122例鼻部骨折X线和CT诊断的法医学分析

目的　探讨CT在鼻部骨折诊断中的优点。方法　观察 12 2例鼻损伤伤者的鼻部CT和普通X线片 ,对鼻部诸骨骨折进行对比分析。结果　 12 2例鼻部骨折 (鼻骨骨折 3 2例 ,上颌骨额突骨折 3 3例 ,鼻中隔骨折 9例 ,多发性骨折 48例 )均经CT认定。其中 40例因X线片漏诊直接通过高分辨率鼻骨CT薄层扫描认定 ;82例通过鼻骨侧位X线片显示有鼻部骨折 ,因存在骨折类型认定不准确和 /或有漏诊鼻部其它部位骨折可能 ,通过鼻骨CT认定。结论　鼻骨侧位X线片易漏诊、误诊鼻部骨折 ;鼻骨CT能避免鼻部诸骨骨折的漏诊及误诊 ,且骨折认定准确。     

Pulp volume quantification methods in cone-beam computed tomography for age estimation: A critical review and meta-analysis

The secondary dentin deposition that occurs after the tooth formation process results in a decrease in pulp cavity volume in adolescents and adults. The purpose of this critical review was to correlate pulpal and/or dental volume on cone-beam computed tomography (CBCT) with chronological age approximation. A subobjective was to investigate which methodology and CBCT technical parameters would be most appropriate to evaluate this correlation. This critical review followed the PRISMA guidelines, and it was conducted by a search through PubMed, Embase, SciELO, Scopus, Web of Science, Cochrane Library databases, as well as gray literature. Primary studies that used pulp volume, or pulp chamber to tooth volume ratio measured using CBCT were included. Seven hundred and eight indexed and 31 non-indexed records were identified. A qualitative analysis was performed including 25 selected studies with a total of 5100 individuals, age ranging from 8 to 87 years without sex predilection. The most used method was pulp volume/tooth volume. CBCT voxel size ranged between 0.09 and 0.5. Manual segmentation associated with threshold algorithms was used in most of the studies. Correlation between the pulp volume/tooth volume ratio was moderate: −0.66 for the upper central incisors, −0.59 for upper canines and −0.56 for lower canines. High heterogeneity was observed among the studies. It is concluded that pulp volume should be used with caution in age estimation. Evidence supports the preferable use of upper incisors with pulp volume/tooth volume ratio for age estimation. There is not enough evidence that voxel size interferes in age estimation by pulp volume.     

Correlation between skeletal trauma and energy in falls from great height detected by post-mortem multislice computed tomography (MSCT)

Fatal falls from great height are a frequently encountered setting in forensic pathology. They present – by virtue of a calculable energy transmission to the body – an ideal model for the assessment of the effects of blunt trauma to a human body.As multislice computed tomography (MSCT) has proven not only to be invaluable in clinical examinations, but also to be a viable tool in post-mortem imaging, especially in the field of osseous injuries, we performed a MSCT scan on 20 victims of falls from great height. We hereby detected fractures and their distributions were compared with the impact energy.Our study suggests a marked increase of extensive damage to different body regions at about 20 kJ and more. The thorax was most often affected, regardless of the amount of impacting energy and the primary impact site. Cranial fracture frequency displayed a biphasic distribution with regard to the impacting energy; they were more frequent in energies of less than 10, and more than 20 kJ, but rarer in the intermediate energy group, namely that of 10–20 kJ.     

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...     

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.     

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.     

多层螺旋CT在交通事故损伤生物力学分析中的应用

目的探讨多层螺旋CT(multi-slice computed tomography,MSCT)及三维重建技术在交通事故损伤生物力学分析方面的应用价值。方法以真实案例为基础,通过MSCT扫描获得尸体断层影像,进行三维图像重建,结合尸体解剖、车辆勘验等结果综合分析交通事故撞击、碾压和挤压等行为方式中的生物力学过程,并与尸体解剖结果进行对比。结果 MSCT和三维重建获得了不同受力部位骨折的位置、骨折线走向以及骨内碎裂状况等原位特征,其对于骨折的精细还原优于尸体解剖。结论 MSCT和三维重建技术在原位特征的再现、图像的易操作性以及证据的保全等方面凸显优势,可对道路交通事故损伤生物力学分析起补充和引导作用。     

The role of mobile computed tomography in mass fatality incidents

Mobile multi-detector computed tomography (MDCT) scanners are potentially available to temporary mortuaries and can be operational within 20 min of arrival. We describe, to our knowledge, the first use of mobile MDCT for a mass fatality incident. A mobile MDCT scanner attended the disaster mortuary after a five vehicle road traffic incident. Five out of six bodies were successfully imaged by MDCT in c. 15 min per body. Subsequent full radiological analysis took c. 1 h per case. The results were compared to the autopsy examinations. We discuss the advantages and disadvantages of imaging with mobile MDCT in relation to mass fatality work, illustrating the body pathway process, and its role in the identification of the pathology, personal effects, and health and safety hazards. We propose that the adoption of a single modality of mobile MDCT could replace the current use of multiple radiological sources within a mass fatality mortuary.     

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.     

螺旋CT三维成像技术在疑难骨外伤中的应用价值

目的探讨螺旋CT(SCT)三维(3D)成像技术在法医疑难骨外伤中的诊断价值。方法选择11例骨外伤病人进行X线及螺旋CT3D检查,观察和分析骨折的位置、数量及性质。结果11例中,X线检查共发现肋骨骨折34处,肩胛骨骨折1处,鼻骨骨折2处,掌骨不完全性骨折1处,左胫、腓骨骨折1处,耻骨骨折1处。CT检查共发现肋骨骨折47处,肩胛骨粉碎性骨折1处,鼻骨骨折明显移位1处,排除骨折1处,上颌骨骨折1处,掌骨完全性骨折1处,左胫、腓骨陈旧性骨折1处,骶骼关节脱位1处,第5腰椎椎弓根骨折1处。结合三维图像,冠位状及矢位状重组图像清晰地显示出骨折线的部位、数量、性质和错位、复原等情况。结论螺旋CT三维成像应用对法医复杂骨外伤的客观诊断非常有效,优于常规X线检查。     

Human coxal bone sexual dimorphism and multislice computed tomography: geometric morphometric analysis of 65 adults

The authors studied sexually dimorphic differences in coxal shape using geometric morphometric analysis of 15 osteometric landmarks recorded by multislice computed tomography (MSCT), based on three-dimensional reconstructions of 65 Caucasian adults. Geometric morphometric analysis, principal component analysis, canonical variates analysis, and other discriminant analysis (Goodall's F-test and Mahalanobis distance) were performed for the three separate bones of the left innominate (pubis, ilium, and ischium), the modified pubis (pubis and ischiopubic ramus), the modified ilium (ilium and ischial spine), three bone complexes (ischiopubic, iliopubic, and ilio-ischial), and the complete innominate. A cross-validation test was also performed. All areas studied were dimorphic, but results for sexual dimorphism in decreasing order were as follows: the modified pubis, followed by the ischiopubic complex, the iliopubic complex and the complete innominate, the pubis, the modified ilium, the ilio-ischial complex, the ilium, and finally the ischium. These results show the potential of this approach for future anthropological research.     

Anthropological measurement of lower limb and foot bones using multi-detector computed tomography

Anthropological examination of defleshed bones is the gold standard for osteological measurement in forensic practice. However, multi-detector computed tomography (MDCT) offers the opportunity of three-dimensional imaging of skeletal elements, allowing measurement of bones in any plane without defleshing. We present our experiences of the examination of 15 human lower limbs in different states of decomposition using MDCT. We present our method of imaging and radiological measurement of the bones including sex assessment. The radiological measurements were undertaken by three professional groups--anthropology, radiology, and forensic pathology--both at the site of scanning and at a remote site. The results were compared to anthropological oestological assessment of the defleshed bones. We discuss the limitations of this technique and the potential applications of our observations. We introduce the concept of remote radiological anthropological measurement of bones, so-called tele-anthro-radiology and the role that this could play in providing the facility for standardization of protocols, international peer review and quality assurance schemes.     

Age estimation and the developing third molar tooth: an analysis of an Australian population using computed tomography

The third molar tooth is one of the few anatomical sites available for age estimation of unknown age individuals in the late adolescent years. Computed tomography (CT) images were assessed in an Australian population aged from 15 to 25 years for development trends, particularly concerning age estimation at the child/adult transition point of 18 years. The CT images were also compared to conventional radiographs to assess the developmental scoring agreement between the two and it was found that agreement of Demirjian scores between the two imaging modalities was excellent. The relatively wide age ranges (mean ± 2SD) indicate that the third molar is not a precise tool for age estimation (age ranges of 3-8 years) but is, however, a useful tool for discriminating the adult/child transition age of 18 years. In the current study 100% of females and 96% of males with completed roots were over 18 years of age.     

运用薄层CT扫描评估四川汉族青年锁骨胸骨端骨骼年龄

目的 运用薄层CT扫描探索四川汉族青年锁骨胸骨端骨骺发育状况及其与生活年龄的关系.方法 结合Schmeling等提出的骨发育分级法,并考虑本研究样本的年龄区间,将锁骨胸骨端骨骺发育分为4个等级.依据上述骨骺发育等级阅读565例15～25周岁青年胸部薄层CT片,并对锁骨胸骨端骨骺发育状况进行统计学描述性研究.结果 两性之...     

Virtual determination of sex: metric and nonmetric traits of the adult pelvis from 3D computed tomography models

Examination of the adult os coxae and sacrum is one of the most common methods of sex estimation from bone. Medical imaging, such as computed tomography (CT), provides the opportunity for three-dimensional (3D) imaging of the skeleton from clinical scans of known individuals in situ. In this study, a randomly selected subset of abdominopelvic CT-derived models were used to evaluate simple, repeatable metric methods of sex estimation based on a combination of obstetric measurements and the traditionally nonmetric Phenice-derived traits. A four-variable discriminant function for sex estimation was developed based on statistical analyses. Overall, the cross-validated accuracy of this method was 100%, with inter-observer error showing an average of only 2.2%. Comparative analysis was run on the data set using FORDISC 3.0. This study shows that current sex determination standards from the pelvis should be updated to include more in vivo data to increase the accuracy of identification.     

Accuracy and reliability of cone beam computed tomography of the jaws for comparative forensic identification: a preliminary study

Conventional computed tomography is an emerging modality in forensic identification but is not sufficiently accurate for use in dental identification primarily because of problems with metallic dental restoration-induced streak artifact. In this study, the accuracy and reliability of recording forensic information from cone beam computed tomography (CBCT) scans of the jaws when compared to conventional panoramic radiographs has been analyzed under experimental conditions. Information could be recorded with near-perfect repeatability and reproducibility. Information could also be recorded accurately, the sensitivity being 96.6% (95% CI, 95.1-98.1) and specificity being 98.4% (95% CI, 96.2-100). The metal dental restoration-induced streak artifact was at a level that permitted, in most cases, accurate observations. This is considered an important step in validating CBCT as a tool in comparative dental identification of bodies. It may have a role in mass fatalities and in chemical, biological, radiological, and nuclear incidents, but further studies are required to assess the feasibility of this.     

Sex estimation in a Turkish population using Purkait’s triangle: a virtual approach by 3-dimensional computed tomography (3D-CT)

Sex estimation is considered one of the first steps in the forensic identification process. Morphological and morphometrical differences between males and females have been used as means for morphoscopic and metric methods on both cranial and postcranial skeletal elements. When dry skeletal elements are not available, virtual data can be used as a substitute. The present research explores 3-dimensional (3D) scans from a Turkish population to test a sex estimation method developed by Purkait (2005).Overall, 296 individuals were used in this study (158 males and 138 females). Purkait’s triangle parameters were measured on computed tomography (CT) scans obtained from both right and left femora of each patient at the Bakirkoy Dr. Sadi Konuk Training Research Hospital (Istanbul, Turkey). Intra- and inter-observer errors were assessed for all variables through technical error of measurements analysis. Bilateral asymmetry and sex differences were evaluated using parametric and non-parametric statistical approaches. Univariate and multivariate discriminant function analyses were then conducted.Observer errors demonstrated an overall agreement within and between experts, as indicated by technical error of measurement (TEM) results. No bilateral asymmetries were reported, and all parameters demonstrated a statistically significant difference between males and females. Fourteen discriminant models were generated by applying single and combined parameters, producing a total correct sex classification ranging from 78.4% to 92.6%. In addition, over 67% of the total sample was accurately classified, with 95% or greater posterior probabilities.Our study demonstrates the feasibility of 3D sex estimation using Purkait’s triangle on a Turkish population, with accuracy rates comparable to those reported in other populations. This is the first attempt to apply this method on virtual data and although further validation and standardisation are recommended for its application on dry bone, this research constitutes a significant contribution to the development of population-specific standards when only virtual data are available.

Key points

• CT analysis using Purkait’s triangle is a suitable tool for assessment of sex in unidentified individuals.
• The best overall estimation rate was achieved with the F11 model, with around 92% of accuracy.
• The results suggested 78.4% to 92.6% correct sex identification rates.
• More research is needed to expand the sample set and verify the results.