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.     

Age estimation using radiographic analysis of laryngeal cartilage

The laryngeal cartilages undergo age changes, including mineralization and ossification. Keen and Wainwright defined, in male and female subjects, recognizable stages of radiopacity of the thyroid, cricoid, and arytenoid cartilages. The present study analyzed quantitatively the degree of laryngeal radiopacity to determine whether radiography of the larynx can be used routinely in forensic pathology to estimate age at death. In each of 82 subjects, the larynx was removed during forensic autopsy and subjected to radiography in an anteroposterior orientation. Each radiograph was independently scored by two observers. For each case, the degree of laryngeal radiopacity was evaluated according to the classification of Keen and Wainwright. There was a positive correlation between the total score of laryngeal radiopacity and age (correlation coefficient = 0.74). It was concluded that this method is simple, fast, and nondestructive and has a good reproducibility between observers. Because there was a wide interindividual variability in the same age class, this method must be associated with more accurate methods.     

基于数据挖掘实现成人喉软骨和舌骨CT图像重组的年龄推断

目的 运用数据挖掘技术探索喉软骨和舌骨CT图像重组用于成人年龄推断的可行性.方法 收集413例颈部薄层CT图像,样本年龄范围18～<80岁,将样本随机分为测试集和训练集.参照TURK等的分级方法,对所有样本进行全方位综合阅片分级,将甲状软骨骨化过程分为6级,环状软骨骨化过程分为5级,舌骨大角和舌骨体的骨性结合分为3级....     

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.     

成像技术用于锁骨年龄推断的研究进展

锁骨内侧端和肩峰端随年龄变化具有一定规律性,尤其是内侧端骨骺愈合程度,对于30岁以下的年龄推断具有重要价值。国内外法医人类学家对锁骨大体解剖及影像特点进行了大量研究,积累了丰富的科研和应用基础。CT和MRI等影像新技术的应用将有望提高锁骨年龄推断的准确性。     

Estimation of Age Using Alveolar Bone Loss: Forensic and Anthropological Applications

The objective of this study was to utilize a new odontological methodological approach based on radiographic for age estimation. The study was comprised of 397 participants aged between 9 and 87 years. A clinical examination and a radiographic assessment of alveolar bone loss were performed. Direct measures of alveolar bone level were recorded using CT scans. A medical examination report was attached to the investigation file. Because of the link between alveolar bone loss and age, a model was proposed to enable simple, reliable, and quick age estimation. This work added new arguments for age estimation. This study aimed to develop a simple, standardized, and reproducible technique for age estimation of adults of actual populations in forensic medicine and ancient populations in funeral anthropology.     

Study of Chilean Children’s Dental Maturation*

Abstract: In forensic science, determining a person’s chronological age has become a challenge for researchers. Determining age using dental calcification is becoming increasingly important. The objective of this study is to estimate the dental age of the children’s population in Region VIII, Chile. The sample was randomly taken from children under the care of the Faculty of Dentistry at the Universidad de Concepción in Chile. The study encompasses 159 children between 3 and 14 years of age. The dental age was determined following the Demirjian method. The Bland–Altman method was applied to establish the correlation. It was determined that the range between chronological and dental age is similar, and the degree of correlation between both ages is nearly perfect. In conclusion, the degree of correlation between the chronological and dental ages for each gender is also very good although it is slightly higher for females.     

Testing the Demirjian and the international Demirjian dental aging methods on a mixed ancestry urban American subadult sample from Detroit, MI

This paper tests the Demirjian and international Demirjian dental aging methods for forensic use when ancestry and ethnicity are unknown. A radiographic sample of 187 boys and girls was collected from the Department of Pediatric Dentistry at the University of Detroit Mercy and aged using both methods. The total sample and the sample by age categories (young, middle, and old) were analyzed using t-tests. The Demirjian method was found to better estimate age to a statistically significant degree for the total sample, as well as the middle and old age categories. The young category was aged better using the international Demirjian method. The results indicate that while the Demirjian method accurately estimates age, caution must be used with the method. Further research is needed to determine whether the international Demirjian method can be used for forensics in the U.S.     

A Comparison of Coronary Artery Stenosis Estimates Made by Forensic Pathologists and Medical Students

Previous studies suggest cardiovascular pathologists are less accurate than noncardiovascular pathologists (e.g., clinical pathologists) in estimating the degree of coronary artery stenosis. To further investigate the effect of training on accurate estimation of coronary artery stenosis, we designed a study to compare the accuracy of estimates made by forensic pathologists versus medical students. Six forensic pathologists and twelve medical students each independently examined 24 images of coronary artery cross sections and gave an estimate of the degree of stenosis. When comparing all 24 images, the forensic pathologists had a median difference between the estimated percentage of stenosis and actual percentage of stenosis of −12.380 and the medical students had a median difference of −16.50 (p-value of 0.08542). In estimating the percentage of stenosis, training in forensic pathology does not guarantee significantly improved accuracy compared with medical students. Our study showed no consistent statistically significant difference between estimates given by forensic pathologists and by medical students.     

Recommended Practices for Macerating Human Thyroid Cartilage

Visible abnormalities on the thyroid cartilage may be indicative of perimortem trauma including fractures or sharp force trauma. During autopsy, the thyroid cartilage must be freed of surrounding soft tissue before these abnormalities can be clearly observed. Several processing methods were first experimentally tested on pig ears to narrow down which might work best to process human thyroid cartilage. Several methods in the categories of hot water maceration, chemical/enzyme maceration, and dermestid beetles were then tested on a sample of 37 human thyroid cartilages. An adapted 22-point scoring system was used to score the efficacy of each processing method. Chemical maceration using bleach was found to be the best method for removing surrounding tissue from thyroid cartilage, with Arm & Hammer^TM powdered laundry detergent as a close second. These methods are inexpensive, quick, and easy to implement, making them a simple addition to busy medical examiner’s offices or forensic anthropology laboratories.     

Accuracy of BR Regression Equation for Impacted Teeth in Age Estimation in Haryana Population of India

Abstract:  Dental cementum is a vital tissue that demonstrates continuous apposition throughout the life of a tooth. Positive correlation has been reported between the coronal displacement of cementum and age in impacted teeth and BR regression equation has been proposed. The present study is an attempt to calculate accuracy of BR regression equation in Haryana population of India. The study was conducted on 20 impacted mandibular third molars extracted from healthy patients, aged between 22 and 32 years. The bucco-lingual ground sections were prepared and the distance between the edges of enamel and cementum were measured with micrometer attached to a light microscope and BR regression equation was applied for age estimation. Although the estimated age with BR regression equation was less than chronological age it was not statistically significant. Hence, the BR regression equation can be used in medicolegal as well as in forensic odontology for age estimation.     

Radiographic Recognition of Dental Implants as an Aid to Identifying the Deceased

Abstract:  This study was undertaken to determine if dental implants can be radiographically differentiated by company type to aid forensic identification of the deceased. Recognition of dental implants on intraoral radiographic images was assessed in a blind study using a radiographic examination guide to highlight differences between dental implants. Inter- and intra-examiner comparisons were conducted and a computer program (Implant Recognition System^®) was evaluated to see whether it improved the accuracy of implant recognition. The study found that dental implants could be radiographically differentiated by company type. The Implant Recognition System^® in its current form was of little benefit for radiographic assessment of dental implants for forensic odontologists. Prior knowledge of implant types, with a McNemar's statistical value of 92.9, proved to be most significant in identification.     

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...     

Child abduction murder: the impact of forensic evidence on solvability

This study examined 733 child abduction murders (CAMs) occurring from 1968 to 2002 to explore the influence of forensic evidence on case solvability in CAM investigations. It was hypothesized that the presence of forensic evidence connecting the offender to the crime would enhance case solvability in murder investigations of abducted children. This study examined the impact of CAM of different types of forensic evidence and the impact of the summed total of forensic evidence items on case solvability by controlling for victim age, victim race, victim gender, and victim-offender relationship. Time and distance theoretical predictors were also included. Binomial logistic regression models were used to determine whether forensic evidence was a critical solvability factor in murder investigations of abducted children. This research indicated that, while forensic evidence increased case solvability, the impact of forensic evidence on solvability was not as important as other solvability factors examined.     

A Radiographic Study on the Utility of Cranial Vault Outlines for Positive Identifications

A standard method for positive identification is the use of antemortem and postmortem radiographic comparisons. The purpose of this research is to test the visual accuracy of antemortem and postmortem radiographic comparisons of cranial vault outlines and to evaluate their uniqueness using geometric morphometric methods. A sample of 106 individuals with varying levels of education and forensic case experience participated in a visual accuracy test. Of the 106 individuals, only 42% correctly assigned all of the radiographs, with accuracy rates ranging from 70 to 93% for each radiographic comparison. Vault shape was further examined using elliptic Fourier analysis, and paired t‐tests were computed on the first 10 principal components accounting for 100% of the variance, which found no significant differences. The visual accuracy test and elliptic Fourier analysis shows that vault outlines may not be unique enough for positive identifications when used as a sole indicator.     

根据中国汉族男性甲状软骨推算年龄的研究

目的根据中国汉族男性甲状软骨推算年龄。方法对73例已知年龄的中国汉族男性甲状软骨进行软X线摄片和(或)X线摄片,从摄片上选择8个与年龄变化关系较为密切的观察部位,每个部位又划分成3至6个等级,然后采用多元线性回归方法,建立其推算年龄的数学模型。结果运用该方法推算男性甲状软骨年龄,其标准差为1.354,复相关系数R为0.9971。结论本方法适用于中国汉族男性甲状软骨的年龄推算,其有效力年龄范围为13-67岁。     

Digital behavioral-fingerprint for user attribution in digital forensics: Are we there yet?

the need for a reliable and complementary identifier mechanism in a digital forensic analysis is the focus of this study. Mouse dynamics have been applied in information security studies, particularly, continuous authentication and authorization. However, the method applied in security is void of specific behavioral signature of a user, which inhibits its applicability in digital forensic science. This study investigated the likelihood of the observation of a unique signature from mouse dynamics of a computer user. An initial mouse path model was developed using non-finite automata. Thereafter, a set-theory based adaptive two-stage hash function and a multi-stage rule-based semantic algorithm were developed to observe the feasibility of a unique signature for forensic usage. An experimental process which comprises three existing mouse dynamics datasets were used to evaluate the applicability of the developed mechanism. The result showed a low likelihood of extracting unique behavioral signature which can be used in a user attribution process. Whilst digital forensic readiness mechanism could be a potential approach that can be used to achieve a reliable behavioral biometrics modality, the lack of unique signature presents a limitation. In addition, the result supports the logic that the current state of behavioral biometric modality, particularly mouse dynamics, is not suitable for forensic usage. Hence, the study concluded that whilst mouse dynamics-based behavioral biometrics may be a complementary modality in security studies, more will be required to adopt it as a forensic modality in litigation. Furthermore, the result from this study finds relevance in other human attributional studies such as user identification in recommender systems, e-commerce, and online profiling systems, where the degree of accuracy is not relatively high.     

Use of radiographic atlases in a mass fatality

In May and June of 1996, a forensic anthropology team from the C.A. Pound Human Identification Laboratory at the University of Florida identified 9 of 10 juveniles from the crash of ValuJet 592. The team relied primarily on a radiographic atlas developed and used by clinical practitioners to determine skeletal age. Postmortem radiographs of the juvenile victims were compared with radiographic standards to determine skeletal age. Skeletal age was then compared to a passenger list indicating the sex, weight, height, and chronological age of each individual. Tentative identifications based on the atlas method were organized into an exclusion matrix. Final identifications were based on this assessment in conjunction with other anthropological data such as appearance and fusion of ossification centers and estimation of stature.     

A Test of Sex Estimation in Subadults Using the Elevation of the Auricular Surface from Four Samples of Known Age and Sex

Biological sex is foundational to the work of forensic anthropologists and bioarcheologists. The lack of reliable biological sex estimation methods for subadults has, thus, greatly limited forensic and bioarcheological analyses. Auricular surface elevation showed promise as a subadult sex estimation method in previous studies. This study examined two auricular surface elevation evaluation methods on four subadult samples of known age, sex, and ancestry. Samples were scored as “male,” “female,” or “indeterminate” and results were examined with chi‐square analysis. No consistent sex estimation pattern, accuracy, or predictive value was produced between samples. Only one test was significant using Fisher's exact test analysis (FET = 7.501, p < 0.022): the composite approach on the Hamann‐Todd sample. While age, sample size, or developmental factors may play a role in these results, clearly sample variation does as well. This study found auricular surface elevation was not a useful subadult sex estimation method.