Age assessment in unaccompanied minors: assessing uniformity of protocols across Europe.

Age assessment of migrants is crucial, particularly for unaccompanied foreign minors, a population facing legal, social, and humanitarian challenges. Despite existing guidelines, there is no unified protocol in Europe for age assessment.The Forensic Anthropology Society of Europe (FASE) conducted a comprehensive questionnaire to understand age estimation practices in Europe. The questionnaire had sections focusing on the professional background of respondents, annual assessment numbers, requesting parties and reasons, types of examinations conducted (e.g., physical, radiological), followed protocols, age estimation methods, and questions on how age estimates are reported.The questionnaire's findings reveal extensive engagement of the forensic community in age assessment in the living, emphasizing multidisciplinary approaches. However, there seems to be an incomplete appreciation of AGFAD guidelines. Commonalities exist in examination methodologies and imaging tests. However, discrepancies emerged among respondents regarding sexual maturity assessment and reporting assessment results. Given the increasing importance of age assessment, especially for migrant child protection, the study stresses the need for a unified protocol across European countries. This can only be achieved if EU Member States wholeheartedly embrace the fundamental principles outlined in EU Directives and conduct medical age assessments aligned with recognized standards such as the AGFAD guidelines.

Sex determination by linear measurements of the bony labyrinth in cone-beam and computed tomography: a practical method.

PURPOSE: The determinism of the sex is of most importance for reconstruction of the biological profile of deceased individuals. In this study, we aim to implement a technique to improve the accessibility of sex determination by the study of the bony labyrinth on cone-beam computed tomography (CBCT) and computed tomography (CT) scans. METHODS: CBCT and CT scans of temporal bones performed between 2014 and 2022 were collected with demographic information. The width of the lateral (LSCw), posterior (PSCw), and anterior semicircular canal (ASCw) was measured. The primary outcome was the diagnostic performance of the individual linear measures and the product of these measures. This analysis is supplemented by establishing thresholds using ROC curves. Inter-judge and intra-judge reliability evaluation was performed blinded in randomly selected exams. RESULTS: One hundred forty-one petrous bones were included for analysis of their imaging. The analysis of the PSCw, ASCw, and ASCw*PSCw for sex determination was associated with area under curves of 0.88 ± 0.11, 0.82 ± 0.14, and 0.84 ± 0.10 respectively and accuracies of 0.74 ± 0.13, 0.78 ± 0.11, and 0.79 ± 0.13 respectively. In ROC-curve analysis, a PSCw*ASCw product > 48.5 allows to determine a male sex with > 95% specificity and a sensitivity of 50.1%. A PSCw*ASCw product ≤ 43 allows to determine a female sex with 88% specificity and 64% sensitivity. Reproducibility analyses showed good to excellent intra-judge and inter-judge reproducibility for ASCw and PSCw. CONCLUSION: Linear measurement of the semicircular canals of the vestibule on CBCT or CT could provide easy-to-use sex determination of the majority of females and males with a good predictive value.

Old World Medieval Treponema pallidum Complex Treponematosis: A Case Report.

BACKGROUND: Introduction of 1 Treponema pallidum complex pathogen in naive European populations following the return of Christopher Columbus' troops from Central America in 1493 is a central dogma in venereology. METHODS: Among skeletal elements from the seventh or eighth century uncovered in Roquevaire, France, individual RS-1003 femur macroscopically suspected of having an infectious disease was investigated by means of paleoautoimmunohistochemistry, direct metagenomics, and paleoserology, along with 1 control femur from an apparently healthy individual (R-1003) and experimental negative controls. RESULTS: RS-1003 femur showed infectious bone; paleoautoimmunohistochemistry of the lesions led to microscopic detection of a T. pallidum complex pathogen. Phylogenetic analyses comprising 71 T. pallidum complex-specific reads covering 2.37% of the T. pallidum subsp. pallidum reference genome sequence revealed an ancestral T. pallidum complex pathogen in the lesion. Paleoserology detecting T. pallidum-specific antigens confirmed positive serological findings in individual RS-1003. Individual R-1003 and the negative controls remained negative. CONCLUSIONS: This case, predating by 8 centuries previous detections of T. pallidum complex treponematosis in Europe, indicated that European populations were not naive to these pathogens before the 1493 introduction of a Central American T. pallidum complex pathogen overwhelming the T. pallidum ones previously circulating in the Old World. These data break a century-old dogma in medical microbiology.

Sex estimation from long bones: a machine learning approach.

Sex estimation from skeletal remains is one of the crucial issues in forensic anthropology. Long bones can be a valid alternative to skeletal remains for sex estimation when more dimorphic bones are absent or degraded, preventing any estimation from the first intention methods. The purpose of this study was to generate and compare classification models for sex estimation based on combined measurement of long bones using machine learning classifiers. Eighteen measurements from four long bones (radius, humerus, femur, and tibia) were taken from a total of 2141 individuals. Five machine learning methods were employed to predict the sex: a linear discriminant analysis (LDA), penalized logistic regression (PLR), random forest (RF), support vector machine (SVM), and artificial neural network (ANN). The different classification algorithms using all bones generated highly accuracy models with cross-validation, ranging from 90 to 92% on the validation sample. The classification with isolated bones ranked between 83.3 and 90.3% on the validation sample. In both cases, random forest stands out with the highest accuracy and seems to be the best model for our investigation. This study upholds the value of combined long bones for sex estimation and provides models that can be applied with high accuracy to different populations.

Intra-Individual Aging of the Facial Skeleton.

BACKGROUND: Midface skeletal changes through aging have been conceptualized as a clockwise rotation relative to the cranial base. This finding is mainly supported by cross-sectional population studies based on comparisons between groups of individuals in different age ranges. Few papers have evaluated the intra-individual evolution of the facial skeleton, and those that have included only a limited number of patients. OBJECTIVES: The authors sought to analyze the intra-individual evolution of the facial skeleton. METHODS: We conducted a retrospective study including patients who underwent 2 separate facial computed tomography scans (T1 and T2) with a minimum gap of 7 years. Employing 3-dimensional reconstructions, we measured and compared 7 facial angles (glabellar, orbital, piriform, maxillary, subdental, chin, gonial) and 6 facial distances (lacrimal crest, orbital floor, piriform, zygoma, labiomental, gnathion) on both computed tomography scans. RESULTS: A total of 56 patients (29 males and 27 females) were included. Mean ages at T1 and T2 were 50 and 59 y, respectively. We found a significant decrease between T1 and T2 in facial angles at the midface (glabella, orbital, piriform, and maxillary angles, all P < 0.0001). We found a significant increase in all facial distances between T1 and T2 for the overall population and for men (all P < 0.05). For women, all distances increased, but only piriform and zygoma distances showed significant changes (P < 0.001 and P < 0.04, respectively). Bone remodeling appeared earlier in women. CONCLUSIONS: Our study confirms the clockwise rotation of the midface during aging. This finding could lead to a better understanding of aesthetic medicine practices.

Maturation of the human foetal basioccipital: quantifying shape changes in second and third trimesters using elliptic Fourier analysis.

During prenatal development, the brain is considered the best maturation criterion for the estimation of foetal physiological age, regardless of the conditions of pregnancy. Unfortunately, the brain lyses very quickly after death, but fortunately, the brain also has a major influence over osseous structures of the cranial base during development. Therefore, we considered the osseous structures of the cranial base potential indirect maturation indicators of foetal age. Because of its early formation and robustness, the basioccipital is a cranial base bone that is often used for studies in biological anthropology. Studies generally use conventional morphometry and bone size ratio to highlight morphological changes occurring during the foetal period and to create age estimation methods. These methods usually define thresholds beyond which the morphology of the basioccipital changes, but do not fully consider the form that might be valuable precisely to visualize its development or improve age estimation methods. Using geometric morphometric methods, the present study aims to analyse the development of the basioccipital during the second and third trimesters of foetal life by quantifying and visualizing shape changes in the inferior view. Basioccipital shapes are used as direct indicators of the maturation of the cranial base and as indirect indicators of the maturation of the brain and, by extension, the whole body. A sample of 221 anonymized computed tomographic (CT) scans of normal foetuses, ranging from 18 to 41 gestational weeks (GW), was used. Elliptic Fourier analysis (EFA) was used to quantify the basioccipital outline, and maturation stages were established to visualize shape changes with a principal component analysis. Our study allowed us precisely to quantify and continuously visualize shape changes occurring during prenatal life. Additionally, this study provides the first evidence of two distinct linear shape trajectories of the basioccipital. Foetuses aged between 18 and 26 GW have a rapid shape change with well-individualized stages, whereas shape changes are less visible in the second trajectory (27-41 GW). Furthermore, intra-stage shape variation is higher for the basioccipital at the beginning of the second and third trimesters than at the first trimester. By using geometric morphometric methods and EFA, this study shows that it was possible to go beyond classical methods. Indeed, the developed methodology enabled the first quantification of the overall shape changes of the basioccipital between gestational ages. The morphological shape changes throughout the foetal period can be useful for anthropological studies and provide new perspectives for immature age estimation methods.

Geometric morphometric contribution to septal deviation analysis.

PURPOSE: The nasal septum presents inter-individual conformational variations. The objectives of this study were to establish a validated protocol for nasal septum analysis using geometric morphometrics (GM) to establish a classification of septal deviations (SD). METHODS: This was a retrospective study including two groups of patients: patients operated on by septoplasty (SD group) and patients without nasal obstruction (control group). The 3D segmentation model was extracted from CT scans. Thirty landmarks were defined on the nasal septum and validated by MANOVA Procrustes. Using a clusterization process, the septum was classified to reflect its different conformations. Nasal resistances were compared between the two groups. RESULTS: Fifty scans of patients with SD were included. The percentage of variability due to measurement error was 7.9% across all landmarks. We identified two clusters for the SD group. Using GM, conformation of cluster 1 (S-shaped) and cluster 2 (C-shaped) was visualized and identified. There was a statistically significant difference regarding nasal resistance between each cluster in the SD group compared with the control group (p < 0.05). CONCLUSIONS: This work is a first step in SD exploration, contributing to a clearer appreciation of the interactions between nasal conformation and function. An SD classification was devised based on a reliable and reproducible statistical analysis. Enhanced understanding of conformation/function interactions will improve the diagnosis and treatment of nasal obstruction.

Developmental stability and environmental stress: A geometric morphometrics analysis of asymmetry in the human femur.

OBJECTIVES: The evaluation of developmental stability (DS) by measuring fluctuating asymmetry (FA), a bioindicator of general cumulative stress, is an approach that has often been used to characterize health status in past populations. New techniques of geometric morphometrics now enable a better appreciation of FA than before, with a more refined quantification of variation. The aim of our study is to determine the effectiveness of geometric morphometrics analyses of asymmetry in the human femur for the study of individual DS and inferring health status of human populations. MATERIALS AND METHODS: We conducted a comparative analysis between two diachronic populations of distinct and known health status. Two samples of 70 pairs of adult femurs from individuals of comparable age range and sex were selected and CT-scanned. For each 3D reconstruction, two sets of 27 landmarks were digitized to quantify and minimize the effect of measurement error on the evaluation of FA. RESULTS: While the measurement of FA in femoral centroid size seemed comparable between the samples, the amount of FA in femoral shape differed. Individuals who experienced high levels of environmental stress presented higher intra-individual variation. In parallel, results did not reveal any significant differences in DS between sexes or age groups. DISCUSSION: The geometric morphometrics analysis of femoral asymmetry was effective for distinguishing two populations. After considering various factors of influence, genetics and biomechanics seem to have a limited impact on the results. Expressing FA appears to be normal but dependent on the disturbances of DS produced by environmental stress.

Comparison of macroscopic and microscopic (stereomicroscopy and scanning electron microscopy) features of bone lesions due to hatchet hacking trauma.

This experimental study examined the lesions produced by a hatchet on human bones (tibiae). A total of 30 lesions were produced and examined macroscopically (naked eye) and by stereomicroscopy. 13 of them were also analyzed using scanning electron microscopy. The general shape of the lesion, both edges, both walls, the kerf floor and the extremities were described. The length and maximum width of the lesions were also recorded. The microscopic analysis of the lesions led to the description of a sharp-blunt mechanism. Specific criteria were identified (lateral pushing back, fragmentation of the upraising, fossa dug laterally to the edge and vertical striae) enabling the forensic expert to conclude that a hacking instrument was used. These criteria are easily identifiable using scanning electron microscopy, but can also be observed with stereomicroscopy. Overall, lateral pushing back and vertical striae visible using stereomicroscopy and scanning electron microscopy signal the use of a hacking tool.

Analysis of Hyoid-Larynx Complex Using 3D Geometric Morphometrics.

The aim of this study was to obtain a quantitative anatomical description of the hyoid bone-larynx complex using modern 3D reconstruction tools. The study was conducted on 104 bones from CT scan images of living adult subjects. Three-dimensional reconstructions were created from CT scan images using AVIZO 6.2 software package. A study of this complex was carried out using metric and morphological analyses. Characteristics of the hyoid bone and larynx were highly heterogeneous and were closely linked with the sex, height, and weight of the individuals. Height and width of larynx were significantly greater in men than in women (24.99 vs. 17.3 mm, p ≤ 0.05 and 46.75 vs. 41.07, p ≤ 0.05), whereas the thyroid angle was larger in females (81.12° vs. 74.48°, p ≤ 0.05). There was a significant correlation between the height and weight of subjects and different measurements of the hyoid-larynx complex. (Pearson's coefficient correlation r = 0.42, p ≤ 0.05 between the height of thyroid ala and the height of subjects and r = 0.1, p ≤ 0.05 between the height of thyroid ala and the weight of subjects). Shape and size analysis of the hyoid-larynx complex showed the existence of a significant sexual dimorphism and high interindividual heterogeneity depending to patient morphology. These results encourage us to go further with functional and imaging correlations.

Age determination of adult individuals by three-dimensional modelling of canines.

Accurate age determination is fundamental in both forensic medicine and anthropology. Many methods that relate dental characteristics to adult age have been proposed, but there is still no simple and reliable method that does not damage the study material. The aim of this work was to propose a relevant and practical technique for determining age in adults that could be used in both living and deceased individuals. The sample was composed of 210 CT scans from individuals aged from 15 to 85 years old, with four healthy canines present in the mouth. The 840 canines were modelled using Mimics® 10.01 software. The pulp volume/total volume ratio ×100 was determined for each tooth. Seven mathematical models, corresponding to all possible real situations, were determined by the weighted least squares method and ranked in order of relative performance. The adequacy of the seven models to the data was very high with the regressions proposed (0.915 < R (2) adjusted < 0.964). Ranked in order of performance, the maxillary model was the most powerful of the seven models for age determination, followed by the 4 canines model, the 13 model and the 23 model.

Fetal age estimation using MSCT scans of the mandible.

The purpose of this study was to examine a documented fetal collection, to carry out morphometric analysis of femoral length and of the mandible, and to develop diagnostic standards for estimating fetal age at death based on multislice computed tomography (MSCT) reconstructions. The sample was composed of 81 fetuses, whose ages were recorded in weeks of amenorrhea (WA) between 20 to 40 WA. The measurements made were femoral length (FL) and six distances and four angles of the mandible. Femoral length was measured in 81 fetuses (39 females and 42 males). Morphometric study of the mandible was carried out in 65 fetuses (31 females and 34 males), as the mandible was missing in 16 fetuses. R software was used for statistical analyses. Coefficient correlation (R(2)) and linear regression formulas were calculated. Intra-observer and inter-observer variabilities were very satisfactory (intra-class correlation coefficient ≥0.95). Our method appears to be reliable and reproducible. Femoral length was most strongly correlated with age (R(2) = 0.9). The measurement of six distances and four mandible angles from four landmark positions showed a correlation similar to the femoral length correlation (R(2) ≥ 0.72). The results of this study agreed with those of the literature. We conclude that the mandible is a reliable indicator for estimating fetal age at death. Moreover, MSCT has been shown to be an innovative and reliable technology for this purpose.

Fetal age estimation using MSCT scans of deciduous tooth germs.

Evaluation of fetal age is an essential element in many fields such as anthropology, odontology, paleopathology, and forensic sciences. This study examines the correlation between fetal age, femoral diaphyseal length (considered as the gold standard), and deciduous tooth germs of fetuses aged 22 to 40 weeks amenorrhea (WA) based on computed tomography (MSCT) reconstructions. Qualitative and quantitative studies of femoral and deciduous tooth germ lengths were performed on 81 fetuses (39 females and 42 males). R software was used for statistical analyses. Intra-observer and inter-observer variabilities and the interclass correlation coefficient (ICC) were calculated. Correlation coefficients (R (2)) and linear regression equations were calculated. Intra- and inter-observer variabilities were very satisfactory (intra-observer ICC ≥ 0.96, inter-observer ICC ≥ 0.95). Femoral length was significantly correlated with age (R (2) = 0.9). The correlation coefficient between age and height, width, and dental volume was R (2) ≥ 0.73. Tooth germs were good indicators of fetal age. Our method appears to be reliable and reproducible, and the results of this study agreed with those of the literature. The dental formula provided a precise estimation of fetal age between 25 and 32 WA. Tooth germs were reliable indicators of fetal age, and multislice computed tomography was shown to be an innovative and reliable technology for this purpose.

Analysis of swallowing after partial frontolateral laryngectomy with epiglottic reconstruction for glottic cancer.

The aim of the study was to evaluate swallowing using a reproducible objective methodology and to seek preoperative factors that could influence swallowing outcomes in patients operated on for partial laryngectomy. Twenty-four patients who underwent partial frontolateral laryngectomy with epiglottic reconstruction for T1bN0 or T2N0 glottic carcinoma between 2008 and 2012 were retrospectively evaluated. Using fiberoptic endoscopic and videofluoroscopic evaluation, early (15 days postoperatively) and late (2 months postoperatively) scores were obtained for all patients to quantify their swallowing skills. Eighty-three percent of patients achieved at least partial oral feeding at time of hospital discharge and 87.5% achieved exclusive oral feeding within 2 months postoperatively. Early score was good or excellent in 50%, average in 4.2% and poor in 41.8%. Regarding late scores, 63% were classified as having a good or excellent late score, 7 patients (29%) were classified as "middle result" because their time to recover was longer (i.e. between 1 and 2 months postoperatively), and two patients had a poor late score. Finally, at last follow-up, only one patient was partially fed by gastrostomy (180 days after surgery). T stage (p = 0.04) was the only factor influencing early swallowing outcomes and length of hospital stay was longer for poor scores than for good late results (p = 0.02). Our findings show good outcomes in terms of postoperative swallowing. Objective assessment of deglutition is essential for a better understanding of the mechanisms of postoperative swallowing disorders and for patient selection.

Hair analysis in postmortem investigations: Case of a skeletonized body.

Analysis of hair collected from putrefied or skeletal bodies is always complex and must take into account several pitfalls, such as external contamination and contamination by biological fluids. This work presents a case of particular complexity. A skeletonized body was discovered on a country road. A tuft of brown hair, detached from the scalp, irregular in length, non-oriented, in contact with soil and vegetation, was removed. An anthropological examination was carried out and genetic samples were taken from the right femoral shaft. After about 10 washes with warm water and dichloromethane, the tuft of hair was analyzed without segmentation. General unknown screening was performed by liquid chromatography system coupled to a high-resolution mass spectrometry (LC-HRMS) after incubation in pH 9.5 borate buffer and liquid-liquid extraction. Specific Multiple Reaction Monitoring (MRM) methods for date rape drugs were carried out by liquid chromatography system coupled to a tandem mass spectrometry (LC-MS/MS). The anthropological examination allowed to determine that the victim was a female individual, over 60 years old, the death dating from 3 months to 1 year. Comparison of the DNA results with the Missing Persons Index led to the identification, a 60-year-old woman who disappeared 5 months earlier. Hair analysis showed the presence of oxazepam (361 pg/mg), nordiazepam (54 pg/mg), and alimemazine (5 pg/mg). The interpretation of these concentrations is extremely difficult due to the risk of degradation of the hair cuticle during prolonged stay in the soil, as well as of contamination by putrefactive fluids. The authors discuss the value of using multiple biological and non-biological matrices in this context to improve the interpretation of the results.

Technical note: Interest of focused fields in post-mortem computed tomography using photorealistic images for age at death estimation from the pubic symphysis.

INTRODUCTION: The morphological assessment of the pubic symphysis using the Suchey-Brooks method is considered a reliable age at death indicator. Age at death estimation methods can be adapted to the images obtained from post-mortem computed tomography (PMCT). The aim of this study is to evaluate the utility of pubic symphysis photorealistic images obtained through Global illumination rendering (GIR) for age at death estimation from whole-body PMCT and from focused PMCT on the pubic bone. MATERIALS AND METHODS: We performed virtual age at death estimation using the Suchey Brooks method from both the whole-body field of view (Large Field of View: LFOV) and the pubis-focused field of view (Small and Field of View: SFOV) of 100 PMCT. The 3D photorealistic images were evaluated by three forensic anthropologists and the results were statistically evaluated for accuracy of the two applied PMCT methods and the intra- and inter-observer errors. RESULTS: When comparing the two acquisitions of PMCT, the accuracy rate reaches 98.5% when using a pubic-focused window (SFOV) compared to 86% with a whole-body window (LFOV). Additionally, the intra- and inter-observer variability has demonstrated that the focused window provides better repeatability and reproducibility. CONCLUSION: Adding a pubic-focused field of view to standard PMCT and processing it with GIR appears to be an applicable technique that increases the accuracy rate for age at death estimation from the pubic symphysis.

Effects of fall conditions and biological variability on the mechanism of skull fractures caused by falls.

In a forensic investigation, there is considerable difficulty in distinguishing between different mechanisms that could explain the head injury sustained. The key question is often whether the injury was the consequence of a fall, a blow, or a fall caused by a blow. Better understanding of the parameters influencing the mechanism of skull fracture could be of use when attempting to distinguish between different causes of injury. Numerous parameters concerning fall conditions and biological variability are reported in the literature to influence the mechanism of skull fracture. At the current time, there are no studies that investigate both the effect of a fall and biological parameters. The aim of this paper is to study the influence of these parameters on the mechanism of skull fracture using a numerical approach. We focused on accidental falls from a standing height. A multibody model was used to estimate head impact velocities and a finite element model was used to investigate the effect of the fall conditions and of biological variability on skull fracture. The results show that the mechanism of skull fractures is influenced by a combination of at least four parameters: impact velocity, impact surface, cortical thickness and cortical density.

Analysis of hyoid bone using 3D geometric morphometrics: an anatomical study and discussion of potential clinical implications.

The aim of this study was to obtain a quantitative anatomical description of the hyoid bone using modern 3D reconstruction tools and to discuss potential applications of the knowledge in clinical practice. The study was conducted on 88 intact hyoid bones taken from cadavers during forensic autopsies (group 1) and on 92 bones from CT scan images of living adult subjects (group 2). Three-dimensional reconstructions were created from CT scan images using Amira 5.3.3® software. An anatomical and anthropological study of hyoid bones was carried out using metric and morphological analyses. Groups 1 and 2 were compared to evaluate the influence of muscle traction on hyoid bone shape. Characteristics of the hyoid bone were highly heterogeneous and were closely linked with the sex, height, and weight of the individuals. Length and width were significantly greater in men than in women (39.08 vs. 32.50 mm, p = 0.033 and 42.29 vs. 38.61 mm, p = 0.003), whereas the angle between the greater horns was larger in females (44.09 vs. 38.78, p = 0.007). There was a significant positive correlation between the height (Pearson coefficient correlation r = 0.533, p = 0.01) and weight (r = 0.497, p = 0.01) of subjects and the length of the hyoid bone. Significant metric differences were shown between group 1 and group 2. This very reproducible methodology is important because it may lead to clinical studies in, e.g., head and neck cancer or sleep apnea. Such studies are ongoing in our research program.

Morphometric measurements and sexual dimorphism of the piriform aperture in adults.

PURPOSE: The aim of this study was to evaluate the dimensions (maximal width and length), the size and the shape of the PA and their sexual dimorphism. METHODS: Using 3D-CT scan reconstructions and landmarks positioning around the piriform aperture and on the face, a collective of 170 non-pathologic subjects (79 female, 91 male) from Marseille (France) was examined in classical and geometric morphometrics methods. RESULTS: The mean width of the piriform aperture was 24.00 mm in females and 25.32 mm in males, the mean length was 32.54 mm in females and 36.35 mm in males. The difference between males and females was significant, and our data correlates well with the previously data acquired from humans skulls. Facial measurements also showed a statistically significant dimorphism. In morphometric geometrics, the correlation between the centroïd size and PC1 in the shape space was weak, while this correlation was strong in the size and shape space. Visualization of shape differences was achieved on 2D wireframes. CONCLUSION: Shape and size analysis of the piriform aperture showed the existence of a significant sexual dimorphism. These results encourage us to go further with functional and imaging correlations.

New models to estimate fetal and young infant age with the pars basilaris biometry.

The pars basilaris of the occipital bone is often found intact when fetal or infant bones are discovered. In the literature, several methods use measurements of this bone for juvenile's age-at-death estimation, but it has already been demonstrated that they can come along methodological and statistical biases. In this study, new age prediction formulas were created from a learning sample of 208 CT scans of fetuses and infants from Marseilles (France) with normal development. The two statistically validated models, with a prediction interval of 95 % of reliability, were tested on a separate sample of 68 individuals, for which we ensured that they did not show any developmental pathology. Models show an average of 97.06 % of correct age estimates, compared to less than 26.6 % when using previously published which tend to overestimate age. The new age estimation formulas make it possible to estimate fetuses and infants age with very good results up to 2 postnatal months. Results are both reliable and precise enough for forensic practice, and we provide an automated tool (a simple excel spreadsheet) to ensure an easy and quick access to the application of this method.