Journal of Forensic Radiology and Imaging最新文献

Postmortem computed tomography (PMCT) provides significant information with regard to specific forensic questions for the determination of manner and cause of death. After the external examination of a body, PMCT appears to be a valuable tool for imaging-based decision making whether conducting an autopsy is necessary. Within that domain of application, a series of ten cases is presented to qualitatively highlight the current state of the art and remaining problems. PMCT combined with detailed external examination of the body and toxicological tests can satisfactorily answer the leading forensic questions of some cases, like the validation of the victim's identity and the presence of foreign bodies and determine the cause and manner of death. By absence of suspected trauma or third party violence during the scene investigation and the external examination of a corpse, PMCT can add more validity to these assumptions or contradict those revealing unexpected findings. Thus, a conventional medicolegal autopsy can be avoided as all relevant forensic questions are answered, which is also time and cost consuming. However, reliable evaluation of relevant head and cervical trauma, strangulation, infection and sepsis, metabolic disorders, intoxication and neuroreflex deaths keeps evading a purely PMCT-based approach.

Background

Gunshot injuries are frequent and may result in retained ballistic projectiles or fragments, this is why it is crucial to determinate the ferromagnetic property of retained projectiles if an MRI is considered.

Purpose

The goal of this ex vivo study was to determine if Dual-Energy Computed Tomography (DECT) can discriminate ferromagnetic bullets from non-ferromagnetic bullets.

Material and Methods

Twelve different bullets, placed in the center of the scanner on a gelatin phantom, underwent DECT evaluation. These projectiles were both ancient bullets from the 19Th century (eg. 8 mm 1890 ECP) and recent bullets from the late 20th century (eg. 9 mm Lüger; 7.92 mm Mauser; 7 mm sport carabin). Two independent radiologists who were blinded to the properties of bullets performed all measurement on an external workstation with extended CT scale. Regions of interest (ROI) were placed in the core of each projectile. From these data, a dual-energy index (DEI) was calculated. A bootstrap method with a p value of less than 0.05 was used to demote statistical significance.

Results

Five bullets were ferromagnetic and seven were non-ferromagnetic. The DEI calculated were significantly (p < 0.05) different between the ferromagnetic and non-ferromagnetic projectiles. There were no significant difference (p > 0.05) for intrareader and interreader agreement analysis.

Conclusion

DECT, found a difference between this ferromagnetic and non-ferromagnetic bullets samples using an extended HU, but because of several limitations in this study there is no cut-off DEI value to differentiate these two groups of bullets.

Objective

With a specific focus on Italy, the aim of this paper was to assess the development of forensic imaging techniques, to determine which techniques have had a larger diffusion, and to identify the most relevant field of application.

Materials and methods

An online literature search was performed to identify Italian publications on forensic imaging between 1956 and February of 2018. For each publication included in the analysis, the following data were annotated: title and abstract, year of publication, type of article, and number and type of subjects examined. The selected publications were also categorized based on imaging modalities and the forensic field of investigation.

Results

A total of 44 Italian publications were included in the study. Publications of forensic imaging have increased in the last years. More than half of all manuscripts were related to post-mortem investigations (31/44; 70%). The majority of all post-mortem publications were focused on the documentation of injury or disease followed by identification and age estimation category (5/44; 11%). In cases of unnatural death, the principle issue of research was gunshot wounds, followed by asphyxia and drowning. The most commonly used imaging modality was computed tomography (CT).

Conclusions

The results of this study showed an increase of forensic imaging in Italy in the last years. However, a review of the literature demonstrated that imaging techniques are not yet exhaustively adopted by the Italian forensic community, and that further research is needed to provide information about the accuracy of forensic imaging techniques with respect to autopsy.

Introduction

In the mandible, the gonial angle value is used to ascertain the age and gender differences for the forensic and anthropological purposes. Lots of research is being conducted on this topic, but the result of one contradicts the other.

Methods

We tested the hypothesis of a relationship between gonial angle and the age, gender and dental status using lateral cephalograms and orthopantomograms from 242 subjects aged between 6 and 80 years. The Paired t-test was used to assess the difference in the gonial angle between the radiographs and independent samples t-test was used to assess the difference between male and female samples. ANOVA test with Post hoc multiple comparisons were used to assess the difference in gonial angle among the age subgroups in both the radiographs. The p-value <0.05 was considered for statistical significance.

Results

There was significant difference in the gonial angle values between lateral cephalograms and OPG. The mean difference was greater on the left side (1.77° ± 3.57) than on the right side of the mandible (1.54° ± 3.00). A significant gender difference in gonial angle was observed in lateral cephalogram. The dentulous group had significantly higher gonial angle values than the edentulous group. Only OPG gonial angles showed significant difference among age groups.

Conclusion

The gonial angle values in orthopantomogram and lateral cephalogram differ significantly. The gonial angle from orthopantomogram can be used for age estimation and that from lateral cephalogram can be used for gender determination.

A man in his fifties was found dead in his bed. Using postmortem CT, the frontal sinus wall was seen to have been destroyed and a subcutaneous / intra-cranial mass-like lesion was detected. Postmortem blood biochemical examination demonstrated high values of urea nitrogen, c-reactive protein, procalcitonin, and precepsin, which were thought to be due to sepsis. Needle aspiration showed reddish viscous fluid, and the presence of Klebsiella oxytoca was confirmed by culture inspection. Based on these results, Pott's puffy tumor with intracranial empyema, and dehydration with sepsis in the agonal period was assessed as the cause of death. Using autopsy evaluation, it was possible to come to a concrete conclusion, but a minimally invasive autopsy might be an alternative approach to investigate the cause of death.