Fracture patterns of the hyoid-larynx complex after fatal trauma on the neck: retrospective radiological postmortem analysis of 284 cases.

PURPOSE: Fatal trauma on the neck occurs frequent in forensic cases and often results in fractures of the hyoid-larynx complex. The aim of the present study is to provide an overview of fractures in the hyoid-larynx complex that occur due to fatal trauma on the neck and can be observed by radiological evaluation. METHODS: Radiological images from a forensic radiological database created in -BLINDED- were used for analysis. Hyoid-larynx complexes were explanted in 284 individuals who accordingly to the forensic pathologist allegedly died from fatal trauma on the neck. These explants were imaged with conventional X-rays in eight directions and a CT scan. Radiological images were analyzed for fractures, dislocations, joints, and anatomical variations by a trained analyst and a radiologist. RESULTS: In 281/284 cases, the hyoid bone and, in 252/284 cases, the thyroid cartilage could be assessed. In 56 victims (20%), the hyoid bone was fractured, 55 times in the greater horn, 1 fracture in the body. The calcified superior horn of the thyroid showed a fracture in 101 victims (40%). The calcified cricoid cartilage was fractured in one case. Multiple fractures were found in 31/284 cases (11%). Joints between the greater horn and body of the hyoid were present in 74%. CONCLUSION: Trauma on the neck leads most frequently to fractures of the superior horn of the thyroid cartilage and second most to fractures in the greater horn of the hyoid bone. (Forensic) radiologists should be aware of uncommon fracture locations, anatomical variations, and dislocations in the hyoid-larynx complex.

Massive gas embolisms in diving fatalities visualized by radiology and neuropathology.

Massive vascular gas embolism is a feared and often lethal symptom of decompression illness, resulting from diving accidents. The aim of this case report was to correlate post-mortem computed tomography scan (PMCT) findings with autopsy in cases of massive vascular gas embolism. Two cases of fatal diving accidents were retrospectively selected from a forensic radiological pathological database. The PMCT results were initially shared with the forensic pathologist prior to autopsy, enabling a more accurate overall assessment. Both cases were in retrospect thoroughly studied to compare the PMCT findings with the autopsy results. In general, intra- and extra-vascular gas collections are easily detected on PMCT in all body regions. We focused on abundant intravascular gas collections, mainly in the large brain vessels. General autopsy findings are described in both cases, and in one case we elaborate on specific intracerebral changes found at autopsy. Both cases were diagnosed as pulmonary barotrauma with subsequent vascular gas embolisms. We conclude that PMCT excels in the detection of macroscopic gas collections in the body, whereas microscopic gas collections identified at autopsy aid in the differentiation between decompression sickness and pulmonary barotrauma followed by vascular gas embolism. The presented cases highlight the advantages of using both PMCT and autopsy in the post-mortem evaluation of fatal diving accidents.

The value of post-mortem computed tomography of burned victims in a forensic setting.

OBJECTIVES: Fire deaths are challenging fatalities for forensic pathologists, as the main question of whether death was due to the fire or not needs to be answered. In this retrospective study, we assessed whether post-mortem computed tomography (PMCT) has an added value prior to a forensic autopsy of burned victims. METHODS: From 2008 to 2016, a PMCT was performed in 50 burned corpses prior to a complete forensic autopsy. In retrospect, all 50 PMCT scans were systematically assessed by a forensically experienced radiologist, masked from the autopsy reports. Subsequently, the PMCT findings were compared with the autopsy reports. RESULTS: Heat fractures, contractions and destruction of extremities, subcutaneous emphysema and post-mortem gas collections were easier to detect by PMCT compared to autopsy. Alterations by penetrating and blunt trauma and the presence of foreign bodies were easy to detect by PMCT as well by autopsy. PMCT was, however, not successful in detecting signs of vitality during the fire, detection of superficial thermal injuries and to answer the main question of the forensic autopsy, which is to investigate the cause of death. CONCLUSIONS: PMCT prior to autopsy is a valuable add-on in the post-mortem forensic investigation of burned victims for detection of hidden signs of trauma, gas collections and foreign bodies. However, since PMCT cannot answer the two main questions in forensic examination-determining the cause of death and detecting signs of vitality during the fire-it cannot replace an autopsy. KEY POINTS: • Post-mortem CT (PMCT) in burned victims shows hidden signs of trauma. • Foreign bodies and gas collections can easily be detected. • Cause of death and vitality signs cannot be assessed by PMCT.

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.

Correction to: Fracture patterns of the hyoid-larynx complex after fatal trauma on the neck: retrospective radiological postmortem analysis of 284 cases.

PURPOSE: Fatal trauma on the neck occurs frequent in forensic cases and often results in fractures of the hyoid-larynx complex. The aim of the present study is to provide an overview of fractures in the hyoid-larynx complex that occur due to fatal trauma on the neck and can be observed by radiological evaluation. METHODS: Radiological images from a forensic radiological database created in the Groene Hart Hospital, Gouda, the Netherlands were used for analysis. Hyoid-larynx complexes were explanted in 284 individuals who accordingly to the forensic pathologist allegedly died from fatal trauma on the neck. These explants were imaged with conventional X-rays in eight directions and a CT scan. Radiological images were analyzed for fractures, dislocations, joints, and anatomical variations by a trained analyst and a radiologist. RESULTS: In 281/284 cases, the hyoid bone and, in 252/284 cases, the thyroid cartilage could be assessed. In 56 victims (20%), the hyoid bone was fractured, 55 times in the greater horn, 1 fracture in the body. The calcified superior horn of the thyroid showed a fracture in 101 victims (40%). The calcified cricoid cartilage was fractured in one case. Multiple fractures were found in 31/284 cases (11%). Joints between the greater horn and body of the hyoid were present in 74%. CONCLUSION: Trauma on the neck leads most frequently to fractures of the superior horn of the thyroid cartilage and second most to fractures in the greater horn of the hyoid bone. (Forensic) radiologists should be aware of uncommon fracture locations, anatomical variations, and dislocations in the hyoid-larynx complex.

The radiodensity of cerebrospinal fluid and vitreous humor as indicator of the time since death.

PURPOSE: After death, a series of changes occur naturally in the human body in a fairly regular pattern. These postmortem changes are detectable on postmortem CT scans (PMCT) and may be useful in estimating the postmortem interval (PMI). The purpose of our study is to correlate the PMCT radiodensities of the cerebrospinal fluid (CSF) and vitreous humor (VH) to the PMI. METHODS: Three patient groups were included: group A consisted of 5 donated cadavers, group B, 100 in-hospital deceased patients, and group C, 12 out-of-hospital forensic cadavers. Group A were scanned every hour for a maximum of 36 h postmortem, and the tympanic temperature was measured prior to each scan. Groups B and C were scanned once after death (PMI range 0.2-63.8 h). Radiodensities of the VH and CSF were measured in Hounsfield units. Correlation between density and PMI was determined using linear regression and the influence of temperature was assessed by a multivariate regression model. Results from group A were validated in groups B and C. RESULTS: Group A showed increasing radiodensity of the CSF and VH over time (r (2) CSF, 0.65). PMI overruled the influence of temperature (r = 0.99 and p = 0.000). Groups B and C showed more diversity, with CSF and VH radiodensities below the mean regression line of Group A. The formula of this upper limit indicated the maximum PMI and was correct for >95 % of the cadavers. CONCLUSION: The results of group A showed a significant correlation between CSF radiodensity and PMI. The radiodensities in groups B and C were higher than in group A, therefore the maximum PMI can be estimated with the upper 95 % confidence interval of the correlation line of group A.

Radiological analysis of hand and foot injuries after small aircraft crashes.

Medico-legal investigation of fatal aviation accidents should contribute to the reconstruction of the accident in addition to providing the usual information about cause and manner of death. In cases with more than one fatality, the question of who was flying the plane at the time of the crash may need to be answered. In such cases the identification of "control injuries" plays an important role. This study aims to investigate whether specific patterns of skeletal hand and foot injuries could assist in the identification of the pilot. The analysis of radiological investigations of hands and feet of 27 fatalities from 18 accidents showed that foot injuries are more frequent than hand injuries in pilots and passengers, dislocations of feet were more frequent in passengers, and right-sided injuries were more frequent in pilots. Injuries of the distal parts of the hand were slightly more frequent in the pilot group. The limited numbers in the study do not allow definitive conclusions and further investigations are needed. However, the study yields interesting results and shows that radiological examination should be included in the medico-legal air crash investigation.

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.

Variants of the hyoid-larynx complex, with implications for forensic science and consequence for the diagnosis of Eagle's syndrome.

Thorough anatomic knowledge of the hyoid-larynx complex is necessary for forensic radiologists and ear-nose-throat surgeons, given the many anatomic variations that originate in embryology. In forensics the anomalies must be distinguished from fractures because the latter are indicative of violence on the neck. In this manuscript we describe the anatomical variations that can be found in the hyoid-larynx complex and explain their etiology. 284 radiological scans of excised hyoid-larynx complexes were examined with X-ray and CT. Some rare cases from literature and historical collections were added. Two third of the examined hyoid-larynx complexes deviated from the anatomical standard and showed uni- or bilateral ankylosis in the hyoid bone and/or so-called triticeal cartilages. In one fifth of the cases we found striking anatomical variants, mostly derived from the cartilage of the second pharyngeal arch. Anatomical variations of the hyoid-larynx complex can be explained by embryological development. The aberrant hyoid apparatus and the elongated styloid processes (Eagle syndrome) should be considered as one clinical entity with two different expressions as both anomalies are derived from the cartilage of the second pharyngeal arch. Several variants can mimic fractures in this region, so our study is important for radiologists and forensic experts assessing cases of possible violence on the neck.

The development of the human hyoid-larynx complex revisited.

OBJECTIVES/HYPOTHESIS: The hyoid-larynx complex is highly prone to anatomical variation. The etiology of anatomical variants such as Eagle's syndrome and the aberrant hyoid apparatus can be explained from embryonic development. Modern textbooks state that the hyoid bone body develops from the second and third pharyngeal arch cartilages, and that thyroid cartilage derives from the fourth and sixth arch cartilages. This description, however, is incompatible with various anatomical variants, and it is unclear whether it was based on observations in human embryos or on comparative embryology. STUDY DESIGN: 14 human embryos from the Carnegie collection between Carnegie stage 17 and 23 (42-60 days) were selected based on their histological quality. METHODS: Histological sections of the selected embryos were examined. Three-dimensional models were prepared in an interactive format. These anatomical models provide crucial spatial information and facilitate interpretation. RESULTS: We observed a less-complicated development of the hyoid-larynx complex than is currently described in textbooks. The body of the hyoid bone originates from a single growth center, without overt contributions from second and third pharyngeal arch cartilages. The fourth and sixth arch cartilages were not detected in human embryos; the thyroid and cricoid cartilages develop as mesenchymal condensations in the neck region. CONCLUSIONS: Despite new research techniques, theories about hyoid-larynx complex development from the beginning of the 20th century have not been refuted properly and can still be found in modern literature. Based on observations in human embryos, we propose a new and relatively simple description of the development of the hyoid-larynx complex to facilitate better understanding of the etiology of anatomical variants. LEVEL OF EVIDENCE: NA Laryngoscope, 1829-1834, 2018.

The vanishing duodenal polyp: mesenteric invagination presenting as duodenal pseudopolyp.

Duodenal polypoid masses are an uncommon finding mainly diagnosed incidentally at endoscopy or surgery. We report a 39-year-old female patient with symptoms of intermittent stabbing pain in the upper right abdominal quadrant and an iron deficiency anaemia, without complaints of weight loss, haematemesis or melaena. A duodenal polyp and acute duodenitis have been described during endoscopic examinations and CT and ultrasound. Surgical excision of the polyp was advised. Intraoperatively, an elongated duodenum was remarkable; however, at duodenotomy, no polyp was found, nor during intraoperative endoscopy. Looking back at the endoscopy and imaging results, it was noted that the polyp varied in size and location. It was therefore concluded that we dealt with the pseudopolyp phenomenon, caused by invagination of the duodenal wall and its mesentery into the duodenum, presenting as a lipomatous pseudopolyp. Telescopic invagination of the duodenal wall was facilitated by the elongated hypermobile duodenum.