多层螺旋CT、普通CT和X线在骨折法医学鉴定中的应用

目的比较多层螺旋CT（MSCT）、普通CT与X线3种检查法,评价它们在骨折法医鉴定中的应用价值。方法对366例受检者（已接受其他影像学检查）行MSCT薄层扫描并行SSD,透明化X线模拟投影和MPR处理。统计分析MSCT、CT常规与X线检查在各部位骨折中的诊断正确率和漏、误诊率并行χ2检验。结果鼻骨、肋骨、四肢及关节、眶骨、颅骨骨折MSCT诊断正确率明显高于普通CT或X线（P〈0.01）。MSCT与普通CT对脊柱骨折的诊断正确率无统计学差异（P〉0.05）。MSCT、普通CT与X线的总体诊断正确率分别为99.45%、70.27%和59.17%。常规CT、X线与MSCT诊断结果间存在显著统计学差异（P〈0.001）。结论MSCT对骨折的显示更准确,可作为法医鉴定的重要辅助检查手段。     

Post-mortem interval estimation based on insect evidence in a quasi-indoor habitat

Insects collected on indoor cadavers are frequently used for post-mortem interval (PMI) estimation. Buildings encountered during crime investigations vary according to temperatures inside, the extent of insect access restriction or sanitary conditions. This article reports the PMI oriented analyses of insect evidence sampled from the human cadaver in the atypical indoor habitat. The body was found in the uninhabited house, on the floor covered with rubbish, in the room with no doors and windows. Thermal conditions in the room were less variable than in the local weather station, however still much more variable compared to the typical indoor habitat, indicating the need for retrospective correction of temperature records from the station. Cadaver entomofauna was surprisingly diverse and abundant. We recorded several taxa usually not occurring on indoor cadavers, e.g. immature stages of Necrodes littoralis (Coleoptera: Silphidae) or Stearibia nigriceps (Diptera: Piophilidae). PMI was based on the age and the pre-appearance interval estimated for live puparium of S. nigriceps, giving the total interval of 37 (±7.4) days plus 4–20?days resulting from the absence of first colonizing specimens of the species. This estimate was corroborated with the age estimate for empty puparia of Sarcophaga argyrostoma (Diptera: Sarcophagidae) with traces of Nasonia sp. (Hymenoptera: Pteromalidae) eclosion. Other insects indicated shorter but consistent PMI. Difficulties and limitations of insect-based PMI estimations in unusual indoor habitats are discussed.     

骨折法医鉴定中常规X线与CT漏诊、误诊的技术因素分析

目的 探讨X线平片和常规CT检查技术对骨折漏、误诊的影响。方法 对366例已接受普通X线或常规CT检查的骨折法医鉴定者行MSCT扫描并行对照性研究。结果 骨折法医鉴定中普通X线、常规CT漏、误诊率分别为40.83%和29.73%，存在显著统计学差异（x^2=4.69，P＜0.05）。二者漏、误诊病例中与技术因素相关者分别占66.29%和88.63%，亦存在显著统计学差异（x^2=7.58，P＜0.01）。结论 普通X线与常规CT的设备和技术缺陷与失误是造成漏、误诊的重要因素。     

骨折法医鉴定中常规X线与CT漏诊、误诊的技术因素分析

目的探讨X线平片和常规CT检查技术对骨折漏、误诊的影响。方法对366例已接受普通X线或常规CT检查的骨折法医鉴定者行MSCT扫描并行对照性研究。结果骨折法医鉴定中普通X线、常规CT漏、误诊率分别为40.83%和29.73%,存在显著统计学差异(x2=4.69,P<0.05)。二者漏、误诊病例中与技术因素相关者分别占66.29%和88.63%,亦存在显著统计学差异(x2=7.58,P<0.01)。结论普通X线与常规CT的设备和技术缺陷与失误是造成漏、误诊的重要因素。     

根据骨盆CT片特征指标进行同一认定的研究

目的选择骨盆CT片上的特征指标,建立逐步回归方程,探讨其在法医学同一认定中的应用价值。方法收集160名不同被检查者骨盆CT影像片各1张,70名被检查者不同次骨盆CT影像片各2张。选择并测量骨盆CT片上的14项指标值,分别计算不同人随机分组相同测量指标的组间的差值,以及相同人不同次测量指标间的差值,运用二分类logistic逐步回归分析,建立各项指标的一元回归方程和多项指标的多元回归方程,并对方程进行盲测检验。结果建立的14个一元方程中同一认定的正确率在61.1%(骶骨耳状面后缘宽)~80.5%(第一骶椎平面左右髂骨前端间距)之间;建立的6个多元回归方程的正确率在80.5%~93.8%之间。盲测准确率为100%。结论本文在CT片上选择的14项特征指标可以用于同一认定,在使用时应尽可能选用多元指标以得到更准确的结果。     

Personal identification based on radiographic vertebral features

Personal identification of human remains constitutes about 10% of the normal caseload of any forensic medicine practice. Identification can be achieved by a variety of methods, one of which is the comparison of antemortem and postmortem radiographs. There are numerous accounts of cranial and dental radiographic features useful for identification, whereas the availability of postcranial radiographs and especially plates that depict the vertebral column is less widespread among the forensic community. The authors here review the various vertebral features instrumental in positive identification that can be identified on radiographs of the spine.     

Sentence identification system based on criminal law ontology

In this research, an identification system is proposed for the benefit of determining a possible sentence and retrieving the related cases under criminal law codes of Thailand. The system is based on the developed criminal law ontology for the advantage of structuralizing and semanticizing in selected articles. From the underlying legal elements described in law codes textually, the ontology shall provide the determination of possible sentences which consist of judgment and theoretically figured range of punishments. An application has been designed and demonstrated in two consequential modules: the legal elements identification and the sentence identification. The developed ontology and its extended web application will be shown and illustrated as a sequential flow and evaluated by the legal experts and the end-users. The evaluation results showed that the averaged satisfactions for both groups of experts and end-users were 89% and 84%, respectively.     

中国汉族成人颅骨CT片同一认定方法的研究

目的建立对中国汉族成人颅骨CT片进行同一认定的方法。方法按照纳入标准收集100例中国汉族成人颅骨CT片，对确定的识别指标进行观察和测量，对各指标的观测结果进行分类编码，然后按观测顺序编制特异的12位颅骨CT片识别编码。运用SPSS13．0统计学软件对所得数据进行各指标年龄和性别差异的统计学分析，利用个人识别能力公式计算单个指标和总体指标的个人识别能力。结果12项识别指标中有6个指标存在男女性别差异；12项指标累计个人识别能力可达到99．9997997％。结论本文确定中国汉族成人颅骨CT片12项观测指标，利用指标分类编码法可进行中国汉族成人颅骨CT片的同一认定。     

Personality identification based on the outcomes of mass casualty events

This study concerns the problem of personality identification based on the outcomes of mass casualty events. New organizational measures are proposed to optimize the work with cadaveric materials. Specifically, they envisage creation of four major working groups and organization of their cooperation along the following lines: collection and delivery of postmortem information, systematization of antemortal information, and functioning of the identification centre. DNA-technologies and computer-assisted data processing are shown to find the increasingly wider application for personality identification.     

Rationale of identification based on biological factors of the dentition

Dental traits in the nature of form and size of fissures, cusps, and pits often reflect genetic and phylogenetic interactions in growth and development that are common to other individuals and serve a useful purpose in identification.     

根据股骨组织形态学变化进行骨骼种属鉴别

目的通过对成年人、成体黄牛、马、家猪、山羊、绵羊、狗、猫、长毛兔、鹅、鸭、鸡共12个种属动物股骨组织形态学结构特征的研究,建立一个有效的各类动物间种属鉴别的方法。方法在征得家属同意后,在尸检中取成人(20岁以上)右股骨中段约4cm,同时,收集黄牛、马、家猪、山羊、绵羊、狗、猫、长毛兔、鹅、鸭、鸡共11种常见动物右腿股骨,取中段约4cm,脱钙后制作成骨组织切片,在光学显微镜下观察,将显微镜下的图像录入电脑,选取24个指标进行分析。结果人与其他动物、以及各被检动物之间在骨单位数量等13个指标上具有显著差异,用这些指标建立种属判别数学模型,结果这些动物之间的判别率也可达89.4%。结论股骨中段骨密质的组织学结构具有明显的种属特征,且骨单位形态和数量呈现明显的生物进化趋势。根据这些特征可以有效地进行种属鉴别。     

Principles of medical and trace examinations in expert evaluation of transport accident traumas based on roentgenological methods

Airtraffic and car traumas illustrate possibilities of x-ray methods in expert examination of transport trauma. X-ray data is most important in clarification of traumatic mechanisms and defects on the clothes of the victims which point to the accident details. Further accumulation of the material will allow introduction of more precise assays of the signs assessment.     

CT在肋骨骨折认定中的价值及骨折的力学分析

目的探讨在法医学鉴定中普通X线片难以确定的肋骨骨折,以CT技术加以显示的方法,并阐明肋骨骨折的力学原理。方法对17例普通X线技术显示困难的肋骨骨折行CT扫描,采用薄层平滑和高分辨率重建、表面遮盖法和多平面重建观察,确定肋骨骨折的部位、数量、形态、移位和骨痂形成情况等信息。结果17例X线平片难以确定的骨折,通过上述CT扫描和后处理重建技术,均得到满意的结果。通过骨折力学分析和影像观察,将间接暴力导致肋骨骨折的力矩分成垂直和旋转两类,从而提出垂直型和旋转型肋骨骨折的分类。结论对普通X线平片难以确定的肋骨骨折,建议采用薄层CT扫描,沿肋骨长轴多平面重建观察,结合肋骨骨折的力学原理,有助于避免将急性旋转型肋骨骨折误诊为陈旧骨折。     

法学视角下过度医疗行为的认定

《侵权责任法》在法律的层面对过度检查行为做出了禁止性规定,但是司法实践中过度医疗行为的认定仍旧是一个难题。本文在对过度医疗概念进行法律界定的基础上,提出了过度医疗的认定标准,并结合新修改的《民事诉讼法》,探讨了过度医疗认定中的鉴定制度、专家辅助人制度等问题。     

A Bayesian approach based on Kalman filter frameworks for bullet identification

When a bullet is fired from a barrel, random imperfections in the interior surface of the barrel imprint 3-D micro structures on the bullet surface that are seen as striations. Despite being random and non-stationary in nature, these striations are known to be consistently reproduced in a unique pattern on every bullet. This is a key idea in bullet identification. Common procedures in the field of automatic bullet identification include extraction of a feature profile from bullet image, profile smoothing and comparison of profiles using normalized cross correlation. Since the cross correlation based comparison is susceptible to high-frequency noise and nonlinear baseline drift, profile smoothing is a critical step in bullet identification. In previous work, we considered bullet images as nonlinear non-stationary processes and applied ensemble empirical mode decomposition (EEMD) as a preprocessing algorithm for smoothing and feature extraction. Using EEMD, each bullet average profile was decomposed into several scales known as intrinsic mode functions (IMFs). By choosing an appropriate range of scales, the resultant smoothed profile contained less high-frequency noise and no nonlinear baseline drift. But the procedure of choosing the proper number of IMFs to reduce the high-frequency noise effect was manual. This poses a problem in comparison of bullets whose images contained less or more noise in comparison to others because their useful information may be present in the corresponding discarded IMFs. Moreover, another problem arises when the bullet type changes. In this case manual inspection is needed once more to figure out which range of IMFs contain less high-frequency noise for this particular type of bullet. In this paper, we propose a novel combination of EEMD and Bayesian Kalman filter to solve these problems. First the bullet images are rotated using Radon transform. The rotated images are averaged column-wise to acquire averaged 1-D profiles. The nonlinear baseline drifts of averaged profiles are removed using EEMD algorithm. The profiles are then processed by a Kalman filter that is designed to automatically and optimally reduce the effect of high-frequency noise. Using Expectation Maximization (EM) technique, for each averaged profile, the parameters of Kalman filter are reconfigured to optimally suppress the high-frequency noise in each averaged profile. This work is the first effort that practically implements the Kalman filter for optimal denoising of firearm image profiles. In addition, we believe that Euclidean distance metric can help the normalized cross-correlation based comparison. Therefore, in this paper, we propose a comparison metric that is invariant to start and endpoints of firearm image profiles. This metric combines the prized properties of both Euclidean and normalized cross-correlation metrics in order to improve identification results. The proposed algorithm was evaluated on a database containing 180 2-D gray-scale images acquired from bullets fired from different AK-47 assault rifles. Although the proposed method needs more calculations in comparison to conventional methods, the experiments showed that it attained better results compared with the conventional methods and the previous method based on EMD in the field of automatic bullet identification.     

CT、MRI在弥漫性轴索损伤法医学鉴定中应用价值分析

目的探讨CT和MRI检查方法在弥漫性轴索损伤(diffuse axonal injury,DAI)法医学鉴定中的应用价值。方法收集26例CT和MRI影像资料齐全的DAI鉴定资料进行回顾性分析,比较CT和MRI两种方法对DAI病灶检出率的差异,分析DAI病灶检出数量与法医学鉴定结果之间的关系。结果 26例经MRI检出DAI病灶787个,经CT检出DAI病灶32个,MRI对DAI病灶的敏感度显著高于CT(P0.01)具有统计学意义。26例DAI鉴定的伤残等级数值与影像学检查发现的病灶数量之间存在负相关(r=-0.908,P0.01)。结论 MRI检查对DAI病灶的检出率较CT检查具有明显优势,可为DAI诊断提供更为准确的依据,在法医临床学鉴定中具有重要的应用价值。     

Discrimination of transparent polyethylene films based on identification of inorganic antiblocking agents

Several nondestructive and semidestructive analyses were used to discriminate colorless transparent polyethylene bags. Transparent plastic bags made from low-density and linear low-density polyethylene usually contain antiblocking agents to prevent sticking of the film, which makes it difficult to open the mouths of plastic bags. Inorganic antiblocking agents are uniformly dispersed in polyethylene films, so they are easily observed using optical microscopy. The particle size distributions of the antiblocking agents were compared by statistical tests. Particle composition was examined by elemental analysis using energy-dispersive X-ray spectrometry with a scanning electron microscope and by molecular vibration analysis using a sensitive microscopic Raman spectrometer. The compositions could be determined nondestructively on the basis of the results. These data reinforce the morphological discrimination. Morphological discrimination of the dispersed antiblocking agent powders, statistical comparison of particle size distributions, and compositional analysis of the antiblocking agents strengthen the ability to discriminate polyethylene films.