Evaluation of the distribution of nicotine intravenous injection: an adult autopsy case report with a review of literature.

We reported the first comprehensive autopsy case of death due to intravenous injection of nicotine. We examined the distribution of nicotine in the body tissues and fluid and exposed the pathophysiology of nicotine poisoning. A 19-year-old woman was rushed to the hospital in cardiorespiratory arrest and was confirmed dead upon arrival. Liquid nicotine, hydrogen peroxide water, and a syringe were found in the hotel room where she stayed. On autopsy, nicotine concentration was the highest (15,023 µg/mg) in the tissue around the injection mark on the right upper arm. Among the body fluids, the intraperitoneal fluid had the highest, whereas the pericardial fluid had the lowest (0.736 µg/mL) nicotine concentration. Among the organs, the brain had the highest (11.637 µg/mg), whereas the fat tissue had the lowest (1.307 µg/mg) nicotine concentration. The concentration of cotinine, which is the metabolite of nicotine, was the highest in the tissue around the injection mark on the right arm (5.495 µg/mg) and was almost the same among the other body fluids and organs. The respective concentrations of nicotine and cotinine were 1.529 µg/mL and 0.019 µg/mL in the left heart blood and 3.157 µg/mL and 0.002 µg/mL in right heart blood. In this case, the nicotine concentrations in blood reached the lethal level. The distributions of nicotine and cotinine, as indicated by the intravenous injection, were related to the distribution of organs that metabolize nicotine and the distribution of nicotinic acetylcholine receptors.

Postmortem water contents of major organs with regard to the cause of death.

The water contents of individual organs are maintained in a narrow range, but altered in morbidity owing to a disturbance of water equilibrium. The present study investigated the tissue water contents of major organs with regard to the cause of death in serial autopsy cases within 3 days postmortem (n = 329; 223 males, 106 females; age range, 1-100 years). Individual tissue water contents differed markedly across organs, but no significant postmortem or survival-period dependence, gender-related difference, or age dependence was observed. However, the lung water contents were higher in drowning cases, especially in saltwater cases (p < 0.05), and in strangulation among the acute mechanical asphyxiation cases. The brain water contents were higher in hypothermia cases (cold exposure) and tended to be higher in hyperthermia cases (heatstroke). The kidney water contents were higher in drowning and acute cardiac cases than in fatal intoxication and fire fatality cases, but tended to be higher in fresh- and bathwater drowning cases than in saltwater cases (p > 0.05). The spleen water contents were higher in bathwater drowning than in saltwater and freshwater cases, but did not differ among other the causes of death. These findings suggest that the postmortem tissue water content of individual organs, especially the lungs and/or kidney, depends on the cause of death and particularly contributes to differentiation between saltwater and freshwater drowning, respectively. This work therefore provides insight into the investigation of varied tissue water imbalances during the death process. In conclusion, we recommend the measurement of tissue water content because it is easy to perform and appears to be useful for evaluating the pathophysiology of systemic circulatory failure.

Pathophysiological significance of clock genes BMAL1 and PER2 as erythropoietin-controlling factors in acute blood hemorrhage.

This study aimed to characterize the pathophysiology, including possible correlations, of clock gene expression and erythropoietin (EPO) production in the acute stage of blood hemorrhage. Specimens of human cortical tissues (right and left kidneys) and cardiac blood were collected at autopsy from 52 cases following mortality due to acute-stage blood hemorrhage following sharp instrument injury. BMAL1 and PER2 mRNA levels were determined by reverse transcription-polymerase chain reaction; BMAL1 and PER2 protein levels were assessed using immunohistochemistry; BMAL1 protein levels were quantitatively measured by western blotting; and serum EPO levels were measured by chemiluminescent enzyme immunoassay. Separately, a rat model of hemorrhagic conditions was generated and used to confirm the results obtained with autopsy-derived specimens. A positive correlation was observed between BMAL1 protein and serum EPO levels, but not between BMAL1 mRNA levels and serum EPO levels. We also noted that Per2 mRNA expression became elevated in humans who survived for > 3 h after acute hemorrhagic events, with subsequent decreases in serum EPO levels. The rat model showed that even short (30-min) intervals of blood loss yielded increases in both Bmal1 mRNA and serum EPO levels; longer (60-min) intervals resulted in increases in Per2 mRNA expression along with decreases in serum EPO. Thus, the acute-stage human hemorrhage cases and the rat hemorrhage model yielded similar tendencies for clock gene expression and EPO secretion. In conclusion, our results indicated that clock genes are involved in the regulation of EPO production during the early stages of hypoxia/ischemia resulting from the acute hemorrhagic events.

Effects of postmortem positional changes on conjunctival petechiae.

The present study aimed to determine whether postmortem period, physical constitution, cause of death, and cardiopulmonary resuscitation are associated with positional changes in the postmortem appearance of conjunctival petechiae. We retrospectively investigated serial forensic autopsies from 6 h to 6 days postmortem (n = 442; male, 303; female, 139; median age, 62 years; range, 0-100 years). The causes of death were sharp instrument injury, blunt force trauma, fire, intoxication, asphyxia, drowning, hypothermia, hyperthermia, acute heart failure, and natural causes. Of these, 28 (male, n = 18; female, n = 10) were aged ≤5 years. Palpebral conjunctival petechiae were initially assessed at autopsy in supine bodies, then reassessed in prone bodies after 30 min. Among 414 bodies, 291 (70.2%) and 123 (29.7%) who were aged between 6 and 100 years, and 18 (64.2%) and 10 (35.7%) aged <5 years at the time of death, were discovered in the supine and prone positions, respectively. The amounts of petechiae increased within 1.5 days postmortem, but not in those discovered in the prone position. The rates at which petechiae increased were higher in supine overweight bodies (BMI ≥ 25.0) and in those who were discovered supine and had died of asphyxia or drowning (37.5%). Cardiopulmonary resuscitation for bodies discovered in the supine and prone positions did not statistically affect the occurrence of petechiae. Several postmortem factors can cause hypostatic blood redistribution that manifests as increased amounts of petechiae in the palpebral conjunctivae.

Analysis of psychotropic drug-related deaths in south Osaka.

OBJECTIVE: The aim of this study was to investigate the occurrence of deaths due to psychotropic drugs in south Osaka during a 10-year period and discuss societal factors from a medical viewpoint. METHODS: Psychotropic drug-related deaths were retrospectively investigated based on the forensic postmortem data of 1,746 decedents in 2005-2014, and we excluded cases in which stimulant drugs were detected. Of these, 133 cases (7.6%) were found to be psychotropic drug-related deaths and were analyzed. RESULTS: Psychotropic drug-related deaths occurred in 78 males (59%; age range, 14-95 years) and 55 females (41%; 20-84 years). The direct cause of death was acute drug intoxication in many cases, and of these, acute combined drug intoxication due to the use of multiple drugs accounted for 76% of the deaths. Most of these victims were found to have gastrointestinal and cardiovascular diseases. Cases of psychotropic drug-related deaths had especially poor medical conditions. In addition, tests were positive for blood alcohol in 23% of the cases. CONCLUSION: The descriptive results revealed several factors that may be related to psychotropic drug-related deaths. To prevent drug abuse, several factors were deemed to be important, including improvements in the medical state of an individual, the avoidance of social isolation, and from a medical standpoint, the management of prescription drugs by medical personnel.

Virtual computed tomography morphometry of the patella for estimation of sex using postmortem Japanese adult data in forensic identification.

In forensic anthropological identification of human remains and single bones, computed tomography (CT) data analysis facilitates volumetric and radiographic density analyses, and a recently developed automated analysis system markedly improved the performance, accuracy, and reproducibility of three-dimensional (3-D) reconstruction. The present study aimed to investigate virtual CT morphometry of the patella for the estimation of sex using postmortem CT data of forensic autopsy cases of Japanese individuals aged ≥18 years (total n=220; 110 males and 110 females; estimated postmortem interval <88h), especially with regard to the efficacy of 3-D bone volumetry. Sex-related differences were detected for all parameters (males>females; p<0.0001), but the differences were the most notable for bone mass volume; the estimated cut-off values (cm3) for discriminating males and females were 20.35 with a sensitivity and specificity of 0.85 and 0.91 for the left side and 19.96 with a sensitivity and specificity of 0.83 and 0.92 for the right side, respectively. The mean CT value showed an age-dependent decrease and was particularly low in females aged >60years. These findings indicate the efficacy of virtual CT morphometry of the patella using an automated analyzer for sex estimation.

Toxicological and Biochemical Analyses of an Autopsy Case Involving Oral Overdose of Multiple Antidiabetic and Antihypertensive Drugs.

Oral antidiabetics can cause fatal hypoglycemia; although they can be chemically identified and quantified, biochemical investigations are important for assessing the biological consequences of an overdose. Such cases of overdose involving oral antidiabetics may involve other drugs for treating lifestyle-related diseases, particularly antihypertensives. Here, we report a toxicological and biochemical investigation of drugs and biochemical profiles in a fatal overdose involving multiple oral antidiabetics and antihypertensives. A 55-year-old woman died about 2 days after the ingestion of around 110 tablets of antidiabetics and antihypertensives that had been prescribed for her husband. A forensic autopsy and histological analysis demonstrated no evident pathology as the cause of death. A toxicological analysis suggested hypoglycemia and an overdose of antihypertensives as well as the retention of antidiabetics and diuretics in the pericardial fluid. A relatively low pericardial amlodipine concentration was observed, which may have been the result of its long half-life (slower distribution and reduction rate) and/or possible affinity with the myocardium. In addition, a biochemical analysis indicated hypoglycemia, without increased serum insulin and C-peptide, but with increased glucagon levels, as the possible influence of glibenclamide overdose. These observations suggest the usefulness of a combination of toxicological and biochemical analyses in postmortem investigations involving a fatal overdose of such drugs.

Biodistribution of diphenhydramine in reproductive organs in an overdose case.

Motion sickness medications such as Travelmin® prescribed in Japan include diphenhydramine (DPH), dyphylline, diphenidol, and/or caffeine. Herein, we report a patient who died due to rhabdomyolysis after ingesting a DPH containing motion sickness medication. A Japanese male in his 30 s reported missing after going out for a drive early in the morning was found dead in his car in the evening of the same day. An autopsy showed moderate edema, congestion, and several petechiae in both lungs. The brain was congested and edematous with no atherosclerosis of cerebral arteries. The prostate and both testes were slightly edematous. Gastric contents included approximately 15 mL of dark-brown fluid without tablets or food residue. Toxicological examination showed that blood DPH levels in all tissues were between 4.90 and 7.27 µg/mL, which represented toxic to lethal levels. DPH (µg/mL) levels were approximately 3-9 times higher in the prostate (73.42) and testes (left, 28.23; right, 30.09) than those in all regions of the brain (range 7.75-12.33). Blood dyphylline, diphenidol and caffeine levels in reproductive organs reached high, but not toxic levels. In conclusion, DPH, dyphylline, diphenidol, and caffeine levels were higher in reproductive organs such as the prostate and testes than in the central nervous system and heart. As we determined in this case, motion sickness medications might accumulate in reproductive organs. Thus, further examination of tissue biodistribution of DPH, dyphylline, diphenidol, and caffeine is necessary to assess their potential long-term effects in these sites.

Usefulness of postmortem biochemistry in identification of ketosis: Diagnosis of ketoacidosis at the onset of autoimmune type 1 diabetes in an autopsy case with cold exposure and malnutrition.

A severely malnourished, Japanese female in her twenties was found dead in her apartment. On autopsy, most of the findings from the internal examination were suggestive of hypothermia. Postmortem biochemistry, however, showed severely increased levels of glycated hemoglobin (HbA1c) and blood and urine glucose levels. Levels of acetone, 3-hydroxybutyric acid, and acetoacetate in various body fluids were also highly increased, indicating ketosis. The serum insulin and c-peptide levels were severely low, and subsequent testing was positive for anti-GAD antibodies. Immunohistochemical examination of the pancreatic islet cells revealed few insulin-positive cells but many glucagon-positive cells on staining. Furthermore, slight invasion of CD8-positive lymphocytes in the pancreatic islets of Langerhans was observed. Results of immunostaining of the pancreatic and bronchial epithelial tissues were partly positive for the Influenza A virus. We concluded that severe ketoacidosis associated with rapid-onset hyperglycemia due to autoimmune type 1 diabetes (AT1D) had occurred shortly before death. However, the ketosis was accompanied by hypothermia and malnutrition as well as diabetic ketoacidosis (DKA). Therefore, we retrospectively collected biochemical data on cases of hypothermia and malnutrition and compared them with the present case. Serum glucose, acetone, 3-hydroxybutyric acid, and acetoacetic acid can be used for screening and diagnosis to distinguish DKA from ketosis due to hypothermia and malnutrition. Therefore, in the present case, we diagnosed that the natural cause of death was due to AT1D. In conclusion, screening investigations for relevant biochemical markers can provide essential information for the diagnosis of metabolic disturbances, which fail to demonstrate characteristic autopsy findings.

Evaluation of Postmortem Drug Concentrations in Bile Compared with Blood and Urine in Forensic Autopsy Cases.

For drug screening and pharmaco-/toxicokinetic analysis, bile as a major drug excretion route in addition to urine may be used in forensic autopsy cases; however, there are limited published data on correlations between bile and blood or urine drug concentrations. The present study retrospectively investigated drug concentrations in bile, compared with blood and urine concentrations, reviewing forensic autopsy cases during 6 years (January 2009-December 2014). Drugs were analyzed using automated gas chromatography-mass spectrometry following solid-liquid phase extraction. Compared with peripheral blood concentrations, bile concentrations were higher for most drugs; however, caffeine concentrations were similar. Bile concentrations were mostly lower than urine concentrations for amphetamines, caffeine and methylephedrine, but were usually similar to or higher for other drugs. Significant correlations were detected between bile and peripheral blood concentrations for amphetamines, several cold remedies, phenobarbital, phenothiazine derivatives and diazepam, as well as between bile and urine concentrations for amphetamines, caffeine, diphenhydramine, phenobarbital and promethazine derivatives. These findings suggest that bile can provide supplemental data useful in routine forensic toxicology, for the spectrum of drugs mentioned above, as well as for investigating pharmaco-/toxicokinetics and postmortem redistribution when analyzed in combination with drug concentrations at other sites.

Possible application of CT morphometry of the calcaneus and talus in forensic anthropological identification.

Computed tomography (CT) data provide information for volumetric and radiographic density analysis. The present study investigated the application of virtual CT volumetry of the tarsal bones to estimation of the sex, stature, and body weight using postmortem CT (PMCT) data of forensic autopsy cases. Three-dimensional (3D) images of the bilateral foot bones of intact Japanese subjects after adolescence (age ≥ 15 years, n = 179, 100 males and 79 females) were reconstructed on an automated CT image analyzer system. Measured parameters were mass volume, mean CT value (HU), and total CT value of the talus and calcaneus. Mean CT values of these bones showed age-dependent decreases in elderly subjects over 60 years of age for both sexes, with significant sex-related differences especially in the elderly. The mass volumes and total CT values of the talus and calcaneus showed significant sex-related differences, and also moderate correlations with body height and weight for bilateral bones in all cases (r = 0.58-0.78, p < 0.0001); however, the correlations of these parameters of the female talus with body weight were insufficient (r = 0.41-0.61, p < 0.0001). These observations indicate the applicability of virtual CT morphometry of the talus and calcaneus using an automated analyzer to estimate the sex and stature in forensic identification; however, greater variations should be considered in body weight estimations of females.

Evaluation of postmortem drug concentrations in cerebrospinal fluid compared with blood and pericardial fluid.

In forensic toxicology, body fluids are important materials not only as alternatives to blood but also for investigation of postmortem drug redistributions and pharmaco-/toxicokinetic analysis; however, there are limited data on postmortem drug distributions in cerebrospinal fluid (CSF). The present study reviewed toxicological data of autopsy cases (n=103), in which drugs were detected in CSF using gas chromatography/mass spectrometry (GC/MS), to investigate drug concentrations in CSF, compared with blood and pericardial fluid (PCF) concentrations. Oral/injected amphetamines (n=23) showed similar CSF and blood/PCF concentrations with partly lower CSF concentrations (about ×0.5-1.1). CSF concentrations of the venous anesthetic midazolam (n=7) were lower with poor correlations. Oral caffeine (n=15), acetaminophen (n=7), chlorpheniramine (n=6), dihydrocodeine (n=6), and phenobarbital (n=21) showed equivalent to lower CSF concentrations (about ×0.2-1.2), compared with blood and PCF concentrations; however, CSF phenobarbital concentrations were high in a fatal intoxication case. CSF concentrations of phenothiazine derivatives (n=29) were markedly lower (about ×0.1) than blood/PCF concentrations. The distribution of the local anesthetic lidocaine used in critical medical care (n=49) markedly varied by case. These findings suggest that CSF is useful in routine forensic toxicology as an alternative to blood as well as for investigating pharmaco-/toxicokinetics and postmortem redistributions.

Virtual CT morphometry of lower limb long bones for estimation of the sex and stature using postmortem Japanese adult data in forensic identification.

The application of computed tomography (CT) is useful for the documentation of whole-body anatomical data on routine autopsy, virtual reconstruction of skeletal structure, objective measurements, and reassessment by repetitive analyses. In addition, CT data processing facilitates volumetric and radiographic density analyses. Furthermore, a recently developed automated analysis system markedly improved the performance and accuracy of three-dimensional (3D) reconstruction. The present study investigated virtual CT morphometry of lower limb long bones, including the femur, tibia, fibula, and first metatarsus, to estimate the sex and stature using postmortem CT data of forensic autopsy cases of Japanese over 19 years of age (total n = 259, 150 males and 109 females). Bone mass volumes, lengths, and total CT attenuation values of bilateral femurs, tibias, and fibulas correlated with the stature; however, the mean CT attenuation (HU) values showed age-dependent decreases. Correlations with the stature were similar for the lengths and mass volumes of the femur, tibia, and fibula (r = 0.77-0.85) but were higher for the mass volume of the first metatarsus (r = 0.77 for right and r = 0.58 for left). In addition, the ratio of the bone volume to the length of each bone showed the most significant sex-related differences (males > females with accuracy of 75.8-98.1 %). These findings indicate the usefulness of virtual CT morphometry of individual lower limb long bones, including volumetry, to estimate the sex and stature in identification.

Efficacy of drug screening in forensic autopsy: retrospective investigation of routine toxicological findings.

Toxicological analysis is indispensable in forensic autopsy laboratories, but often depends on the limitations of individual institutions. The present study reviewed routine drug screening data of forensic autopsy cases (n=2996) during an 18.5-year period (January 1996-June 2014) at our institute to examine the efficacy of the procedures and findings in autopsy diagnosis and interpretation. Drug screening was performed using on-site immunoassay screening devices and gas chromatography/mass spectrometry (GC/MS) in all cases, followed by re-examination using GC/MS and liquid chromatography/tandem mass spectrometry (LC/MS/MS) at a cooperating institute in specific cases in the last 4 years. GC/MS detected drugs in 486 cases (16.2%), including amphetamines (n=160), major tranquilizers (n=72), minor tranquilizers (n=294), antidepressants (n=21), cold remedies (n=77), and other drugs (n=19). Among these cases, fatal intoxication (n=123) involved amphetamines (n=73), major tranquilizers (n=37), minor tranquilizers (n=86), antidepressants (n=3), and cold remedies (n=9); most cases involved self-administration, alleged suicide and accidental overdose, while homicide was not included. These drugs were also identified in other manners of death, including homicide (n=40/372), suicide (n=34/226), accidental falls (n=27/129), and natural death (n=72/514). In these cases, on-site immunoassay screening of drugs of abuse showed negative findings in 2440 cases (81.4% in all cases), while GC/MS detected other drugs in 218 cases (7.3% in all cases), including several antipsychotic drugs, acetaminophen and salicylic acid. Further analysis using LC/MS/MS detected low concentrations of benzodiazepines in 32 cases, and also anti-diabetic and hypertensive drugs in a case of fatal abuse. These observations indicate the efficacy of systematic routine toxicological analysis to investigate not only the cause of death but also the background of fatalities in forensic autopsy. The provision of extensive drug screening is needed for forensic and social risk management, considering the marked diversity of medical and illicit drugs.

Postmortem CT morphometry with a proposal of novel parameters for sex discrimination of the mandible using Japanese adult data.

Major human sex differences in the mandible after adolescence include the overall size as well as the shape of the chin and mandibular angle; however, objective interpretation of discrimination accuracy is difficult for these morphological indicators. The present study investigated measurements of the mandible for sex discrimination using postmortem CT morphometry in forensic autopsy cases of Japanese subjects after adolescence (age>16 years; male, n=116, and female, n=106), including the proposal of novel parameters representing the overall mandibular size and shape. The distance between the gnathion and condylus (gn-cdl), and bigonial width (go-go), as well as the angle formed by bilateral gn-cdl lines (Agn-cdl), correlated with bicondylar breadth (cdl-cdl), independent of the body height, showing no significant sex difference. The distance from the gn to the cdl-cdl line (oblique length), the ratio of Agn-cdl to cdl-cdl, and the oblique triangular area formed by bilateral gn-cdl and cdl-cdl lines (Δobl), which were proposed as indicators of chin protrusion, showed significant sex differences (p<0.001). Overall sensitivity and specificity at respective discriminating points for sex estimation were 0.72 and 0.78 at 105.0mm for the oblique length, 0.73 and 0.83 at 0.49 for the Agn-cdl to cdl-cdl ratio, and 0.82 and 0.78 at 643 mm(2) for Δobl; the efficacy for females was greater in younger subjects. Although these parameters weakly depended on the body height (p<0.0001), the correlations were insufficient for stature estimation. These findings suggest the efficacy of CT morphometry of the mandible for sex discrimination with quantitative assessment.

Contribution of forensic autopsy to scene reconstruction in mass fire casualties: a case of alleged arson on a floor consisting of small compartments in a building.

A fire is an important cause of mass disasters, involving various forensic issues. Before dawn on an early morning, 16 male visitors in their twenties to sixties were killed in a possibly incendiary fire at a 'private video parlor' consisting of small compartments in a building. The main causes of death as determined by forensic autopsy were acute carbon monoxide (CO) intoxication for all of the 15 found-dead victims, and hypoxic-ischemic encephalopathy following acute CO intoxication for a victim who died in hospital. Burns were mild (<20% of body surface) in most victims, except for three victims found between the entrance and the estimated fire-outbreak site; thus, identification was completed without difficulty, supported by DNA analysis. Blood carboxyhemoglobin saturation (COHb) was higher for victims found dead in the inner area. Blood cyanide levels were sublethal, moderately correlated to COHb, but were higher in victims found around the estimated fire-outbreak site. There was no evidence of thinner, alcohol or drug abuse, or an attack of disease as a possible cause of an accidental fire outbreak. These observations contribute to evidence-based reconstruction of the fire disaster, and suggest how deaths could have been prevented by appropriate disaster measures.

Postmortem CT morphometry of great vessels with regard to the cause of death for investigating terminal circulatory status in forensic autopsy.

Postmortem CT (PM-CT) is useful to investigate the viscera in situ before opening the body cavities at autopsy. The present study involved a virtual morphometric analysis of thoracic and abdominal great vessels with regard to the cause of death as a possible index of terminal circulatory status in forensic autopsy cases, using PM-CT data of forensic autopsy cases within 3 days postmortem (n = 93). Perimeters and cross-sectional areas of the aorta and vena cava depended on the age and/or gender of subjects; however, when the vessel flattening index (vFI) was calculated as the ratio of the cross-sectional area (a) to the estimated circle area having the same perimeter (l), using the formula vFI = 4πa/l(2), the vFI showed distinct differences among the causes of death without significant postmortem time dependence. The index was low for each vessel in fatal bleeding, while the vFI of the abdominal aorta and inferior vena cava was low in hyperthermia (heatstroke), but higher in drowning, hypothermia (cold exposure) and sudden cardiac death. These CT findings provide quantitative data as supplementary indicators to reinforce autopsy findings for interpreting terminal circulatory status.

Postmortem volumetric CT data analysis of pulmonary air/gas content with regard to the cause of death for investigating terminal respiratory function in forensic autopsy.

Postmortem CT (PMCT) is useful to investigate air/gas distribution and content in body cavities and viscera. The present study investigated the procedure to estimate total lung air/gas content and aeration ratio as possible indices of terminal respiratory function, using three-dimensional (3-D) PMCT data analysis of forensic autopsy cases without putrefactive gas formation (within 3 days postmortem, n=75), and analyzed the volumetric data with regard to the cause of death. When 3-D bilateral lung images were reconstructed using an image analyzer, combined lung volume was larger in drowning (n=12) than in alcohol/sedative-hypnotic intoxication (n=8) and sudden cardiac death (SCD; n=10), and intermediate in other cases, including mechanical asphyxiation (n=12), fire fatalities due to burns (n=6) and carbon monoxide intoxication (n=7), fatal methamphetamine abuse (n=7), hyperthermia (heatstroke; n=6) and fatal hypothermia (cold exposure; n=7). Air/gas content of the lung as detected using HU interval between -2000 and -400 ('effective' lung aeration areas) and between -2000 and -191 (total lung aeration areas) as well as the ratios to total lung volume ('effective' and total lung aeration ratios, respectively) was higher in mechanical asphyxiation, drowning, fatal burns and hypothermia (cold exposure) than in SCD, and was intermediate in other cases. 'Effective' and total lung aeration ratios may be useful for comparisons between specific causes of death to discriminate between hypothermia (cold exposure) and drug intoxication, and between SCD and other causes of death, respectively. These findings provide interesting insights into potential efficacy of PMCT data analyses of lung volume and CT density as well as lung air/gas content and aeration ratio with regard to the cause of death, as possible indicators of terminal respiratory function, as part of virtual autopsy of the viscera in situ.

Postmortem virtual volumetry of the heart and lung in situ using CT data for investigating terminal cardiopulmonary pathophysiology in forensic autopsy.

Postmortem CT (PM-CT) is useful to investigate the viscera in situ before opening the body cavity at autopsy. The present study investigated heart and lung volumes in situ with regard to the cause of death as possible indexes of terminal cardiopulmonary dysfunction by means of PM-CT data analysis of forensic autopsy cases within 3 days postmortem (n=70). Estimated heart volume was larger in sudden cardiac death (SCD; n=10) and fatal methamphetamine abuse (n=5) than in other groups, including mechanical asphyxiation (n=12), drowning (n=11), acute alcohol/sedative-hypnotic intoxication (n=8), fire fatality (n=12), hyperthermia (heatstroke; n=6) and fatal hypothermia (cold exposure; n=6). Estimated combined lung volume was larger in drowning, smaller in fire fatality due to carbon monoxide intoxication and SCD, and intermediate in other groups. Volume ratio of the lung to heart was higher in drowning, lower in SCD, and intermediate or varied in other groups; high and low ratios can indicate predominant/antecedent pulmonary and cardiac dysfunctions, respectively. These findings provide quantitative data that are not available at conventional autopsy or by routine two-dimensional CT morphology to assess three-dimensional gross heart and lung morphologies for interpreting terminal cardiopulmonary pathophysiology, detecting significant difference between SCD and other causes of death, especially mechanical asphyxiation and drowning.

Efficacy of automated three-dimensional image reconstruction of the femur from postmortem computed tomography data in morphometry for victim identification.

Besides conventional radiology, postmortem computed tomography (PM-CT) is nowadays widely used for victim identification in forensic routines to detect anatomical characteristics and specific pathologies as well as to estimate the stature and sex. A major advantage of PM-CT is virtual reconstruction of skeletal structures independent of the status of recovered remains. The present study investigated the efficacy of a recently provided automated analyzer to reconstruct three-dimensional (3-D) images using CT data for skeletal morphometry, measuring the whole bone mass volume of the femur (60 bones in 30 cases) as an index of reproducibility. Manual cursoring could reconstruct bilateral femurs with high reproducibility, showing mass volume fluctuations by repetition and between two independent observers of 0.2-2.1% and 3.5-6.7%, respectively, partly depending on the data analysis system, but was time-consuming, while automated reconstruction was very rapid and highly reproducible virtually without detectable fluctuation; there was a high correlation between bone mass volumes reconstructed by manual and automated procedures (r=0.9976, p<0.0001). The reproducibility of the automated procedure was 98.64-100.81% in 5 cases scanned twice under the same CT conditions. Preliminary analysis showed a substantial correlation of the whole femur mass volume with the body height and a significant sex-related difference in the femur mass volume/body height ratio (males>females). These findings indicate the accuracy and practical feasibility of the automated procedure to reconstruct single bone 3-D CT images for virtual skeletal morphometry in victim identification.