Discrepancies in Embryonic Staging: Towards a Gold Standard.

For over half a century, the Carnegie staging system has been used for the unification of chronology in human embryo development. Despite the system's establishment as a "universal" system, Carnegie staging reference charts display a high level of variation. To establish a clear understanding for embryologists and medical professionals, we aimed to answer the following question: does a gold standard of Carnegie staging exist, and if so, which set of proposed measures/characteristics would it include? We aimed to provide a clear overview of the variations in published Carnegie staging charts to compare and analyze these differences and propose potential explanatory factors. A review of the literature was performed, wherein 113 publications were identified and screened based on title and abstract. Twenty-six relevant titles and abstracts were assessed based on the full text. After exclusion, nine remaining publications were critically appraised. We observed consistent variations in data sets, especially regarding embryonic age, varying as large as 11 days between publications. Similarly, for embryonic length, large variations were present. These large variations are possibly attributable to sampling differences, developing technology, and differences in data collection. Based on the reviewed studies, we propose the Carnegie staging system of Prof. Hill as a gold standard amongst the available data sets in the literature.

Prevalence of Pulmonary Bullae and Blebs in Postmortem CT Imaging With Potential Implications for Diving Medicine.

BACKGROUND: Pulmonary bullae and blebs can result in a pneumothorax. Their prevalence in the normal population is currently unknown. Postmortem CT (PMCT) images from a forensic database were used to determine the prevalence of pulmonary bullae/blebs in the normal Dutch adult population and its consequence for diving medicine, as bullae and blebs are often considered a contraindication for diving. METHODS: Forensic PMCT scans of 130 adults were analyzed for the presence of bullae and/or blebs in a cross-section of the Dutch population without pulmonary disorders. The lungs had to be unharmed, expanded, and without signs of illnesses. Normal early-stage postmortem changes in the lungs were accepted. RESULTS: Analysis was performed per decade. Group I (aged 21-30 years) included 26 patients. Blebs were observed in four persons; one exhibited blebs and bullae. Group II (aged 31-40 years) included 28 patients; blebs were observed in nine individuals, one with bullae. Group III (aged 41-50 years) included 27 patients; blebs were noted in nine individuals, bullae in one, and bullae and blebs in four. Group IV (aged 51-60 years) included 28 patients; blebs were noted in seven individuals and two with bullae and blebs. Group V (aged 61-70 years) included 21 patients; blebs were noted in three persons, bullae and blebs in two, and isolated bullae in one. On average, most bullae/blebs were < 10 mm, and none exceeded 20 mm. CONCLUSIONS: By reassessing pulmonary PMCT scans, we found a surprisingly high incidence of small bullae and/or blebs in one-third (33.8%; 95% CI, 25.7-41.9) of the general population without underlying lung disease. This finding can have potential implications for diving medicine.

Postmortem radiological case series of acetabular fractures after fatal aviation accidents.

The purpose of this study was to describe radiological fracture patterns of the acetabulum sustained after fatal small aircraft aviation accidents, aiming at facilitating a better understanding of trauma mechanisms in a forensic setting. Postmortem conventional radiographs or CT scans of 29 victims of 20 small aircraft aviation accidents were analyzed for skeletal acetabular trauma. Among the 29 fatalities (27 males and 2 females, median age 55 years (range: 21-76 years)), 20 victims had pelvic fractures (69%), of which 19 victims (66%) had one or more acetabular fractures. Bilateral acetabular fractures occurred in 11 victims. When considering left and right acetabula in each victim as separate entities, 38 of the 58 acetabula included in this case series exhibited one or more fractures. Both the anterior and posterior acetabular columns were fractured in 28 acetabula. Acetabular fractures were frequently encountered in this series of 29 victims of small fatal aircraft accidents. Fractures of the acetabulum occur from ventrally directed impact (i.e. to the knee) or laterally directed impact (i.e. to the greater trochanter of the femur). Radiological descriptions of the fracture patterns can therefore aid in the forensic analysis of the mechanism of trauma in aviation accidents. Postmortem multi-slice CT scan images are preferrable in the assessment of acetabular fractures.