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.

Sudden death after facial impacts: Is the brainstem involved?

Three deaths following facial impacts in the presence of witnesses and resulting in brain lesions that were visualized only on pathological examination were studied at the forensic medicine institute of Marseille. Craniofacial impacts, even of low intensity, received during brawls may be associated with brain lesions ranging from a simple knock-out to fatal injuries. In criminal cases that are brought to court, even by autopsy it is still difficult to establish a direct link between the violence of the impact and the injuries that resulted in death. During a facial impact, the head undergoes a movement of violent forced hyperextension. Death may thus be secondary to the transmission of forces to the brain, either by a mechanism involving nerve conduction that may be termed a reflex mechanism (for example by vagal hyperstimulation) or by injury to the central nervous system (axonal damage). In such situations, autopsy does not make it possible to determine the cause of death, but only to suspect it in a context of voluntary violence in the presence of witnesses, with or without violent injury observed on external examination or on superficial incisions to determine the extent of bruises or hematoma. Systemic and comprehensive investigation involving pathology and toxicology is essential in any medicolegal case for positive interpretation and discrimination of other causes of death.

Judicial handling of cases of non-accidental head trauma in infants: Review and analysis of expert assessments.

INTRODUCTION: Good practice guidelines help clinicians to establish a suspected diagnosis of non-accidental head injury (NAHI) and help forensic experts to establish a level of certainty for the diagnosis. The objective of this study was to assess how the French Health Authority (HAS) guidelines contribute to the process of producing an expert assessment, on causation and certainty in cases of suspected NAHI. METHOD: A retrospective study was conducted of the expert assessments that were conducted by a paediatric surgeon and forensic expert attached to our local court between 2002 and 2018, with the aim of determining the causal mechanism of the lesions and express a degree of certainty regarding the diagnosis. RESULTS: In our study, we found that, despite the HAS guidelines, a number of documents deemed essential for the forensic expert were sometimes missing, and that, by applying these guidelines, the decisions reached in some expert assessments could been reclassified and certain factors formerly described as risk factors for injury could be excluded. A precise dating of the traumatic event was proposed in half of cases. CONCLUSION: Our study highlights the vital role of the HAS guidelines, not only for patient management but also to ensure high-quality expert assessments. Unfortunately, guidelines were not yet being properly adhered to by medical teams.

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.

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.

Diagnosis of congenital abnormalities with post-mortem ultrasound in perinatal death.

PURPOSE: To determine the sensitivity and specificity of post-mortem ultrasound in the diagnosis of major congenital abnormalities of fetuses using conventional autopsy as the standard of reference. MATERIAL AND METHODS: All fetuses coming from terminations of pregnancy or intrauterine fetal deaths in a single institution were included. A total of 75 fetuses were included during the study period. The results of post-mortem ultrasound examinations were compared to those of conventional autopsy that served as standard of reference. RESULTS: Gestational age of the fetuses ranged from 15 to 38 weeks gestation. A complete post-mortem ultrasound assessment was possible in all fetuses. Regarding detection of brain abnormalities, post-mortem ultrasound had a sensitivity of 81.5% or 4/5 (95% CI: 63.3-91.8%), and a specificity of 97.9% (95% CI: 89.1-99.6%). Specificities for the diagnosis of thoracic, cardiac, urinary tract, spinal and bone abnormalities were 100%. CONCLUSION: Post-mortem ultrasound shows high sensitivity and specificity for the diagnosis of congenital structural abnormalities as compared to conventional autopsy, with the exception of congenital cardiac diseases.

[Vulvar lichen sclerosus in children misdiagnosed as sexual abuse]. / Lichen scléro-arophique vulvaire chez l'enfant : diagnostic différentiel d'abus sexuel.

INTRODUCTION: With the frequency of lawsuits for sexual abuse increasing, high-quality care for victims is of utmost importance. Genital examination is difficult to perform, especially on children, but is a key item for diagnosis. A case report is presented herein to illustrate this issue. CASE PRESENTATION: A sexual assault was suspected on 2.5-year-old female twins. Clinical examination primarily detected vulvar micro-hematoma and hypopigmentation, discreetly sclerosing, as well as atrophic labia and a beginning of lichenification on one of them. The other twin showed an unspecific and erythematous lesion. Elimination of the supposedly dangerous environment and a remote consultation brought out a paradoxical development to the story and confirmed the diagnosis of vulvar lichen sclerosus. DISCUSSION: Traumatic lesions caused by sexual abuse are uncommon. Coexisting allegations and lesions in the genital area lend support to the hypothesis of sexual abuse. However, genital-anal tropism dermatosis can mimic traumatic injuries. Lichen sclerosus is an example of a differential diagnosis of vulvar traumatic lesions, which is quite often unknown to physicians, including pediatricians. This case report shows that taking the appropriate time in multidisciplinary councils can suggest a differential diagnosis. Nonetheless, it should be remembered that identifying the pathology behind the lesions cannot allow the physician to negate the child's story about potentially sexual acts, although the truth of this story and the perpetrator must still be proven by a court of law.

Effect of serum on in vitro electrically mediated gene delivery and expression in mammalian cells.

In many cell systems, electric pulses can efficiently mediate gene transfer with a high level of expression in vitro. In vivo results have been reported where decrease in efficiency was obtained. The mechanisms involved in the process are unknown. Since, in vivo, the efficiency of non-viral methods of gene transfer is generally limited by the presence of serum, we report here the effect of serum on in vitro electrically mediated chinese hamster ovary cell membrane permeabilization, viability, gene transfer and expression. The results indicate that permeabilization and gene transfer are not inhibited by serum. By acting as a protector of cell viability, serum indeed increases gene transfer and expression.

In vitro delivery of drugs and other molecules to cells.

The permeability of a cell membrane can be transiently increased locally when an external electric field pulse with an overcritical intensity is applied. A position dependent modulation of the membrane potential difference is induced during the pulse. A local membrane alteration is created, which may reseal. Its molecular definition remains unknown. This phenomenon is now commonly known as electroporation or electropermeabilization. The former term implies that physical pores are created in the lipid matrix. However their existence has never been clearly demonstrated. The term electroporation is therefore rather misleading.