Incidental occult gunshot wound detected by postmortem computed tomography

Post-mortem CT in the investigation of homicides

AIM

To investigate the reliability of post-mortem computed tomography (PMCT) in a case series of homicides involving blunt-force, sharp-force, and ballistic trauma.

MATERIALS AND METHODS

The study investigates 16 homicide cases that underwent PMCT before autopsy. Two radiologists assessed the PMCT examinations and the data were compared to the forensic pathology findings. Data were organised in broad categories: foreign bodies, external injuries, soft-tissue and organ injuries, fractures, air in cavities, fluid collections, random pathology, and wound track. Findings were organised by systems: head and neck, thorax, abdomen and pelvis, extremities. Cohen's kappa statistics were used to assess observer agreement.

RESULTS

Six gunshot-related homicides (37.5%), seven sharp-force-related homicides (43.75%), two blunt-force-related deaths (12.5%), and one homicide due to mechanical asphyxia (1.25%) were analysed. A total of 64 fractures were reported by the pathologists, 67 by radiologist 1 and 68 by radiologist 2. Agreement was deemed substantial in all cases. Pathologists failed to report gas in cavities while radiologists underreported superficial injuries.

CONCLUSION

An overall observation was that less accurate findings were produced by the blinded radiologist in comparison to the non-blinded one. The extremeness of homicides obscured the interpretation of PMCT leading to the observed discrepancies. The combination of PMCT and autopsies is deemed optimal when investigating homicidal events.

A toolbox for the rapid prototyping of crime scene reconstructions in virtual reality

Virtual reality is recently finding its way in forensic work. The required 3D data is nowadays a standard dataset available in many cases, from homicide to traffic collisions, including not only data from the scene but also of weaponry and involved persons. Current investigations use these 3D data to replicated the incident and as discussion base for forensic personal. However, modifying the scene on a 2D viewport is often cumbersome due to the loss of the third dimension. Also to perform the modifications on the scene a 3D operator is often required. Virtual reality might improve this step by its easy use and by visualising the third dimension. This publication presents a variety of tools which can be used in forensic investigations. Additionally to the tools, examples of forensic use of these tools will be presented, showing that already a small number of tools support a variety of forensic applications.

Autopsy diagnosis of acupuncture-induced bilateral tension pneumothorax using whole-body postmortem computed tomography: A case report

RATIONALE

Acupuncture, a component of traditional Chinese medicine, is also a well-known form of complementary and alternative medicine. Serious adverse events of acupuncture have been reported, including the acupuncture-related pneumothorax which is a rare but fatal condition sometimes. The pneumothorax was related to needle insertion in the upper back or paraspinal area and the reported victims suffered from either unilateral or bilateral pneumothorax. Postmortem computed tomography has advantages in the detection of pathologic gas and is being considered as a useful visualization tool for diagnosing the cause of death.

PATIENT CONCERNS

A 52-year-old man underwent acupuncture and cupping treatment at an illegal Chinese medicine clinic for neck and back discomfort and was admitted to the hospital with severe gasp and dyspnea about 30 hours later. The patient suddenly became unconscious with heart rate and blood pressure lost and died after cardiopulmonary resuscitation. Diagnosis, interventions and outcomes: Whole-body postmortem computed tomography of the victim revealed collapse of the both lungs and mediastinal compression, which was also confirmed by autopsy. More than 20 pinprick injuries were found on the skin of the upper and lower back in which multiple pinpricks were located on the body surface projection of the lungs. The cause of death was concluded as acute respiratory and circulatory failure due to acupuncture-induced bilateral tension pneumothorax.

LESSONS

Acupuncture-induced tension pneumothorax is rare and should be recognized by forensic pathologists. Postmortem computed tomography can be used to detect and accurately evaluate the severity of pneumothorax before autopsy and can play a supporting role in determining the cause of death.

Virtual Autopsy as a Screening Test Before Traditional Autopsy: The Verona Experience on 25 Cases

Background:

Interest has grown into the use of multidetector computed tomography (CT) and magnetic resonance imaging as an adjunct or alternative to the invasive autopsy. We sought to investigate these possibilities in postmortem CT scan using an innovative virtual autopsy approach.

Methods:

Twenty-five postmortem cases were scanned with the Philips Brilliance CT-64 and then underwent traditional autopsy. The images were interpreted by two blinded forensic pathologists assisted by a radiologist with the INFOPSY^® Digital Autopsy Software System which provides three-dimensional images in Digital Imaging and Communications in Medicine format. Diagnostic validity of virtual autopsy (accuracy rate, sensitivity, specificity, and predictive values) and concordance between the two forensic pathologists (kappa intraobserver coefficients) were determined.

Results:

The causes of death at traditional autopsies were hemorrhage due to traumatic injuries (n = 8), respiratory failure (5), asphyxia due to drowning (4), asphyxia due to hanging or strangulation (2), heart failure (2), nontraumatic hemorrhage (1), and severe burns (1). In two cases, the cause of death could not be ascertained. In 15/23 (65%) cases, the cause of death diagnosed after virtual autopsy matched the diagnosis reported after traditional autopsy. In 8/23 cases (35%), traditional autopsy was necessary to establish the cause of death. Digital data provided relevant information for inferring both cause and manner of death in nine traumatic cases. The validity of virtual autopsy as a diagnostic tool was higher for traumatic deaths than other causes of death (accuracy 84%, sensitivity 82%, and specificity 86%). The concordance between the two forensic pathologists was almost perfect (>0.80).

Conclusions:

Our experience supports the use of virtual autopsy in postmortem investigations as an alternative diagnostic practice and does suggest a potential role as a screening test among traumatic deaths.

A systematic review on ricochet gunshot injuries

Ricocheted bullets may still retain sufficient kinetic energy to cause gunshot injuries. Accordingly, this paper reviews the literature surrounding gunshot injuries caused by ricocheted bullets. In doing so, it discusses the characteristics of ricochet entrance wounds and wound tracks, noting several important considerations for assessment of a possible ricochet incident. The shapes of ricochet entrance wounds vary, ranging from round holes to elliptical, large and irregular shapes. Pseudo-stippling or pseudo-gunpowder tattooing, pseudo-soot blackening and tumbling abrasions seen on the skin surrounding the bullet hole are particularly associated with ricochet incidents. Ricocheted bullets have a reduced capability for tissue penetration. Most of the resulting wound tracks are short, of large diameter and irregular-all artefacts of the instability of a bullet that has ricocheted. A ricocheted hollow-point bullet, in particular, may overpenetrate the tissue when the bullet nose is deformed or fails to enter the body in a nose-forward orientation. Similarly, internal ricochet may occur when a bullet strikes hard tissue. Postmortem computed tomographic imaging is useful for localising a bullet and its fragments in the body and characterising the wound track. Ricochet cannot be ruled out in normal-appearing entrance wounds unless that finding is supported by other evidence, including the geometrical constraints of the shooting scene and the absence of ricochet marks and a ricocheted bullet.

Postmortem-computed tomography and postmortem-computed tomography-angiography: a focused update

The use of multidetector CT (MDCT) represents a reality routinely used in several forensic institutes, for the numerous advantages that this diagnostic tool can provide; costs are becoming increasingly lower; data acquisition is always faster and once acquired may be revalued at any time. However, there are also some diagnostic limitations, for example, the visualization of the vascular system or a limited soft tissue contrast. In order to overcome these limitations, in recent years, contrast medium has been introduced in postmortem cases, with the development of several techniques of PMCT angiography (PMCTA) and standardized protocols to make them easily reproducible. The aim of this review is to highlight the advantages and pitfalls of PMCT and PMCTA in forensic investigation, taking into consideration the broad spectrum of applications both for natural and unnatural deaths and the numerous methods currently used. Secondly, in the light of the considerable progress in this field and the attempt to develop standardized protocols of PMCTA, the authors aim to evaluate the diagnostic value of PMCTA in comparison both to PMCT and conventional autopsy.

Imaging for homicide investigations

The authors present the opportunities of the application of post-mortem imaging, focusing on post-mortem computed tomography and post-mortem computed tomography angiography in modern forensic investigation of homicide cases. The paper is based on scientific publications related to the subject from ca. the past 10 years, supplemented by the authors' own experiences. The article is illustrated with reconstructions based on the authors' own cases related to homicide due to ballistic/sharp/blunt trauma. As is shown, the results of evaluation of post-mortem computed tomography allow better diagnosis, documentation and visualisation of forensic examinations.

Three rounds as "tandem bullets": unusual findings in a case of a suicidal gunshot to the head

We report an unusual case of suicide in which three 7.65 caliber projectiles were found in the single gunshot wound to the head of a 53-year-old man. Based on data collected at the death scene, CT scan, autopsy findings, and ballistics analysis, the events were reconstructed as follows: two 7.65 mm rounds had already been fired from the 9 mm Makarov pistol the subject was using but, being a smaller caliber, the cartridges had slipped forward and lodged within the barrel. When a third 7.65 mm cartridge was chambered and the gun fired for the third time, the nose of the last bullet hit the lodged bullets and all three rounds were propelled out of the muzzle in tandem as a single shot. Ballistic investigations confirmed that the kinetic energy of the three tandem bullets would have been sufficient to perforate the skull. In cases of gunshot wounds where the manner of death is unclear, a number of well-described circumstantial parameters, such as an atypical anatomical location of the gunshot, unusual firearm, or ammunition, as well as ambiguous autopsy findings, can raise doubts about the manner of death. In very rare cases, despite a single entrance wound, two or more bullets are recovered from the body, fired by the same weapon at the same time (the so-called "tandem bullet" phenomenon). Injuries by "tandem bullets" have crucial implications in gunshot deaths because of the mismatch between the number of entrance and exit wounds and the number of bullets found in or near the body.

Criminal gunshot wound and iatrogenic tension pneumothorax detected by post-mortem computed tomography

Post-mortem imaging at autopsy is gradually increasing in popularity among forensic practitioners. The objective of the present paper was to demonstrate that it is essential to survey the cadaver using computed tomography (CT) before autopsy. This case report presents an iatrogenic tension pneumothorax caused by left subclavian vein puncture undertaken during treatment for a gunshot-related wound. The victim, a 64-year-old woman, was shot by her husband at home, and transferred to the hospital emergency unit. Before surgical procedures were carried out, left subclavian vein puncture was performed; however, during the operation, the victim experienced sudden cardiac arrest. Subsequent intensive resuscitation was unsuccessful. The clinical cause of death was recorded as traumatic shock caused by the gunshot injury. However, before the legal autopsy took place, CT clarified the existence of tension pneumothorax not on the same side as the gunshot wound, but on the side of the iatrogenic subclavian vein puncture. Because of this information gained prior to legal dissection, a typical dissection procedure for tension pneumothorax could be performed. Post-mortem imaging prior to regular dissection is essential as an adjunct diagnostic tool.