Fetal facial bone growth: Post-mortem CT analysis.

OBJECTIVE: To describe and model the normal growth of fetal facial bones and angles. MATERIAL AND METHODS: A total of 118 fetal CT scans obtained at 19 to 41 weeks gestation after in utero fetal death or late miscarriage were analyzed. CT scan was followed by autopsy and pathological examination and only fetuses free from brain disease or abnormal craniofacial development were included. The measurements were taken using software for frontal, sagittal and 3D reconstruction from native axial sections. The optimal plane for bone analysis was chosen and the measurements made by multiplanar reconstruction. RESULTS: There was a statistically significant increase (P<0.001) in all measurements regardless of gestational age (GA) except those of the mandibulo-fronto-maxillary angle (P=0.412), the naso-mandibulo-maxillary angle (P=0.828) and mandibular width (P=0.86). There was no significant difference according to fetal sex. Based on these results, the corresponding growth curves were created. The anteroposterior mandibular diameter (APD) was very strongly correlated with GA (R=0.926, P<0.001). The following equation: GA=(8.187×APD)+4.257 can be used to estimate GA with a confidence interval (CI) of±2.42. The same applies to maxillary width (MW) (R=0.922; P<0.001). The equation GA=(11.059×MW)+7.571 can be used to estimate GA with a CI of 2.17. CONCLUSION: The growth of the mandible, maxilla, zygomatic bone and orbits was measured and the corresponding growth curves were established. Several measurements were strongly correlated with gestational age.

Ontogeny of cranial base during the first two years of life.

The integration of the growth of the brain and the cranial base suggests that each system may influence the other, notably during the first three years of life, although this influence has never been proven to be exclusive. The aim of our work was to analyse the dynamics of normal growth on the one hand, and the development and ontogenetic allometry of the cranial base in the infant on the other hand. MATERIAL AND METHOD: A total of 32 infants (17 males/15 femeles) having been included in the unexpected infant death french protocol were analyzed. Three-dimensional reconstructions of the cranial base were performed from CT scans. The technique combined manual segmentation of regions of interest, contour extraction and surface reconstruction. Nineteen landmarks were positioned on each of the bone surfaces. RESULTS: No correlation was observed between sex assigned at birth and shape, weight, crown-heel length, or head circumference. Principal component analysis showed that 85.5% of the variance observed on the first component was secondary to growth. After Procrustes superimposition, 25% of the shape variance observed was explained by the first principal component. It showed anteroposterior lengthening of the cranial base. In addition, the height, width and length of the posterior fossa increased and the relative position of the basion was displaced inferiorly and anteriorly with flexion of the sphenoid angle. Negative allometry was also observed. CONCLUSION: Our study, carried out in a rigorously selected population of infants, presents a fundamental approach to ontogeny through study of shape, growth and ontogenetic allometry.

Study of the growth and shape of the brain and cranial base during the first two years of life.

Ontogeny of the cranial base and the brain integrates data on growth, maturation and ontogenetic allometry of these two systems in the course of development. The aim of our work was to study the ontogeny of the cranial base and the brain in order to understand their growth dynamic and shape changes using a traditional morphometric approach in individuals with normal (non-pathological) development. MATERIEL AND METHOD: Forty-seven infants having been included in the unexpected infant death french protocol were analyzed. Medical imaging (CT and MRI) exams, followed by an autopsy and pathology examination allowed us to include only infants free from brain disease or pathology affecting growth. RESULTS: Testing of measurement reliability validated 12 distances and 3 angles as well as the positioning of the landmarks that had been used to obtain the distances and the angles. No correlation between sex and the various variables studied was found. However, a correlation was observed between these variables and age, making it possible to propose a growth curve. A medium to strong correlation was found between brain variables and the bone variables of the cranial base, underlining the parallel development of the two systems. CONCLUSION: Our study, carried out in a rigorously selected population of infants, presents a fundamental approach to the study of ontogenesis.

Biomechanical study of the thyroid cartilage: A model of bi-digital strangulation.

The presence of fracture on neck elements is an indication of violence. Both the hyoid bone and the larynx can be damaged by a strangulation mechanism. Thyroid cartilage, more specifically, may present lesions in response to this mechanical stress. These lesions result in fractures at the bases of the horns of the thyroid cartilage. This study focuses on the thyroid cartilage behavior in cases of bi-digital strangulation, using an anthropometric and biomechanical approach. To develop a biomechanical model, we performed an anthropometric study taking into account 14 distances measurements as well as 3 measurements of angles. These measures allowed us to determine a significant sexual dimorphism between individuals. Then, we define 6 morphologies models, composed of 3 females and 3 males individuals. In order to visualize the ossification of the cartilage, each model has been tested with bone properties. Strangulation cases were simulated by applying an imposed velocity of 0.4m/s then 1m/s. We observed different behaviors of the thyroid cartilage according to the sex and the morphology.

Virtual reconstruction of paranasal sinuses from CT data: A feasibility study for forensic application.

PURPOSE: The purpose of this study was to report the feasibility of computed modelization and reconstitution of the paranasal sinuses, before and after trauma, from CT data. MATERIALS AND METHODS: We modeled and reconstructed the paranasal sinuses of two patients (A and B), before and after trauma, using two different softwares (3DSlicer® and Blender®). Both patients had different numbers and locations of fractures. The 3DSlicer® software was used to create a 3D model from CT data. We then imported the 3D data into the Blender® software, to reconstruct and compare the dimensions of the paranasal sinuses before and after trauma. RESULTS: The 3 fragments of patient A and the 7 fragments of patient B could be repositioned in the pre-traumatic configuration. Distance measurements proved to be similar between pre- and post-traumatic 3D volumes. CONCLUSION: After simple trauma, bone facial anatomy reconstruction is manually feasible. The whole procedure could benefit from automatization through machine learning. However, this feasibility must be confirmed on more severely fractured paranasal sinuses, to consider an application in forensic identification.

Characterization of the perinatal mandible growth pattern: preliminary results.

PURPOSE: The fetal development of the mandible is nowadays quite understood, and it is already known that craniofacial growth reaches its highest rate during the first 5 years of postnatal life. However, there are very few data focusing on the perinatal period. Thus, the present article is addressing this concern by studying the mandible morphology and its evolution around the birth with a morphometric method. METHODS: Thirty-one mandibles modelled in three dimensions from post-mortem CT-scans were analyzed. This sample was divided into two subgroups composed of, respectively, 15 fetuses (aged from 36 gestational weeks), and 16 infants (aged to 12 postnatal weeks). 17 distances, 3 angles, and 8 thicknesses were measured via the prior set of 14 landmarks, illustrating the whole mandible morphology. RESULTS: Although this methodology may depend on the image reconstruction quality, its reliability was demonstrated with low variability in the results. It highlighted two distinct growth patterns around birth: fetuses mandibles do not significantly evolve during the perinatal period, whereas, from the second postnatal weeks, most of the measurements increased in a homogeneous tendency and in correlation with age. CONCLUSIONS: The protocol developed in this study highlighted the morphologic evolution of the mandible around birth, identifying a different growth pattern from 2 postnatal weeks, probably because of the progressive activation of masticatory muscles and tongue. However, considering the small sample size, these results should be thorough, so identification and management of anatomic abnormalities could eventually be achieved.

Which Foetal-Pelvic Variables Are Useful for Predicting Caesarean Section and Instrumental Assistance?

OBJECTIVE: To assess the variables useful to predict caesarean delivery (CD) and instrumental assistance, through the analysis of a large number of foetal-pelvic variables, using discriminant analysis. MATERIALS AND METHODS: One hundred and fourteen pregnant women were included in this single-centre prospective study. For each mother-foetus pair, 43 pelvic and 18 foetal variables were measured. Partial least squares-discriminant analysis was performed to identify foetal-pelvic variables that could statistically separate the 3 delivery modality groups: spontaneous vaginal delivery (SVD), CD, and instrument-assisted delivery (IAD). RESULTS: For the SVD versus CD model, voluminous foetuses and women with a narrow pelvic inlet had a greater risk for requiring CD. The most efficient variables for discrimination were the transverse diameter and foetal weight. The antero-posterior inlet and obstetric conjugate were considered in this model, with the former being a useful variable but not the latter. For the SVD versus IAD model, the most important variables were the foetal variables, particularly the bi-parietal diameter. Women with a reduced antero-posterior outlet diameter and a narrow pubic arch were more at risk of requiring an IAD. CONCLUSION: The antero-posterior inlet was an efficient variable unlike the obstetric conjugate. The obstetric conjugate diameter should no longer be considered a useful variable in estimating the arrest of labour. Antero-posterior inlet diameter was a sagittal variable that should be taken into account. The comparison of sub-pubic angle and bi-parietal and antero-posterior outlet diameters was useful in identifying a risk of requiring instrumental assistance.

Use of 3D orbital reconstruction in the assessment of orbital sexual dimorphism and its pathological consequences.

INTRODUCTION: Surrounded by a variety of structures including the facial sinuses and the brain, the human orbit displays unique anatomical features. It is known that orbital volume correlates with age and sex. The aim of this study was to evaluate sexual dimorphism of orbital volume relative to the size of the skull, and to establish criteria for gender determination. METHODS: Orbital volume was measured from 3D models of the orbits. The volumes were expressed in relation to the centroid size of the skull, to ensure that any sexual dimorphism in orbital volume was not simply due to a difference in skull size. Thirty-three male and 42 female subjects were included in the study. RESULTS: The volume of both orbits were significantly higher in men than in women (P=0.0001). The right, left and total orbital volumes relative to the centroid skull size were also significantly higher in men than women (P<0.05). The method was repeatable and reproducible. A test of gender determination was developed, with a precision of 77.3%. DISCUSSION: This is the first study showing a sexual dimorphism in orbital volume relative to skull size. This difference in volume could explain the greater predisposition to myopia in women and their more frequent need for orbital decompression in thyroid orbitopathies.

Forensic use of the Greulich and Pyle atlas: prediction intervals and relevance.

OBJECTIVE: The Greulich and Pyle (GP) atlas is one of the most frequently used methods of bone age (BA) estimation. Our aim is to assess its accuracy and to calculate the prediction intervals at 95% for forensic use. METHODS: The study was conducted on a multi-ethnic sample of 2614 individuals (1423 boys and 1191 girls) referred to the university hospital of Marseille (France) for simple injuries. Hand radiographs were analysed using the GP atlas. Reliability of GP atlas and agreement between BA and chronological age (CA) were assessed and prediction intervals at 95% were calculated. RESULTS: The repeatability was excellent and the reproducibility was good. Pearson's linear correlation coefficient between CA and BA was 0.983. The mean difference between BA and CA was -0.18 years (boys) and 0.06 years (girls). The prediction interval at 95% for CA was given for each GP category and ranged between 1.2 and more than 4.5 years. CONCLUSION: The GP atlas is a reproducible and repeatable method that is still accurate for the present population, with a high correlation between BA and CA. The prediction intervals at 95% are wide, reflecting individual variability, and should be known when the method is used in forensic cases. KEY POINTS: • The GP atlas is still accurate at the present time. • There is a high correlation between bone age and chronological age. • Individual variability must be known when GP is used in forensic cases. • Prediction intervals (95%) are large; around 4 years after 10 year olds.

Maxillary sinus volume: new physiopathological data in fungal ball genesis? A retrospective study.

OBJECTIVES: The goal of this study was to compare maxillary sinus (MS) volume in patients with, or without, maxillary fungal ball. DESIGN: Monocentric retrospective study performed on 115 patient CT scans. SETTINGS: We defined two groups of patients according to the absence (control group) or the presence (fungal ball group) of unilateral fungal ball in the MS. Sinus 3D reconstruction was created from CT scan. PARTICIPANTS: Control group: 71 patients (36 women - 50.7%); mean age was 51 years. Fungal ball group: 44 patients (29 women - 65.9%); mean age was 54.5 years. MAIN OUTCOME MEASURE: The univariate association between MS volume and sinus covariates was tested by anova. Multivariate analysis was made including all variables statistically significant in univariate analysis. RESULTS: In the control group, mean MS volume was 14 766 mm3 . The volumes of the two MSs were not statistically different in the control group (P = 0.145). In the fungal ball group, mean MS volume was 15 982 mm3 . Fungal ball was found in the smallest MS in 41 of 44 cases. Univariate analysis showed a statistical difference between the pathological and the non-pathological MS volumes (P < 10-4 ). Multivariate analysis confirmed the correlation between MS volume and the presence of a fungal ball (P < 10-4 ). CONCLUSIONS: This study suggests that maxillary fungal ball is associated with a smaller size of the affected MS.

Anatomical basis of the coordination between smooth and striated urethral and anal sphincters: loops of regulation between inferior hypogastric plexus and pudendal nerve. Immuno-histological study with 3D reconstruction.

PURPOSE: (1) Describe both nervous pathways to the sphincters, and highlight the anatomical support of their coordination. (2) Obtain a 3D representation of this complex innervation system. METHODS: A computer-assisted anatomical dissection technique was used. Serial histological sections were cut in the pelvis of four female human foetuses (aged 19-32 weeks of gestation). The sections were treated with conventional staining, and with seven different immunostainings. The sections were digitalized and, finally, a 3D representation was built from the corresponding images. RESULTS: Myelinated and sensory fibres were detected at the inferior hypogastric plexus (IHP) level. Our analysis showed that most of the afferent sensory fibres come from the urinary and anal sphincters through the anterior and posterior branches of the IHP respectively. A highly positive nitrergic (anti-NOS1) and sensitive (anti-CGRP) labelling was found in the external layer of the urethral sphincter. The 3D representation allowed describing the two components of the innervation system. A sensory-motor regulation loop was found for both sphincters. CONCLUSION: A 3D description of the components of both nervous pathways to the sphincters has been established. Our findings on the innervation of the sphincters tend to question the classical infra/supra levatorian muscle description. The coordinated work of the internal and external layers of the anal and urethral sphincter is probably mediated by multiple roles regulation.

[A look into the past: improves in obstetrical and neonatal outcome in maternity since the 19th century]. / Un regard dans le passé : évolution du devenir materno-fœtal en maternité depuis le xixe siècle.

OBJECTIVE: Evaluate changes in obstetrical and neonatal outcome of women who delivered in maternity hospital since the 19(th) century. MATERIALS AND METHODS: Data from a historic cohort of 1022 women who delivered between 1871 and 1874 in the hôtel Dieu hospital of Marseille were compared to those from 1159 women who delivered from 2005 to 2006 in the level 3 maternity of Nord hospital of Marseille (contemporary cohort). Deliveries that had occured before 22 weeks and/or with a foetal birth weight of less than 500 g were excluded. RESULTS: A total of 2131 pregnancies were included: 1011 and 1120 in historic and contemporary cohort, respectively. Despite comparable mean term of delivery, mean birth weight of neonates from historic cohort were significantly lower: 2971 g (550-4900 g) vs 3250 g (500-5375 g), respectively (p<0.001). Stillbirths were reported in 72 (7.1%) cases in historic cohort compared to nine (0.8%) in contemporary cohort (p<0.001). Neonatal mortality was 3.7% in historic cohort and 1.9% in contemporary cohort (p=0.012). A total of 99 (9.8%) maternal deaths were reported in historic cohort, while none in contemporary cohort (p<0.001). A wide majority of maternal deaths were caused by maternal infection (72.9%); 5.2% were caused by postpartum haemorrhage. CONCLUSION: Our results illustrate the tremendous impact on maternal and neonatal outcome of advances in obstetrical management. The significant increase in the median foetal birth weight is likely to be related to wide changes in environmental conditions and behaviour.

3D CT scan study of fetal cranial base: interests of occipital bone measurements in age estimation.

OBJECTIVES: Cranial base development during fetal life is of major interest for many research purposes. In this study, we focused on fetal age estimations which are extremely important in forensic contexts. Nevertheless, there have been very few studies using occipital measurements to determine fetal age. OBJECTIVES: To evaluate change in the sagittal length/maximum width ratio of the basilar part of the occipital bone and to propose a simple and reliable method for fetal age determination. METHODS: A sample of 30 male and 7 female fetuses aged 24 to 41 weeks amenorrhea underwent CT scan. Occipital bones were reconstructed (Amira 4.0) and measurements were carried out on each part. RESULTS: A multivariate analysis (ANOVA) gave an age formula using right exoccipital measurements and a linear regression supplied the age of reversion of the sagittal length/maximum width ratio. CONCLUSION: This preliminary study clearly highlighted the promises of 3D CT-Scan studies of fetal cranial base and gave interesting results and the method deserves to be tested on a larger sample.

[Value of the sesamoid bone of the thumb in the determination of bone age]. / Quelle valeur accorder à l'os sésamoïde du pouce dans la détermination de l'âge osseux?

PURPOSE: To assess the presence of ossification of the sesamoid bone of the thumb as a function of age and compare the results to data from the atlas by Greulich and Pyle describing the ossification of this bone in girls of 11 years and boys of 13 years. Materials and methods. Prospective study of 1372 children (780 boys and 592 girls between the ages of 0.4 and 19.7 years, mean age of 9.7 years) with known chronological age requiring radiographic evaluation of the wrist-hand after minor trauma. The presence of a sesamoid was analyzed by logistic regression using the method of probits. RESULTS: The minimum and maximum ages in our sample population were 10-15.1 years for boys and 8.8-15.2 years for girls. The P50 value (method of probits) corresponded to the chronological age at which 50% of the population had a visible sesamoid. It was 12.1 years for boys and 10.2 years for girls. CONCLUSION: The timing of ossification of the sesamoid of the thumb is widely variable. Ossification of this sesamoid should not be used as a precise indicator when determining bone age using the atlas by Greulich and Pyle.

[Pelvic incidence reliability in spine sagittal balance]. / Etude de la fiabilité des mesures de l'incidence pelvienne dans l'analyse de l'équilibre sagittal du bassin.

PURPOSE OF THE STUDY: The pelvic incidence (PI) is an anatomic parameter independent of the spatial orientation of the pelvis. However, measuring the PI remains a technically difficult task. PI is determined from radiographic construction which has several consequences. Imperfect radiographic incidence may compromise optimal conditions for measurement. Anatomic remodeling of the sacral plate can also have an impact on rigorous measurement of the PI. Several solutions have been proposed in the literature in order to obtain equivalent measurements. The proposed methods (Duval-Beaupere, Vialle) appear logical, but remain to be validated. The purpose of this study was to determine whether the angle measured on the plain x-ray is affected by the radiographic quality of the image and to determine whether the "variant pelvic incidence" (VPI) using a reference constituted by the posterior aspect of the sacrum, can be accepted as a valid equivalent to PI in the event of anatomic remodeling. MATERIAL AND METHODS: This was a prospective study conducted in 50 patients. The PI and the VPI were measured on 3D computed tomography reconstructions which allowed three series of measurements: in a strictly lateral view, in a view with the position of the femoral heads shifted in the horizontal plane, and a view with the position of the femoral heads shifted in the vertical plane. Statistical analysis was applied to compare the three series of measures in order to search for a significant difference for the two angles under consideration (PI and VPI) dependent on the position of the pelvis. RESULTS: There was no significant difference in PI as a function of the position of the femoral heads: the coefficients of variation were all greater than 0.98 (p<0.01). For VPI, there was a significant difference between the theoretical ideal position and the horizontal shift of the femoral heads (p<0.05). Average measurements of PI and VPI were statistically different for each individual (p<0.05), with no identifiable relationship between the two values (PI and VPI). DISCUSSION: Pelvic incidence is a reliable measure, even if the quality of the x-ray is not perfect. Conversely, the variant, using the posterior aspect of the sacrum, is highly dependent on pelvic orientation, with significant differences with position. We were unable to establish a relation between PI and VPI. In practice, it would be licit to consider that the straight line between the two femoral heads indicates the center of the femoral heads. On the contrary, it would not be wise to consider the posterior aspect of the sacrum as a reliable reference.

An anthropometric study of relationships between the clival angle and craniofacial measurements in adult human skulls.

UNLABELLED: STATING BACKGROUND: The clival angle, between the ethmoidal plane and the clival plane, measures the cranial base angulation. Relations between cranial base angulation and facial patterns have been discussed and present contradictory evidence. The aim of this study is to determine whether correlations could be found between the clival angle and craniofacial measurements. METHODS: This study was carried out on a sample of 235 human skulls. Twenty landmarks were marked. The clival angle and 16 other variables were measured and compared using analysis of variance. RESULTS: Statistical analysis showed a relationship between the clival angle and six measurements (P < 0.05). There was a positive correlation between the clival angle and the cranial lengths, the nasomaxillary sagittal measurements and palatal length but the width of the foramen magnum had a negative correlation. No significant relationship was found between the clival angle and the cranial height and widths, the palatal width, the length of the foramen magnum and the mandibular measurements. CONCLUSIONS: The trends found in this study with regard to the craniofacial lengths show that the nasomaxillary complex in humans has a stable position lying beneath the anterior cranial base. Transversal, vertical and mandibular variables have a more independent relationship.

Value of fetal autopsy after medical termination of pregnancy.

We carried out a retrospective study of 352 medical terminations of pregnancy (MTP) carried out in a large French administrative region over two consecutive years. We analysed the indications for MTP and then compared the prenatal ultrasound diagnosis with fetal autopsy findings in order to demonstrate the value of pathological examination of the fetus in prenatal diagnosis and genetic counselling as well as the need to check by autopsy the quality of ultrasound screening. Preliminary analysis of the indication for these MTP showed that in 69.9% ultrasound screening had been carried out, revealing mainly brain abnormalities (22.2%) and heart defects generally associated with chromosomal abnormalities (32.1%). Prenatal findings were in agreement with autopsy results, showing no false-positive prenatal diagnoses. However, in 7.9% of cases in which brain abnormalities were detected, confirmation was not possible at autopsy because of tissue autolysis, showing the need for optimal conditions of expulsion. In 35.8% of cases, confirmation of the diagnosis by autopsy was not useful for management but still added to medical knowledge and demonstrated to the mother the reality of the defects. In 50.9%, the autopsy findings were decisive for genetic counselling.

Limits of the Lamendin method in age determination.

This study shows that epithelial attachment level, used as age determination criterion in Lamendin's method, is not reliable for adults of either sex above the age of 49 years with periodontal diseases in any quadrant. The underestimation of calculated age increases from 7 to 19 years with chronological age. On the other hand, the present paper confirms the pertinence of dentin translucency as an age indicator in Lamendin's method.

Postmortem assessment of fetal diaphyseal femoral length: validation of a radiographic methodology.

Depending on the general condition of fetal remains, forensic specialists might face difficulties concerning age estimation. Reference tables and regression equations are helpful devices in this task, although they are generally applied for complete fetuses or fetal remains including soft tissues. However, the problem of age estimation stays for osseous remains, both for entire bones and ossified parts, since most of the reference tables come from ultrasonographic measurements, which are not easily reproducible on fetal osseous remains. Furthermore, the ultrasonographic measurements contain slight errors in comparison to the real anatomical ones. This study describes a radiographic protocol and a measurement technique that facilitate and improve bone measurements, and therefore, facilitate age estimation, too. A qualitative criterion, namely a clear-cut bony endplate, was defined and tested. Its reliability (repeatability and reproducibility) turned out to be good, showing nonsignificative differences to the threshold of 0.05, with average errors of 0.26 and 0.44 mm respectively. Moreover, concerning the test of eventual size differences between the right and left femurs showed a P value < 0.0001. The test of the qualitative criterion was based on the comparison of the radiographic in situ femur measurements and the radiographic measurements of the same bones after dissection. The results were satisfactory, since an average error of 0.58 mm was obtained, which did not give any significant differences to the threshold of 0.05. It was concluded that this methodology provides an easy and precise new measurement tool for forensic practice, and can allow us to establish some nonultrasonographic tables, which fit our population.