锁骨胸骨端薄层CT扫描并图像重组的骨骺发育分级方法

目的运用薄层CT扫描并多平面重组(multiplanar reconstruction,MPR)及容积再现(volume reconstruction,VR)技术探讨青少年锁骨胸骨端骨骺发育CT分级方法。方法通过薄层CT冠状面、横断面扫描以及MPR、VR技术观察我国华东、华南地区460名15～25周岁男、女性青少年双侧锁骨胸骨端发育影像特征,测量并计算双侧锁骨胸骨端骨骺最长径、干骺端最长径、骨骺最长径与干骺端最长径比值、骨骺面积、干骺端面积以及骨骺面积与干骺端面积比值,建立锁骨胸骨端骨骺发育CT分级方法。结果在Schmeling分级的基础上,融合锁骨胸骨端CT图像重组信息,将锁骨胸骨端骨骺发育过程分为1～5级,其中2级和3级分别包括a、b、c 3个亚级。结论应用于本分级的样本量大、年龄范围宽、可操作性强,利用CT图像重组技术,分析与青少年锁骨胸骨端骨骺发育密切相关的数据,增加了本分级方法的可行性。     

舌骨形态特征及其性别差异

目的了解舌骨的形态特征,分析其性别差异以及法医学意义。方法收集成人尸体的舌骨68例,加温后除去多余的软组织,肉眼观察舌骨体与舌骨大、小角连接的性质,形态特征及其骨化程度,测量舌骨体高和舌骨体弓高,并比较两者在男、女两性间差异,推导舌骨性别的判别分析方程。结果获得了双侧完全骨化、双侧无骨化、双侧部分骨化、单侧完全骨化(另一侧部分骨化)、单侧完全骨化(另一侧无骨化)5种骨化连接状态,且男性舌骨弓高(x1)和舌骨体高(x2)均大于女性(P0.01),舌骨性别(y)的最佳判别分析方程:y=0.438x1+1.042 x2-12.979,判别值为-0.272 5,判别率为88.2%。结论根据舌骨的形态性别特征,可为法医鉴定实践提供帮助。     

骨骼CT三维重建图像性别判定和年龄推断研究

目的通过计算骨骼计算机断层扫描(Computed Tomography,CT)三维重建图像判定性别和推断年龄的准确率,评价利用骨骼CT三维重建图像判定性别和推断年龄的可行性。方法将法医人类学教材中性别判定和年龄推断的方法应用于539例骨骼CT三维重建图像样本,判定245例骨盆的性别,推断100例男性耻骨联合、100例男性胸骨和94例男性锁骨的年龄,计算准确率。结果骨盆性别判定准确率为98.4%,耻骨下角和坐骨大切迹是区分性别最好的两项指标。男性耻骨联合、胸骨、锁骨的年龄推断准确率在45%以上,其中锁骨双侧方程准确率最高为77%。结论利用骨骼CT三维重建图像判定性别和推断年龄具有可行性。使用大体标本建立的骨盆形态学性别判定方法可直接应用于骨骼CT三维重建图像。使用大体标本建立的男性耻骨联合、胸骨、锁骨形态学年龄推断指标、分级和评分标准以及方程需要修改和补充。     

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...     

基于机器学习和锁骨胸骨端薄层CT的年龄推断研究

目的 采用Kellinghaus分级法对锁骨胸骨端薄层CT进行人工阅片分级,运用多种传统统计学方法以及机器学习方法构建青少年及成人早期年龄推断模型,探索机器学习技术在四川汉族人群年龄推断研究中的应用价值。方法 回顾性收集491例10～30岁个体的胸部薄层CT影像,参照Kellinghaus分级法对所收集样本进行阅片分级赋分。随机选取10%的数据作为测试集,其余数据作为训练集,综合构建多种青少年及成人早期年龄推断的传统统计学回归模型与机器学习模型,采用平均绝对误差值（Mean Absolute Error,MAE）对模型的性能进行评估。结果统计回归模型中效能最好的模型为三次回归模型,男性MAE值为1.34,女性MAE值为1.57;三种机器学习模型中,随机森林模型对男性的预测效能最好,MAE值为1.39;支持向量模型对女性的预测效能最好,MAE值为1.51。结论在锁骨胸骨端年龄推断模型的构建中,机器学习模型在年龄推断中的准确性有一定提升,但与传统统计学回归模型相比并无明显优势,机器学习方法在锁骨胸骨端年龄推断中的应用价值仍有待进一步探索研究。     

基于深度学习实现肋软骨CT图像自动化骨龄推断

目的 利用深度学习方法对第1～7对成人肋软骨CT重建图像进行特征提取,实现成人肋软骨骨龄的自动化推断。方法 回顾性收集年龄在20岁～70岁之间的男性和女性样本各625例,并通过容积再现技术（VRT）得到对应的VRT图像。通过图像预处理和数据增强之后,将其中的500例作为训练集,125例作为测试集,运用5折交叉验证的方法分别评估Res Net、Res Ne Xt、Dense Net及Google Net网络模型的性能,并将5折交叉验证结果的平均值作为最终推断结果。结果 Res Net50网络模型在男性和女性数据集中都取得了最佳实验结果,平均绝对误差分别为4.56岁和3.91岁,±5.0岁范围内预测准确率分别达到64.00%和70.88%,±10.0岁范围内预测准确率分别达到88.96%和94.40%。结论 与传统方法和机器学习方法相比,深度学习方法能够避免人为因素的影响,并且大大提高了成人肋软骨骨龄推断的准确率、降低了预测年龄与真实年龄之间的平均绝对误差,具有较高的临床应用价值。     

CT技术在骨骼年龄推断研究中应用的进展

法医人类学应用诸多学科的研究方法和先进技术,对个体骨骼识别进行广泛的研究.年龄推断是法医人类学领域中一项重要的研究课题.随着影像学技术的迅速发展,法医人类学家开展了将计算机断层扫描(CT)技术应用于法医人类学领域的研究.CT具有连续快速扫描的成像能力以及强大的图像后处理功能,能够提供多种模式的高分辨骨骼重组图像,对于活体和遗骸的法医人类学鉴定都具有重要意义.本文将综述近年来CT在骨骼年龄推断研究中应用的进展.     

锁骨胸骨端CT扫描的法医学年龄推断

目的运用薄层胸部CT图像,观察锁骨胸骨端继发骨化中心随年龄增长的时序性变化,推测我国北方地区汉族青少年锁骨内侧骨骺发育程度在年龄增长过程中的分布特点。方法评估1369例11~27周岁的北方汉族青少年锁骨胸骨端二次骨化中心的发育情况,并将其进行分期。结果在所观察的数据中锁骨内侧骨化中心最早出现的年龄是12岁,开始融合的最小年龄是15岁,达到完全融合的最小年龄是19岁。在所有分期中,发展到Ⅱa和Ⅱb期时,两性间锁骨内侧骨化中心发育程度有差异,女性发育要早于男性。结论作为最晚愈合的骨化中心,锁骨内侧骨化中心对于法医学年龄的推断有重要的提示作用。     

四川汉族青少年骨盆X线骨龄评估

目的应用骨盆髂嵴与坐骨结节骨骺发育状况的X线影像学特征评估四川汉族青少年的生活年龄。方法参照TW2分级原则,结合本次研究选取的年龄跨度、骨骺发育规律,将髂嵴骨骺发育程度分为8级(0~7级),坐骨结节的骨骺发育程度分为7级(0~6级)。再根据上述分级,对691例四川汉族16~20周岁青少年骨盆X线片进行阅片,运用SPSS 19.0软件进行统计学分析,并将年龄(Y)与髂嵴(X1)、坐骨结节(X2)骨骺发育级别作多元线性回归方程。结果双侧髂嵴、坐骨结节骨骺发育差异无统计学意义(P0.05),髂嵴、坐骨结节骨骺发育在两性之间差异亦无统计学意义(P0.05)。多元回归方程为Y=15.269+0.444 X1+0.236 X2,样本回代检验表明该方程准确性较高。结论通过髂嵴、坐骨结节骨骺发育程度的多元回归方程进行骨龄评估,可以为四川汉族人口进行18周岁的年龄评估提供科学依据。     

1例舌骨骨折的法医学鉴定

1　案例资料王某、男、 40岁。于 2 0 0 2年 3月 2 0日 ,因纠纷被他人用手扼压颈部 ,自诉被扼压有 5～ 6min ,后失去知觉。清醒后感头晕、咽部疼痛 ,以吞咽时为著 ,即入院治疗。入院后CT检查示舌骨骨折。 3月 2 4日法医检验 ,仍诉咽部疼痛。查 :双眼结合膜有充血 ,舌尖处有两处粘膜出血 ,咽后壁粘膜充血。左侧舌骨大角处触痛明显。CT复查 :舌骨于左侧舌骨大角处骨折 (照片 )。2　讨　论舌骨骨折在法医临床学鉴定中是一种不常见的骨折。舌骨位于颌下深处 ,借舌骨上下肌群和颌舌骨肌等所固定。前面体部覆有皮肤和颈阔肌 ,两侧支远端与第三颈…     

Ossification of laryngeal structures as indicators of age

As the role of forensic anthropologists expands to the medical examiner setting, their expertise is being applied beyond the traditional dry skeletal material. In such scenarios radiographic techniques can be applied when maceration is not appropriate. This study explores the use of radiographic analysis of laryngeal structures for age-at-death determination. Isolated human laryngeal structures (n = 104) from individuals between the ages of 15 and 89 were removed at autopsy and radiographically examined. The cricoid and individual regions of the thyroid cartilage were scored according to degree of ossification, and the relationship between age and degree of ossification statistically examined. A previously published study on age-determination from thyroid ossification by Cerny was assessed for accuracy. The results of the study indicate that although a consistent sequence in the ossification of laryngeal structures exists, variations in timing does not permit narrow age range estimates. Consequently the method presented by Cerny is inaccurate and should not be used in the forensic setting.     

Thyroid Cartilage Ossification and Multislice Computed Tomography Examination: A Useful Tool for Age Assessment?

Abstract: Many authors have studied the thyroid cartilage ossification process using radiographic features for age estimation of individuals. Their results were various: Sugiyama reported excellent correlation coefficients between ossification rates and civil age, unlike most other authors. We hypothesized that recent advances in imaging techniques would enable more precise evaluation of the ossification of the thyroid cartilage. We retrospectively analyzed the CT scans of 312 French patients using postprocessing software to examine the pattern of thyroid cartilage ossification, calculating the ossified volume of the cartilage on 3D reconstructions. Pearson’s correlation coefficients for volume were 0.73 for men and 0.75 for women (standard error 18.02 and 17.06), indicating considerable inter‐individual variability. Although a correlation between civil age and morphological changes was found, these methods based on thyroid cartilage ossification were not accurate enough for the assessment of individual age.     

Forensic age estimation on digital X-ray images: Medial epiphyses of the clavicle and first rib ossification in relation to chronological age

In recent years, there has been a renewed interest in forensic sciences about forensic age estimation in living subjects by means of radiological methods. This research was conducted on digital thorax X-rays to test the usefulness of some radiological changes in the clavicle and first rib. The sample consisted in a total of 123 subjects of Spanish origin (61 men and 62 women; age range: 5-75 years). From all subjects, a thorax posterior-anterior radiograph was obtained in digital format. Scoring for fusion of medial epiphyses of the clavicle was carried out by Schmeling's system and ossification of the costal cartilage of the first rib by Michelson's system. Degree of ossification and epiphyseal fusion were analyzed in relation with known age and sex of these subjects. The results give a minimum age of >20 years for full fusion of the medial epiphysis of the clavicle (Stages 4 and 5). Concerning the first rib, all subjects with the final Stage 3 of ossification were above 25 years of age. These results suggest that the first rib ossification might become an additional method to the ones so far recommended for forensic age estimation in subjects around 21. New research would be desirable to confirm this suggestion.     

Forensic Age Estimation Using Thin‐Slice Multidetector CT of the Clavicular Epiphyses Among Adolescent Western Chinese

Reaching the age of 18 years is the most significant step for criminal proceedings in China. In this study, a population of 752 individuals was recruited to clarify how strong the chronological age relates to clavicular ossification status revealed by CT scans with 1 mm slice thickness in the West China Han population. Finally, the epiphysis was observed to commence fusion in females at 16.28 years and 16.74 years in males and be fully ossified by 25.97 years in females and 25.81 years in males. These findings suggested that ossification of medial clavicular epiphyseal cartilage can be used in age estimation for West China Han population with the age threshold of 18 years. By comparison with previous German studies, our results suggested that the pace of ossification of medial clavicular epiphyseal cartilage may be potentially affected by socioeconomic status.     

An Analysis of Hounsfield Unit Values and Volumetrics from Computerized Tomography of the Proximal Femur for Sex and Age Estimation

Sex and age are two elements in the establishment of a biological profile for forensic identification. While the pelvic bones are the most ideal structures for sex estimation, the condition of a body is not always ideal due to the nature of death, such as in mass disasters, or postmortem processes. This study utilized CT scans and resultant 3D models of 100 male and 100 female adults of known ages ranging from 18 to 98 years old to collect volumetric and Hounsfield unit measurements of the proximal femur. Equations were created to establish logistic regression models for sex estimation and linear regression models for age estimation. The resultant sex estimation method had an accuracy of 93.5% and utilized the volume of the proximal femur. This study provides three linear regression models for age with an accuracy range of 86%–92% ±12 years. As imaging technologies are increasingly adopted for forensic purposes, the power of 3D data will provide the opportunity for more quantitative and reproducible analyses. The proposed method for sex and age estimation provides a reliable tool that can be utilized in both day-to-day casework and disaster victim identification.     

Age estimation of Korean adults by occlusal tooth wear

The aim of the present study was to evaluate the validity of the modified Kim's scoring system as a practical method of recording occlusal tooth wear and estimating age. For this purpose, 1092 pairs of maxillary and mandibular full-arch casts were randomly selected, scored, and analyzed. The results showed that the modified Kim's scoring system had excellent reliability, and that occlusal tooth wear had a positive correlation with age. Tooth wear scores of all teeth except the two lower central incisors were higher in males than in females. Calculating tables for age estimation were designed by multiple linear regression analysis. Estimated ages were within +/-5 years of actual ages in 63.5% of male subjects, and 64.0% of female subjects. The accuracy of age estimation was increased when the subjects were divided into two age groups and data were re-analyzed. Collectively, it was shown that the modified Kim's scoring system is a reliable and accurate method for age estimation, and that the data from these 1092 individuals can be used as a standard for age estimation of Korean adults.     

利用中国汉族成年人胸部正位CR片影像学特征判定年龄

目的建立利用胸部正位CR片影像学变化判定年龄的方程,并评价其法医学意义。方法收集381例汉族成年人胸部正位CR片样本,其中男性208例,女性173例。选取胸部右侧第一肋胸骨端、左侧第一肋胸骨端、右侧第五肋胸骨端、左侧锁骨骨小梁和左侧锁骨松质骨网眼5项特征性指标,对351例样本进行描述评分,运用SPSS 19.0软件进行多元线性回归模型条件的基本论证,建立回归方程。并使用30例样本对方程的准确性进行盲测。结果本文所选取的5项胸部正位CR片特征性指标与年龄的关系可以使用线性回归模型(P0.05);建立了1组全指标回归方程和2组分组逐步回归方程,全指标回归方程估计值的标准误男性和女性分别为2.83岁和3.41岁,低年龄组(18~35岁)男性和女性分别为2.47岁和2.79岁,高年龄组(36~50岁)男性和女性分别为2.39岁和2.55岁;随机选取30例样本的盲测结果,误差在3岁以内的,全指标回归方程男性和女性分别为80.0%和73.3%,分组回归方程男性和女性分别为86.7%和80.0%。结论利用胸部正位CR片影像学特征变化可判定年龄。     

基于腰椎高度X线测量技术推断四川汉族女性身高

目的通过腰椎高度X线测量技术,建立四川汉族女性身高的数学模型,为法医人类学研究积累基础数据。方法收集206例四川汉族女性个体按年龄分为A、B、C 3组,其中A组(206例)不分年龄,B组(116例)为20~45岁,C组(90例)为45岁以上,并应用计算机X线摄影(computer radiography,CR)技术分别测量所有样本腰椎CR片中5个椎体(L1~L5)前缘、后缘、中央高度(x1~x15),脊柱腰段中央总长度(x16),同时测量每个个体真实身高,对各测量指标联合与身高的相关性进行线性回归分析,建立推断身高的数学模型,并重新选取62例样本代入数学模型,检验模型的准确性。结果所建立的数学模型经线性回归模型假设检验,均具有统计学意义(P0.05),回归方程的推断标准误为2.982~5.004cm,相关系数为0.370~0.779,复相关系数为0.533~0.834。对每组相关系数、复相关系数最高的方程进行回代检验,其中A组的y=100.33+1.489 x3-0.548 x6+0.772 x9+0.058 x12+0.645 x15的准确率最高,为80.6%(±1SE)、100%(±2SE)。结论本研究建立的数学模型适用于推断四川汉族女性身高。     

Introducing Computed Tomography Standards for Age Estimation of Modern Australian Subadults Using Postnatal Ossification Timings of Select Cranial and Cervical Sites,

Contemporary, population‐specific ossification timings of the cranium are lacking in current literature due to challenges in obtaining large repositories of documented subadult material, forcing Australian practitioners to rely on North American, arguably antiquated reference standards for age estimation. This study assessed the temporal pattern of ossification of the cranium and provides recalibrated probabilistic information for age estimation of modern Australian children. Fusion status of the occipital and frontal bones, atlas, and axis was scored using a modified two‐ to four‐tier system from cranial/cervical DICOM datasets of 585 children aged birth to 10 years. Transition analysis was applied to elucidate maximum‐likelihood estimates between consecutive fusion stages, in conjunction with Bayesian statistics to calculate credible intervals for age estimation. Results demonstrate significant sex differences in skeletal maturation (p < 0.05) and earlier timings in comparison with major literary sources, underscoring the requisite of updated standards for age estimation of modern individuals.