy recognition of intracranial hypostasis.

Technical and interpretive pitfalls of postmortem CT: Five examples of errors revealed by autopsy

Image acquisition of dead bodies, particularly using postmortem computed tomography (PMCT), has become common in forensic investigations worldwide. Meanwhile, in countries such as Japan which have an extremely low rate of autopsy, PMCT is being increasingly used in the clinical field to certify the cause of death (COD) without performing an autopsy or toxicological tests, even in cases of unnatural death. Additionally, these PMCT images are predominantly interpreted by clinical personnel such as emergency physicians or clinicians who are not trained in PMCT interpretation and who work for the police, that is, the so-called police doctors. Many potential pitfalls associated with the use of PMCT have been previously described in textbooks and published papers, including the pitfalls of not performing a complete forensic pathology investigation, and the use of physicians without appropriate PMCT training to interpret PMCT and direct death investigation and certification. We describe five examples in which apparent misdiagnosis of COD based on PMCT misinterpretation was revealed by autopsy. Here are the five examples of errors: (1) Postmortem changes were misinterpreted as COD, (2) resuscitation effects were misinterpreted as COD, (3) COD was determined after an incomplete examination, (4) fatal findings caused by external origin were wrongly interpreted as 'of internal origin' based on PMCT, and (5) non-fatal findings on PMCT were wrongly interpreted as fatal. Interpretation of PMCT by appropriately trained physicians and an accompanying complete forensic investigation, including autopsy when indicated, is necessary to prevent significant errors in COD determination and related potential adverse medicolegal consequences.

Delayed cerebral enhancement on post-mortem computed tomography due to residual contrast medium administered shortly before death

Postmortem computed tomography (CT) is currently a well-known procedure and helps in postmortem investigations. In this case report, we report a unique postmortem CT finding: delayed cerebral enhancement associated with the antemortem infusion of contrast medium. A 72-year-old female lost consciousness at a restaurant and was taken to a hospital in an ambulance. Despite resuscitation efforts, she died of hypoxic–ischemic encephalopathy caused by cardiac arrest. About 6 h before her death, she underwent enhanced antemortem CT of the head. No abnormal enhancement was observed in the cerebral parenchyma. Then, 11 h after her death, she underwent unenhanced postmortem CT, which showed bilateral hyperdense caudate nucleus and putamina, due to residual iodinated contrast medium, in addition to other characteristic findings of hypoxic–ischemic encephalopathy. The mechanism underlying this phenomenon could be the destruction of the blood–brain barrier, and/or selective vulnerability, due to hypoxic–ischemic changes in the gray matter. Enhancement of basal ganglia on postmortem CT due to antemortem infusion of iodinated contrast medium might suggest hypoxic–ischemic encephalopathy, which should be noted in postmortem CT interpretations.

Use of post-mortem chest computed tomography in Covid-19 pneumonia

Background and aim

COVID-19 is an extremely challenging disease, both from a clinical and forensic point of view, and performing autopsies of COVID-19 deceased requires adequately equipped sectorial rooms and exposes health professionals to the risk of contagion. Among one of the categories that are most affected by SARS-Cov-2 infection are the elderly residents. Despite the need for prompt diagnoses, which are essential to implement all isolation measures necessary to contain the infection spread, deceased subjects in long-term care facilities are still are often diagnosed post-mortem. In this context, our study focuses on the use of post-mortem computed tomography for the diagnosis of COVID-19 infection, in conjunction with post-mortem swabs. The aim of this study was to assess the usefulness of post-mortem whole CT-scanning in identifying COVID-19 pneumonia as a cause of death, by comparing chest CT-findings of confirmed COVID-19 fatalities to control cases.

Materials and methods

The study included 24 deceased subjects: 13 subjects coming from long-term care facility and 11 subjects died at home. Whole body CT scans were performed within 48 h from death in all subjects to evaluate the presence and distribution of pulmonary abnormalities typical of COVID-19-pneumonia, including: ground-glass opacities (GGO), consolidation, and pleural effusion to confirm the post-mortem diagnosis.

Results

Whole-body CT scans was feasible and allowed a complete diagnosis in all subjects. In 9 (69%) of the 13 cases from long-term care facility the cause of death was severe COVID 19 pneumonia, while GGO were present in 100% of the study population.

Conclusion

In the context of rapidly escalating COVID-19 outbreaks, given that laboratory tests for the novel coronavirus is time-consuming and can be falsely negative, the post-mortem CT can be considered as a reliable and safe modality to confirm COVID-19 pneumonia. This is especially true for specific postmortem chest CT-findings that are rather characteristic of COVID-19 fatalities.

Characteristic postmortem computed tomography findings of ingestion of benzine

There are some reports investigating the cause of death by examining the contents of the stomach and duodenum using postmortem computed tomography, but most of these have been based on radiopaque contents. Here, we report a case of suicide after ingesting a large amount of benzine. Although the gastric contents were radiolucent, the characteristic postmortem computed tomography imaging findings helped to determine the cause of death.

Navigating the perils and pitfalls of pediatric forensic postmortem imaging in the United States

Postmortem CT is widely used in the general adult and military populations. It is used extensively in pediatric death investigations in Europe and Asia, but distinctive challenges are encountered when launching a postmortem imaging program in the United States. We describe the issues we have encountered specific to establishing a pediatric postmortem imaging service in this country and propose potential solutions.

Longitudinal comparison of ascites attenuation between antemortem and postmortem computed tomography

OBJECTIVE

To investigate the changes in ascites attenuation between antemortem (AMCT) and postmortem computed tomography (PMCT) analyses of the same subjects.

METHODS

Thirty-five subjects who underwent unenhanced or enhanced AMCT within 7 days before death, unenhanced PMCT, and autopsy were evaluated. In each subject, ascites attenuation was measured at similar sites on AMCT and PMCT. Attenuation changes were evaluated in 42 unenhanced AMCT/PMCT site pairs (23 subjects) and 20 enhanced AMCT/PMCT site pairs (12 subjects). Factors contributing to CT attenuation changes were also assessed, including the time interval between AMCT and PMCT, serum albumin level, estimated glomerular filtration rate, and ascites volume.

RESULTS

Significantly elevated CT attenuation was observed between enhanced AMCT and PMCT (12.2 ± 6.3 vs. 18.7 ± 10.4 Hounsfield units; paired t-test, p = 0.006), but not between unenhanced AMCT and PMCT (13.5 ± 8.9 vs. 13.4 ± 9.3; p = 0.554). A significant inverse association was observed between the degree of CT attenuation change and the time interval between enhanced AMCT and PMCT (Spearman's rank correlation coefficient, r = -0.56, p = 0.01).

CONCLUSIONS

We confirmed an elevated level of ascites attenuation on PMCT relative to AMCT in subjects who underwent enhanced AMCT shortly before death.

Head and Brain Postmortem Computed Tomography-Autopsy Correlation in Hospital Deaths

The use of postmortem computed tomography (PMCT) to support autopsy pathology has increased in recent decades. To some extent, PMCT has also been contemplated as a potential alternative to conventional postmortem examination. The purpose of this study was to investigate the ability of PMCT to detect specific pathologic findings in the head and brain in natural hospital deaths.We examined postmortem CT images and autopsy data from 31 subjects who died at SUNY (State University of New York) Upstate University Hospital between 2013 and 2018. Each subject underwent a noncontrast PMCT and a traditional autopsy. A neuroradiologist analyzed PMCT images for head and brain abnormalities. The autopsies were performed by pathologists who were aware of the radiology results.In our series, PMCT was able to detect the majority of the significant space-occupying lesions, although it was not always reliable in ascertaining their nature. Postmortem computed tomography revealed findings usually challenging to detect at autopsy. Unfortunately, there were also situations in which PMCT was misleading, showing changes that were difficult to interpret, or that could be related to postmortem events. Therefore, we conclude PMCT should be used as an adjunct rather than a substitute to autopsy.

Pulmonary postmortem computed tomography of bacterial pneumonia and pulmonary edema in patients following non-traumatic in-hospital death

In this study, we compared the postmortem computed tomography (PMCT) findings among nonpathological lungs, lungs with bacterial pneumonia, and lungs with pulmonary edema in patients following non-traumatic in-hospital death. We studied 104 consecutive adult patients (208 lungs) who died in our tertiary care hospital and underwent PMCT and pathological autopsy (both within 2.5 days after death), and were pathologically diagnosed with nonpathological lungs, bacterial pneumonia, and pulmonary edema. Thirteen pulmonary features were assessed on the CT scans. We also examined the association between the time elapsed since death and the pulmonary findings. We observed increased lung opacities with horizontal plane formation, diffuse opacities, diffuse bronchovascular bundle thickening, symmetric opacities to the contralateral lung, and decreased segmental opacities with time elapsed since death (Cochran-Armitage test for trend). Multiple logistic regression revealed that the presence of opacities without horizontal plane formation or centrilobular opacities, and the absence of diffuse bronchovascular bundle thickening were associated with histopathological pneumonia, whereas the presence of opacities with horizontal plane formation, diffuse opacities, and interlobular septal thickening were associated with histopathological pulmonary edema. In conclusion, specific pulmonary PMCT findings increased with time elapsed since death, and some lung findings may facilitate the diagnosis of bacterial pneumonia and pulmonary edema.

Significance of intracranial gas on post-mortem computed tomography in traumatic cases in the context of medico-legal opinions

The detection of intracranial gas (ICG) in people who died due to trauma became possible once postmortem computed tomography (PMCT) became available in addition to traditional post-mortem examinations. The aim of this study was to determine the importance of ICG in the context of medico-legal opinions. We assessed 159 cases of trauma-induced death. Cadavers with pronounced signs of decomposition, open skull fractures, and after neurosurgical operations were excluded. Both PMCT findings and data from autopsy reports were analyzed. ICG was found in 38.99% (n = 62) of the cadavers, 96.77% (n = 60) of which presented with pneumocephalus (PNC) and 40.23% (n = 25) with intravascular gas (IVG). There was a strong correlation between ICG and skull fractures/brain injuries, as well as chest injuries, especially lung injuries. In 13 cases, ICG presented without skull fractures; three of these cases died as a result of stab and incised wounds to the neck and chest. The mean time between trauma and death was significantly longer in the non-ICG group than the ICG group at 2.94 days (0–48 days) and 0.01 day (0–1 day), respectively (p < 0.0001). The presence of ICG is a result of severe neck and chest injuries, including stab and incised wounds. The victims die in a very short amount of time after suffering trauma resulting in ICG. The ability to demonstrate ICG on PMCT scans can be of significance in forming medico-legal opinions.

Postmortem CT scan in intoxication cases: A necessity or just an indulgence

Introduction:

The aim of this study is to correlate urinary bladder distension and pulmonary edema on postmortem computed tomography (CT) scans with toxicology results in postmortem cases.

Methods and Results:

The study population was the postmortem cases of Asian population ranging from 16 to 75 years old in which blood and/or urine samples sent for alcohol and/or drug of abuse (DoA) analysis in year 2016 at our centre. Out of 434 cases, 54 from each group of positive and negative alcohol and/or DoA. Postmortem findings of lungs and postmortem CT scan urinary bladder volume (UBV) were recorded. Statistical significant correlation was obtained between urinary bladder distension on postmortem CT scan and cases with positive alcohol detection. However, the sensitivity was relatively low at 51.7%, whereas the specificity was 75% at the cut-off point. Low sensitivity and specificity at around 52.7% were obtained for pulmonary edema related to alcohol/DoA. This showed that UBV alone or pulmonary edema alone was not really a good indicator for alcohol or DoA intoxication. However, combination of both indicators provided higher sensitivity (73.3%) although specificity was lowered to 53.8%.

Conclusion:

The findings of postmortem CT scan bladder distension and pulmonary edema could possibly identify intoxication cases but not conclusive.

Pediatric postmortem computed tomography: initial experience at a children's hospital in the United States

Postmortem CT might provide valuable information in determining the cause of death and understanding disease processes, particularly when combined with traditional autopsy. Pediatric applications of postmortem imaging represent a new and rapidly growing field. We describe our experience in establishing a pediatric postmortem CT program and present a discussion of the distinct challenges in developing this type of program in the United States of America, where forensic practice varies from other countries. We give a brief overview of recent literature along with the common imaging findings on postmortem CT that can simulate antemortem pathology.

Post-mortem computed tomography (PMCT) radiological findings and assessment in advanced decomposed bodies

PURPOSE

The aim of the study is to report radiological findings and features in advanced decomposed bodies obtained by post-mortem computed tomography (PMCT) with autopsy correlation.

MATERIALS AND METHODS

This retrospective descriptive multicentric study included 41 forensic cases examined between May 2013 and November 2016. All the bodies were PMCT-scanned prior to autopsy, and internal putrefactive state was determined using the radiological alteration index (RAI) by a radiologist with expertise in forensic radiology and a forensic pathologist trained in forensic imaging. After PMCT scans, grade of external putrefaction (GEP) was assigned during the external examination and the complete autopsy was performed by forensic pathologists.

RESULTS

The PMCT images evaluation revealed that the RAI index was > 61 in all bodies, corresponding to a moderate-massive presence of putrefactive gas. The gas grade was > II in correspondence of the major vessels, heart cavities, liver parenchyma, vertebra L3 and subcutaneous pectoral tissues, and varied from I to III in correspondence of the kidney. Cadaveric external examination revealed the presence of advanced transformative phenomena, with a GEP3 and GEP4 in most of the cases, with body swelling, eyes and tongue protrusion, body fluids expulsion and fat liquefaction.

CONCLUSION

Radiological imaging by PMCT as an adjunct to autopsy in advanced decomposed bodies represents a useful tool in detecting post-mortem gas, even in very small amounts. A correct interpretation process of the PMCT data is essential to avoid images pitfalls, due to natural decomposition that can be mistaken for pathologic processes.

Postmortem volume change of the spleen and kidney on early postmortem computed tomography: comparison with antemortem computed tomography

PURPOSE

To clarify an early postmortem change, we investigated the volume changes of the spleen and kidney on postmortem CT compared with antemortem CT in the same patients.

MATERIALS AND METHODS

We retrospectively evaluated the volumes of 56 spleens (56 cases) and 50 kidneys (25 cases) using antemortem and postmortem CT, which were performed within 168 min after death. We divided the cases of spleen analysis into a hemorrhagic group (n = 12) and a non-hemorrhagic group (n = 44).

RESULTS

The volumes of the organs before and after death were 101.0 ± 70.9 (cm³, mean ± standard deviation) and 81.1 ± 57.8 in spleens, 120.3 ± 49.2 and 109.2 ± 39.2 in kidneys, respectively. Both spleens and kidneys shrank after death (p < 0.05). The volumes of spleens before and after death were 111 ± 66.5 and 67.5 ± 27.7 in the hemorrhagic group, and 98.2 ± 72.5 and 84.9 ± 63.3 in the non-hemorrhagic group, respectively. The median value of the ratio of postmortem splenic volume to antemortem volume in the hemorrhagic group (65.0%) was smaller than the one in the non-hemorrhagic group (90.5%) (p < 0.05).

CONCLUSION

We demonstrated that spleens and kidneys significantly reduced in size after death. The rate of shrinkage of spleens in the hemorrhagic group significantly became larger than the one in the non-hemorrhagic group.

Hematocrit Measurement with R2* and Quantitative Susceptibility Mapping in Postmortem Brain

BACKGROUND AND PURPOSE

Noninvasive venous oxygenation quantification with MR imaging will improve the neurophysiologic investigation and the understanding of the pathophysiology in neurologic diseases. Available MR imaging methods are limited by sensitivity to flow and often require assumptions of the hematocrit level. In situ postmortem imaging enables evaluation of methods in a fully deoxygenated environment without flow artifacts, allowing direct calculation of hematocrit. This study compares 2 venous oxygenation quantification methods in in situ postmortem subjects.

MATERIALS AND METHODS

Transverse relaxation (R2*) mapping and quantitative susceptibility mapping were performed on a whole-body 4.7T MR imaging system. Intravenous measurements in major draining intracranial veins were compared between the 2 methods in 3 postmortem subjects. The quantitative susceptibility mapping technique was also applied in 10 healthy control subjects and compared with reference venous oxygenation values.

RESULTS

In 2 early postmortem subjects, R2* mapping and quantitative susceptibility mapping measurements within intracranial veins had a significant and strong correlation (R² = 0.805, P = .004 and R² = 0.836, P = .02). Higher R2* and susceptibility values were consistently demonstrated within gravitationally dependent venous segments during the early postmortem period. Hematocrit ranged from 0.102 to 0.580 in postmortem subjects, with R2* and susceptibility as large as 291 seconds^-1 and 1.75 ppm, respectively.

CONCLUSIONS

Measurements of R2* and quantitative susceptibility mapping within large intracranial draining veins have a high correlation in early postmortem subjects. This study supports the use of quantitative susceptibility mapping for evaluation of in vivo venous oxygenation and postmortem hematocrit concentrations.

Burned bodies: post-mortem computed tomography, an essential tool for modern forensic medicine

Abstract

Currently, post-mortem computed tomography (PMCT) has become an accessible and contemporary tool for forensic investigations. In the case of burn victims, it provides specific semiologies requiring a prudent understanding to differentiate between the normal post-mortem changes from heat-related changes. The aim of this pictorial essay is to provide to the radiologist the keys to establish complete and focused reports in cases of PMCT of burn victims. Thus, the radiologist must discern all the contextual divergences with the forensic history, and must be able to report all the relevant elements to answer to the forensic pathologist the following questions: Are there tomographic features that could help to identify the victim? Is there evidence of remains of biological fluids in liquid form available for toxicological analysis and DNA sampling? Is there another obvious cause of death than heat-related lesions, especially metallic foreign bodies of ballistic origin? Finally, what are the characteristic burn-related injuries seen on the corpse that should be sought during the autopsy?

Teaching points

• CT is highly useful to find features permitting the identification of a severely burned body.

• PMCT is a major asset in gunshot injuries to depict ballistic foreign bodies in the burned cadavers.

• CT is able to recognise accessible blood for tests versus heat clot (air-crescent sign).

• Heat-related fractures are easily differentiated from traumatic fractures.

• Epidural collections with a subdural appearance are typical heat-related head lesions.

Comparison of the cardiothoracic ratio between postmortem and antemortem computed tomography

As postmortem imaging has gained prominence as a supplement to traditional autopsy, it is important to understand the normal postmortem changes to enable the accurate evaluation of postmortem imaging. No studies have evaluated the postmortem changes in cardiothoracic ratio (CTR) compared with antemortem images in the same subjects. We studied 147 consecutive subjects who underwent antemortem and postmortem CT, and autopsy. Postmortem CT was performed <23h after death and was followed by autopsy. The subjects were divided into three groups: normal heart, old myocardial infarction, and CPR-treated hearts. CTR was compared between antemortem and postmortem CT using paired t tests, which revealed that the CTR was greater on postmortem CT than on antemortem CT in all groups (mean CTR: 0.53±0.06vs. 0.50±0.06, respectively; P<0.01). Sex, age, time elapsed since death, and the causes of death were examined as potential confounding factors for the postmortem changes in CTR, but no significant associations were found. Receiver-operating characteristic (ROC) curves were used to determine CTR values for cardiomegaly, which was defined according to the autopsy weight of the heart. The area under the ROC curve was 0.71 (95% confidence interval 0.63-0.79). The CTR threshold of 0.54 identified cardiomegaly with the greatest accuracy, compared with the general threshold of 0.50. In conclusion, the CT-determined CTR increases after death, irrespective of the heart's condition. We should be cautious of overdiagnosis of cardiomegaly on postmortem CT, and new criteria for interpreting cardiomegaly on postmortem CTR are needed.

Can postmortem computed tomography detect antemortem hypoxic-ischemic encephalopathy?

The purpose of this study was to evaluate the usefulness of brain postmortem computed tomography (PMCT) findings for the detection of global hypoxia or hypoperfusion leading to hypoxic-ischemic encephalopathy (HIE) prior to death. Cadavers of individuals who died from non-traumatic causes were subjected to PMCT and pathological autopsy. Cases with an episode of cardiopulmonary arrest, hypoxia, or hypoperfusion that required intensive respiratory management at least 24 h before death and exhibited findings of HIE in conventional autopsy (HIE group, n = 6) were compared with those without such episodes prior to death (control group; overall, n = 37; age-matched, n = 8) with regard to four parameters: (1) width of the central sulcus (CS), (2) attenuation difference at the basal ganglia (BG) level, (3) attenuation difference between cerebral gray matter (GM) and cerebral white matter (WM), and (4) attenuation difference between cerebellar GM and cerebral GM. The results revealed significant differences in the width of the CS (P < 0.001), attenuation difference at the BG level (P < 0.001), and attenuation difference between cerebral GM and cerebral WM (P = 0.009) between the HIE group and the overall control group. When the age-matched control group and the HIE group were compared, there was a significant difference in the width of the CS (P = 0.026) and attenuation difference at the BG level (P < 0.001). Our results suggest that effacement of the sulcus of the cerebral hemisphere and the loss of contrast at the BG level on brain PMCT indicate the existence of HIE prior to death.

Evaluation of post-mortem lateral cerebral ventricle changes using sequential scans during post-mortem computed tomography

In the present study, we evaluated post-mortem lateral cerebral ventricle (LCV) changes using computed tomography (CT). Subsequent periodical CT scans termed “sequential scans” were obtained for three cadavers. The first scan was performed immediately after the body was transferred from the emergency room to the institute of legal medicine. Sequential scans were obtained and evaluated for 24 h at maximum. The time of death had been determined in the emergency room. The sequential scans enabled us to observe periodical post-mortem changes in CT images. The series of continuous LCV images obtained up to 24 h (two cases)/16 h (1 case) after death was evaluated. The average Hounsfield units (HU) within the LCVs progressively increased, and LCV volume progressively decreased over time. The HU in the cerebrospinal fluid (CSF) increased at an individual rate proportional to the post-mortem interval (PMI). Thus, an early longitudinal radiodensity change in the CSF could be potential indicator of post-mortem interval (PMI). Sequential imaging scans reveal post-mortem changes in the CSF space which may reflect post-mortem brain alterations. Further studies are needed to evaluate the proposed CSF change markers in correlation with other validated PMI indicators.

Postmortem Changes as Documented in Postmortem Computed Tomography Scans

The benefits and uses of postmortem computed tomography (PMCT) have been well documented in the forensic pathology and radiology literature in recent years and research into its utility continue in earnest. Opinions and policies regarding who actually interprets the PMCT scans vary between institutions, but in general, scans will be read by a forensic pathologist, a clinical radiologist, or a clinical radiologist with a special interest or training in postmortem imaging. Differences between clinical computed tomography scans and PMCT scans have been well documented and knowledge of these differences, typically those due to postmortem changes, is essential to the reader of the PMCT scan so as to minimize the risk of misinterpretation and, potentially, misdiagnoses.

Comparison of volume and attenuation of the spleen between postmortem and antemortem computed tomography

OBJECTIVES

The purpose of this study is to compare the postmortem changes in computed tomography (CT) findings between normal spleen, splenic infarct, and splenic tumor infiltration.

METHODS

The institutional review board approved this study, and informed consent was obtained from the next of kin. We studied 63 consecutive subjects who underwent antemortem CT, postmortem CT, and autopsy between February 2012 and December 2013. Postmortem CT was performed within 1678 min after death and was followed by pathological studies. The subjects were divided into three groups based on the pathological findings: normal, splenic infarct, and splenic tumor infiltration. The volume and attenuation of the spleen were compared between antemortem and postmortem CT using paired t tests. Gender, age, time elapsed since death, and the causes of death were examined as potential confounding factors of the postmortem changes in volume and attenuation.

RESULTS

In all groups, the spleen decreased in volume and attenuation increased on postmortem CT compared with antemortem CT. The postmortem changes in spleen volume and attenuation were not significantly associated with sex, age, time elapsed since death, or causes of death.

CONCLUSIONS

Spleen volume decreased and attenuation increased on postmortem CT compared with antemortem CT in subjects with a normal spleen, splenic infarct, or splenic tumor infiltration. These results should caution us against underestimating the significance of splenomegaly on postmortem CT, misinterpreting reduced splenic volume as the presence of hypovolemic or distributive shock in the subject while alive, and confusing postmortem splenic hyperattenuation with diseases characterized by this finding.