千葉 文子

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.

We report a fatal case of airway obstruction caused by spontaneous retropharyngeal hematoma (RH) in the setting of treatment with dipyridamole. A 90-year-old woman presented with cervical swelling, neck and chest ecchymoses, and complaints of dyspnea. She suffered cardiopulmonary arrest in the ambulance, and her death was confirmed after transportation to the hospital. The major finding of postmortem computed tomography (PMCT) prior to autopsy was widening of the prevertebral soft tissue. The results of the autopsy indicated that the cause of death was mechanical asphyxia, secondary to pharyngeal and laryngeal compression caused by the RH. There were no evident injuries, medical interventions, or particular diseases, suggesting the spontaneous cause of the RH. To the best of our knowledge, this is the first report of a fatal case secondary to spontaneous RH that was revealed through PMCT imaging.

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.

Age estimation of cadavers from post-mortem "chest plate" using conventional radiography, which involves radiographic assessment of ossification around the sternum and rib ends, has been evaluated without fruitful results. This study examined the value of images of the chest plate obtained by three-dimensional post-mortem CT for estimation of age at time of death in a Japanese population. Five chest plate ossification scores were evaluated in 320 subjects, including ossification of the first costal cartilage (OF), ossification of the second to seventh costal cartilages at the rib (OR) and sternal (OS) ends, fusion of the manubriosternal joint (FM), and fusion of the xiphisternal joint (FX). OS was found to have the highest correlation with age while FM had no significant correlation. The best composite score for age estimation was the summative score for both sides of the OS and the right side of the OF and FX, for which the coefficient of determination (R2) and the standard error of estimation (SEE) were 0.608 and 12.44 years, respectively, for men and 0.590 and 14.65 years for women. The accuracy of the model was tested in a further 26 male and 24 female subjects, and the accuracy rate within the first SEE was 57.69% and 70.83%, respectively. This rapid and non-invasive method of age estimation in the chest plate area is superior to conventional methods and could be useful for estimation of age at time of death in the Japanese population.

We report a case of fatal olanzapine-induced ketoacidosis in which pneumomediastinum (PM) and subcutaneous emphysema (SE) were detected on postmortem computed tomographic (CT) images. A man in his forties was found in a state of cardiopulmonary arrest with profuse perspiration, and 50 empty capsules of olanzapine (10 mg) and flunitrazepam (1 mg) were found in his room. The major findings of postmortem CT prior to autopsy were PM and SE from the lower half of the face to the height of the first rib. The results of autopsy, biochemical tests, and toxicological analyses indicated the cause of death to be fatal ketoacidosis induced by olanzapine intoxication. No injuries, medical interventions, or particular diseases were evident, suggesting that PM and SE were caused by ketoacidosis. Our findings indicated that toxicological analyses should be performed when PM and SE are detected on CT images.

To estimate forensic age, the Study Group of Forensic Age Diagnostics of the German Association of Forensic Medicine (AGFAD) has recommended the radiological investigation of the medial clavicular epiphysis (MCE). This study aimed to investigate the relation between the maturation of the MCE and age in a contemporary Japanese population using a standard five-stage system by Schmeling et al. and Kellinghaus substage system. A total of 207 cadavers (128 males, 79 females) of known age and sex that underwent postmortem computed tomography (CT) and subsequent forensic autopsy were obtained. The earliest appearance for stage 3c was 18.1 years in the male subjects and 18.4 years in the female subjects. Our results were consistent with those in previous studies and indicate that stage 3c is crucial for medico-legal processes in evaluating age in various countries. Similar studies on the staging of the MCE using CT images in other populations, particularly in Asians, are required.

A 5-year-old boy with a chromosome-9 abnormality and multiple external and visceral malformations was found in cardiopulmonary arrest during a regular visit to the hospital; he did not respond to cardiopulmonary resuscitation and died. An odontoid process fracture and calcification and fibrosis of the muscles around the superior cervical vertebra were observed during the autopsy. Postmortem computed tomography revealed an anterior dislocation of the atlas; odontoid synchondrosis fracture; and delayed, incomplete bony fusion of the odontoid process relative to his age. The cause of his death was a superior spinal cord injury. The tissue surrounding the upper cervical spine presented with myositis ossificans, suggesting a prior injury. He experienced a minor traffic accident 3 months before his death. It was concluded that the odontoid synchondrosis fracture occurred during the accident based on the incomplete bony fusion and atlantoaxial instability, which were consistent with the findings of myositis ossificans. Delayed fatal dislocation may then have occurred under the influence of a minor external force. Odontoid process abnormalities and atlantoaxial instability are common in patients with trisomy 21 and other congenital diseases; however, the condition's association with chromosome-9 abnormalities has not been reported. In children with various chromosomal abnormalities, periodic assessment of instability and morphology of the cervical spine, and a lowered examination threshold for the children at risk, could prove useful in the prevention injuries leading to fatality, and provide additional information to rule out abuse.

Atmospheric radiocarbon (14C) levels increased from 1955 to 1963 due to atmospheric nuclear weapon tests, and then decreased. As 14C accumulates in human tooth enamel while the enamel is being formed, 14C can be used to estimate the birth year of unidentified bodies. Measurement results of 14C content in tooth enamel using accelerator mass spectrometry vary depending on the enamel's sample site. To address this problem, a method for equalizing samples using a pulverizer was considered in this study. Regarding the tube and cone used as the pulverizer, (1) a polycarbonate tube and stainless steel cone, (2) a stainless steel tube and cone, and (3) a tungsten carbide tube and cone, were compared. In (1), the modern carbon ratio was approximately half that of the normal ratio of 100 pMC, with which accurate dating was impossible, and in (2), a high background value was obtained for IAEA-C1, which was pulverized using a reusable tube and cone. In (3), the 14C content for IAEA-C1 pulverized using reusable tube and cone, which was washed with quartz sand, was 0.31 ± 0.01 pMC. This result did not show any problems regarding background value. Therefore, the use of tungsten carbide products and washing with quartz sand is recommended for 14C measurement of pulverized teeth.

We aimed to reproduce the anthropometrical measurements of femoral dimensions using multi-planar reconstruction (MPR) computed tomography (CT); to assess the feasibility of sex estimation using femoral measurements through this approach, and to establish the corresponding sex estimation thresholds in the modern Japanese population. We used data on 224 cadavers (116 male and 108 female) that were subjected to postmortem CT and subsequent forensic autopsy at our department between October 2009 and July 2016. Four femoral measurements were obtained. Receiver operating characteristic (ROC) curve analysis was performed to test the overall ability of the variables in sex estimation, while the accuracy of the sex estimation was measured by the area under the ROC curve (AUC). The femoral bicondylar breadth showed the largest AUC values (left; 0.973, right; 0.974), followed by the maximum head diameter (left; 0.951, right; 0.955), and maximum femoral length (left; 0.885, right; 0.887). To the best of our knowledge, this is the first report to assess sex estimation based on femoral measurements, using MPR CT images.

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.

Long QT syndrome (LQTS), a congenital genetic disorder, can cause torsades de pointes (TdP), and lethal cardiac arrhythmia may result from ingestion of cardiotoxic drugs. Methamphetamine (MP) and new psychoactive substances (NPSs) can trigger TdP due to QT prolongation, leading to sudden death. We therefore analysed variations in the LQTS-associated genes KCNQ1 (LQT1) and KCNH2 (LQT2) using cardiac blood and myocardial tissue from subjects having died suddenly during MP or NPS use to investigate the relationship between congenital genetic abnormalities and sudden death during illegal drug use. We amplified and sequenced all exons of these genes using samples from 20 subjects, half of whom had died taking MP and half after using NPSs. G643S, a KCNQ1 missense polymorphism, was significantly more common among sudden deaths involving NPSs (6 subjects) than those involving MP (1 subject) and healthy Japanese subjects (P = 0.001). Notably, synthetic cathinones were detected in 2 of 3 cases involving G643S carriers. Previous functional analyses have indicated that the G643S polymorphism in the KCNQ1 potassium channel gene causes mild IKs channel dysfunction. Our data suggest that use of NPSs, particularly synthetic cathinones, is associated with elevated risk of serious cardiac arrhythmia and sudden death for subjects carrying KCNQ1 G643S.

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.

Accurate sex estimation from unknown human remains is crucial as an integral and foremost step toward individual identification. The aims of this study were to assess sexual dimorphism of the clavicle and develop discriminant equations for sex estimation in a modern adult Japanese population based on clavicular measurements using three-dimensional (3D) computed tomographic (CT) images. A total of 300 cadavers (150 males, 150 females) of known age and sex that underwent postmortem CT and subsequent forensic autopsy were obtained. Four measurements were performed using 3D CT reconstructed images that extracted only bones based on the CT values, as follows: the linear distances between the medial superior margins of the left and right sternal facets to the lateral points of the left and right acromial ends, and the linear distances between the medial superior margins of the left and right sternal facets to the tips of the left and right conoid tubercles. The mean values of all measurements were significantly greater for male subjects than female subjects. Univariate discriminant function analysis (DFA) provided correct sex prediction rates of 88.3-92.2%. Stepwise DFA for the left and right clavicles yielded sex classification accuracy rates of 92.2% and 91.0%, respectively. In conclusion, clavicular measurements using 3D CT images of a contemporary Japanese population may be useful for sex estimation in forensic contexts.

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.

Analysis of ions in sphenoidal fluid can be a useful index for the diagnosis of drowning. We evaluated the reference ranges of non-drowning cases using statistical methods and three indices: sodium ion (Na+), summation of sodium and potassium ions (SUMNa+K), and summation of sodium, potassium and chloride ions (SUMNa+K+Cl). The reference ranges were 96≤Na+<152, 139≤SUMNa+K<179, 243≤SUMNa+K+Cl<311(mEq/L), respectively. Victim indices outside of the reference ranges indicate that the victim probably inspired water with higher or lower ion concentrations than those of body fluid in sphenoidal sinuses. Compared to the SUMNa+K+Cl index, the Na+ and SUMNa+K indices could distinguish among seawater drowning, freshwater drowning, and non-drowning. In drowning cases, sphenoidal fluid volume and time since death were not correlated, which suggests that water does not enter the sphenoidal sinuses after death and there is a different process for water accumulation in drowning and non-drowning cases. In bathtub cases, this method was not valid for the estimation of inspired water. Although it is necessary to observe the classical signs of drowning, this method is suitable for the estimation of drowning, especially in cases where pleural fluid or diatom tests are not available.

OBJECTIVES: To clarify the differences between postmortem CT (PMCT) and autopsy findings in the postmortem detection of cervical spine injuries (CSIs). MATERIALS AND METHODS: Our department's forensic pathology database was searched for CSI cases. In each case, the autopsy data and radiologists' interpretations were reviewed for the presence of bone fractures and intervertebral injuries. RESULTS: The study included 42 cases. For both bone fractures and intervertebral injuries, no substantial concordance between PMCT and autopsy findings was observed (McNemar's test: p<0.001 and p<0.001, respectively). Regarding bone fractures, more injuries were detected with CT than with autopsy (CT: 74, autopsy: 23). The percentage of CT-detected fractures that were missed at autopsy (77.0%, 57/74) was higher than the percentage of autopsy-detected fractures missed with CT (26.1%, 6/23). Regarding intervertebral injuries, fewer injuries were detected with CT than with autopsy (CT: 40, autopsy: 80). The percentage of CT-detected injuries that were missed at autopsy (35.0%, 14/40) was lower than the percentage of autopsy-detected injuries that were missed with CT (67.5%, 54/80). CONCLUSIONS: A substantial number of CSIs were detected by either PMCT or autopsy alone. Accurate evaluation for CSI requires the use of both methods.

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.

The aims of this study was to assess the correlation between stature and clavicular measurements in a contemporary Japanese population using three-dimensional (3D) computed tomographic (CT) images, and to establish regression equations for predicting stature. A total of 249 cadavers (131 males, 118 females) underwent postmortem CT scanning and subsequent forensic autopsy between October 2011 and May 2016 in our department. Four clavicular variables (linear distances between the superior margins of the left and right sternal facets to the anterior points of the left and right acromial ends and between the superior margins of the left and right sternal facets to the left and right conoid tubercles) were measured using 3D CT reconstructed images that extracted only bone data. The correlations between stature and each of the clavicular measurements were assessed with Pearson product-moment correlation coefficients. These clavicular measurements correlated significantly with stature in both sexes. The lowest standard error of estimation value in all, male, and female subjects was 3.62cm (r2=0.836), 3.55cm (r2=0.566), and 3.43cm (r2=0.663), respectively. In conclusion, clavicular measurements obtained from 3D CT images may be useful for stature estimation of Japanese individuals, particularly in cases where better predictors, such as long bones, are not available.

Population aging is rapidly advancing in numerous parts of the world and, accordingly, the prevalence of Alzheimer's disease (AD) is rising. The safety of donepezil (DPZ), which is used for AD treatment, has been established in clinical trials. However, some studies have indicated that DPZ may be associated with severe cardiac side effects, and excessive doses may induce toxicity-related symptoms or death. Therefore, the measurement of blood DPZ levels is important for the postmortem investigation of related causes of death. However, postmortem drug concentrations in the blood may not always reflect those obtained antemortem because of the postmortem redistribution (PMR) of drugs. Therefore, the aim of this study was to investigate the potential PMR of DPZ using a rat model. The DPZ concentration was measured using a validated HPLC/Q-TOF-MS system in cardiac and peripheral blood, and in the brain, lungs, myocardium, liver, and thigh muscle at different postmortem intervals (0, 1, 3, 6, 12, and 24h). Overall, the DPZ tissue to peripheral blood ratio decreased throughout the postmortem period. Furthermore, the DPZ concentration increased in the peripheral and cardiac blood but decreased in both of the lungs, postmortem. Furthermore, the blood pH was significantly lowered. We used a perfusion approach to examine the rat lung and heart to further investigate the relationship between the pH and DPZ release from the lungs. The outflow concentrations when the inflow pH changed from 7.4 to 5.5 were approximately 2-fold higher than the inflow pH fixed 7.4. These findings suggest that the antemortem accumulated DPZ in the lungs is released into the pulmonary blood owing to postmortem acidification of blood, and subsequently flows into the cardiac blood, leading to the observed increase in concentration. Although we could not determine the underlying mechanism, we confirmed that PMR occurs similarly in the cardiac and peripheral blood.

Accurate sex estimation is important in forensic investigation to determine the identity of unknown individuals. The aim of this study was to investigate the accuracy of sex assessment based on measurements of the second cervical vertebra (C2) using computed tomographic (CT) images in a Japanese population and to develop discriminant function formulae. The data were collected from 224 Japanese cadavers (112 male subjects, 112 female subjects) on which postmortem CT scanning and subsequent forensic autopsy were performed. Nine CT measurements of the C2 were performed for CT images of each subject. The measurements were assessed using descriptive statistics and discriminant function analyses (DFA). All of the measurements demonstrated significant sexual dimorphism. Multiple DFA with stepwise variable selection resulted in multivariable models; a five-variable model reached an accuracy rate of 92.9%. Our results suggest that metric analysis based on CT images of the C2 can accurately determine the sex from the human skeletal remains in a contemporary Japanese population and may be useful for sex estimation in forensic anthropology.

PURPOSE: The purpose of this study was to determine the incidence of three-rooted mandibular first molars in a contemporary Japanese population using multidetector computed tomography (MDCT) and examine whether this characteristic root form may be useful for identification purposes. METHODS: Prior to their forensic autopsies, we obtained MDCT scans of 365 cadavers (255 males, 110 females) with mandibular first molars on both sides. Altogether, 730 mandibular first molars were examined morphologically on reconstructed CT images, and the incidence of three-rooted molars was recorded. The results were analyzed statistically to determine sex and left-right differences using the chi-square test. RESULTS: In all, 189 (25.9%) of the 730 mandibular first molars had three roots: 79 (31.0%) in the 255 males and 35 (31.8%) in the 110 females. No statistically significant difference was found between the sexes. In the 39 individuals who had unilateral three-rooted mandibular first molars, 7 (17.9%) were on the left side and 32 (82.1%) were on the right side, indicating a statistically significant predominance on the right side. CONCLUSIONS: The incidence of three-rooted mandibular first molars in contemporary Japanese individuals was 25.9%, with no statistically significant sex difference, but in the case of unilateral three-rooted teeth, with a statistically significant predominance on the right side. Our study found that Japanese and northeastern Asians have a high incidence of the three-rooted mandibular first molars among individuals of Mongolian origin; this finding may be a useful screening tool for identification of unknown individuals.

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.

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.

Accurate sex estimation based on measurements of dimorphic dimensions in human unknown remains is important as the first step toward making individual identification. The purpose of this study was to assess the sexual dimorphism of the scapula and to quantify the accuracy of sex estimation in a contemporary Japanese forensic sample using scapular measurements based on three-dimensional (3D) computed tomographic (CT) images. A total of 218 cadavers (109 males, 109 females) that underwent postmortem CT and subsequent forensic autopsy were used. Ten scapular measurements were performed on 3D CT reconstructed images that extracted only bone data, and were analyzed using descriptive statistics and discriminant function analyses (DFA). All measurements were dimorphic in terms of sex differences. Univariate DFA provided sex classification accuracy rates of 75.7-91.3%. Stepwise DFA yielded sex prediction accuracy rates of 93.1-94.5%. In conclusion, the scapular measurements using 3D CT images of a contemporary Japanese population may be useful for the estimation of skeletal sex in the field of forensic anthropology.

Traumatic rhabdomyolysis generally occurs after severe blunt trauma and is acute in onset, associated with severe disease, and potentially lethal. Accordingly, diagnosis of traumatic rhabdomyolysis in patients without massive subcutaneous or intramuscular hemorrhage is difficult, especially in the postmortem period, which is limited in terms of the availability of biochemical examination tools and accurate history of illness. To the best of our knowledge, there are no previous reports of death from traumatic rhabdomyolysis among individuals who did not pursue medical consultation. A previously healthy man in his early sixties had been punched and kicked several times in the previous 2months, but he had not gone to a hospital. He suddenly lost consciousness at his workplace approximately 5days after the most recent assault, and cardiopulmonary arrest occurred when the emergency service arrived. He died the same day, and a medicolegal autopsy was performed. Although several sites of minor subcutaneous and muscle hemorrhage were observed, the cause of death was unclear upon macroscopic assessment. Immunohistochemical staining revealed acute renal failure caused by rhabdomyolysis. We herein report a rare case of fatal traumatic rhabdomyolysis, seemingly associated with minor and apparently nonlethal muscle injury.

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.

The aim of this study was to assess the correlation between stature and cranial measurements in a contemporary Japanese population, using three-dimensional (3D) computed tomographic (CT) images. A total of 228 cadavers (123 males, 105 females) underwent postmortem CT scanning and subsequent forensic autopsy between May 2011 and April 2015. Five cranial measurements were taken from 3D CT reconstructed images that extracted only cranial data. The correlations between stature and each of the cranial measurements were assessed with Pearson product-moment correlation coefficients. Simple and multiple regression analyses showed significant correlations between stature and cranial measurements. In conclusion, cranial measurements obtained from 3D CT images may be useful for forensic estimation of the stature of Japanese individuals, particularly in cases where better predictors, such as long bones, are not available.

In this case study, we measured the concentration of memantine in the heart blood, peripheral blood, urine, liver, thigh muscle, and subcutaneous fat of a 64-year-old woman who was prescribed memantine for early-onset Alzheimer's disease. She died in hospital after an altercation with her husband. Cause of death was clearly not drug intoxication or overdose, so we investigated the postmortem redistribution (PMR) of memantine in the various tissues and blood ratios of the postmortem samples. Memantine concentrations detected were 1.31 μg/mL in the peripheral blood, 3.95 μg/mL in central blood, 2.09 μg/mL in the urine, 25.54 μg/g in the liver, 1.16 μg/g in the thigh muscle and 2.13 μg/g in the subcutaneous fat. In all samples, the concentrations were higher than the accepted therapeutic range (which is approximately 0.09-0.15 μg/mL). The central blood to peripheral blood (C/P) memantine ratio was 3.01 while the liver to peripheral blood (L/P) ratio was 19.5. It is documented that a C/P ratio exceeding 2 and L/P ratio exceeding 20 highlight a propensity for significant PMR. Although this is a single case study, our data suggest that memantine exhibits PMR. Additionally, a lowered pH was found in peripheral blood (pH 6.2) and central blood (pH 6.1). This postmortem reduction in blood pH may also promote the PMR of memantine. Because there is very little available postmortem toxicological data on memantine, our case study will serve as a foundation to assist in future forensic investigations.

Sex estimation of decomposed or skeletal remains is clearly important in forensic contexts. Recently, contemporary population-specific data has been obtained using multidetector computed tomography (MDCT) scanning. The main purpose of this study was to investigate skeletal pelvic dimorphism in a contemporary Japanese forensic sample and to quantify the accuracy of sex estimation using various pelvic measurements obtained from three-dimensional (3D) CT images. This study used a total of 208 cadavers (104 males, 104 females) of which postmortem CT scanning and subsequent forensic autopsy were conducted between December 2011 and August 2014. Eleven measurements of each pelvis were obtained from 3D CT reconstructed images that extracted only bone data. The measurements were analyzed using descriptive statistics and discriminant function analyses. All except one measurement were dimorphic in terms of sex differences. Univariate discriminant function analyses using these measurements provided sex classification accuracy rates of 62.0-98.1%. The subpubic angle was found to contribute most significantly to accurate sex estimation. Multivariate discriminant functions yielded sex prediction accuracy rates of 63.9-98.1%. In conclusion, the pelvic measurements obtained from 3D CT images of a contemporary Japanese population successfully demonstrated sexual dimorphism and may be useful for the estimation of skeletal sex in the field of forensic anthropology.

OBJECTIVE: The objective of this study was to determine whether selected postmortem unenhanced CT findings can discriminate between antemortem and postmortem pericardial hemorrhage. MATERIALS AND METHODS: Thirty-one consecutive cases of postmortem CT followed by autopsy identifying at least 50 mL of hemorrhaged blood were reviewed. Seven cases were classified as postmortem pericardial hemorrhage secondary to chest compression (postmortem group), and 24 cases were classified as antemortem pericardial hemorrhage secondary to disease or trauma (antemortem group), on the basis of autopsy findings. Postmortem CT findings of pericardial hemorrhage were classified as stratification comprising upper low-density and lower high-density areas (i.e., fluid-fluid level) and a high-density concentric ring (i.e., pericardial hyperdense ring). Diagnostic values for detecting antemortem or postmortem pericardial hemorrhage using this classification system, along with attenuation (in Hounsfield units) of pericardial hemorrhage lesions and the presence or absence of flattened heart sign on postmortem CT, were measured. RESULTS: There were statistically significant differences in fluid-fluid level and pericardial hyperdense ring between the postmortem and antemortem groups (p < 0.001). The sensitivity, specificity, positive predictive value, and negative predictive value of fluid-fluid level for detecting postmortem pericardial hemorrhage were 86%, 96%, 86%, and 100%, respectively. The mean attenuation of pericardial hemorrhage lesions differed statistically significantly between the groups (p = 0.004). The presentation of the flattened heart sign did not differ statistically significantly between the groups (p = 0.681). CONCLUSION: Fluid-fluid level and pericardial hyperdense ring on postmortem CT, combined with attenuation, are useful for differentiating between antemortem and postmortem pericardial hemorrhage secondary to chest compression.