An automated landmark method to describe geometric changes in the human mandible during growth.

OBJECTIVE: The principal aim of this study was to assess an automatic landmarking approach to human mandibles based on the atlas method. The secondary aim was to identify the areas of greatest variation in the mandibles of middle-aged to older adults. DESIGN: Our sample consisted of 160 mandibles from computed tomography scans of 80 men and 80 women aged between 40 and 79 years. Eleven anatomical landmarks were placed manually on mandibles. The automated landmarking through point cloud alignment and correspondence (ALPACA) method implemented in 3D Slicer was used to automatically place landmarks to all meshes. Euclidean distances, normalized centroid size, and Procrustes ANOVA were calculated for both methods. A pseudo-landmarks approach was followed using ALPACA to identify areas of changes among our sample. RESULTS: The ALPACA method showed significant differences in Euclidean distances for all landmarks compared to the manual method. A mean Euclidean distance of 1.7 mm was found for the ALPACA method and 0.99 mm for the manual method. Both methods found that sex, age, and size had a significant effect on mandibular shape. The greatest variations were observed in the condyle, ramus, and symphysis regions. CONCLUSION: The results obtained using the ALPACA method are acceptable and promising. This approach can automatically place landmarks with an average accuracy of less than 2 mm, which may be sufficient in most anthropometric analyses. In the light of our results, however, odontological application such as occlusal analysis is not recommended.

Root and canal morphology of the permanent teeth in medieval and current French population.

OBJECTIVE: This work describes and compares the root and root canal morphology of a medieval population dating from the 8th to 10th century from the southwest of France, and a current French population. DESIGN: The root morphology of 579 teeth from 70 medieval individuals was analyzed using cone beam computed tomography, and compared with 690 teeth from a current French population of 329 individuals. The Vertucci classification was used to describe the root canal configuration. RESULTS: In the medieval population, the maxillary first premolar usually had one root. In contrast, in the current population this tooth predominantly had two roots, and the three-root form had appeared. Mandibular canine with two roots was observed in 5.7% of cases, and in the current population this form was found in 1.6% but the difference was not significative. The greatest variability between the two populations in terms of root canal configuration was in one-rooted maxillary first and second premolars, the mandibular canines, and the distal roots of the mandibular first molars. Differences in root numbers and canal configurations of the maxillary molars investigated among the two populations were not significant. CONCLUSIONS: This study indicated that the upper first premolar of the current population tended to have more than one root, while this tooth type of the medieval group mostly appeared with only one. For the root canal configuration, studies in the upper premolars, lower canines and first molars of the current population apparently revealed a significant simplification compared with the ancient group.

[Damage repair in breast cancer has to evolve]. / Évaluation du dommage corporel en sénologie : une nécessaire évolution.

Breast damage is likely to result in compensation according to the principle of full compensation. However, breast damage, little covered in the scales usually used, requires a specific methodology. The quantification of functional prejudice must be done with regard to the age of the victim and must take into account the possible repercussions on mobility (shoulder and/or spine) as well as the psychological repercussions. Whether or not the nipple and areola are preserved should be described. Temporary aesthetic damage (before breast reconstruction) must be assessed on the basis of objective elements, its duration and quantification on a scale of 0 to 7. Permanent aesthetic damage takes into account scars, deformities, amputations and quality of the prosthesis. A new scale for evaluating permanent aesthetic damage is proposed. Sexual prejudice must take into account an impairment of the pleasure related to sexuality and its erotic function, in line with the concept of sexual health. However, even after reconstruction, the areas of quality of sexual life and sexual satisfaction often remain affected. An exploration using standardized questions from validated questionnaires such as BREAST-Q can be useful. The sequelae linked to the damage on a breast can also lead the woman to limit certain pleasure activities, in particular because of psychological discomfort or even be the cause of a loss of opportunity to carry out a family's life plan.

Three-dimensional analysis of bitemarks: A validation study using an intraoral scanner.

Conservation of the three-dimensional aspect of bitemarks optimizes their analysis. Although bitemarks could be recorded with a surface scanner, in clinical dentistry, intraoral scanners are used as an alternative to conventional dental impressions. Here we assess the reproducibility and the reliability of a three-dimensional bitemark analysis protocol using an intraoral scanner. Twenty-seven volunteers bit on different materials: dental wax, hard cheese, chocolate and apple. Then, bitemarks and dentitions were scanned with the PlanMeca® Emerald intraoral scanner and the scans obtained were exported into the mesh comparison software, CloudCompare®, which can generate overlays automatically. For this purpose, dentitions were aligned and compared with the indentations. The meshing and non-meshing areas were visualized using a colorimetric scale. First, the same blinded observer compared the bitten materials by analyzing 256 meshing areas for each. Secondly, comparisons of bitemarks from wax were analyzed in a randomized blinded study involving four observers (dentist, dental student, forensic scientist and police officer) and predictive values were calculated. The wax support obtained the best result and apple the worst. The rate of correct classifications was high and misclassification was rare. For the all observers, negative predictive values were near 100%. Positive predictive values were more variable. Moreover, the work clearly highlighted the importance of experience in odontology.

Sharp bone trauma diagnosis: a validation study using epifluorescence microscopy.

Identifying tool mark and involved weapon in sharp force trauma is essential to understanding the circumstances of death. But accuracy and reliability of such expert testimony remains unknown, and validation studies are rare in forensic literature. That is why, we conducted an experiment in order to determine error rates and predictive values on identifying the right implement through different types of knife-inflicted trauma. Human bone cut marks were analysed through epifluorescence microscopy. The samples were examined through a randomised, blinded, controlled study by three researchers with varying degrees of experience with direct and indirect observation of cut marks (photography). Our results showed that identifying the weapon involved is possible thanks to numerous criteria analysis. Correct classification rates were high and misclassifications rare. Asymmetric blades obtained better results than symmetric blades. Predictive values were also calculated, and the negative one reached very high levels, near 100% with regard to all the implements. Positive predictive values were more variable. But even if individual diagnoses remain in doubt, triage can be done and tools not implicated in injury can be eliminated with certainty. Moreover, our work clearly highlighted the importance of experience in such activities. A high level of experience is fundamental to obtain the best values, especially in such a context where evidence reliability is extremely important for forensic admissibility testimony in the court.

Towards multi-phase postmortem CT angiography in children: a study on a porcine model.

PURPOSE: Multi-phase postmortem computed tomography angiography (MPMCTA) is a growing technique, which is standardized for adults. Application of this protocol for a children population is not so well defined. Our study aims to adapt the adult's protocol to children, using a porcine model. MATERIAL AND METHODS: Three groups of 18 pigs were studied, with a weight distribution between 4 and 48 kg. Different pump devices were used. Pigs of group I were studied using the Virtangio® machine, whereas pigs of groups II and III were studied using used the Medrad® machine. Study of vascular opacification was possible using a semi-quantitative method based on 26 arterial and 26 venous segments that were distributed over the entire body from the cephalic extremity to the posterior pawns. RESULTS: While thoracic, abdominal, and pelvic vascular opacification were complete for each individual pig in a group, group III showed better vascular opacification for the cephalic extremity. This was also true for anterior and posterior pawns vascular opacification. Spearman correlation tests showed a significant relationship between anthropometric characteristics of pigs, injection parameters, and percentage of opacified segments. A higher percentage of opacification was obtained for individuals of lower weights, with comparatively lower quantities of contrast agent injected. CONCLUSION: Postmortem computed tomography angiography (PMCTA) was possible for all the individuals, particularly for small weights (4 kg) using the Medrad® machine. However, further studies are needed to better understand the procedure.

Old hearts for modern investigations: CT and MR for archaeological human hearts remains.

INTRODUCTION: Among 800 burials dated between the 15th and 18th centuries and found in the center of Rennes (Brittany, France), a collection of five heart-shaped lead urns was discovered. This material was studied using classical methods (external study, autopsy and histology), and also modern imaging like computed tomography (CT), magnetic resonance (MR) before and after coronary opacification. The aim of this manuscript is to describe different steps of ancient soft tissues study, especially using imaging techniques. METHODS: The study gathered various specialists: anthropologists, archeologists, forensic pathologists, radiologists, pathologic physicians, and physicists. Imaging techniques were performed, before and after coronary opacification. Finally, hearts were autopsied and different histological samples were analyzed. RESULTS: Only heart n°2 was too damaged to be studied. Heart n°3 was considered as normal using all investigation techniques. The study of Hearts n°s 4 and 5 revealed dilated cardiomyopathy while Heart n°1 showed important signs of diffuse hypertrophic cardiomyopathy. Different fibro lipid plaques were identified using imaging techniques, and were confirmed by histology. CONCLUSIONS: The study of archeological soft tissues using modern imaging is possible if the material is well-preserved. This type of research can uncover principal findings, allowing scientists to establish diseases of ancient times.

[Complications after laser hair removal: the standpoint of a dermatological legal expert regarding liability]. / Accidents secondaires aux actes de photoépilation : la pratique d'un expert de justice dermatologue en matière de responsabilité

BACKGROUND: Laser hair removal is widely used, including outside medical settings. Potential complications, notably burns, may engage the operator's liability. In this case, investigations by medical experts are frequently requested. PATIENTS AND METHODS: We describe 6 expert examinations carried out by the same legal dermatology expert between 2012 and 2014. They concerned burns of varying severity caused by laser hair removal procedures carried out by a doctor, a physiotherapist and 4 beauticians. DISCUSSION: Laser hair removal is carried out in many beauty centres, although in France it is restricted by law to medical use. This practice is thus currently the subject of legal and economic controversy. The analysis of 6 medical expert investigations of accidents involving laser hair removal illustrates the various types of fault in which the operator's liability may be engaged and it also serves to redefine the legal framework of this act within the realm of aesthetic medicine.

Diagnostic value of high-resolution peripheral quantitative computed tomography (HR-pQCT) in the qualitative assessment of cribra orbitalia: a preliminary study.

Cribra orbitalia are a porotic or sieve-like lesions in the bony orbital roof. This characteristic has frequently been detected in palaeopathological skulls from many parts of the world and has been the object of extensive research. Our objective was to determine if high-resolution peripheral quantitative computed tomography (HR-pQCT) could produce reliable information in the study of cribra orbitalia. Seven skulls displaying cribra orbitalia were investigated by HR-pQCT. The two-dimensional slices were compared with histological sections. The HR-pQCT images and histological sections showed similar results, i.e. two groups of lesions with different characteristics. HR-pQCT can be of great value in palaeopathological research. It is a nondestructive, fast and precise technique that allows an easy evaluation of the bone architecture without destruction of the sample.

[Practical guide to the examination and interpretation of genital lesions of minor female victims of sexual assault]. / Victimes féminines mineures d'agressions sexuelles : guide pratique pour l'examen et l'interprétation des lésions génitales.

Through a comprehensive review of the literature on sexual assault, the authors propose to clarify the different stages of the exam and help the practitioner to the forensic interpretation of lesions. The authors describe the basic principles that make consensus in how to interview victims in order to increase the reliability of the information collected. The various medical data that must be collected allowing to guide diagnosis (urogenital symptoms, sexual behaviour disorder) or facilitate the interpretation of lesions (age of puberty, use of tampons…) are specified as well as the different positions of examination and their association to other complementary techniques (Foley catheter, colposcopy, toluidine blue). The authors present a simple decision tree that can help the practitioner to interpret the laceration of the hymen. They detail the description and forensic interpretation of all genital lesions that may be encountered as a result of sexual assault, and the pitfalls to avoid. Finally, two main problems in the interpretation of lesions are described, the absence of injury after penetration and the accidental genital lesions.

The usefulness of post-mortem CT angiography in injuries caused by falling from considerable heights: three fatal cases.

OBJECTIVE: Post-mortem computed tomography is a diagnostic tool forming part of the arsenal available to forensic pathologists today. In addition to its usefulness in detecting bone lesions, which has long been recognized, this technique has nowadays been enhanced by the development of CT angiography. The role of multiphase post-mortem computed tomography angiography (multiphase PMCTA) is primordial, improving detection of solid organ lesions and permitting vascular lesions to be visualized directly. MATERIAL AND METHODS: Our paper presents a series of three deaths by falling from a considerable height recorded since the beginning of 2012. We report the usefulness of PMCTA and the various mechanisms involved in the trauma. RESULTS: Most of the lesions were diagnosed by both PMCTA and autopsy, including the rare lesions, but the peripheral bone lesions and the hemopneumatocele were diagnosed only by PMCTA, while dislocation of vertebrae and the testicular fractures were detected solely by autopsy. CONCLUSION: PMCTA is a new, minimally-invasive technique which, combined with autopsy, provides better visualization and detection of certain lesions, particularly in the case of death by falling from a great height.

Virtual anthropology and forensic identification using multidetector CT.

Virtual anthropology is made possible by modern cross-sectional imaging. Multislice CT (MSCT) can be used for comparative bone and dental identification, reconstructive identification and lesion identification. Comparative identification, the comparison of ante- and post-mortem imaging data, can be performed on both teeth and bones. Reconstructive identification, a considerable challenge for the radiologist, identifies the deceased by determining sex, geographical origin, stature and age at death. Lesion identification combines virtual autopsy and virtual anthropology. MSCT can be useful in palaeopathology, seeking arthropathy, infection, oral pathology, trauma, tumours, haematological disorders, stress indicators or occupational stress in bones and teeth. We examine some of the possibilities offered by this new radiological subspeciality that adds a new dimension to the work of the forensic radiologist. A multidisciplinary approach is crucial and involves communication and data exchange between radiologists, forensic pathologists, anthropologists and radiographers.

Diagnosis of drowning using post-mortem computed tomography - state of the art.

AIM OF THE STUDY: Recent studies using post-mortem computed tomography (PMCT) have suggested this imaging modality is of value in the positive diagnosis of drowning. We summarize the data from the literature regarding the diagnostic value of CT in cases of drowning. MATERIAL AND METHODS: We performed an all-language search of literature published from 1999 to 2013 with the key words "post-mortem CT scan", "drowning and CT scan", "near-drowning diagnosis", and "drowning diagnosis". RESULTS: Only 11 articles, whose data enabled complementary statistical analysis, were included. The presence of fluid and sediment in paranasal sinuses appear to be the determinants of the diagnosis of drowning. The presence of fluid in the sinuses had a sensitivity of 100%, and of 90% in the trachea and main bronchi. The results were completed by the high specificity of the presence of sediment in the paranasal sinuses, upper airways and stomach, which was 100% for all three. Haemodilution was present in cases of drowning (p < 0.001). The values made it possible to formulate a decision algorithm for the diagnosis of drowning.

Philemon and Baucis syndrome: three additional cases of double deaths of married couples.

The simultaneous death of two people is immediately considered as a suspect. However, this feeling is reinforced when the individuals are spouses. In these situations, criminal and forensic investigations are required to establish whether or not the deaths were homicidal in nature. Despite many descriptions of simultaneous deaths being present in the literature, the simultaneous death of two spouses from natural causes is poorly described with Ciesiolka et al., Department of Legal Medicine in Gießen (Germany), being the only ones to have reviewed two case reports involving these circumstances. The scarcity of this type of information in the literature renders the task of claiming natural simultaneous death as the final outcome of an investigation difficult. We would like to report three additional cases with the aim of better describing this type of event. In all three cases, the bodies were those of a married couple in their 80s. The bodies were discovered in the same room. In each case, the death of one of the spouses could be attributed to natural cause; however the death of the other spouse could not be determined with certainty, and shared several similarities in all cases: simultaneity in death; a pre existing cardiovascular disease/disorder; a certain degree of fragility and dependence on the other spouse whose death could lead to acute psychological stress. Intense psychological disorder could trigger acute coronary or rhythmic disorders. The mechanisms by which brain activity influences cardiac electrophysiology are now known to take place via the autonomic nervous system mediation. This brain activity could provide an explanation for the death of the individuals with pre-existing heart conditions, who underwent significant stress upon occurrence of the death of their partners. The death of these individuals, which took place at the same place and time as their deceased spouses, can be attributed to natural causes: the Philemon and Baucis syndrome.

Effect of voxel size on the accuracy of 3D reconstructions with cone beam CT.

OBJECTIVES: The various types of cone beam CT (CBCT) differ in several technical characteristics, notably their spatial resolution, which is defined by the acquisition voxel size. However, data are still lacking on the effects of voxel size on the metric accuracy of three-dimensional (3D) reconstructions. This study was designed to assess the effect of isotropic voxel size on the 3D reconstruction accuracy and reproducibility of CBCT data. METHODS: The study sample comprised 70 teeth (from the Institut d'Anatomie Normale, Strasbourg, France). The teeth were scanned with a KODAK 9500 3D® CBCT (Carestream Health, Inc., Marne-la-Vallée, France), which has two voxel sizes: 200 µm (CBCT 200 µm group) and 300 µm (CBCT 300 µm group). These teeth had also been scanned with the KODAK 9000 3D® CBCT (Carestream Health, Inc.) (CBCT 76 µm group) and the SCANCO Medical micro-CT XtremeCT (SCANCO Medical, Brüttisellen, Switzerland) (micro-CT 41 µm group) considered as references. After semi-automatic segmentation with AMIRA® software (Visualization Sciences Group, Burlington, MA), tooth volumetric measurements were obtained. RESULTS: The Bland-Altman method showed no difference in tooth volumes despite a slight underestimation for the CBCT 200 µm and 300 µm groups compared with the two reference groups. The underestimation was statistically significant for the volumetric measurements of the CBCT 300 µm group relative to the two reference groups (Passing-Bablok method). CONCLUSIONS: CBCT is not only a tool that helps in diagnosis and detection but it has the complementary advantage of being a measuring instrument, the accuracy of which appears connected to the size of the voxels. Future applications of such measurements with CBCT are discussed.

Cone-Beam Computed Tomography: a useful tool for dental age estimation?

Assessment of oral hard tissues can be of great help in determining the age of an individual. The development and physiological aging of teeth provide many clues for estimating age, in methods that are mainly based on conventional radiography. Although these conventional techniques reveal information on the anatomical and pathological characteristics, they only show two-dimensional images of a system that originally exists in three dimensions. With the growth and development of three-dimensional imaging, it has become possible to include measurements such as volumetric data, which give a better grasp of the continuous process of tooth mineralization. Up to now, these measurements have been obtained in vitro using micro-computed tomography (micro-CT) but three-dimensional imaging has recently been enriched by a new technique: Cone-Beam Computed Tomography (CBCT), which is devoted to the maxillo-facial sphere. These acquisitions may offer real potential for exploiting and analyzing volumetric measurements of teeth. We hypothesize that, using CBCT acquisitions, multiple regression analysis including quantitative volumetric measurement of various parts of each tooth can be useful to determine significant variables for dental age estimation in living subjects. Currently, CBCT examinations are being performed and contain important information for the quantitative study of dental tissue. Although CBCT examinations are conducted in the first intention of making a clinical diagnosis or prognostic evaluation, they could be used as an initial database for the measurement of dental volumes and their ratios, thus furnishing preliminary evaluations and information. Multiple regression analysis requires the constitution of a larger sample sizes which may demonstrate that CBCT data can be helpful to study other aspects of dental morphology in greater depth, especially dental growth. In this hypothesis, integration with a larger network system would be necessary. CBCT data could be helpful in defining new parameters for the rating of dental development, for a quantitative description of the fractions of crown and root and could offer new research oriented towards various aspects of teeth and jaws, thanks to its broad sampling possibilities.

Accuracy of 3D reconstructions based on cone beam computed tomography.

Three-dimensional imaging of teeth will increase its impact in clinical practice if reconstructions are metrically accurate. We hypothesized that, with cone beam computed tomography (CBCT) data, three-dimensional images of teeth can be reconstructed with the same accuracy and precision as with in vitro micro-computed tomography (micro-CT) data acquisition, the current reference standard. We used a sample of CBCT and micro-CT data taken of tooth germs. Volumes obtained with CBCT and micro-CT devices were statistically similar (n = 120, Passing-Bablok regression). Geometric deviations between CBCT and micro-CT three-dimensional surface reconstructions did not show any areas of important and systematic errors. Future investigations with the use of larger samples may also demonstrate that CBCT data will be helpful for a more in-depth study of other aspects of dental morphology--for example, assessing tooth development. With sufficient accuracy for clinical situations, potential future medical applications of such measurements with CBCT are envisaged.

Prisoners and skin diseases in Toulouse, France: epidemiological analysis and evaluation of life impact.

BACKGROUND: Dermatology in a penitentiary environment is an under-researched field. OBJECTIVES: To study the prison population seeking medical advice for skin diseases and to assess among detainees the life impact of these diseases, an approach that to the best of our knowledge has not previously been reported. METHODS: This prospective study was carried out in the male population of two penal institutions in the region of Toulouse, south-western France. RESULTS: One hundred seventy-eight men were seen, for a total of 234 diagnoses and 281 consultations. The five most frequent diagnoses, in order of decreasing frequency, were disorders of the pilosebaceous follicle, fungal diseases, benign skin tumours, warts and eczemas, which are common skin diseases. However, 72% of inmates believed their skin disease was directly related to detention. This belief was related to the conditions of life in prison (seclusion and its effects) and to frequent psychological problems. CONCLUSIONS: The disorders observed were generally benign skin conditions that could be expected in a population of young men living in a closed community. They led to a high demand for care and treatment: skin diseases represented the largest specialist consultation in our institutions. Skin problems can easily be managed in an outpatient unit, which confirms the usefulness of a dedicated dermatology clinic within the outpatient consultation units of penal institutions in order to provide care of equivalent quality to that available in a free environment. The dermatologist can have an important role in the medical management and the health education of prisoners.