Forensic Imaging最新文献

Background

Age estimation of unidentified human remains is an essential for establishing the biological profile of unidentified human remains. Previous studies have investigated the value linear measurements of the frontal sinus for age estimation while the value of two-dimensional (2D) geometric morphometric measurements have not been explored for this purpose.

Objective

This study aims to evaluate the morphological variation of frontal sinus among adults Malaysian for age estimation using 2D geometric morphometric methods.

Methods

Lateral skull radiographs of 453 adult Malaysians, comprising 151 young adults (20–39 years old), 150 middle-aged adults (40–59 years old) and 152 old adults (60–79 years old), were retrieved retrospectively. Eight 2D landmarks were applied to digitalized radiographs using TPSDig2 software. 2D geometric morphometric analysis was performed by MorphoJ software.

Results

Procrustes ANOVA revealed no significant differences in shape and size (p-value > 0.05) of frontal sinus between the three age groups. However, Canonical Variate Analysis showed significant differences for Mahalanobis and Procrustes distances (p-value < 0.05) between young and old adult groups. Discriminant Function Analysis after cross-validation demonstrated an age classification accuracy of 53.5 %.

Conclusion

The study suggests that 2D geometric morphometric analysis of the frontal sinus cannot be reliably used to estimate the age of an unknown Malaysian individual.

Objectives

Postmortem computed tomography (PMCT) is widely used in forensic cause-of-death investigations, and 3D volume rendering is commonly employed for visualizing PMCT data. However, no studies have investigated the effectiveness of organ-selective 3D volume rendering for detection of organ injuries such as liver and heart. This study aimed to assess whether selective volume rendering could enhance the detectability of organ damage that is generally difficult to observe in 2DCT images.

Material and methods

Using 22 selected cases of liver or heart injury, the detectability of the injury in 2DCT images and selective volume-rendered images was compared with actual autopsy findings.

Results

Among 15 cases of liver injury confirmed at autopsy, 2DCT imaging detected two, whereas selective volume-rendered imaging detected one. Furthermore, among 17 cases of cardiac injury, 2DCT imaging detected two, whereas selective volume-rendered imaging detected four. Thus, a small proportion of liver and heart injury cases were detectable using 2DCT imaging or selective volume rendering. In all cases where selective volume rendering identified an injury, the injury was not identified by radiologist interpretation of the 2DCT images, although a review of the 2DCT images did allow identification of the injury when corroborated by the findings of selective volume rendering. One additional case demonstrated the usefulness of selective volume rendering for estimation of puncture wound direction.

Conclusions

Although selective volume rendering has seldom been effective in detecting heart or liver damage, organ-selective volume rendering may provide clues for detection of injuries that are often overlooked in 2DCT images alone.

A man in his 40s was run over by a wheel loader that was slowly backing up behind him late at night at a construction site. The driver stopped when he saw a man lying on the ground after being hit by the right rear and front wheels. Pre-autopsy postmortem computed tomography (PMCT) revealed that a portion of the left lung extended from the left axilla to the subcutaneous area of the upper arm. An oval mass with a point density of 40–60 Hounsfield units was found in the peripheral lung tissue of the left upper arm. Autopsy findings revealed extensive décollement from the left upper arm to the forearm, with a disconnected heart in the interstitial space and lung tissue straying to the central side.

There are no reports of thoracic organs straying into the upper arm subcutaneously, and when reading forensic PMCT images prior to autopsy, not only crush injury but also organs dislocation should be looked for carefully if the organ is absent.

Background

Tuberculosis remains one of the leading causes of death from a single infectious agent, second only to COVID-19, as stated by WHO Global Tuberculosis Report 2021. Tuberculosis can present as parenchymal lesions, vascular lesions, mediastinal lesions, airway lesions, pleural lesions and chest wall lesions. One such presentation is the development of secondary spontaneous pneumothorax.

Case report

A 32-year-old male, found lying in unresponsive state was taken to Emergency department, where he was declared as brought dead. The autopsy revealed diffuse granular lesions on both lungs with purulent secretions. No evident emphysematous bullae or parenchymal breach or rib fractures were appreciable in macroscopic examination. Post mortem Computed tomography revealed unilateral spontaneous tension pneumothorax on the left side with compression of great vessels and mediastinal structures. Histopathological examination further confirmed disseminated tuberculosis in both lungs.

Conclusion

Deaths involving spontaneous secondary pneumothorax is so rare for clinicians that forensic pathologists are in a prime position for reporting such findings. In addition, PMCT plays an important role in diagnosing tension pneumothorax and the compression of mediastinal structures as compared to the traditional autopsy

Basilar artery entrapment secondary to fracture of the clivus is an extremely rare entity that is associated with high-energy head trauma. We report the first published example with postmortem computed tomography (CT) angiographic correlation with antemortem CT angiography findings, as well as macroscopic and histological confirmatory images. In this case, the head impact was secondary to a fall from a bar stool. Given how often head injuries are encountered in forensic pathology, it is possible that clivus fractures with vertebral or basilar artery entrapment are less rare than has previously been recognised. This entity warrants consideration in cases of non-immediate death following head trauma, especially where there is evidence of posterior circulation ischaemic injury. Where possible, postmortem CT angiography should be undertaken, with a view for further specialised dissection of the vertebral arteries and basilar artery where indicated.

Contemporary documentation of a car with bullet defects after a shooting incident can secure the usual tracks and gunshot residue, take photographs, and use trajectory rods and probes. Since the advent of the “XXL-CT -Scanner” (Fraunhofer Institute, Germany), we have wondered if the advantages of volume scanning CT, already noted for forensic pathology, could be applied to cars. To this end, we damaged a small 3D-printed car model with an electric drill and added CT -dense material with a soldering iron, simulating linearly configured defect morphologies with metal particles. This model was CT -scanned and the resulting data visualized to illustrate how these visualizations can support reconstructive visualization of trajectories. Performing a real XXL-CT scan of a bullet-riddled car requires extensive preparation, transportation, and other logistical measures that are costly and time-consuming. Nonetheless, we suggest that this is a worthwhile research direction to explore.

A specialized branch of medical imaging known as forensic radiology is employed in legal proceedings by forensic experts, doctors, pathologists, and anthropologists for the purpose of evaluation. In the realm of forensic medicine and toxicology, imaging technologies and procedures have the potential to be effective and strong instruments in resolving medicolegal cases. In addition to a brief history, this article also discusses the application of post-mortem imaging, its economic benefits, and its current status in India with respect to the global context. Radiography is still the choice of modality for identifying and locating foreign bodies at the time of death despite the increase in PMMR and PMCT.

The high number of unidentified bodies recorded in South Africa annually, combined with substantial heterogeneity within the population, necessitates that innovative forensic analysis methods be developed that incorporate variations from South African groups. Although sizeable three-dimensional (3D) scanning modalities exist in osteology and anthropology, developing new advanced methods and techniques involving 3D scanning for real-life forensic applications require that the accessibility, practicality, and, more importantly, accuracy of the methods be taken into consideration. To this end, this study aimed to assess the reliability of 3D surface scanning-based topographical and shape analysis comparison to gold standard micro-focus X-ray computed tomography (micro-XCT) reconstructions for estimating population affinity.

Forty-four adult crania were collected from the Pretoria Bone Collection (PBC), University of Pretoria, South Africa. Two sets of 3D reconstructions were acquired from each cranium, namely micro-XCT scans and 3D surface scans. Three-dimensional reconstructions and landmark datasets were acquired from both scanning modalities and compared using reproducibility testing, geometric discrepancies, and shape analysis.

The minimal geometric discrepancies observed between the reconstructions suggest that both modalities will provide similar shape landmarks datasets and can be used without compromising the accuracy of the analyses at term. The statistical findings showed similar population affinity-related mid-facial shape variations analyzed across both modalities using geometric morphometric methods (GMM).

Incorporating multiple 3D scanning modalities and advanced GMM into the existing biological profile estimation will allow South African forensic anthropologists to analyze shape-related skeletal variation in a more accurate and repeatable way and provide an efficient biological profile in forensic cases.

This paper presents guidance in the form of 10 basic rules for those embarking upon or running established postmortem computed tomography (PMCT) reporting services to consider adopting to assist reducing the risk of erroneous diagnosis of PMCT reporting particularly where remote reporting services are being operated or non-pathology practitioners are taking on enhanced roles and responsibilities within a PMCT service traditionally undertaken by autopsy pathologists.