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。     

外伤性椎间盘突出时间与CT值改变的相关性

目的探讨外伤性椎间盘突出发生时间与CT值改变的相关性。方法分别对198例自伤性椎间盘突出疝出部髓核CT值(表示为A)和未疝出部髓核CT值(表示为B)进行测量,计算出二者的差值(即判定参数),分析判定参数与椎间盘突出时间的关系。结果判定参数与椎间盘突出时间具有相关性,其差异具有统计学意义,判定参数在-12～-40HU之间,平均为-25.8HU(AB)时,椎间盘突出时间在6至12个月;判定参数在37～289HU之间,平均为96.1HU(A>B)时,椎间盘突出时间在12个月以上。结论根据判定参数可判定外伤性椎间盘突出发生的大体时间。     

医源性新生儿肺气肿—附3例分析

报道了3例新生儿肺气肿,均发现实质性肺气肿、间质性肺气肿和大泡性肺气肿,其中1例伴有气体广泛蓄积于软组织间隙,表现为自肺间隔开始,经肺门至纵隔,并直达胸、颈、腹、腹股沟等处皮下组织和阴囊。所报道的新生儿肺气肿原因被认为是抢救时加压吸氧造成。     

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.     

脑死亡脑外器官病理变化的实验性研究

选用34只家猫研究脑死亡后脑外器官（心、肺、肝、肾）的病理学变化。经任内持续加压造成脑死亡模型,根据人工维持心跳和呼吸的时间分3组。结果脑死亡后出现：（1）缺血性心肌病变,心内膜下出血,心肌局灶性坏死及线粒体、微丝破坏;（2）肺淤血,水肿,间质炎症;（3）肝小叶中央带、中间带缺血性病变;（4）肾近曲小管缺血性病变。     

Postmortem chest computed tomography for the diagnosis of drowning:a feasibility study

It may be difficult to distinguish the cause of death in drowning cases without specific findings. The aim of this study was to explore the forensic value of thoracic postmortem computed tomography (PMCT) using routine images and three-dimensional (3D) image reconstructions. The imaging data of PMCT examinations of six drowning cadavers, aged 21–54 years, were analyzed. Twelve victims of sudden death from coronary artery disease (CAD) were chosen as a control group. After 3D bilateral lung images were reconstructed using image processing software, an interactive medical image control system was used to measure and analyze parameters including lung volume, lung volume ratio, mean CT value of the whole lung, and lung CT value distribution curves. Lung volume and lung volume ratio were used to assess the shape changes of the lung. Lung CT value distribution curves showed the corresponding number of pixels of the different CT values in the lung image. Lung volume was not significantly larger in drowning cases (mean 2 958 cm³) than in controls (mean 2 342 cm³). Lung volume ratio values in the drowning group (mean 0.3156) were greater than those in the control group (mean 0.2763); (P = 0.02). There was no significant difference between the drowning and control group in the mean CT value of the whole lung. There were differences between lung CT value distribution curves in drowning victims and controls, with drowning victims showing a single peak and CAD cases showing a bimodal distribution. Thoracic PMCT is helpful for the forensic medical diagnosis of drowning. Lung volume ratio and lung CT value distribution are potential indicators to distinguish between drowning and CAD.     

Is Differentiation of Frequently Encountered Foreign Bodies in Corpses Possible by Hounsfield Density Measurement?

Abstract:  The radiological determination of foreign objects in corpses can be difficult if they are fragmented or deformed. With multislice computed tomography, radiodensities—referred to as Hounsfield units (HU)—can be measured. We examined the possibility of differentiating 21 frequently occurring foreign bodies, such as metals, rocks, and different manmade materials by virtue of their HU values. Gold, steel, and brass showed mean HU values of 30671–30710 (upper measurable limit), mean HU values for steel, silver, copper, and limestone were 20346, 16949, 14033, and 2765, respectively. The group consisting of objects, such as aluminum, tarmac, car front-window glass, and other rocks, displayed mean HU values of 2329–2131 HU. The mean HU value of bottle glass and car side-window glass was 2088, whereas windowpane glass was 493. HU value determination may therefore help in preautopsy differentiation between case-relevant and irrelevant foreign bodies and thus be useful for autopsy planning and extraction of the objects in question.     

Post-traumatic venous and systemic air embolism associated with spinal epidural emphysema: multi-slice computed tomography diagnosis

A 30-year-old man was admitted with chest trauma after a road traffic accident. The patient was paraplegic and suffered from transient monoparesia of the left arm. The chest X-ray revealed a severe right tension pneumothorax and thoracic spine fractures. Emergency right thoracic drainage was carried out followed by angiography. Unfortunately the patient died and an autopsy was not permitted. Consequently post-mortem multi-slice computed tomography (MSCT) was performed, revealing presence of air inside the right cerebral arteries, bilateral pneumothorax accompanied by a severe right tension pneumothorax, bilateral haematic pleural effusion, pneumomediastinum and bilateral lung contusions. Air was also observed within the right coronary artery, ascending aorta and right ventricle. Thoracic and cervical spinal epidural emphysema were diagnosed. Venous air embolism followed by arterial air embolism producing paradoxical embolism was diagnosed. To the best of our knowledge, this is the first case illustrating by post-mortem MSCT such simultaneous complications after chest trauma as spinal epidural emphysema and cerebral and coronary air embolism.     

Differential accumulation of pulmonary and cardiac mast cell-subsets and eosinophils between fatal anaphylaxis and asthma death: a postmortem comparative study

The distribution profile of infiltrated mast cell-subpopulations and eosinophils in the lung and heart sections of the patients who died of severe allergic hyperresponsiveness, was investigated. Four study groups were designed comprising 9 cases who died in systemic anaphylaxis (Group I), 10 asthmatic individuals whose death were assigned to acute and severe bronchial asthma (Group II), 10 asthmatic cases who died from non-immunological diseases (Group III). Twenty consecutive autopsies of non-allergic subjects who died of unnatural causes (Group IV) served as control group in this study. Utilizing antibodies against human tryptase and chymase and a double immunohistochemical staining method, we distinguished successfully all three subsets of mast cells (MC), MC-TC (containing both tryptase and chymase), MC-T (containing only tryptase) and MC-C (containing only chymase) types, subdivided on the basis of the protease compositions of their secretory granules. In order to immunostaining eosinophils, we used antibody to major basic protein as a marker. We also measured postmortem blood tryptase, specific and total serum IgE. The intriguing finding of this study was the marked differences of cellular composition in the lung between fatal anaphylaxis and asthma death. Significant augmentation of MCs infiltrated in lung and heart sections of anaphylaxis patients and drastic infiltration of bronchial eosinophils in asthmatic death and consequent release of their related inflammatory mediators might explain the differential expression of the associated symptoms in these two groups. The anaphylactic deaths did show neither emphysema nor significant mucous bronchial secretions whereas all asthmatic deaths did. The degree of pulmonary congestion and edema was also more severe in anaphylaxis. This corresponded with the histological findings and the location and number of mast cell-subsets and eosinophils in the different compartments of the lungs. We have demonstrated that the third type of mast cell MC-C is only found in the lungs in anaphylactic deaths. The practical consequence of our study will be that it is now possible to confirm a suspicion of anaphylaxis death not only by measurements of serum mast cell tryptase, but also by immunohistochemical methods.     

Morphology of acute lung injuries in mechanic trauma

The lungs from 60 subjects who had died of polytrauma were studied morphologically. The heads of the corpses were not injuried. The aim of the study was investigation of characteristics and time of development of structural changes associated with lung injury. Early structural changes in trauma were disorders of circulation including microcirculation, acute emphysema, distelectases and atelectases, injury of bronchial and bronchiolar mucosa. Pulmonary edema and systemic inflammatory reaction emerge in the first hours after trauma.     

Histological examination of the temporal bone in medicolegal cases of asphyxia

Histological findings of the temporal bone in 23 autopsy cases of various asphyxial fatalities were studied. The temporal bones of 12 cases who died of tumors including mammary cancer, gastric cancer, myxoma of heart and craniopharyngioma, the bones of 3 cases of heart attack and the bones of 17 cases who died of various poisoning (barbiturate, amphetamine, paraquat and alcohol) were used as controls. In drowning, the primary finding was hemorrhage in the mastoid air cells of the bilateral temporal bones. In cases of strangulation by ligature, hemorrhage and edema of the cochlear duct in the inner ear as well as hemorrhage in the mastoid air cells were demonstrated bilaterally. In contrast, congestion and edema in the mastoid air cells and inner ear were found in cases of manual strangulation but there was no hemorrhage. From these results, the histological examination of the temporal bone is useful as an adjunct procedure for diagnosing the cause of asphyxia. Differentiation between drowning, strangulation by ligature and manual strangulation may be possible by observing hemorrhages or their absence in the mastoid air cells and inner ear.     

Accuracy of facial soft tissue thickness measurements in personal computer-based multiplanar reconstructed computed tomographic images

The purpose of this study was to determine the precision and accuracy of facial soft tissue measurement using personal computer (PC)-based multiplanar reconstructed (MPR) computed tomography (CT) images and to evaluate the effect of the various CT scanning protocols on the facial soft tissue thickness measurement. Thirteen different CT imaging protocols were used to image a cadaver head. MPR reformations and three-dimensional (3D) reconstructions viewed on a laptop PC were used to make measurements at six specific sites on each set of images. These measurements were compared to physical measurements at the same sites. Increasing the slice thickness resulted in decreased image quality. Within the same slice thickness, increasing the pitch ratio in the spiral mode, resulted in decreasing image quality. The image quality of conventional CT scanning was relatively poorer than that of the spiral CT scanning. However, the mean deviation from the physical measurement was within 0.43 mm in every instance. This mean deviation was quite small and clinically acceptable for measuring the soft tissue thickness of the facial area. PC-based MPR CT images of the face using routine scanning CT protocols can be used to accurately measure soft tissue thickness in the facial region. However, for more fine and accurate data collection, scanning protocols with slice thicknesses less than 5mm, and a spiral/helical mode pitch less than 2:1 are recommended.     

Diagnostic dilemma of sudden deaths due to acute hemorrhagic pancreatitis

Sudden death due to acute pancreatitis has been rarely determined. A review of 3305 autopsies performed between 1991 and 2001 at the Council of Forensic Medicine found 12 cases (0.36%) with sudden death due to acute hemorrhagic pancreatitis without symptoms. A history of chronic alcohol ingestion was obtained from family in four cases (33%), and no stones were found in the bile ducts or in the gall bladders. During the autopsies, hemorrhage and edema were localized on the head of the pancreas in three cases and the whole pancreas in nine cases. The most common extrapancreatic pathology was found in the lung including pulmonary edema, alveolar hemorrhage, pleural effusion, and pulmonary congestion. There was no correlation between pulmonary and pancreatic damage. It is suggested that the forensic pathologists who are dealing with sudden unexpected death must not ignore the examination of pancreatic and extrapancreatic regions to avoid missing acute pancreatitis.     

Pneumomediastinum and soft tissue emphysema of the neck in postmortem CT and MRI; a new vital sign in hanging?

Spontaneous pneumomediastinum commonly occurs in healthy young men or parturient women in whom an increased intra-alveolar pressure (Valsalva maneuver, asthma, cough, emesis) leads to the rupture of the marginal pulmonary alveoli. The air ascends along the bronchi to the mediastinum and the subcutaneous space of the neck, causing cervico-fascial subcutaneous emphysema in 70-90% of cases. Ninety-five forensic cases, including five cases of hanging, were examined using postmortem multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) prior to autopsy until December 2003. This paper describes the findings of pneumomediastinum and cervical emphysema in three of five cases of hanging. The mechanism of its formation is discussed based on these results and a review of the literature. In conclusion, when putrefaction gas can be excluded the findings of pneumomediastinum and cervical soft tissue emphysema serve as evidence of vitality of a hanged person. Postmortem cross-sectional imaging is considered a useful visualization tool for emphysema, with a great potential for examination and documentation.     

Morphologic determinants of asphyxia in lungs: a semiquantitative study in forensic autopsies

Asphyxia is a name given to different kinds of lesions that can produce similar histologic findings. Thus, because of the varied nature of the different kinds of lesions, as well as the incidence of similar qualitative histologic findings with different causes, the aim of this work was to study special kinds of injuries with particular subsequent impairment. These include some diagnostic problems of sudden death of natural causes, including aspiration, suffocation, drowning, and strangulation. Ranking was made of 167 victims based on the diagnosis as having: aspiration (n = 35), suffocation (n = 88), drowning (n = 27), and strangulation (n = 17). Stepwise discriminant analysis of the resulting data showed that lung necropsies from victims of these four events could be distinguished from one another. Statistical differences among the four groups were observed for eight morphologic parameters. A robust discriminant function permitted an adequate classification of the four groups of disease in 85.03% of the cases. Lung autopsies with congestion, septal hemorrhage, and foreign body showed a specificity of 100% for victims of aspiration, whereas ductal overinsufflation, interstitial edema, and bronchiolar constriction showed a specificity of 81.8% in victims of suffocation. Intraalveolar edema and dilatation of the alveolar spaces with secondary compression of the septal capillaries characterized drowning. Victims of strangulation showed a strong alveolar hemorrhage, with alveolar collapse and overinsufflation, associated with bronchiolar dilatation. It is concluded that semiquantitative analysis of lung autopsies might be a useful supplementary histologic criterion to support the diagnosis of asphyxia.     

Fatal acute alcohol intoxication in an ALDH2 heterozygote: a case report

On an evening in November, a 25-year-old man was found dead in his bedroom. There were many empty snap-out sheets for flunitrazepam tablets in the trash at his bedside. He had been beaten by a gang of young people earlier in the morning of the same day. At the medico-legal autopsy, although there were many bruises and/or abrasions on the whole body, only slight subdural hemorrhage was observed, and none of them was thought to be the cause of death. Flunitrazepam and its metabolites were not detected in his body fluid by gas chromatography-mass spectrometry (GC-MS). Marked lung edema and a severe congestion of organs were observed. His blood alcohol concentration from the femoral vein was 2.00 mg/ml. Fatal cases of acute alcohol intoxication usually have shown higher alcohol concentration (2.25-6.23 mg/ml). Although the genotype of aldehyde dehydrogenase 2 (ALDH2) has not previously been mentioned as a contributing factor in determining the cause of death, in this case the genotype of ALDH2 was ALDH2*1/2 and thus is important. Those who possess the ALDH2*2 gene show high concentrations of acetaldehyde (AcH) at even comparatively lower alcohol levels. Consequently, the cause of death was considered to be acute alcohol intoxication including AcH poisoning.     

Ultrastructure of acute ammonia toxicity in the human lung

A tanker truck carrying anhydrous ammonia (NH3) fell off a freeway, releasing a dense cloud of NH3 gas, killing several people. The driver was dead upon impact. To our knowledge, pulmonary NH3 toxicity in humans has not been studied previously by electron microscopy (EM). Therefore, in two cases, the paraffin-embedded tissue blocks of lung were deparaffinized and reembedded in plastic for 1-mu sections and EM examination. The lung tissue of a third case, the truck driver, was similarly processed as a control. Light-microscopic pulmonary findings in the acute NH3 deaths included denudation of the tracheobronchial epithelium, edema of the lamina propria, and marked alveolar edema, congestion, and hemorrhage. In contrast, in the truck driver's lungs, the bronchial epithelium was intact, and there was no gross odor of NH3. Massive pulmonary hemorrhages in his lungs were attributed to trauma rather than NH3 inhalation. EM examination of the lungs of the truck driver showed no discernible toxic alterations in either the capillary endothelial cells or the Type I or II alveolar epithelial cells, and alveolar and capillary basement membranes were intact. In contrast, EM study of the lungs from two individuals dying acutely of NH3 inhalation showed marked swelling and imbitional edema of Type I alveolar epithelial cells; however, alveolar basement membranes and capillary endothelial cells appeared as usual. These electron-microscopic findings demonstrate the Type I epithelial cell to be the target cell of acute alveolar wall injury in NH3 inhalation.     

Toxicological findings in a multi-drug death involving propoxyphene, caffeine, phenacetin, acetaminophen and salicylate

The toxicological findings of a multi-drug related fatal poisoning are described here. A 35-year-old Caucasian male found dead on the kitchen floor was a known user of abused drugs and had been taking aspirin alone or in combination with phenacetin and caffeine for the relief of joint pains. The gross examination of the organs at autopsy revealed slight grooving of the uncus and various stages of necrosis in the renal papillae. Histological examination confirmed the gross appearance of pulmonary congestion and edema, cerebral edema and interstitial nephritis of the tubules. Toxicological evaluation of the blood and urine samples disclosed the presence of propoxyphene (51 and 250 mg/l), salicylate (185 and 2750 mg/l), caffeine (16 and 37 mg/l), and phenacetin (9.6 and 20 mg/l). Furthermore, acetaminophen also was present in the plasma (54 mg/l) and urine. A gas liquid chromatographic method for simultaneous analysis of phenacetin and caffeine utilizing a nitrogen phosphorus detector was proposed.     

Examinations to phenomenon of shock-lung (author's transl)]

The pathogenesis of shock lung as well as the success of therapy in this condition was studied in 79 cases of extrathoracic trauma. The water-, hemoglobin-, and DNA contents of the lungs were measured in order to determine the extent of edema, the rate of perfusion, and proliferation. The cases were divided into two groups according to whether they had or had not received medical therapy before death. The data from these two groups were compared using statistical methods in which time of survival was especially taken into account. The fluid balance, pO2, pCO2, central venous pressure, pH of the serum, total serum protein and serum creatinine were also studied in these cases. Results of the study are as follows. Three phases of the posttraumatic syndrome of shock-lung could be distinguished: phase I (initial phase): blood perfusion is increased, edema is beginning to form, and medical treatment has not yet begun. Phase II (early phase = sydrome of early respiratory failure): pulmonary edema is developing rapidly while perfusion is decreasing. Phase III (late phase = syndrome of late respiratory failure): proliferative changes predominante and the edema is still increasing. The mean weight of the lungs was 397 g (s = 170) in phase I, 774 G (S = 361) In phase II, and 1124 g (s = 310) in phase III. The survival times correlated significantly and positively with the amount of water and DNS in the lungs and significantly and negatively to the amount of hemoglobin in the lungs. Thus, increasing pulmonary edema and increasing proliferative changes occurred with decreasing pulmonary perfusion. This correlation was even noted in groups of patients who had not received medical treatment and whose survival times were short. In treated cases, the fluid balance was significantly and negatively correlated to the total serum protein.     

Apoptotic and necrotic brain lesions in a fatal case of carbon monoxide poisoning

A 41-year-old man was accidentally exposed to carbon monoxide (CO) gas and found in a state of cardiopulmonary arrest while he took bath. After admission, he was resuscitated and underwent artificial ventilation in a comatose state and died about 19h later. Computed tomography (CT) examination disclosed bilateral low density area in the basal ganglia and the thalamus, a well-known finding in the CO intoxication. Necropsy, histological examination, DNA ladder assay gave the first line of evidence for the presence of apoptosis as well as necrosis in the human case of CO intoxication. TdT-mediated dUTP-biotin nick-end labeling (TUNEL) positive apoptotic cells were more predominant in the CA2 area than in CA1 area. There is general co-relation between the ratio of TUNEL-positive cells and the DNA laddering on the agarose gel. Basal ganglia and thalamus, which showed bilateral low density area in CT, were revealed to be severe edema. The two types of cell death occurred in the cortex, basal ganglia, hippocampus, thalamus, and cerebellum. Hypoxia caused by CO-hemoglobin formation alone cannot explain the phenomena.