Forensic age diagnostics by magnetic resonance imaging of the proximal humeral epiphysis

Bone age assessment based on different MRI modalities of the proximal humerus epiphysis: the comparisons of T1WI, T2WI, and PDWI

Bone age assessment (BAA) is crucial in various fields, including legal proceedings, athletic competitions, and clinical medicine. However, the use of X-ray methods for age estimation without medical indication is subject to ethical debate, especially in forensic and athletic fields. The application of magnetic resonance imaging (MRI) with non-ionizing radiation can overcome this limitation in BAA. This study aimed to compare the application value of several MRI modalities of proximal humeral in BAA. A total of 468 patients with shoulder MRIs were retrospectively collected from a Chinese Han population aged 12-30 years (259 males and 209 females) for training and testing, including T1 weighted MRI (T1WI), T2 weighted MRI (T2WI), and Proton density weighted MRI (PDWI). Optimal regression models were established for age estimation, yielding mean absolute error (MAE) values below 2.0 years. The MAE values of T1WI were the lowest, with 1.700 years in males and 1.798 years in females. The area under the curve (AUC) and accuracy values of different MRI modalities of 16-year and 18-year thresholds were all around 0.9. For the 18-year threshold, T1WI outperformed T2WI and PDWI. In conclusion, the three MRI modalities of the proximal humerus can serve as reliable indicators for age assessment, while the T1WI performed better in age assessment and classification.

Estimating chronological age through learning local and global features of panoramic radiographs in the Korean population

This study suggests a hybrid method based on ResNet50 and vision transformer (ViT) in an age estimation model. To this end, panoramic radiographs are used for learning by considering both local features and global information, which is important in estimating age. Transverse and longitudinal panoramic images of 9663 patients were selected (4774 males and 4889 females with a mean age of 39 years and 3 months). To compare ResNet50, ViT, and the hybrid model, the mean absolute error, mean square error, root mean square error, and coefficient of determination (R2) were used as metrics. The results confirmed that the age estimation model designed using the hybrid method performed better than those using only ResNet50 or ViT. The estimation is highly accurate for young people at an age with distinct growth characteristics. When examining the basis for age estimation in the hybrid model through attention rollout, the proposed model used logical and important factors rather than relying on unclear elements as the basis for age estimation.

Analysis of various radiological age-assessment methods in children, adolescents and young adults regarding the differences between the sexes and sides of the body - A comparative review

A total of 76 articles published within the last twenty years, indexed in the PubMed and ResearchGate databases, were reviewed in order to compare medical imaging-based methods of age estimation of children, adolescents and young adults. The evaluated studies were analyzed for any statistically significant differences between the sexes and sides of the body, sample sizes, and population age. Irrespective of the evaluation method, there were some studies that showed a statistically significant differences in ossification stages between the male and female groups. Most of the studies whose authors conducted a statistical analysis demonstrated no significant differences between the left and right side of the body.

The fusion of ossification centers - A comparative review of radiographic and other imaging modalities of age assessment in living groups of children, adolescents, and young adults

A total of 227 articles published within the last twenty years, indexed in the PUBMED and Researchgate databases, were reviewed for the purpose of comparing medical imaging-based methods of age estimation. The evaluated studies were analyzed in terms of the assessed parts of the body, age, and epiphyseal fusion ages in children, adolescents, and young adults. Our analysis showed that an overwhelming majority of studies had been based on computed tomography and magnetic resonance imaging. A comparison of the studies showed that, irrespective of the imaging modality and the nationality of study population cohorts, the rates of development and the ages at which the process of ossification begins and ends show certain trends.

Forensic age estimation based on magnetic resonance imaging of the proximal humeral epiphysis in Chinese living individuals

Forensic age estimation in living individuals is mainly based on radiological features, but direct radiography and computed tomography lead to a rise in ethical concerns due to radiation exposure. Thus, the contribution of magnetic resonance imaging (MRI) to age estimation of living individuals is a subject of ongoing research. In the current study, MRIs of shoulder were retrospectively collected from a modern Chinese Han population and data from 835 individuals (599 males and 236 females) in the age group 12 to 30 years were obtained. A staging technique based on (Schmidt et al. Int J Legal Med 121(4):321-324, 2007) and (Kellinghaus et al. Int J Legal Med 124(4):321-325, 2010) was used and all images were evaluated with T1-wieghted turbo spin echo (T1-TSE) sequence and T2-weighed fat suppression (T2-FS) sequence. One-sided images were assessed because data from both sides were considered coincidental, as no significant differences were found (P > 0.05). Two MRI sequences were evaluated separately and subsequently compared. Regression models and supportive vector classification (SVC) models were established accordingly. The intraobserver and interobserver agreement levels were good. Compared with T1-TSE sequence, the R² values of T2-FS sequence were generally higher, while the mean absolute deviation (MAD) values were slightly lower. For T2-FS sequence, the MAD value was 1.49 years in males and 2.19 years in females. With two MRI sequences incorporated, the SVC model obtained with 85.7% correctly classified minors and 96.2% correctly classified adults in males, while 83.3% and 98.0% respectively in females. In conclusion, T2-FS sequence may slightly outperform the T1-TSE sequence in shoulder MRI analysis for age estimation, while shoulder MRIs could be a reliable prediction indicator for the 18-year threshold and two MRI sequences incorporated are encouraged.

Forensic age estimation based on fast spin-echo proton density (FSE PD)-weighted MRI of the distal radial epiphysis

Radiation exposure is a crucial factor to consider in forensic age estimation. The various magnetic resonance imaging (MRI) modalities used in forensic age estimation avoid radiation exposure. This study examined the reliability of distal radius ossification using fast spin-echo proton density (FSE PD)–weighted MRI to estimate age. Left wrist MRI findings of 532 patients aged 10–29 years were evaluated retrospectively using the five-stage system of Dedouit et al. The intra- and interobserver reliability values were κ = 0.906 and 0.869, respectively. Based on the results, the respective minimum ages estimated for stages 4 and 5 were 13.4 and 16.1 years for females, and 15.1 and 17.3 years for males; the method could not estimate an age of 18 years in any case. FSE PD MRI analysis of the distal radius epiphysis provides supportive data and can be used when evaluating the distal radius for forensic age estimation.

Evaluation of proximal humeral epiphysis ossification in 3.0 T MR images according to the Dedouit staging method: Is it be used for age of majority?

Magnetic resonance imaging (MRI) for forensic age estimation is among the research issues since it does not lead to radiation exposure. In this study, the ossification stage of the proximal humeral epiphysis was determined retrospectively in 178 male and 109 female individuals in the 12 to 30-year age group using 3.0 T MRI. All images were evaluated with the proton density fat saturated turbo spin echo (PD TSE FS) sequence and the T2 TSE FS sequence. A five-stage scoring system was used following the method of Dedouit et al. The relevant statistics were defined as minimum, maximum, mean ± standard deviation, 95% confidence interval of mean and median and the intra- and interobserver agreement levels were very good (κ > 0.80). There were no significant age differences between males and females in any of the stages (all p-values>0.05). According to the present study, stage 5 was initially observed at age 22 years for both genders. According to our results, it is possible to determine the completion of the 18th year of life in either gender on the shoulder joint. Proximal humeral epiphysis ossification may be used as an additional method for forensic age estimation through MRI.

Applicability of 3.0 T MRI images in the estimation of full age based on shoulder joint ossification: Single-centre study

Skeletal maturity is evaluated by many radiological methods for forensic age estimation. Direct radiography and computed tomography lead to a rise in ethical concerns due to radiation exposure. Therefore, magnetic resonance imaging (MRI) has currently been used in recent studies. In this study, the ossification stage of the shoulder joint was determined retrospectively in 178 male and 109 female individuals in the age group 12 to 30 years using 3.0 T MRI. All the images were evaluated with T1-weighted turbo spin echo (T1 TSE) sequence and T1 fast low angle shot two-dimensional sequence (T1 FL2D). The combined staging method, which was defined by Kellinghaus et al. and Schmeling et al., was used. The intra- and inter-observer agreement levels were very good (κ and κ_w). There were no significant age differences between males and females in all stages. In most of the stages, the ossification of the proximal humeral epiphyses occurred earlier in females than in males. Stage 4 did not occur in either of the sexes before the 18th birthday as the youngest patients in this stage was at 19 and 18 years of age in males and females, respectively. We concluded that evaluating the ossification of the proximal humeral epiphysis with MRI imaging for forensic age estimation may be beneficial. Evaluating the same anatomical structure with different MRI sequences may be useful for accurate staging diagnosis.

The relevance of body mass index in forensic age assessment of living individuals: an age-adjusted linear regression analysis using multivariable fractional polynomials

In forensic age assessment of living individuals, developmental stages of skeletal maturation and tooth mineralization are examined and compared with a reference population. It is of interest which factors can affect the development of these features. We investigated the effect of body mass index (BMI) on the developmental stages of the medial epiphysis of the clavicle, the distal epiphysis of the radius, the distal epiphysis of the femur, the proximal epiphysis of the tibia, and the left lower third molar in a total of 581 volunteers, 294 females and 287 males aged 12–24 years, using 3 T MRI. BMI values in the cohort ranged from 13.71 kg/m² in a 12-year-old female to 35.15 kg/m² in an 18-year-old female. The effect of BMI on the development of the characteristics was investigated using linear regression models with multivariable fractional polynomials. In the univariable analysis, BMI was associated with all feature systems (beta between 0.10 and 0.44; p < 0.001). When accounting for the physiological increase of BMI with increasing age, the effect of BMI was lower and in the majority of the models no longer clinically relevant. Betas decreased to values between 0.00 and 0.05. When adding feature variables to a model already including age, r² values increased only minimally. For an overall bone ossification score combining all characteristics, the adjusted ß was 0.11 (p = 0.021) and 0.08 (p = 0.23) for females and males, respectively. Low ß and r² values (0.00 (adjusted)–0.16 (crude)) were present in both models for third molar development already in the unadjusted analyses. In conclusion, our study found no to little effect of BMI on osseous development in young adults. Teeth development in both sexes was completely independent of BMI. Therefore, dental methods should be part of every age assessment.

Estimating forensic age via magnetic resonance imaging of the distal radial epiphysis

Magnetic resonance imaging is currently being studied extensively, but it is still far from being the frequently recommended radiological method for age estimation. In this study, we used magnetic resonance imaging (MRI) of distal radius ossification to obtain data for age estimation. Wrist MRI scans from 338 individuals, aged 10-29 years, were examined retrospectively using the staging system of Schmidt et al. and the extension of the stages as described by Timme et al. The results revealed that the minimum ages for stage 4a ossification were 16.0 years in women and 17.7 years in men, whereas those for stage 4b ossification were 16.6 and 18.2 years in women and men, respectively. Stage 5 was not detected in any patient. These results were comparable with those of a previous study using the same methodology with distal radial epiphysis ossification. Our finding regarding stage 4b ossification may provide valuable information on legally important age thresholds relevant to the use of MRI in evaluating the distal radial epiphysis in males. Further research needs to be conducted with large series in different populations to evaluate the triple banding at the distal radial epiphysis.