Age estimation by evaluating median palatine suture closure using postmortem CT.

This study sought to develop an age-estimation formula to evaluate the extent of median palatine suture (MP) closure using postmortem computed tomographic (PMCT) images. The PMCT images of 634 Japanese subjects (mean age, 54.5 years; standard deviation [SD], 23.2 years) with known age and sex were examined. The degree of suture closure of the MP, anterior median palatine suture (AMP), and posterior median palatine suture (PMP) was measured and scored (suture closure score, SCS), and a single linear regression analysis was conducted with age at death. On the analysis, SCS of MP, AMP, and PMP showed a significant correlation with age (p < 0.001). The correlation coefficient of MP was higher (0.760, male; 0.803, female; and 0.779, total) than that of AMP (0.726, male; 0.745, female; and 0.735, total) or PMP (0.457, male; 0.630, female; and 0.549, total). The regression formula and standard error of estimation (SEE) of MP were calculated as Age = 100.95 × SCS + 20.51 (SEE 14.87 years) for male subjects, Age = 91.93 × SCS + 26.65 (SEE 14.12 years) for female subjects, and Age = 95.17 × SCS + 24.09 (SEE 14.59 years) for the total, respectively. In addition, another 50 Japanese subjects were randomly selected to validate the age-estimation formula. In this validation, the actual age of 36 subjects (72%) was within the estimated age ± SEE. This study showed that the age estimation formula using PMCT images of MPs was potentially useful for estimating the age of unidentified corpses.

Stature estimation by semi-automatic measurements of 3D CT images of the femur.

Stature estimation is one of the most basic and important methods of personal identification. The long bones of the limbs provide the most accurate stature estimation, with the femur being one of the most useful. In all the previously reported methods of stature estimation using computed tomography (CT) images of the femur, laborious manual measurement was necessary. A semi-automatic bone measuring method can simplify this process, so we firstly reported a stature estimation process using semi-automatic bone measurement software equipped with artificial intelligence. Multiple measurements of femurs of adult Japanese cadavers were performed using automatic three-dimensional reconstructed CT images of femurs. After manually setting four points on the femur, an automatic measurement was acquired. The relationships between stature and five femoral measurements, with acceptable intraobserver and interobserver errors, were analyzed with single regression analysis using the standard error of the estimate (SEE) and the coefficient of determination (R2). The maximum length of the femur (MLF) provided the lowest SEE and the highest R2; the SEE and R2 in all cadavers, males and females, respectively, were 3.913 cm (R2 = 0.842), 3.664 cm (R2 = 0.705), and 3.456 cm (R2 = 0.686) for MLF on the right femur, and 3.837 cm (R2 = 0.848), 3.667 cm (R2 = 0.705), and 3.384 cm (R2 = 0.699) for MLF on the left femur. These results were non-inferior to those of previous reports regarding stature estimation using the MLF. Stature estimation with this simple and time-saving method would be useful in forensic medical practice.

Age estimation by evaluation of osteophytes in thoracic and lumbar vertebrae using postmortem CT images in a modern Japanese population.

Estimation of age at death is important in forensic investigations of unknown remains. There have been several reports on applying the degree of osteophyte formation-an age-related change in the vertebral body-for age estimation; however, this method is not yet established. This study investigated a method for age estimation of modern Japanese individuals using osteophytes measured on CT images. The sample included 250 cadavers (125 males) aged 20-95 years. The degree of osteophyte formation was evaluated as score O (0-5 points), and the degree of fusion of the osteophytes between the upper and lower vertebrae was evaluated as score B (0-2 points). Age estimation equations were developed using regression analyses with seven variables, determined by scores O and B, and the equation with the smallest standard error of estimate (SEE) was obtained when the number of vertebrae with score O ≥ 2 was used as the explanatory variable. Age estimation with SEE of about 10 years was possible even when partial vertebrae with a high degree of osteophyte formation were used, showing its potential for practical application. The cutoff value for age estimation was established using the receiver operating characteristic curve analysis, wherein good results were obtained for all variables (area under the curve ≥ 0.8). The combination of the estimation equation and the cutoff value can narrow the range of age estimates.

Trends and Characteristics in Health Care-related Deaths Investigated through Medico-legal Autopsies after System Changes in Japan.

In Japan, a new cause-of-death investigation system and related new laws were enacted in the mid-2010s. These laws provided for an autopsy system for non-criminal unnatural deaths and a medical accident investigation system outside the criminal justice process for health care-related deaths. We retrospectively explored changes in the number and characteristics of medico-legal autopsy cases of health care-related deaths in Chiba Prefecture, Japan, and examined trends over time during these reforms. We found that the percentage of forensic autopsies based on the Code of Criminal Procedure for health care-related deaths had decreased significantly. The number of autopsies of accidental and unintentional deaths in nursing homes, which are not covered by the newly established medical accident investigation system, has been increasing, reflecting the ageing of society. The trend toward decriminalisation of health care-related deaths was expected to contribute more to medical safety if the scope was expanded and a system for disclosure of autopsy information was established.

Postmortem magnetic resonance imaging revealed bilateral globi pallidi lesions in a death associated with prolonged carbon monoxide poisoning: a case report.

A man and a woman were found dead in the same car with a burned coal briquette. The cause of death of the woman was assigned to acute carbon monoxide (CO) poisoning without difficulty based on typical findings associated with this condition, including elevation of carboxyhaemoglobin (COHb). However, the man had an unremarkable elevation of COHb and a higher rectal temperature compared to that of the woman. Postmortem computed tomography (PMCT) revealed ambiguous low-density areas in the bilateral globi pallidi. Further analysis by postmortem magnetic resonance (PMMR) imaging showed these lesions more clearly; the lesions appeared as marked high signal intensity areas on both the T2-weighted images and the fluid-attenuated inversion recovery sequences. A subsequent autopsy revealed signs of pneumonia, dehydration, starvation, and hypothermia, suggesting that the man died from prolonged CO poisoning. Both globi pallidi contained grossly ambiguous lesions, and a detailed neuropathologic investigation revealed these lesions to be coagulative necrotic areas; this finding was compatible with a diagnosis of prolonged CO poisoning. This case report shows that postmortem imaging, especially PMMR, is useful for detecting necrotic lesions associated with prolonged CO poisoning. This report further exemplifies the utility of PMMR for detecting brain lesions, which may be difficult to detect by macroscopic analysis.

Sudden death due to tension pneumothorax associated with pulmonary tuberculosis.

A man in his seventies who lived alone was found dead in his home. Postmortem computed tomography (CT) performed prior to autopsy showed right-sided tension pneumothorax. Autopsy revealed an active pulmonary tuberculosis (TB) lesion. Macroscopic and histopathological findings showed pleural infiltration by TB lesions, suggesting that tension pneumothorax developed in association with TB infection. Routine postmortem CT performed prior to autopsy is useful in screening for TB because the presence of TB lesions can be confirmed from characteristic pulmonary findings. However, it may be difficult to identify tuberculous pulmonary lesions on CT if pneumothorax occurs and the lung collapses completely as in this case. Thus, forensic pathologists and radiologists should be cognizant of this rare complication of TB.

Preoperative Diagnosis of a Torsioned Accessory Spleen.

We report a case of a 12-year-old boy with an accessory spleen torsion. He presented with left-sided abdominal pain after trauma. A 4 cm oval mass without contrast enhancement was detected on contrast-enhanced computed tomography (CT), and ultrasound (US) showed a 4 cm oval mass below the spleen. The mass mainly consisted of high echoes similar to the spleen; the central part showed irregularly low echoes. Subsequent follow-up daily US examinations showed gradual expansion of the central low echoes with conspicuous hyperechoic dots. Discontinuation of the branch from the splenic artery to the mass was observed, both, on US and CT. These findings led to the diagnosis of a hemorrhagic infarct caused by torsion of the accessory spleen. Laparoscopy showed adherence of the accessory spleen to the omentum and colon by twisting four times around its axis. It was resected and confirmed the diagnosis of a torsioned accessory spleen.

Postmortem CT and MRI findings of massive fat embolism.

OBJECTIVE: To elucidate postmortem computed tomography (PMCT) and postmortem magnetic resonance (PMMR) imaging findings suggesting massive fat embolism. MATERIALS AND METHODS: Consecutive forensic cases with PMCT and PMMR scans of subjects prior to autopsy were assessed. For PMCT, 16- or 64-row multidetector CT scans were used; for PMMR, a 1.5 T system was used. MRI sequences of the chest area included T2- and T1-weighted fast spin-echo imaging, T2*-weighted imaging, T1-weighted 3-dimensional gradient-echo imaging with or without a fat-suppression pulse, short tau inversion recovery, and in-phase/opposed-phase imaging. At autopsy, forensic pathologists checked for pulmonary fat embolism with fat staining; Falzi's grading system was used for classification. RESULTS: Of 31 subjects, four were excluded because fat staining for histopathological examination of the lung tissue could not be performed. In three of the remaining 27 subjects, histology revealed massive fat embolism (Falzi grade III) and the cause of death was considered to be associated with fat embolism. CT detected a "fat-fluid level" in the right heart or intraluminal fat in the pulmonary arterial branches in two subjects. MRI detected these findings more clearly in both subjects. In one subject, CT and MRI were both negative. There were no positive findings in the 24 subjects that were fat embolism-negative by histology. DISCUSSION AND CONCLUSION: In some subjects, a massive fat embolism can be suggested by postmortem imaging with a "fat-fluid level" in the right heart or intraluminal fat in the pulmonary arterial branches. PMMR potentially suggests fat embolism more clearly than PMCT.

A clinical review of ovarian tumors in children and adolescents.

PURPOSE: To determine the features which predict torsion and the pre-operative indicators of malignancy in cases of ovarian torsion in ovarian tumors (OTs) in children. METHODS: The medical records of 35 pediatric patients who underwent surgery for OT, except for neonate cases, from 1997 to 2018 at our institution were reviewed retrospectively. RESULTS: The pathological diagnosis was mature teratoma in 17, immature teratoma in 9, yolk sac tumor in 3, and others in 6. The preoperative diagnosis, which was made based on the imaging findings and the serum tumor marker values, matched with the pathological diagnosis in 29/35 (83%). Ovarian torsion occurred in 14/35 (40%). All but one case that presented with torsion had intermittent abdominal pain as the primary symptom. The preoperative white blood cell count was significantly higher in cases where ovary preservation was impossible than where it was possible (p = 0.01) among the cases presenting with torsion. CONCLUSION: Preoperative imaging findings and the serum tumor marker values enabled us to make an accurate preoperative diagnosis. Patients with intermittent abdominal primary symptoms were more likely to have ovarian torsion than those without such symptoms, and leukocytosis may indicate irreversible ischemic changes in the affected ovary.

Fatal hemorrhage complicated with methamphetamine poisoning and its post-mortem CT features.

The purpose of this study was to assess the incidence of fatal hemorrhage complicated with methamphetamine (MA) poisoning and to examine the postmortem computed tomography (PMCT) features of fatal intracerebral hemorrhage (ICH) with and without MA poisoning. The study also attempted to determine the differences in PMCT between those two groups. Consecutive medicolegal autopsy data from November 2011 to February 2018 were searched for 3044 cases. First, the incidence and distribution of all cases of nontraumatic fatal hemorrhage with various causes were examined. Second, cases of ICH on the basal ganglia and brain stem were extracted. The PMCT findings were compared with respect to nine parameters: volume of hematoma, ventricular perforation, midline shift distance, aortic calcification, calcification of aortic valve, calcification of coronary artery, cardiothoracic ratio, circumference of ascending aorta, and volume of bladder contents. Of the 3044 cases, 97 were nontraumatic fatal hemorrhage; of these 97 cases, 20 were classified as MA poisoning with 9 ICH cases, and 60 cases were classified as non-MA poisoning with 14 ICH cases. A statistically significant difference in ages was observed between the two groups. On PMCT comparison of ICH, statistically significant differences were evident in the midline shift distance and calcification of the aortic valve. Forensic radiologists should be aware of the possibility of ICH with MA poisoning if fatal hemorrhage is detected on PMCT. Younger age, less calcification of the aortic valve, and a remarkable midline shift may be the keys to recognition.

Postmortem angiography revealing traumatic rupture of the intracranial internal carotid artery.

Diagnosis of traumatic subarachnoid hemorrhage (SAH), although relatively rare, is important in forensic medicine. It is mostly associated with rupture of the vertebrobasilar artery. Traumatic aneurysm of the intracranial part of the internal carotid artery (ICA) is also rare but has been reported in several studies. It is thought that the intracranial ICA is injured by blunt force to the head, neck, and chest. However, traumatic SAH with fatal acute course resulting from rupture of the ICA is especially uncommon: only two fatal cases without an associated aneurysm have been reported in the English-language literature. Although detecting the arterial lesion is required to make a precise diagnosis, this is sometimes impossible by macroscopic examination at autopsy or by investigation after formalin-fixation according to the position of the lesion. We report a rare case of fatal traumatic SAH associated with intracranial ICA rupture. Postmortem computed tomography angiography was useful to confirm the lesion.

Determination of sex on the basis of hyoid bone measurements in a Japanese population using multidetector computed tomography.

Sex determination for unidentified human remains is important because the determined sex is usually used as a foundation for the estimation of other biological profiles. This study investigated the sexual dimorphism of the adult hyoid bone and developed discriminant equations to accurately estimate sex in a contemporary Japanese population using measurements on two-dimensional computed tomography (CT) images. The study sample comprised 280 cadavers (140 males, 140 females) of known age and sex that underwent postmortem CT and subsequent forensic autopsy. In accordance with previous studies, seven measurements were performed using two-dimensional CT reconstructed images. Most measurements of males were significantly greater than those of females. The perpendicular length from the most anterior edge of the hyoid body to the line that connects the most distal points of the greater horns of the hyoid and the linear distance between the most lateral edges of the hyoid body most significantly contributed to sex determination. This study demonstrated that discriminant functions on the basis of three measurements provided higher rates of accurate sex classification (93.3-94.6%) than univariate functions. Therefore, the hyoid bone is highly sexually dimorphic in the contemporary Japanese population and may be useful in forensic contexts for sex determination with a high level of accuracy.

Stature estimation based on femoral measurements in the modern Japanese population: a cadaveric study using multidetector computed tomography.

We aimed to reproduce the anthropometrical measurement of femoral dimensions using multi-planar reconstruction computed tomography (CT), assess the correlation between stature and femoral measurements obtained by this approach, and establish a regression equation for estimating stature in the modern Japanese population. We used data regarding 224 cadavers (116 males, 108 females) that were subjected to postmortem CT and subsequent forensic autopsy at our department between October 2009 and July 2016. To simulate the placement of the femur on the osteometric board using reconstructed CT images, we defined a virtual horizontal plane (VHP) based on the three most dorsal points of the femur (lateral condyle, medial condyle, and greater trochanter). Five femoral measurements including the maximum femoral length (MFL) were obtained. The correlations between stature and each femoral measurement were expressed in terms of the coefficient of determination (R2). On regression analysis, MFL provided the lowest value for the standard error of the estimation (SEE); the SEE values in all subjects, males, and females, respectively, were 3.783 cm (R2 = 0.832), 3.850 cm (R2 = 0.653), and 3.340 cm (R2 = 0.760) for MFL on the left side and 3.747 cm (R2 = 0.835), 3.847 cm (R2 = 0.650), and 3.290 cm (R2 = 0.687) for MFL on the right side. Multiple regression equations using MFL and femoral epicondylar breadth were slightly superior to simple regression equations in males and in all subjects (SEE = 3.44-3.55 cm), whereas no effective equation could be obtained in females. To our knowledge, this is the first multiple regression equation for stature estimation using only femoral measurements.

Effect of Terminal-Group Functionality on the Ability of Dendrimers to Bind Proteins.

It is known that dendrimers can bind proteins with good selectively. This selectivity comes about from an optimization based on matching the size of the dendrimer with the size of the protein's interfacial binding area. In this paper, we report how this selectivity can be moderated by the functionality on the surface of the dendrimer. Specifically, we describe the synthesis of amino acid functionalized dendrimers and the effect of functionality on the dendrimer's ability to bind and inhibit the enzymatic protein, chymotrypsin. The results show how dendrimer binding can be increased or decreased depending on the terminal functionality. These results will allow new ligands to be designed and synthesized, possessing increased and selective protein-binding abilities.

Frequency and influencing factors of cardiopulmonary resuscitation-related injuries during implementation of the American Heart Association 2010 Guidelines: a retrospective study based on autopsy and postmortem computed tomography.

AIM: To determine the frequency of cardiopulmonary resuscitation (CPR)-related injuries and factors involved in their occurrence, data based on forensic autopsy and postmortem computed tomography (PMCT) during implementation of the 2010 American Heart Association Guidelines for CPR were studied. METHODS: We retrospectively evaluated data on adult patients with non-traumatic deaths who had undergone manual CPR and autopsy from January 2012 to December 2014. CPR-related injuries were analyzed on autopsy records and PMCT images and compared with results of previous studies. RESULTS: In total, 180 consecutive cases were analyzed. Rib fractures and sternal fractures were most frequent (overall frequency, 66.1 and 52.8%, respectively), followed by heart injuries (12.8%) and abdominal visceral injuries (2.2%). Urgently life-threatening injuries were rare (2.8%). Older age was an independent risk factor for rib fracture [adjusted odds ratio (AOR), 1.06; 95% confidence interval (CI), 1.04-1.08; p < 0.001], ≥ 3 rib fractures (AOR, 1.06; 95% CI, 1.02-1.09; p = 0.002), and sternal fracture (AOR, 1.03; 95% CI, 1.01-1.05; p < 0.001). Female sex was significantly associated with sternal fracture (AOR, 2.08; 95% CI, 1.02-4.25; p = 0.04). Chest compression only by laypersons was inversely associated with rib and sternal fractures. Body mass index and in-hospital cardiac arrest were not significantly associated with any complications. The frequency of thoracic skeletal injuries was similar to that in recent autopsy-based studies. CONCLUSIONS: Implementation of the 2010 Guidelines had little impact on the frequency of CPR-related thoracic skeletal injuries or urgently life-threatening complications. Older age was the only independent factor related to thoracic skeletal injuries.

Efficient isolation of human metapneumovirus using MNT-1, a human malignant melanoma cell line with early and distinct cytopathic effects.

Isolation of human metapneumovirus (HMPV) from clinical specimens is currently inefficient because of the lack of a cell culture system in which a distinct cytopathic effect (CPE) occurs. The cell lines LLC-MK2, Vero and Vero E6 are used for isolation of HMPV; however, the CPE in these cell lines is subtle and usually requires a long observation period and sometimes blind passages. Thus, a cell line in which an early and distinct CPE occurs following HMPV inoculation is highly desired by clinical virology laboratories. In this study, it was demonstrated that, in the human malignant melanoma cell line MNT-1, obvious syncytium formation occurs shortly after inoculation with HMPV-positive clinical specimens. In addition, the growth and efficiency of isolation of HMPV were greater using MNT-1 than using any other conventional cell line. Addition of this cell line to our routine viral isolation system for clinical specimens markedly enhanced isolation frequency, allowing isolation-based surveillance. MNT-1 has the potential to facilitate clinical and epidemiological studies of HMPV.

Fatal right coronary artery rupture following blunt chest trauma: detection by postmortem selective coronary angiography.

Coronary artery injury is a rare complication following blunt chest trauma (BCT), and can be fatal. Here we report findings on postmortem selective coronary angiography of right coronary artery rupture after an assault involving blunt trauma to the chest. A woman in her 60s died after her son stomped on her chest. There were no appreciable signs of injury on external examination, and cause of death could not be determined by postmortem computed tomography (PMCT). Internal findings indicated that an external force had been applied to the anterior chest, as evidenced by subcutaneous hemorrhage and pericardial and cardiac contusions. Postmortem coronary angiography revealed irregularity of the intima and of the fat tissue surrounding the proximal part of the right coronary artery associated with a local filling defect. Histopathological examination suggested coronary rupture with dissection of the tunica media and compression of the lumen cavity. The key points in the present case are that no fatal injuries could be determined on external examination, and the heart and coronary artery injuries were not evident on PMCT. Criminality might be overlooked in such cases, as external investigation at the crime scene would be inadequate and could result in a facile diagnosis of cause of death. This is the first report of coronary artery rupture with dissection that was detected by CT coronary angiography, and provides helpful findings for reaching an appropriate decision both forensically and clinically.

A case of acute subdural hematoma due to ruptured aneurysm detected by postmortem angiography.

Acute subdural hematoma (ASDH) is mostly caused by head trauma, but intrinsic causes also exist such as aneurysm rupture. We describe here a case involving a man in his 70s who was found lying on the bedroom floor by his family. CT performed at the hospital showed ASDH and a forensic autopsy was requested. Postmortem cerebral angiography showed dilatation of the bifurcation of the middle cerebral artery, which coincided with the dilated part of the Sylvian fissure. Extravasation of contrast medium into the subdural hematoma from this site was suggestive of a ruptured aneurysm. Autopsy revealed a fleshy hematoma (total weight 110 g) in the right subdural space and findings of brain herniation. As indicated on angiography, a ruptured saccular aneurysm was confirmed at the bifurcation of the middle cerebral artery. Obvious injuries to the head or face could not be detected on either external or internal examination, and intrinsic ASDH due to a ruptured middle cerebral artery aneurysm was determined as the cause of death. One of the key points of forensic diagnosis is the strict differentiation between intrinsic and extrinsic onset for conditions leading to death. Although most subdural hematomas (SDH) are caused by extrinsic factors, forensic pathologists should consider the possibility of intrinsic SDH. In addition, postmortem angiography can be useful for identifying vascular lesions in such cases.

An unusual autopsy case of lethal hypothermia exacerbated by body lice-induced severe anemia.

Pediculus humanus humanus (known as body lice) are commonly found in the folds of clothes, and can cause skin disorders when they feed on human blood, resulting in an itching sensation. Body lice are known as vectors of infectious diseases, including typhus, recurrent fever, and trench fever. An infestation with blood-sucking body lice induces severe cutaneous pruritus, and this skin disorder is known as "vagabond's disease." A body lice infestation is sometimes complicated with iron deficiency anemia. In the present case, a man in his late 70s died of lethal hypothermia in the outdoors during the winter season. The case history and autopsy findings revealed that the cause of the lethal hypothermia was iron deficiency anemia, which was associated with a prolonged infestation of blood-sucking body lice. Also, he had vagabond's disease because the skin on his body was abnormal and highly pigmented. This is an unusual autopsy case since the body lice contributed to the cause of the death.

Efficient isolation of human parainfluenza viruses 1 and 3 using MNT-1, a human malignant melanoma cell line system that exhibits an apparent cytopathic effect.

Isolation of human parainfluenza virus (HPIV) serotypes 1 and 3 from clinical specimens is not very efficient because of the lack of a cell culture system capable of inducing CPE. In this study, the utility of a melanoma cell line, MNT-1, that allows HPIV growth and displays CPE was demonstrated. In particularly, the efficiency of isolating HPIV1 and HPIV3 using MNT-1 was greater than for cell lines conventionally used for HPIV isolation. Our demonstrated efficacy of HPIV1 and HPIV3 isolation with apparent CPE using the MNT-1 cell culture system has the potential to improve virus isolation from clinical specimens.