Perimortem Skeletal Sharp Force Trauma: Detection Reliability on CT Data, Demographics and Anatomical Patterns from a Forensic Dataset.

The increasing importance of trauma analysis by means of postmortem computed tomography (PMCT) is insufficiently reflected in forensic curricula, nor are best practice manuals available. We attempt to detect sharp force bone lesions on PMCT of closed forensic cases with the aims of assessing errors and pointing out patterns in anatomical location and manner of death (MOD). We investigated 41 closed sharp force fatality cases, with available PMCT and forensic reports. Two observers with different radiological training assessed the lesions on PMCT scans (2D and 3D) for comparison with the reports. Between 3% (suicides) and 15.3% (homicides) of sharp force injuries caused visible bone lesions. While our observations were repeatable, each forensic investigation left a similar number of bone lesions undetected. Injury patterns differed between MOD, with thoracic bone lesions being most frequent overall. Soft tissue injury location varied between the MOD. Associations between MOD and age as well as number of injuries were significant. The detection of bone lesions on PMCT for untrained forensic specialists is challenging, curricula and pertinent manuals are desirable. With the low frequency of bone lesions compared to soft tissue injuries, we should be aware when analyzing decomposed bodies.

Postmortem computed tomography differentiation between intraperitoneal decomposition gas and pneumoperitoneum.

PURPOSE: The aim of this study is to investigate the ability of postmortem computed tomography (PMCT) to distinguish intraperitoneal decomposition gas from pneumoperitoneum due to intestinal perforation. METHODS: This retrospective study investigated the factors affecting intraperitoneal gas in two groups of 14 decedents as detected by postmortem CT performed in the Department of Legal Medicine of Hamburg University. The first group died with a cause of death associated with intestinal perforation, and the second group with other different natural causes of death. These factors include postmortem interval, gas volume, gas distribution, radiology alteration index (RAI), and pneumoperitoneum-associated pathology. RESULTS: The findings of this study showed the appearance of specific gas distribution patterns and a significant increase in gas volumes in the cases of intestinal perforation. Moreover, postmortem interval and the pneumoperitoneum-associated pathology could help distinguish postmortem-generated gas from pneumoperitoneum. CONCLUSION: Based on the findings of this study, we propose that these findings can improve the proper detection of intestinal perforation cases in the future.

Diagnostic accuracy of postmortem computed tomography for bleeding source determination in cases with hemoperitoneum.

AIM: The aim of this retrospective study was to determine the accuracy of postmortem computed tomography and different radiological signs for the determination of the bleeding source in cases with hemoperitoneum confirmed at autopsy. METHODS: Postmortem computed tomography data of consecutive cases with hemoperitoneum confirmed at autopsy were reviewed by two raters, blinded to the autopsy findings. The determination of possible bleeding sources was based on the presence of the sentinel clot sign, blood or sedimented blood surrounding an organ, intraparenchymal abnormal gas distribution, and parenchymal disruption. The bleeding source and the cause of hemoperitoneum (traumatic, surgical, natural, or resuscitation) as reported in the autopsy report were noted. The survival intervals of the deceased were calculated when information about the time of an incident related to death was available in the autopsy reports. RESULTS: Eighty-five cases were included in the study. Postmortem computed tomography showed 79% sensitivity and 92.1% specificity for the detection of the bleeding source. The sentinel clot sign was associated with surgical or natural causes of hemoperitoneum and longer survival intervals. Sedimented blood around the bleeding source was associated with resuscitation. Abnormal gas distribution within organs and combination of multiple radiological signs provided higher sensitivity. CONCLUSION: Postmortem computed tomography provides moderate sensitivity and high specificity for determining the bleeding source in cases with hemoperitoneum. Different PMCT signs are associated with different causes of hemoperitoneum and survival intervals.

Postmortem Computed Tomography in Firearm Homicides: A Retrospective Case Series.

Postmortem computed tomography (PMCT) is integrated into the evaluation of decedents in several American medical examiner offices and medicolegal death investigative centers in many other countries. We retrospectively investigated the value of PMCT in a series of firearm homicide cases from a statewide centralized medical examiner's office that occurred during 2016. Autopsies were performed or supervised by board-certified forensic pathologists who reviewed the PMCT scans prior to autopsy. PMCT scans were re-evaluated by a forensic radiologist blinded to the autopsy findings and scored by body region (head-neck, thoracoabdominal, and extremities). Injury discrepancies were scored using a modified Goldman classification and analyzed with McNemar's test. We included 60 males and 20 females (median age 31 years, range 3-73). Based on PMCT, 56 (79.1%) cases had injuries relevant to the cause of death in a single body region (24 head-neck region, 32 thoracoabdominal region). Out of these 56 cases, 9 had a missed major diagnosis by PMCT outside that region, including 6 extremity injuries visible during standard external examination. Yet all had evident lethal firearm injury. We showed that PMCT identifies major firearm injuries in homicide victims and excludes injuries related to the cause of death in other regions when a single body region is injured. Although PMCT has a known limited sensitivity for soft tissue and vascular pathology, it can be combined with external examination to potentially reduce or focus dissections in some of these cases depending on the circumstances and medicolegal needs.

Evaluation of an acetated Ringer-based contrast material mixture for postmortem computed tomography angiography.

PURPOSE: The purpose of this study was to compare an established postmortem contrast medium mixture based on polyethylene glycol (PEG) to an isotonic crystalloid with acetated Ringer solution (AR) as the base, both mixed with water-soluble iodinated contrast medium for postmortem computed tomography angiography (PMCTA) with the aim to avoid alterations of the corpse during autopsy. MATERIALS AND METHODS: The study included 20 cadavers; 10 had PMCTA with AR and 10 with PEG. PMCTA images were analyzed with respect to image quality, vascular contrast patterns and artifacts. Autopsy was evaluated for visual, organ, vessel and haptic alterations. The Wilcoxon rank sum test was used to search for differences in image quality between the two groups. Statistical significance was set at P<0.05. RESULTS: AR provided excellent contrast within the right coronary artery (P<0.001) but a lack of contrast within the left coronary artery (P=0.008) whereas PEG showed the opposite. A better image quality was observed in the PEG group by comparison with the AR group for right common carotid artery (P=0.03), left common carotid artery (P=0.01) and left coronary artery (P=0.008). No differences were found for ascending aorta (P=0.65), aortic arch (P=0.09), right circle of Willis (P=0.17), left circle of Willis (P=0.08), inferior vena cava (P=0.07) and abdominal aorta (P=0.08). Severe extravasation occurred in all (10/10; 100%) cadavers in the AR group but in none (0/10; 0%) in the PEG group (P<0.001). At autopsy, visual alteration with lilac discoloration of the face was observed in 4/10 cadavers (40%) in the AR group and in 9/10 cadavers (90%) in the PEG group (P=0.057). Haptic alterations were observed in 3/10 cadavers (30%) in the AR group and 10/10 cadavers (100%) in the PEG group (P=0.003). CONCLUSION: AR results in contrast medium mixture extravasation in all cadavers, but PEG altered the autopsy more severely. Both carrier substances result in specific substance-related artifacts and dependent opacification of the coronary arteries, but PEG is recommended for PMCTA exclusively with regard to diagnostic imaging.

Stature Estimation from Postmortem CT Femoral Maximum Length in Contemporary Danish Population.

Stature estimation methods for Danish adult population have generally relied on Trotter and Gleser's and Boldsen's regression equations that are based on the skeletal remains of recent war dead American Whites, Terry Skeletal Collection, and Danish archaeological medieval skeletal materials, respectively. These equations are probably not suitable for stature estimation in contemporary Danish forensic cases. Furthermore, because postmortem computed tomography (PMCT) is now routinely performed at Danish forensic departments, equations based on PMCT, rather than measurements of defleshed bones, are needed. The aim of this study was to develop new equations for adult stature estimation based on PMCT femoral measurement. Maximum femoral length was measured on the PMCT images of 78 individuals (41 males and 37 females) aged 23-45 years. The measurement accuracy was tested on dry bones, and all the measurements were included in the inter- and intra-observer analyses. Both analyses results demonstrated the reliability of the method and data. Comparison between the living stature of the individuals and the estimates based on the equations by Trotter and Gleser and Boldsen demonstrated the unreliability of the previous equations to some extent. New regression equations were then developed and validated on a different sample of 18 Danish forensic cases. Comparisons of all the equations indicated that both the sets of previous equations underestimated the stature in the new validation dataset. The new equations developed in this study provide a reliable alternative for stature estimation in modern Danish forensic cases.

Death by hanging: a retrospective case-control investigation of the intervertebral disc vacuum phenomenon on PMCT.

During hanging gravitational forces affect the spine. Intervertebral vacuum phenomenon (VP) implies that gas accumulations in the discs are caused by degeneration of the spine and trauma. It was hypothesized that VP detected on postmortem computed tomography (PMCT) has a higher incidence in hanging deaths, which can be correlated to age, degenerative spinal changes and type of hanging (complete-incomplete). Secondly, it was investigated whether the presence of Simon's bleedings is related to hanging type and VP on PMCT. A retrospective hanging case-control study of 72 cases was conducted. PMCT data were evaluated by two observers for the presence of VP and its localization within the thoracic and lumbar discs, and for any degenerative changes of the spine. Autopsy protocols were assessed for the presence of Simon's bleedings during autopsy. VP did not statistically differ among hanging and control cases but it was statistically correlated to complete hanging, increasing age and degenerative spinal changes. Centrally located VP within the discs was correlated to hanging, especially complete hanging, and younger ages, contrary to control cases that showed gas at the disc periphery. Simon's bleedings were correlated with complete hanging and centrally located VP. Centrally located VP within the discs increases the probability for complete hanging, while increasing age and degenerative changes reduce this probability. Intervertebral VP is multifactorial radiological entity. The presence of centrally located VP can indicate that hanging could be considered as an alternative mechanism of death and that great forces and loads may have affected the spine perimortem, especially with decreasing age and when Simon's bleedings are present.

[Postmortem imaging procedures : Experiences and perspectives]. / Postmortale bildgebende Verfahren : Erfahrungen und Ausblicke.

Autopsies are of key importance for the understanding of the anatomy, pathophysiology and pathomorphology. In forensic medicine, the virtual autopsy is a standard instrument in autopsy practice. The advantage of postmortem imaging is the generation of a three-dimensional pre-autopsy snapshot of the body from head to toe with excellent visualization of skeletal pathologies and air inclusions. When angiography is performed, pathologies of the cardiovascular system can additionally be evaluated. The shortcomings of postmortem imaging are the low soft tissue contrast with CT imaging, the lack of haptic, olfactory and color impressions. Another limitation is the access to CT and particularly to magnetic resonance imaging (MRI) facilities and the necessary experience with the peculiarities of postmortem imaging. To date, postmortem imaging can supplement but not replace the traditional autopsy. Nevertheless, postmortem imaging adds valuable technical capabilities to the traditional autopsy. The ability to achieve valid results for the cause of death and additional diagnoses must be evaluated systematically for postmortem imaging, in particular in addition to CT or MR guided biopsies. This article gives an overview of the current state of the technology and encourages its development for application in pathology departments.

Differentiation of hemopericardium due to ruptured myocardial infarction or aortic dissection on unenhanced postmortem computed tomography.

The aim of the study was to evaluate unenhanced postmortem computed tomography (PMCT) in cases of non-traumatic hemopericardium by establishing the sensitivity, specificity and accuracy of diagnostic criteria for the differentiation between aortic dissection and myocardial wall rupture due to infarction. Twenty six cases were identified as suitable for evaluation, of which ruptured aortic dissection could be identified as the underlying cause of hemopericardium in 50% of the cases, and myocardial wall rupture also in 50% of the cases. All cases underwent a PMCT and 24 of the cases also underwent one or more additional examinations: a subsequent autopsy, or a postmortem magnetic resonance (PMMR), or a PMCT angiography (PMCTA), or combinations of the above. Two radiologists evaluated the PMCT images and classified each case as "aortic dissection", "myocardial wall rupture" or "undetermined". Quantification of the pericardial blood was carried out using segmentation techniques. 17 of 26 cases were correctly identified, either as aortic dissections or myocardial ruptures, by both readers. 7 of 13 myocardial wall ruptures were identified by both readers, whereas both readers identified correctly 10 of 13 aortic dissection cases. Taking into account the responses of both readers, specificity was 100% for both causes of hemopericardium and sensitivity as well as accuracy was higher for aortic dissections than myocardial wall ruptures (72.7% and 87.5% vs 53.8% and 75% respectively). Pericardial blood volumes were constantly higher in the aortic dissection group, but a statistical significance of these differences could not be proven, since the small count of cases did not allow for statistical tests. This study showed that diagnostic criteria for the differentiation between ruptured aortic dissection and myocardial wall rupture due to infarction are highly specific and accurate.

Medico-Legal Aspects of Pulmonary Thromboembolism.

Pulmonary ThromboEmolism (PTE) is an important disease for legal medicine. Because of their sudden lethal onset, generally medicolegal autopsies show few clinical information when PTE is the cause of death. During medicolegal autopsies, the autopsy operator must answer to important questions. For example, autopsy operator can need to assess the casual relationship between PTE and recent accident, such as trauma or long air travel. Furthermore, the autopsy operator needs to investigate the pathology of PTE as a cause of sudden cardiovascular death. It is relatively simple to confirm a fatal massive thromboembolus in the initial stage of thoracic investigations, but sometimes it might be difficult to distinguish this from postmortem clot. In such cases histopathological examination can help in the differentiation. Histological examination is also required for observation of chronological changes of the thrombi. Chronological evaluation is an important factor especially to determine whether the death coincides with the date of a specific accident/event or instead there is an earlier onset of PTE. In addition, histological sections sometimes show additional information, such as tumor fragments in cases of malignancy or small fragments of bone marrow in cases of active resuscitation, that can be useful in a medicolegal scenario. Furthermore, new diagnostic tools are arising, which they can be very helpful in the individuation of this frequently underdiagnosed disease. The goal of our work is to investigate these aspects through the review of the recent literature.

Racking the brain: detection of cerebral edema on postmortem computed tomography compared with forensic autopsy.

PURPOSE: The purpose of this study was to compare postmortem computed tomography with forensic autopsy regarding their diagnostic reliability of differentiating between pre-existing cerebral edema and physiological postmortem brain swelling. MATERIALS AND METHODS: The study collective included a total of 109 cases (n=109/200, 83 male, 26 female, mean age: 53.2 years) and were retrospectively evaluated for the following parameters (as related to the distinct age groups and causes of death): tonsillar herniation, the width of the outer and inner cerebrospinal fluid spaces and the radiodensity measurements (in Hounsfield Units) of the gray and white matter. The results were compared with the findings of subsequent autopsies as the gold standard for diagnosing cerebral edema. p-Values <0.05 were considered statistically significant. RESULTS: Cerebellar edema (despite normal postmortem swelling) can be reliably assessed using postmortem computed tomography and is indicated by narrowed temporal horns and symmetrical herniation of the cerebellar tonsils (p<0.001). There was a significant difference (p<0.001) between intoxication (or asphyxia) and all other causes of death; the former causes demonstrated higher deviations of the attenuation between white and gray matter (>20 Hounsfield Units), and the gray to white matter ratio was >1.58 when leukoencephalopathy was excluded. CONCLUSIONS: Despite normal postmortem changes, generalized brain edema can be differentiated on postmortem computed tomography, and white and gray matter Hounsfield measurements help to determine the cause of death in cases of intoxication or asphyxia. Racking the brain about feasible applications for a precise and reliable brain diagnostic forensic radiology method has just begun.

Pericardial tear as a consequence of cardiopulmonary resuscitation (CPR) involving chest compression: a report of two postmortem cases of acute type A aortic dissection with hemopericardium.

We present two cases of a pericardial tear as a consequence of cardiopulmonary resuscitation involving chest compressions in fatal acute type A aortic dissection (AoD) with hemopericardium. For each case, postmortem computed tomography revealed a hematoma in the false lumen of the ascending aorta with a slight hemopericardium and a large left hemothorax, as well as focal pericardial dimpling and discontinuity around the left ventricle. At autopsy, we confirmed a convex lens-shape gaping pericardial tear at the left posterolateral site of the pericardium and a massive volume of bloody fluid in the left thoracic cavity. It has been hypothesized that the pericardium ruptured due to chest compressions during resuscitation in these cases of acute type A AoD with hemopericardium and that intrapericardial blood leakage through the pericardial tear resulted in a hemothorax.

Immediate non-traumatic postmortem computed tomographic demonstration of myocardial intravascular gas of the left ventricle: effects from cardiopulmonary resuscitation.

An 87-year-old man was found in a state of cardiopulmonary arrest. Despite cardiopulmonary resuscitation (CPR) for over 1 hour by emergency technicians and physicians, the patient died. Immediate postmortem computed tomography showed cardiovascular gas in the right atrium, right ventricle, and left ventricle. Cardiovascular gas in the left ventricle was located in the myocardium and appeared as linear or branch-shaped suggesting the presence of myocardial intravascular gas. This is the first report describing the appearance and significance of myocardial intravascular gas of the left ventricle as a CPR-related change.

Postmortem computed tomography is an informative approach for prevention of sudden unexpected natural death in the elderly.

INTRODUCTION: Less than 10% of unnatural death cases have been examined by autopsy in Japan. In particular, the causes of death in the elderly have not yet been actively investigated. Here, we evaluated the possible use of postmortem computed tomography (PMCT) to investigate the causes of sudden unexpected natural death (SUND) in the elderly. METHODS AND SUBJECTS: Death cases confirmed within 24 hours since the onset of symptoms at the Emergency Department of Mie University Hospital were defined as sudden death cases. A total of 212 sudden death cases, including 175 SUND cases, that occurred in a 3-year period from September 2006 to August 2009 were investigated. RESULTS AND DISCUSSION: The number of sudden death cases was highest in patients in their seventies (56 cases, 26%), followed by patients in their eighties and sixties. Sudden death occurred more in men than in women in their fifties to seventies, while it occurred more in women than in men over the age of 90. PMCT was performed in more than 80% of SUND cases regardless of age of the deceased. The causes in 26 cases (27.1%) were established by PMCT, many of which were hemorrhagic diseases. Signs of aortic aneurysm rupture were detected by PMCT in the thoracic and abdominal areas of 8 patients in their seventies and over, whereas signs were absent in the younger group. Also, more than 18% of sudden death cases in patients in their seventies and over were bathing-related sudden death (BRSD). BRSD was rarely caused by hemorrhagic diseases, suggesting that a drop in blood pressure caused by bathing is an important factor in BRSD. CONCLUSION: PMCT is a method that is relatively acceptable by bereaved families. It is useful for establishing the causes of approximately 30% of the SUND cases examined. The PMCT findings suggested that early detection and treatment of thoracic and abdominal aortic aneurysms and preventive measurements of bathing-related drop in blood pressure are important for the prevention of SUND in the elderly.