Visualization of bridging veins by means of postmortem computed tomography

At autopsy, visualization of lesions of the bridging veins, a frequent source of subdural bleeding, is difficult due to their anatomical localization. On the other hand their demonstration is of great importance for the assignment to a chronologically defined trauma. For this reason a postmortem method using computed tomography was developed to visualize the intracranial venous system by means of X-ray contrast media. In subdural bleedings, in which the skull had not been opened up, ruptured vessels could be accurately localized with this method, so that targeted dissection was possible during the subsequent autopsy.     

Blood aspiration as a vital sign detected by postmortem computed tomography imaging

Blood aspiration is a significant forensic finding. In this study, we examined the value of postmortem computed tomography (CT) imaging in evaluating findings of blood aspiration. We selected 37 cases with autopsy evidence of blood in the lungs and/or in the airways previously submitted to total-body CT scanning. The CT-images were retrospectively analyzed. In one case with pulmonary blood aspiration, biopsy specimens were obtained under CT guide for histological examination. In six cases, CT detected pulmonary abnormalities suggestive of blood aspiration, not mentioned in the autopsy reports. CT reconstructions provided additional data about the distribution and extent of aspiration. In one needle-biopsied case, the pulmonary specimens showed blood in the alveoli. We suggest the use of CT imaging as a tool complementary to traditional techniques in cases of blood aspiration to avoid misdiagnosis, to guide the investigation of lung tissue, and to allow for more evidence-based inferences on the cause of death.     

Disaster victim identification: new applications for postmortem computed tomography

Abstract:  Mass fatalities can present the forensic anthropologist and forensic pathologist with a different set of challenges to those presented by a single fatality. To date radiography has played an important role in the disaster victim identification (DVI) process. The aim of this paper is to highlight the benefits of applying computed tomography (CT) technology to the DVI process. The paper begins by reviewing the extent to which sophisticated imaging techniques, specifically CT, have been increasingly used to assist in the analysis of deceased individuals. A small scale case study is then presented which describes aspects of the DVI process following a recent Australian aviation disaster involving two individuals. Having grided the scene of the disaster, a total of 41 bags of heavily disrupted human remains were collected. A postmortem examination was subsequently undertaken. Analysis of the CT images of all body parts ( n  = 162) made it possible not only to identify and side differentially preserved skeletal elements which were anatomically unrecognizable in the heavily disrupted body masses, but also to observe and record useful identifying features such as surgical implants. In this case the role of the forensic anthropologist and CT technology were paramount in facilitating a quick identification, and subsequently, an effective and timely reconciliation, of body parts. Although this case study is small scale, it illustrates the enormous potential for CT imaging to complement the existing DVI process.     

新西兰白兔死亡后颅脑CT检查与死亡时间关系的研究

目的采用CT扫描动态观察新西兰白兔死亡后脑组织变化,建立利用CT值、脑组织/颅腔面积比,推断死亡时间(PM I)的研究方法。方法通过耳缘静脉注射空气,建立新西兰白兔死亡模型;于死亡后0~120h,运用CT进行头颅平描;选取颅顶面层测定脑组织CT值、脑组织/颅腔面积比。结果死亡后兔脑组织CT值呈双峰样上升、脑组织/颅腔面积比呈不断下降趋势;建立与死亡时间的回归方程:CT值=47.4780-0.1768T+0.0049T2(T/h,CT值/HU)、面积比=99.7368+0.3098T-0.0118T2/100(T/h)。结论CT扫描检查可准确显示兔脑的死后变化;脑组织消失之前,综合运用CT检查指标可用于准确推断死亡时间。     

死后尸体CT在法医学鉴定中的应用价值初探

目的 对不同类型案件中的死者进行死后尸体CT扫描和常规尸体解剖,探索PMCT在法医学鉴定中的应用价值.方法 对7例因不同原因死亡的个体进行全身PMCT扫描,随后进行系统的尸体解剖,通过比较两种方法检测的结果,分析PMCT与传统尸体解剖在不同类型案件中应用的优点和不足.结果 在7个案例中,尸体上总共检出67处阳性发现.其...     

Gas at postmortem computed tomography - An evaluation of 73 non-putrefied trauma and non-trauma cases

Postmortem computed tomography (PMCT) has become an important complement in investigating forensic cases allowing an accurate detection of gas accumulations. The present study investigated the presence and distribution of gas in a large number of non-putrefied cases of traumatic and non-traumatic deaths. Furthermore the possibility of pneumobilia secondary to blunt abdominal trauma was studied. Retrospectively, 73 cases, underwent a whole-body PMCT prior to autopsy. These were divided into four groups: penetrating trauma (20 gunshot cases, 13 stabbing cases), blunt abdominal trauma (20 cases) and a control group of 20 non-trauma cases. Exclusion criteria were visible signs of decomposition. Each group was screened for gas accumulations in the vascular system, internal organs, soft tissues and body cavities. Gas accumulations were present in 98% of the trauma cases, compared to 80% of the control group. The most affected structures and/or organs in the trauma group were soft tissues, vessels and the liver. In most cases of the trauma group gas was associated with open injuries and lacerations of vessels. Furthermore, in the gunshot group gas was frequently seen in the intracranial cavity. Pneumobilia occurred in one case of the blunt trauma group; in that control group gas was also seen, but less frequently. Gas accumulation showed a strong association with traumatic events, but even the majority of non-trauma cases showed gas accumulations. Despite the exclusion of cases with visible decomposition signs, a putrefactive origin of gas was assumed in some cases. Gas accumulations are a frequent finding in PMCT with a higher incidence in (open) trauma cases. Even though a differentiation between putrefactive and traumatic gas accumulations is still difficult, knowledge of the circumstance surrounding the case may help identify the origin of gas.     

Quantitative analysis of pulmonary pathophysiology using postmortem computed tomography with regard to the cause of death

Radiological lung transparency depends on the air contents involved in respiratory function. The present study quantitatively investigated postmortem lung air distribution in forensic autopsy cases (n=135) using computed tomography (CT) to analyze cardiopulmonary pathophysiology in the death process, involving emphysema, congestion and edema. Combined analyses of the CT morphology and attenuation value (Hounsfield unit, HU) of the bilateral lungs, with reference to histopathology, could categorize CT findings (10-90 percentile mode/mean HU values) with regard to the causes of death as follows: (I) hyperaeration (mode/mean HU below -760/-560: emphysema) for obstructive pulmonary disease, starvation and hypothermia (cold exposure); (II) mostly normal aeration with partial ground glass opacification (mode/mean HU, -850 to -360/-700 to -380: partial congestion and edema), consisting of subtype II-a with peri-bronchial/-vascular opacity for mechanical asphyxia, drowning and fire fatality, and subtype II-b with decreased vascularity for gunshot head injury, cerebrovascular disease and hemopericardium; (III) hypoaeration to airless with predominant hypostatic ground glass opacification (mode/mean HU, -870 to 0/-720 to -200: mottled hypostatic congestion and edema) for blunt head/neck injury, intoxication, hyperthermia (heat stroke) and congestive heart failure; (IV) hypoaeration to airless with predominant hypostatic consolidation (mode/mean HU, -790 to 0/-520 to -70: intense hypostatic congestion with edema) for acute ischemic heart disease; and (V) airless to consolidated (mode/mean HU over -420/-370: segmental or multiple patchy consolidations with edema) for pneumonia. Mode HU represents the major alveolar status, while the mean HU reflects the whole lung air contents. CT data analysis is useful for quantitative evaluation of pulmonary pathology as a supplementary procedure.     

The significance of postmortem radiographs in infants

The radiographs of 108 infants were analyzed prospectively before autopsy to correlate radiographic findings with those found at the postmortem examination. There was poor correlation between radiographs and autopsy findings when pulmonary pathology was present, and there was no gut pathology when radiographs revealed portal venous air. The radiographs were most helpful when either bony abnormalities (that is, fractures or congenital abnormalities) or free air were found before autopsy.     

Virtopsy hemorrhage of the posterior cricoarytenoid muscle by blunt force to the neck in postmortem multislice computed tomography and magnetic resonance imaging

In forensic autopsies, one of the most important and common signs of violence to the neck is hemorrhages of the soft tissues. The Institute of Forensic Medicine in Bern evaluates the usefulness of postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) of forensic cases prior to autopsy. The aim of this study was to prove the sensitivity of postmortem MSCT and MRI in the detection of hemorrhages of the neck muscles. A full body scan prior to and a detailed scan of the explanted larynx after autopsy were performed. MSCT detected multiple fractures of the larynx. Detailed MRI was able to demonstrate the hemorrhage of the left posterior cricoarytenoid muscle. The minor hemorrhage of the right posterior cricoarytenoid muscle could not be detected with certainty. Although more experience is required, we conclude that combined MRI and MSCT examination is a useful tool for documentation and examination of neck muscle hemorrhages in forensic cases.     

Adipocere in postmortem imaging using multislice computed tomography (MSCT) and magnetic resonance imaging (MRI)

A body was found in a local river almost completely converted into adipocere. The corpse was identified as a 78-year-old male who was missed for 13 months. It was assumed that he committed suicide by drowning. The postmortem imaging findings utilizing multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) in this virtopsy case are presented with special focus on the radiologic appearance of adipocere. The loss of signal in MRI and hyperdensities in MSCT up to 1000 Hounsfield units, as well as the increased assessment of the intracranial structures compared with traditional autopsy, are presented.     

Digoxin-like immunoreactive substance in postmortem blood of infants and children

A digoxin-like immunoreactive substance (DLIS) has been reported in the serum of infants not receiving digoxin. This study was undertaken to determine if DLIS is present in the postmortem blood and tissues of infants or children and whether the endogenous substance could interfere with forensic toxicological analysis in suspected overdose. Ninety blood specimens taken from the heart at autopsy of children or infants were screened for DLIS using commercial radioimmunoassay kits. The average age at death in these cases was 8.6 months, the median age was 2 months. DLIS equivalent to 0.25 to 2.0 ng/mL digoxin was found in one third of the cases. The incidence of positive findings was 5/6 stillborns, 10/45 Sudden Infant Death Syndrome (SIDS), 10/15 deaths as a result of infection, 4/7 homicides, 1/8 deaths caused by congenital defects, and 0/9 accidental deaths. The body distribution of DLIS was investigated and highest levels were found in the liver. Findings of DLIS in blood were correlated with renal failure, (elevated vitreous urea nitrogen), electrolyte imbalance, and liver trauma. Apparent concentrations were in the equivalent therapeutic range of digoxin and would not be confused with accidental or intentional overdose with digoxin.     

脑血管造影在法医学尸体检验中的应用

脑血管造影作为诊断脑血管疾病的"金标准",目前已经广泛地应用于临床医疗活动中,并积累了丰富的理论和实践资料,是趋于成熟的技术方法。由于因脑血管疾病引发的法医学鉴定案件较为多见,故该技术近年开始应用于法医学,显示出在法医学实践中独特而重要的应用价值。本文对脑血管造影术在法医学中的应用价值进行综述,内容包括辅助定位血管病变或损伤部位、明确出血性质、指导尸体解剖与脑组织病理取材等,并在此基础上展望了该技术在法医学中的应用前景。     

Non-traumatic postmortem computed tomographic (PMCT) findings of the lung

PURPOSE: We attempted to obtain postmortem computed tomographic (PMCT) images of the lung in cases of non-traumatic death and describe the results to distinguish usual postmortem findings from those of specific thoracic causes of death. MATERIALS AND METHODS: Our subjects were a total of 150 consecutive non-traumatic cases with cardiopulmonary arrest on arrival who were examined by CT within 2h after certification of death between January 1993 and December 2001. PMCT images of the lung and the frequency of imaging findings (dependent density, ground glass attenuation (GGA), consolidation, pleural effusion, and endotracheal (or endobronchial) air defect) were retrospectively reviewed. Autopsy had been conducted in 16 of the cases. RESULTS: The causes of death and frequency percentages of dependent density, GGA, consolidation, pleural effusion, and endotracheal (or endobronchial) air defect were: 91 cases of acute heart failure (AHF) (69, 66, 24, 11, 14%), 23 cases of aortic dissection (57, 39, 4, 52, 0%), 11 cases of pneumonia (18, 82, 100, 45, 27%), 23 other specified cases (52, 30, 13, 17, 9%), and two unspecified cases (0, 0, 0, 50, 0%), [total respective frequency percentages were (60, 57, 25, 21, 12%)]. Autopsy confirmed that GGA on PMCT in AHF cases corresponded to pulmonary edema. CONCLUSION: When PMCT of the lung shows no other shadows than dependent density, further analysis is necessary to detect the cause of death.     

Dural hemorrhage of the tentorium on postmortem cranial computed tomographic scans in children

We analyzed four children with increased density of the tentorium on postmortem computed tomographic (CT) scans that suggested traumatic subarachnoid hemorrhage; but in which followup autopsy demonstrated an absence of subarachnoid hemorrhage. All cases had neither head injuries nor distinct intracranial abnormalities. Histological examinations showed extensive hemorrhage within the tentorium. These findings indicate that increased density of the tentorium on postmortem CT scan reflects 'dural hemorrhage' that may occur in children without intracranial abnormalities. Pediatricians and forensic pathologists should be aware of this phenomenon when using postmortem preautopsy CT scanning for diagnosis of child abuse.     

Sudden death caused by parasites: postmortem cerebral malaria discoveries in the african endemic zone

This survey presents several cases of sudden deaths in Africa, specifically in Cote d'Ivoire, where the postmortem diagnosis of human cerebral malaria was determined after autopsy followed by pathologic examination of the brain. It is thought that cerebral malaria may be the primary cause of sudden death in nonimmunized persons during or after traveling in such endemic areas of Africa. The target population is composed of tourists, business travelers, and sailors. Because death caused by cerebral malaria occurs so suddenly, it can lead to forensic issues. Therefore, in any cases involving sudden death, it is very important for the forensic scientist to do a systematic evaluation, including pathologic examination of brain tissue, to rule in or exclude cerebral malaria. This practice will reinforce and aid research in progress directed at developing a vaccine and elucidating the role of tumor necrosis factor in this disease. Furthermore, this study will alert the physician to the importance of an effective and well-followed prophylaxis.     

Virtopsy,a new imaging horizon in forensic pathology: virtual autopsy by postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI)--a feasibility study

Using postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI), 40 forensic cases were examined and findings were verified by subsequent autopsy. Results were classified as follows: (I) cause of death, (II) relevant traumatological and pathological findings, (III) vital reactions, (IV) reconstruction of injuries, (V) visualization. In these 40 forensic cases, 47 partly combined causes of death were diagnosed at autopsy, 26 (55%) causes of death were found independently using only radiological image data. Radiology was superior to autopsy in revealing certain cases of cranial, skeletal, or tissue trauma. Some forensic vital reactions were diagnosed equally well or better using MSCT/MRI. Radiological imaging techniques are particularly beneficial for reconstruction and visualization of forensic cases, including the opportunity to use the data for expert witness reports, teaching, quality control, and telemedical consultation. These preliminary results, based on the concept of "virtopsy," are promising enough to introduce and evaluate these radiological techniques in forensic medicine.     

Forensic imaging of projectiles using cone-beam computed tomography

In patients with gunshot injuries, it is easy to detect a projectile within the body due to the high-density of the object, but artefacts make it difficult to obtain information about the deformation and the exact location of the projectile in surrounding tissues. Cone-beam computed tomography (CBCT) is a new radiological imaging modality that allows radio-opaque objects to be localised and assessed in three dimensions. The full potential of the use of CBCT in forensic medicine has not yet been explored.In this study, three different modern projectiles were fired into the heads of pig cadavers (n = 6) under standardised conditions. Tissue destruction and the location of the projectiles were analysed separately using CBCT and multi-slice computed tomography (MDCT).The projectiles had the same kinetic energy but showed considerable differences in deformation behaviour. Within the study groups, tissue destruction was reproducible. CBCT is less severely affected by metallic artefacts than MDCT. Therefore CBCT is superior in visualising bone destruction in the immediate vicinity of the projectile and projectile deformation, whereas MDCT allows soft tissue to be evaluated in more detail.CBCT is an improved diagnostic tool for the evaluation of gunshot injuries. In particular, it is superior to MDCT in detecting structural hard-tissue damage in the immediate vicinity of high-density metal projectiles and in identifying the precise location of a projectile in the body.     

Comparison of computed radiography and multi-detector computed tomography in the detection of post mortem metacarpal index

This paper presents a disposable biosensor to detect serum alcohol concentration. The proposed biosensor is fabricated using the cross-linking method to immobilize Alcohol Dehydrogenase (ADH) and Nicotinamide Adenine Dinucleotide (NAD(+)) on the screen-printed electrode modified with Meldola's Blue (MB) absorbed on Nafion. It is based on the electrocatalytic properties of MB as an electron transfer mediator, which can catalyze the oxidation of NADH to NAD(+) at a low oxidizing potential, thus avoiding interferences due to the presence of oxidizable substances in the real serum samples. The biosensor response for alcohol is investigated in terms of pH, buffer solution, temperature and some interferents. It presents the good specificity, reproducibility, stability, accuracy and provides a fast response. The biosensor has been satisfactorily used for the measurement of serum alcohol.