利用额窦影像进行个体识别的研究进展

鉴于额窦不规则气腔形态的高度特异性、成熟后形态不变的稳定性以及放射学技术在临床的广泛应用,额窦影像已成为法医学个体识别的重要研究对象.利用额窦影像进行个体识别已具有法庭意义.当DNA和指纹等传统个体识别方法应用受限或无法有效进行,或缺乏相应的牙科记录等情况时,额窦影像对比是有效的个体识别替代方法.多种影像资料都可用于额...     

Craniofacial identification by comparison of antemortem and postmortem radiographs: two case reports dealing with burnt bodies

Two cases of positive identification of burnt bodies by radiographic comparison are reported. They emphasize that antemortem radiographs of the head are an important but sometimes overlooked source of information which can frequently provide useful objective data for comparison purposes. A positive identification can easily be achieved by medical examiners through visual comparison of the antemortem with the postmortem cranial and facial structures, even of bodies severely damaged by fire. In these bodies the radiographs of the skull can graphically depict structures which are often unique to the individual, such as the frontal sinus pattern and the morphology of dental restorations. However, the process of identification through radiographs is appropriate only in burnt bodies in which antemortem radiographs of the alleged deceased are available for comparison and unique craniofacial structures are still present on the body in a well-preserved state or at least not completely destroyed by fire, depending on the extent of the burn injury. Matching of corresponding features seems preferable to other methods of personal identification such as skull-photo superimposition, morphometric analysis, and/or other computer-aided methods since these techniques need trained personnel, as well as expensive equipment which is not invariably available in the medical examiner's office or department of anthropology.     

Post-mortem radiological CT identification based on classical ante-mortem X-ray examinations

Radiological identification is important in forensic medicine. Identification using comparison of individualising structures with ante- and post-mortem conventional radiographs has been known for a long time. New radiological procedures such as computed tomography (CT) and magnetic resonance imaging (MRI) are being increasingly used for identification. In this paper, a new comparative approach using various radiological methods is described and its application demonstrated. This new approach is the comparison of ante-mortem conventional radiographs with projected images calculated from post-mortem CT data. The identification procedure will be illustrated with reference to the frontal sinus and the pelvis.     

Application of superimposition-based personal identification using skull computed tomography images

Superimposition has been applied to skulls of unidentified skeletonized corpses as a personal identification method. The current method involves layering of a skull and a facial image of a suspected person and thus requires a real skeletonized skull. In this study, we scanned skulls of skeletonized corpses by computed tomography (CT), reconstructed three-dimensional (3D) images of skulls from the CT images, and superimposed the 3D images with facial images of the corresponding persons taken in their lives. Superimposition using 3D-reconstructed skull images demonstrated, as did superimposition using real skulls, an adequate degree of morphological consistency between the 3D-reconstructed skulls and persons in the facial images. Three-dimensional skull images reconstructed from CT images can be saved as data files and the use of these images in superimposition is effective for personal identification of unidentified bodies.     

Use of Craniofacial Superimposition in Historic Investigation

A skeleton discovered in Grand Forks, North Dakota was purported to belong to Clelland “Clell” Miller, a James‐Younger gang member, who was killed during the Northfield Bank robbery on September 7, 1876. A 3‐D image from a computer tomography (CT) scan of the skull was obtained, and a craniofacial superimposition was conducted to determine if the skull could belong to Miller. The superimposition method used in this case was to overlay the CT image of the skull onto Miller's postmortem photograph. In addition to the craniofacial superimposition, the images were juxtaposed to compare similarities or differences in facial morphology between the skull and photograph. Superimposition methods can be used to exclude identifications; however, they should not be used as a conclusive method for identification. In this case, there were sufficient similarities between the skull and Miller's photograph; therefore, the skull could not be eliminated as possibly being that of Miller.     

Stab injuries of the skull and brain

A few cases of skull and brain stab wounds are described and the clinicodiagnostic problems discussed. The injuries often remain unrecognized because the external wound often appears harmless, there are no neurological symptoms, or the clinical picture is interpreted as drunkenness, blunt injury or as another disease. The importance of a precise physical examination of the whole patient's head is pointed out. The refined methods used in modern radiodiagnostics of the skull are the most helpful in correctly recognizing these injuries; there are reports of patients with severe injuries who recovered when the correct diagnosis had been established.     

Testing the reliability of frontal sinuses in positive identification

The use of frontal sinus radiographs in positive identification has become an increasingly applied and accepted technique among forensic anthropologists, radiologists, and pathologists. From an evidentiary standpoint, however, it is important to know whether frontal sinus radiographs are a reliable method for confirming or rejecting an identification, and standardized methods should be applied when making comparisons. The purpose of the following study is to develop an objective, standardized comparison method, and investigate the reliability of that method. Elliptic Fourier analysis (EFA) was used to assess the variation in 808 outlines of frontal sinuses by calculating likelihood ratios and posterior probabilities from EFA coefficients. Results show that using EFA coefficient comparison to estimate the probability of a correct identification is a reliable technique, and EFA comparison of frontal sinus outlines is recommended when it may be necessary to provide quantitative substantiation for a forensic identification based on these structures.     

Identification of a Carbonized Body Using Implanted Surgical Plates: The Importance of Computed Tomography

In addition to clinical examination, forensic odontologists can use diagnostic imaging as an auxiliary method for identification. This paper reports a case where forensic odontologists from the Afrânio Peixoto Legal Medicine Institute in Rio de Janeiro (Brazil) positively identified a carbonized and partially calcined body using oral and maxillofacial imaging. The cadaver showed several metallic plates fixed with metallic screws on bones of the neurocranium and viscerocranium. Family members provided spiral computed tomography scans of the skull and a panoramic radiograph that were acquired after an accident that required surgical procedures. Comparative analysis between the clinical exam and the maxillofacial images demonstrated complete coincidence, confirming the victim's identity. Dactyloscopy, which is the most commonly used method of identification, was not possible because of the body carbonization. Thus, diagnostic imaging, especially computed tomography, was essential for elucidation of this case.     

An investigation into the accuracy and reliability of skull-photo superimposition in a South African sample

One of the aims of forensic science is to determine the identities of victims of crime. In some cases the investigators may have ideas as to the identities of the victims and in these situations, ante mortem photographs of the victims could be used in order to try and establish identity through skull-photo superimposition. The aim of this study was to evaluate the accuracy of a newly developed digital photographic superimposition technique on a South African sample of cadaver photographs and skulls. Forty facial photographs were selected and for each photo, 10 skulls (including the skull corresponding to the photo) were used for superimposition. The investigator did not know which of the 10 skulls corresponded to the photograph in question. The skulls were scanned 3-dimensionally, using a Cyberware? Model 3030 Colour-3D Scanhead scanner. The photos were also scanned. Superimposition was done in 3D Studio Max and involved a morphological superimposition, whereby a skull is superimposed over the photo and assessed for a morphological match. Superimposition using selected anatomical landmarks was also performed to assess the match. A total of 400 skull-photo superimpositions were carried out using the morphological assessment and another 400 using the anatomical landmarks. In 85% of cases the correct skull was included in the possible matches for a particular photo using morphological assessment. However, in all of these cases, between zero and three other skulls out of 10 possibilities could also match a specific photo. In the landmark based assessment, the correct skull was included in 80% of cases. Once again, however, between one and seven other skulls out of 10 possibilities also matched the photo. This indicates that skull-photo superimposition has limited use in the identification of human skeletal remains, but may be useful as an initial screening tool. Corroborative techniques should also be used in the identification process.     

Personal Identification Using the Frontal Sinus*

Abstract: The frontal sinuses are known to be unique to each individual; however, no one has tested the independence of the frontal sinus traits to see if probability analysis through trait combination is a viable method of identifying an individual using the frontal sinuses. This research examines the feasibility of probability trait combination, based on criteria recommended in the literature, and examines two other methods of identification using the frontal sinuses: discrete trait combinations and superimposition pattern matching. This research finds that most sinus traits are dependent upon one another and thus cannot be used in probability combinations. When looking at traits that are independent, this research finds that metric methods are too fraught with potential errors to be useful. Discrete trait combinations do not have a high enough discriminating power to be useful. Only superimposition pattern matching is an effective method of identifying an individual using the frontal sinuses.     

轻型颅脑损伤的损伤程度评定探讨

根据１８５例轻型颅脑损伤的法医学鉴定，证实颅骨骨折是颅内并发症的危险因素，支持临床观点。３１例颅骨骨折组，经ＣＴ发现颅内并发症的２０例，以ＥＤＨ和ＳＤＨ多见．行ＣＳＦ检查对诊断有价值．同时提出轻型颅脑损伤分级标准，依此明确轻伤评定等级．     

Skeletal identification using the frontal sinus region: a retrospective study of 39 cases

The importance of identification using the frontal sinus has been previously demonstrated in case reports. In this study, 39 cases of identification using frontal sinus comparison from the Ontario Chief Coroner's Office were reviewed and differences between antemortem and postmortem radiographs examined. All cases involved decedents older than twenty years. Three cases were rejected due to poor antemortem and postmortem film quality. One subject had no frontal sinus. Thirty-five cases provided conclusive postmortem to antemortem pattern matches. Sixteen cases also yielded metric (quantitative) matches. Duration between antemortem and postmortem radiographic examinations, age, gender, and cause of death did not affect the ability to obtain a match. This is the largest study undertaken on actual cases and demonstrates the validity of frontal sinus pattern matching for forensic identification.     

To Crack or Crumble: Use of the Thin Skull and Crumbling Skull Rules

The psycholegal and medicolegal assessment of injury-related physical and psychological impairments and disabilities is fraught with difficulties, including assessing for physical and psychological risk factors. In the injury litigation context, in Canada, issues related to pre-injury physical and psychological risk factors are best captured by the thin skull and crumbling skull rules. A review of court cases in which these rules have been considered suggests that the rules are not applied consistently. This inconsistency in the application of these rules has contributed to conflicting determinations of cause and damages across trial court, appeal court, and Supreme Court cases. This article provides operational definitions of the thin skull and crumbling skull rules, presents a case that involves a series of court decisions that exemplify the difficulties associated with the application of these rules, and provides recommendations for more effective application of the two rules.     

Role of orthopedic implants and bone morphology in the identification of human remains

When conventional methods of identification, such as visual recognition and dental comparison, cannot be used to identify a deceased person, it becomes necessary to consider alternative methods. The presence of an orthopedic implant in a body may assist identification if ante-mortem medical records are available for comparison. Another method of identification involves comparison of ante-mortem and postmortem radiographs. Eight cases are reported from Forensic Science SA where the presence of orthopedic implants and/or ante-mortem radiographs were used to try to establish identification. In six cases, positive identification was established, and in two cases with upper limb orthopedic implants, the bones remained unidentified. Manufacturers were unable to provide any information about the distribution and use of the implants that could be of use with identification, as there are no requirements in Australia for individual medical implants to be tracked. Such a system has the potential to aid postmortem identification if serial codes were etched onto implants that could then be traced to manufacturers, surgeons, and recipients of these devices.     

Identifying Fatal Head Injuries on Postmortem Computed Tomography Using Convolutional Neural Network/Deep Learning: A Feasibility Study

Postmortem computed tomography (PMCT) is a relatively recent advancement in forensic pathology practice that has been increasingly used as an ancillary investigation and screening tool. One area of clinical CT imaging that has garnered a lot of research interest recently is the area of “artificial intelligence” (AI), such as in screening and computer-assisted diagnostics. This feasibility study investigated the application of convolutional neural network, a form of deep learning AI, to PMCT head imaging in differentiating fatal head injury from controls. PMCT images of a transverse section of the head at the level of the frontal sinus from 25 cases of fatal head injury were combined with 25 nonhead-injury controls and divided into training and testing datasets. A convolutional neural network was constructed using Keras and was trained against the training data before being assessed against the testing dataset. The results of this study demonstrated an accuracy of between 70% and 92.5%, with difficulties in recognizing subarachnoid hemorrhage and in distinguishing congested vessels and prominent falx from head injury. These results are promising for potential applications as a screening tool or in computer-assisted diagnostics in the future.     

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.     

Skeletal height reconstruction from measurements of the skull in indigenous South Africans

Stature reconstruction is important as it provides a forensic anthropological estimate of the height of a person in the living state; playing a vital role in the identification of individuals from their skeletal remains. Regression formulae for stature estimation have been generated for indigenous South Africans based on measurements of long bones of upper and lower extremities and the calcaneus. Since these bones are not always available for forensic analysis, it became necessary to use other bones such as the skull for stature estimation. The aim of the present study was to investigate the usefulness of certain measurements of the skull of indigenous South Africans in the estimation of adult stature. Ninety-nine complete skeletons obtained from the Raymond A. Dart Collection, School of Anatomical Sciences of the University of the Witwatersrand, were used. Total skeletal height (TSH) was calculated for each skeleton using the Fully's (anatomical) method. Furthermore, six variables were measured on each skull. TSH was regressed onto these cranial measurements in order to obtain regression formulae. The correlation coefficients obtained ranged between 0.40 and 0.54. The range of the standard errors of estimate from the current study (4.37 and 6.24) is high in comparison to that obtained for stature estimation based on intact long bones and the calcaneus. Therefore, the equations presented in this study should be used with caution in forensic cases when only the skull is available for human identification.     

The death of Adolf Hitler--forensic aspects

The death of Adolf Hitler is one of the unsolved mysteries of the twentieth century. Numerous historians and journalists have attempted to piece together the details, but despite the interest in the forensic literature regarding the identification of the body, there has not been much scientific debate about the alleged cause of death--cyanide poisoning, gunshot injury, or both. The available literature concerning Hitler's cause of death is incomplete because the toxicological analysis has not been performed and because the skull bone fragment with a gunshot wound possibly from Hitler's corpse has not been properly examined. This has given basis for various theories, which are reviewed. We believe that mtDNA analysis of the skull fragments and of Hitler's jaw, now filed in Moscow, and samples from maternal relatives of Hitler are crucial linking the skull fragment with the gunshot wound to Hitler.     

Fatal high cervical spinal cord injury in an automobile accident complicating os odontoideum

We report a case where spinal instability from incomplete fusion of the dens of C2 (os odontoideum) allowed anterior displacement of the skull and first cervical vertebra following right frontal impact against the A pillar in an automobile accident. Resultant crushing and laceration of the spinal cord occurred at the level of C1 and C2. Without either radiographic investigation or detailed examination of the spine, the fatal injury might have been overlooked and death attributed to acute alcoholic poisoning because the blood alcohol level was .613%.