Whole body postmortem angiography with a high viscosity contrast agent solution using poly ethylene glycol as contrast agent dissolver

Postmortem minimal invasive angiography has already been implemented to support virtual autopsy examinations. An experimental approach in a porcine model to overcome an initially described artificial tissue edema artifact by using a poly ethylene glycol (PEG) containing contrast agent solution showed promising results. The present publication describes the first application of PEG in a whole corpse angiographic CT examination. A minimal invasive postmortem CT angiography was performed in a human corpse utilizing the high viscosity contrast agent solution containing 65% of PEG. Injection was carried out via the femoral artery into the aortic root in simulated cardiac output conditions. Subsequent CT scanning delivered the 3D volume data of the whole corpse. Visualization of the human arterial anatomy was excellent and the contrast agent distribution was generally limited to the arterial system as intended. As exceptions an enhancement of the brain, the left ventricular myocardium and the renal cortex became obvious. This most likely represented the stage of centralization of the blood circulation at the time of death with dilatation of the precapillary arterioles within these tissues. Especially for the brain this resulted in a distinctively improved visualization of the intracerebral structures by CT. However, the general tissue edema artifact of postmortem minimal invasive angiography examinations could be distinctively reduced.     

Postmortem Computed Tomography and Magnetic Resonance Imaging of Gunshot Wounds to the Neck

Postmortem magnetic resonance imaging (MRI) is rarely used for the radiologic assessment of gunshot injuries, although it has clear advantages over postmortem computed tomography (CT) with regard to the imaging of soft tissue injuries. Another benefit in using MRI is that lodged projectiles composed of nonferromagnetic material such as lead present only marginal metal artifacts compared with severe artifacts on CT. This case report presents CT and MRI findings in a case with two gunshot wounds to the neck: a perforating wound and a nonperforating wound with a lead bullet lodged in the cervical spine. The decedent underwent CT and MRI before the scheduled autopsy. A ring of radiopaque material under the dermis in the fatty tissue was identified at both entrance wounds on CT, which was indicative of contact shots. The perforating gunshot was clearly indicated on CT by bullet fragments along the wound channel through the perforated 6th cervical vertebra and the fractured cricoid cartilage at the exit wound. The second trajectory, however, was only assumed based on the presence of gunshot residues at the entrance wound and the position of the lodged bullet. The radiologic assessment was severely impeded by the metal artifacts on CT. Barely noticeable metal artifacts on MRI allowed for clear visualization of the soft tissue injuries and the ruptured medulla oblongata. Only MRI clarified the soft tissue injuries of the brainstem noninvasively, which could provide specific and graphic information on the rapidity of death and the incapacitation of the victim.     

Whole body postmortem magnetic resonance angiography

Computed tomography (CT) and magnetic resonance (MR) imaging have become important elements of forensic radiology. Whereas the feasibility and potential of CT angiography have long been explored, postmortem MR angiography (PMMRA) has so far been neglected. We tested the feasibility of PMMRA on four adult human cadavers. Technical quality of PMMRA was assessed relative to postmortem CT angiography (PMCTA), separately for each body region. Intra-aortic contrast volumes were calculated on PMCTA and PMMRA with segmentation software. The results showed that technical quality of PMMRA images was equal to PMCTA in 4/4 cases for the head, the heart, and the chest, and in 3/4 cases for the abdomen, and the pelvis. There was a mean decrease in intra-aortic contrast volume from PMCTA to PMMRA of 46%. PMMRA is technically feasible and allows combining the soft tissue detail provided by MR and the information afforded by angiography.     

CT‐Guided,Minimally Invasive,Postmortem Needle Biopsy Using the B‐Rob II Needle‐Positioning Robot

CT‐guided, minimally invasive needle biopsy techniques can be used to retrieve tissue or body fluid samples for histologic tissue diagnoses in forensic investigations. The purpose of this study was an evaluation of CT‐guided needle‐positioning robot B‐Rob II. To operate under CT guidance, we adopted the B‐Rob II robotic needle placement system and its workflow. The accuracy and speed of the procedure were tested on a gelatin phantom in a series of 21 biopsies. We achieved an average needle placement accuracy of 1.8 mm (±1.1 mm) using robotic assistance. The procedure required an average of 2 min 21 s. The needle placement accuracy for minimally invasive needle biopsies using the B‐Rob II biopsy robot is sufficiently accurate and fast for forensic postmortem examinations of focal organ changes. Further tests will be performed to test the feasibility of the robot for performing biopsies of focal organ changes in human bodies.     

Pneumomediastinum and Soft Tissue Emphysema in Pediatric Hanging

Postmortem computed tomography (CT) is increasingly being used as a tool in forensic pathology. The exact value of postmortem imaging in detecting specific conditions has not yet been established, but in specific cases, it can be used as a diagnostic tool demonstrating findings that remain undetected during autopsy, as in this case. Pneumomediastinum and soft tissue emphysema were detected with postmortem CT in a 3‐year‐old girl after hanging. It was not found during autopsy. This radiological finding matches 3 adult cases previously described. It is assumed that in this case, the first reported in a child, hanging was the most likely cause as well. In the adult cases, it was interpreted as a vital sign; the person must have been alive to create a pressure gradient causing rupture of the alveoli. This case demonstrates one of the added values of postmortem imaging, the possibility of demonstrating findings that remain undetected during autopsy.     

PEG-碘海醇对比剂的家兔死后血管显影初探

目的 为尸体血管造影剂组织外渗的评估建立一种动物模型.方法 配置不同浓度的碘海醇造影剂在体外进行CT扫描,选取ROI(S=100.0 mm2)并记录CT值;在家兔体内分别注射不同浓度的碘海醇造影剂后进行CT扫描,在主动脉弓内随机选取3个ROI(S=2.0 mm2)并记录CT值;在家兔体内分别注射不同浓度PEG+5％碘海...     

Quantitative MRI in Isotropic Spatial Resolution for Forensic Soft Tissue Documentation. Why and How?*

Abstract: A quantification of T1, T2, and PD in high isotropic resolution was performed on corpses. Isotropic and quantified postmortem magnetic resonance (IQpmMR) enables sophisticated 3D postprocessing, such as reformatting and volume rendering. The body tissues can be characterized by the combination of these three values. The values of T1, T2, and PD were given as coordinates in a T1–T2–PD space where similar tissue voxels formed clusters. Implementing in a volume rendering software enabled color encoding of specific tissues and pathologies in 3D models of the corpse similar to computed tomography, but with distinctively more powerful soft tissue discrimination. From IQpmMR data, any image plane at any contrast weighting may be calculated or 3D color‐encoded volume rendering may be carried out. The introduced approach will enable future computer‐aided diagnosis that, e.g., checks corpses for a hemorrhage distribution based on the knowledge of its T1–T2–PD vector behavior in a high spatial resolution.     

Carbon Monoxide Poisoning and Death in a Large Enclosed Ventilated Area

A 55‐year‐old man with a medical history of tobacco use suddenly collapsed while power washing an empty indoor pool in a hotel. The decedent was transported to the local hospital where he was pronounced. A postmortem examination revealed atherosclerotic heart disease and bilateral pulmonary edema and congestion. A postmortem blood carbon monoxide (CO) level was 27% saturation, and a CO performed on hospital admission blood was 49% saturation. CO poisoning is a common cause of toxicological morbidity and mortality in the United States. The circumstances most often occur in an enclosed environment and may be intentional or unintentional. CO poisoning has been reported in open, well‐ventilated spaces, but rarely results in death. A warning label was present on the engine clearly stating the dangers of CO emission. However, there was a false sense of security due to the large size of the pool room and the presence of industrial blowers that were being used for ventilation.     

Differentiation of Antemortem and Postmortem Appendicular Fractures Using Magnetic Resonance Imaging Signal Intensity Changes in Bone and Soft Tissues,

Intraosseous T1-weighted (T1W) and short-tau inversion recovery (STIR) magnetic resonance imaging (MRI) signal intensity changes—so-called bone marrow edema—may be able to differentiate antemortem and postmortem fractures in human forensic imaging. The primary objective of this study was to investigate this hypothesis using an animal model. Three juvenile Landrace pigs were anesthetized and underwent MRI of both tibiae and both radii using a 1.5 T magnet. T1W, T2-weighted (T2W), STIR, and T2* sequences were included. Antemortem fractures were induced in both tibiae and postmortem fractures in both radii, and MRI was repeated. Two board-certified radiologists blinded to fracture group jointly evaluated the images for intraosseous and soft tissue signal intensity changes. Sensitivity (Se) and specificity (Sp) in identifying antemortem fractures were calculated based on intraosseous, soft tissue, and combined intraosseous and soft tissue signal intensity changes. Intraosseous and soft tissue signal intensity changes, when present, were hyperintense in all sequences. Intraosseous hyperintensity in T1W and T2W sequences yielded Sp of 100% for antemortem fractures. Regardless of sequence, soft tissue hyperintensity was comparatively more sensitive than intraosseous hyperintensity. Sensitivity for each sequence could be maximized by assessment of soft tissue and intraosseous hyperintense signals together; for the T1W sequence, such assessment optimized diagnostic utility yielding a Se of 100% and Sp of 83%. In summary, MRI—particularly the T1W sequence—can differentiate antemortem and postmortem fractures and may be a useful adjunct to the forensic analyses of fractures.     

Olanzapine‐Induced Fatal Ketoacidosis with Pneumomediastinum and Subcutaneous Emphysema

We report a case of fatal olanzapine‐induced ketoacidosis in which pneumomediastinum (PM) and subcutaneous emphysema (SE) were detected on postmortem computed tomographic (CT) images. A man in his forties was found in a state of cardiopulmonary arrest with profuse perspiration, and 50 empty capsules of olanzapine (10 mg) and flunitrazepam (1 mg) were found in his room. The major findings of postmortem CT prior to autopsy were PM and SE from the lower half of the face to the height of the first rib. The results of autopsy, biochemical tests, and toxicological analyses indicated the cause of death to be fatal ketoacidosis induced by olanzapine intoxication. No injuries, medical interventions, or particular diseases were evident, suggesting that PM and SE were caused by ketoacidosis. Our findings indicated that toxicological analyses should be performed when PM and SE are detected on CT images.     

放射影像学在颈部损伤尸体检验中的应用

多层面计算机断层成像(MSCT)和磁共振成像(MRI)对尸体骨骼系统和软组织损伤的诊断价值等同于传统的尸体解剖,运用在颈部损伤的尸体检验中可以弥补传统尸体解剖的某些不足,在某些特定的环境、腐败、烧焦或具有传染性的尸体检验中,MSCT和MRI联合使用可以作为机械性窒息、挥鞭样损伤、颈椎损伤及颈部血管损伤的可选择的法医学检查手段之一。     

LIFE BEYOND LIFE – An Easy Way to Derive Lung Fibroblasts from Cadavers

Several protocols have illustrated the possibility of deriving cells, such as fibroblasts, from different organs. These techniques generally concern organs sampled from living persons, but have already been described for cadavers, especially concerning the skin and tendons. We present, for the first time, an easy way to derive pulmonary fibroblasts from a lung tissue sampled from a cadaver and directly culture plated. The fibroblast output was checked daily. We obtained lung fibroblasts from 3 (60%) cadavers and 2 (100%) living persons. The fibroblast output took about 3 days for cells from living persons and took up to 39 days for those from cadavers. We did not clearly identify any parameters that could explain these differences. Nevertheless, these derived cells had the same features as the source cells, especially in terms of morphology and proliferation, and could potentially be used in different research domains such as forensic or regeneration medicine.     

Postmortem Aortic Dissection: An Artifact of the Embalming Process

Aortic dissection (AD) is a serious condition that affects 3/100,000 individuals a year. Recently, a case report was published describing an embalmed patient with an aortic dissection. The purpose of this study was to examine the frequency of AD among 80 embalmed cadavers and confirm the AD with histopathologic evaluation. In seven cases of grossly identified AD, six were determined to be due to the embalming procedure and only one case of true antemortem AD was confirmed. These results suggest that aortic morphology can be altered by administration of the embalming fluid and that alterations can mimic AD, not only on gross inspection but also on postmortem imaging. Awareness of this embalming artifact may prevent misdiagnosis of an aortic dissection in an embalmed patient, a point particularly useful for autopsy pathology that may include postmortem examination of an embalmed patient.     

Evaluation of Computed Tomography as a Screening Test for Death Inquest

Abstract: The Japanese method of inquest, which depends mostly on external examinations, may misdiagnose a considerable number of accidental deaths and suicides as death by disease. We conducted computed tomography (CT) scans of 80 cases for which police concluded death by disease or natural causes based on police investigations into the circumstances and results from external examinations. The cause of death was clearly determined by CT scan in 17 of 80 cases. Ten cases underwent autopsy after the police suspected criminality based on results of the CT examinations. The results suggest CT scan may be a tool for preventing a number of overlooked crimes and accidents in Japan. However, it cannot be a perfect tool for discerning between death by disease and other causes of death without cooperation from the investigative agencies and subsequent forensic examinations such as autopsy and toxicological tests.     

Massive systemic fat embolism detected by postmortem imaging and biopsy*

Postmortem computed tomography (pmCT) and pmCT angiography (pmCTA) provide a minimally invasive method to determine the cause of death. Postmortem image-guided biopsy allows for precise sampling of histological specimens. This case study describes the findings of lethal systemic fat embolism (FE) on whole-body unenhanced pmCT, pmCTA, and image-guided biopsy, with autopsy and histopathologic correlation. Unenhanced pmCT revealed a distinct fat level on top of sedimented layers of corpuscular blood particles and serum in the arterial system and pulmonary trunk. Subsequent pmCTA showed reproducible results, and image-guided biopsy confirmed fatal FE. pm CT/pmCTA combined with image-guided biopsy established the cause of death as right heart failure as a result of systemic fatal FE prior to autopsy. All imaging findings were consistent with traditional autopsy and histological specimens. This unique case demonstrates new imaging findings in massive, fatal FE and highlights that postmortem imaging, supplemented by image-guided biopsy, may detect the cause of death prior to traditional autopsy.     

Dental CT imaging as a screening tool for dental profiling: advantages and limitations

The use of dental processing software for computed tomography (CT) data (Dentascan) is described on postmortem (pm) CT data for the purpose of pm identification. The software allows reconstructing reformatted images comparable to conventional panoramic dental radiographs by defining a curved reconstruction line along the teeth on oblique images. Three corpses that have been scanned within the virtopsy project were used to test the software for the purpose of dental identification. In every case, dental panoramic images could be reconstructed and compared to antemortem radiographs. The images showed the basic component of teeth (enamel, dentin, and pulp), the anatomic structure of the alveolar bone, missing or unerupted teeth as well as restorations of the teeth that could be used for identification. When streak artifacts due to metal-containing dental work reduced image quality, it was still necessary to perform pm conventional radiographs for comparison of the detailed shape of the restoration. Dental identification or a dental profiling seems to become possible in a noninvasive manner using the Dentascan software.     

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.     

Application of Postmortem 3D‐CT Facial Reconstruction for Personal Identification*

Abstract: Postmortem computed tomography (CT) images can show internal findings related to the cause of death, and it can be a useful method for forensic diagnosis. In this study, we scanned a ready‐made box by helical CT on 2‐mm slices in a mobile CT scanner and measured each side of the box to assess whether reconstructed images are useful for superimposition. The mean difference between the actual measurements and the measurements on the three‐dimensional (3D) reconstructed images (3D‐CT images) is 0.9 mm; we regarded it as having no effect on reconstruction for the superimposition method. Furthermore, we could get 3D‐CT images of the skull, which were consistent with the actual skull, indicating that CT images can be applied to superimposition for identification. This study suggested that postmortem CT images can be applied as superimpositions for unidentified cases, and thinner slices or cone beam CT can be a more precise tool.     

脑组织与法医学死亡时间推断

目前，通过脑组织推断死亡时间已经成为法医学领域研究的新热点，大量研究资料表明：死亡时间与脑组织细胞DNA、RNA、ATP含量及脑温度、脑组织血管内皮生长因子等变化有高度相关性。脑CT、MRI、磁共振波谱等检查手段对死亡时间的推断也有帮助。本文对国内外相关文献进行综述，以期为相关研究提供参考。