Virtopsy: postmortem imaging of the human heart in situ using MSCT and MRI

The rapid further development of computed tomography (CT) and magnetic resonance imaging (MRI) induced the idea to use these techniques for postmortem documentation of forensic findings. Until now, only a few institutes of forensic medicine have acquired experience in postmortem cross-sectional imaging. Protocols, image interpretation and visualization have to be adapted to the postmortem conditions. Especially, postmortem alterations, such as putrefaction and livores, different temperature of the corpse and the loss of the circulation are a challenge for the imaging process and interpretation. Advantages of postmortem imaging are the higher exposure and resolution available in CT when there is no concern for biologic effects of ionizing radiation, and the lack of cardiac motion artifacts during scanning. CT and MRI may become useful tools for postmortem documentation in forensic medicine. In Bern, 80 human corpses underwent postmortem imaging by CT and MRI prior to traditional autopsy until the month of August 2003. Here, we describe the imaging appearance of postmortem alterations--internal livores, putrefaction, postmortem clotting--and distinguish them from the forensic findings of the heart, such as calcification, endocarditis, myocardial infarction, myocardial scarring, injury and other morphological alterations.     

Forensic interpretation of Y-chromosomal DNA mixtures

The mathematical concept previously introduced for the forensic interpretation of DNA mixtures using non-associated genetic markers has been adapted to the assessment of haplotypes. Such calculus is required, for example, when Y-chromosomal markers are used in forensics. In addition to outlining the general mathematical framework, we devise two approaches to its practical computational implementation, involving either the inclusion-exclusion principle of probability theory or a recursion in the number of unknown contributors invoked. The two approaches scale differently, depending upon the complexity of the case and the diversity of the markers used. The performance of Y-chromosomal microsatellites (Y-STRs) as a means of trace donor discrimination has been assessed by simulation, using the derived formulas. Based upon data from the Y-chromosomal Haplotype Reference Database (YHRD), the exclusion chance of a non-contributor is shown to vary between 95% in the case of two contributors, and 70% for five contributors. With only one additional contributor, half of all contributing suspects would yield a log-likelihood ratio in favour of donorship of 1.61 or higher, although the median drops to 0.66 with four additional contributors. It must be emphasised that these estimates of the discriminatory power of Y-STRs are likely to be conservative since the simulations involved only haplotypes known to occur in YHRD.     

Pneumomediastinum and soft tissue emphysema of the neck in postmortem CT and MRI; a new vital sign in hanging?

Spontaneous pneumomediastinum commonly occurs in healthy young men or parturient women in whom an increased intra-alveolar pressure (Valsalva maneuver, asthma, cough, emesis) leads to the rupture of the marginal pulmonary alveoli. The air ascends along the bronchi to the mediastinum and the subcutaneous space of the neck, causing cervico-fascial subcutaneous emphysema in 70-90% of cases. Ninety-five forensic cases, including five cases of hanging, were examined using postmortem multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) prior to autopsy until December 2003. This paper describes the findings of pneumomediastinum and cervical emphysema in three of five cases of hanging. The mechanism of its formation is discussed based on these results and a review of the literature. In conclusion, when putrefaction gas can be excluded the findings of pneumomediastinum and cervical soft tissue emphysema serve as evidence of vitality of a hanged person. Postmortem cross-sectional imaging is considered a useful visualization tool for emphysema, with a great potential for examination and documentation.     

Fatal steamer accident; blunt force injuries and drowning in post-mortem MSCT and MRI

Steamer accidents, through contact with the bucket wheel, are very seldom today. No publication of such a kind of fatal accident could be found in literature. We present the case of a fatal steamer accident, in which the findings of a blunt traumatization of a person by the ship was completely documented by post-mortem combined multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) examinations. A rupture of the aorta was detected using both radiological methods without use of radiopaque material. Radiological examination revealed a comminuted fracture of the thorax vertebrae at the same level as the aortic rupture. Injuries of the soft tissues of the back, caused by the bucket wheel of the steamer, were also diagnosed. In addition to the signs of blunt force trauma the findings of drowning such as an over inflation of the lungs, fluid in the stomach and duodenum were revealed. Furthermore, algological analysis detected diatoms in the lung tissue and blood from the left heart. Therefore, the cause of death was considered being a combination of fatal hemorrhage, caused by the aortic rupture, and drowning. We conclude that virtual autopsy using combined post-mortem MSCT and MRI is a useful tool for documentation, visualisation and analysis of the findings of blunt force trauma and drowning with a large potential in forensic medicine.     

Measurement Properties of the Communities That Care<Superscript>®</Superscript> Youth Survey Across Demographic Groups

Prevention science has produced information about risk and protective factors that predict adolescent drug use and related problem behaviors. This paper investigates the Communities That Care Youth Survey that measures multiple risk and protective factors. Using a sample of 172,628 students who participated in surveys administered in seven states in 1998, analyses were conducted to test the factor structure of these risk and protective factors and to test the equivalence of the factor models across five racial/ethnic groups (African Americans, Asians or Pacific Islanders, Caucasians, Hispanic Americans, and Native Americans), four grade levels (6th, 8th, 10th, and 12th) and both gender groups. Results support the construct validity of the surveys risk and protective factor scales and indicate that the measures are equally reliable across males and females and five racial/ethnic groups. Implications of these findings for science-based prevention planning are discussed.     

Police attitudes toward the utilization of civilian employees

Given that the disposition of patrol officers significantly affect the implementation of policy, the attitudes of patrolmen toward utilization of civilian personnel in two department differing in their rate of civilianization, were compared in this study. Based on a random sample, consisting of approximately 25% of the patrolmen from each department, attitudes toward each of three examined aspects of civilianzation were more positive among officers from the more civilianized department. After controlling for socioeconomic variables, it was also determined that younger, more educated and less experienced patrolmen, respectively, held motte positive belief about civilian usage.     

The epidemiology of female rape victims who seek immediate medical care: temporal trends in the incidence of sexual assault and acquaintance rape

Women who seek medical care following sexual assault are usually evaluated and treated in an emergency department (ED). Therefore, EDs can be an important source of sexual assault surveillance data. The authors compared the incidence of sexual assault presenting for emergency care in a single county during July to November of 1974 and 1991. Participants included all female sexual assault victims aged 14 and older who presented for ED evaluation. Treating physicians prospectively collected data using standardized forms. The z statistic was used to compare sexual assault incidence. There was a 60% increase in the incidence of sexual assault victims presenting for emergency care in 1991 compared to 1974, primarily due to an increase in the incidence of women presenting to the ED after rapes by known assailants. In contrast, the annual incidence of reported stranger assaults was similar in the two study years.     

Differences in attitudes toward gays and lesbians among criminal justice and non-criminal justice majors

The criminal justice system is supposed to protect and serve all members of the community equally; therefore, any prejudicial attitudes harbored by criminal justice students may negatively impact their job performance as future justice professionals. Four hundred and eighty-four students at a large Midwestern university were surveyed on their views toward gay and lesbian persons and issues. The responses of criminal justice majors were compared to the responses of students majoring in other fields. Criminal justice majors tended to have more negative views of gays and lesbians than students in other majors. However, there was not a significant difference between the two groups of students in their willingness to extend rights to and socialize with gay and lesbian individuals.