Virtual autopsy using imaging: bridging radiologic and forensic sciences. A review of the Virtopsy and similar projects

Primary blast lung injury prevalence and fatal injuries from explosions: insights from postmortem computed tomographic analysis of 121 improvised explosive device fatalities

BACKGROUND

Primary blast lung injury (PBLI) is an acknowledged cause of death in explosive blast casualties. In contrast to vehicle occupants following an in-vehicle explosion, the injury profile, including PBLI incidence, for mounted personnel following an external explosion has yet to be as well defined.

METHODS

This retrospective study identified 146 cases of UK military personnel killed by improvised explosive devices (IEDs) between November 2007 and July 2010. With the permission of Her Majesty's Coroners, relevant postmortem computed tomography imaging was analyzed. PBLI was diagnosed by postmortem computed tomography. Injury, demographic, and relevant incident data were collected via the UK Joint Theatre Trauma Registry.

RESULTS

Autopsy results were not available for 1 of 146 cases. Of the remaining 145 IED fatalities, 24 had catastrophic injuries (disruptions), making further study impossible, leaving 121 cases; 79 were dismounted (DM), and 42 were mounted (M). PBLI was noted in 58 cases, 33 (79%) of 42 M fatalities and 25 (32%) of 79 DM fatalities (p < 0.0001). Rates of associated thoracic trauma were also significantly greater in the M group (p < 0.006 for all). Fatal head (53% vs. 23%) and thoracic trauma (23% vs. 8%) were both more common in the M group, while fatal lower extremity trauma (7% vs. 48%) was more commonly seen in DM casualties (p < 0.0001 for all).

CONCLUSION

Following IED strikes, mounted fatalities are primarily caused by head and chest injuries. Lower extremity trauma is the leading cause of death in dismounted fatalities. Mounted fatalities have a high incidence of PBLI, suggesting significant exposure to primary blast. This has not been reported previously. Further work is required to determine the incidence and clinical significance of this severe lung injury in explosive blast survivors. In addition, specific characteristics of the vehicles should be considered.

Photogrammetric documentation of regions of interest at autopsy--a pilot study

In this pilot study, the authors tested whether photogrammetry can replace or supplement physical measurements made during autopsies and, based on such measurements, whether virtual computer models may be applicable in forensic reconstructions. Photogrammetric and physical measurements of markers denoting wounds on five volunteers were compared. Virtual models of the volunteers were made, and the precision of the markers' locations on the models was tested. Twelve of 13 mean differences between photogrammetric and physical measurements were below 1 cm, which indicates that the photogrammetric method has a high accuracy. The precision of the markers' location on the models was somewhat less, although the method is still promising and potentially superior to the current procedures used for reconstructions. The possibility to measure any distance on a body, even after the autopsy is concluded and the corpse is no longer available, is one of the biggest benefits of photogrammetry.

Postmortem ventilation in cases of penetrating gunshot and stab wounds to the chest

We sought to determine the effect of postmortem ventilation in combination with a suction pump in cases showing penetrating trauma to the chest with haemo- and/or pneumothorax, for better evaluation of the lungs in postmortem computed tomography (PMCT). The study included 6 subjects (1 female, 5 male; age 32-67years) with a penetrating gunshot or stab wound to the chest and consecutive pneumo- and/or haemothorax. The pneumo- and haemothorax were evacuated by a suction pump, and postmortem ventilation was applied using a home care ventilator. PMCT images with and without postmortem ventilation were compared, as well as the autopsy results. In three cases haemo- and pneumothorax was clearly reduced. Postmortem ventilation led to distinct re-expansion of the lungs in two cases, and to re-expansion of single lung lobes in two cases with shotgun injuries. No visible effect was seen in the remaining two cases, because of extensive destruction of lung tissue and blood aspiration. In two cases the injuries sustained in the individual lung lobes were successfully located during postmortem ventilation. The bullet channel was apparent in one case; in another case, injury of the pericardium became visible by generating pneumopericardium. The present method is capable of improving evaluation of the postmortem lung in the presence of single stab or gunshot wounds and if there is no severe destruction of the respiratory system and aspiration. Forensic autopsy should still be considered as the gold standard, although in some cases the present method might be helpful, especially where no autopsy is required.

Identifying future 'unexpected' survivors: a retrospective cohort study of fatal injury patterns in victims of improvised explosive devices

OBJECTIVES

To identify potentially fatal injury patterns in explosive blast fatalities in order to focus research and mitigation strategies, to further improve survival rates from blast trauma.

DESIGN

Retrospective cohort study.

PARTICIPANTS

UK military personnel killed by improvised explosive device (IED) blasts in Afghanistan, November 2007-August 2010.

SETTING

UK military deployment, through NATO, in support of the International Security Assistance Force (ISAF) mission in Afghanistan.

DATA SOURCES

UK military postmortem CT records, UK Joint Theatre Trauma Registry and associated incident data.

MAIN OUTCOME MEASURES

Potentially fatal injuries attributable to IEDs.

RESULTS

We identified 121 cases, 42 mounted (in-vehicle) and 79 dismounted (on foot), at a point of wounding. There were 354 potentially fatal injuries in total. Leading causes of death were traumatic brain injury (50%, 62/124 fatal injuries), followed by intracavity haemorrhage (20.2%, 25/124) in the mounted group, and extremity haemorrhage (42.6%, 98/230 fatal injuries), junctional haemorrhage (22.2%, 51/230 fatal injuries) and traumatic brain injury (18.7%, 43/230 fatal injuries) in the dismounted group.

CONCLUSIONS

Head trauma severity in both mounted and dismounted IED fatalities indicated prevention and mitigation as the most effective strategies to decrease resultant mortality. Two-thirds of dismounted fatalities had haemorrhage implicated as a cause of death that may have been anatomically amenable to prehospital intervention. One-fifth of the mounted fatalities had haemorrhagic trauma which currently could only be addressed surgically. Maintaining the drive to improve all haemostatic techniques for blast casualties, from point of wounding to definitive surgical proximal vascular control, alongside the development and application of novel haemostatic interventions could yield a significant survival benefit. Prospective studies in this field are indicated.

Diagnosis of drowning using post-mortem computed tomography based on the volume and density of fluid accumulation in the maxillary and sphenoid sinuses

Recent studies have reported that drowning victims frequently have fluid accumulation in the paranasal sinuses, most notably the maxillary and sphenoid sinuses. However, in our previous study, many non-drowning victims also had fluid accumulation in the sinuses. Therefore, we evaluated the qualitative difference in fluid accumulation between drowning and non-drowning cases in the present study. Thirty-eight drowning and 73 non-drowning cases were investigated retrospectively. The fluid volume and density of each case were calculated using a DICOM workstation. The drowning cases were compared with the non-drowning cases using the Mann-Whitney U-test because the data showed non-normal distribution. The median fluid volume was 1.82 (range 0.02-11.7) ml in the drowning cases and 0.49 (0.03-8.7) ml in the non-drowning cases, and the median fluid density was 22 (-14 to 66) and 39 (-65 to 77) HU, respectively. Both volume and density differed significantly between the drowning and non-drowning cases (p=0.001, p=0.0007). Regarding cut-off levels in the ROC analysis, the points on the ROC curve closest (0, 1) were 1.03ml (sensitivity 68%, specificity 68%, PPV 53%, NPV 81%) and 27.5 HU (61%, 70%, 51%, 77%). The Youden indices were 1.03ml and 37.8 HU (84%, 51%, 47%, 86%). When the cut-off level was set at 1.03ml and 27.5HU, the sensitivity was 42%, specificity 45%, PPV 29% and NPV 60%. When the cut-off level was set at 1.03ml and 37.8HU, sensitivity was 58%, specificity 32%, PPV 31% and NPV 59%.

Incidence of delayed and missed diagnoses in whole-body multidetector CT in patients with multiple injuries after trauma

BACKGROUND

Whole-body CT (WBCT) is the imaging modality of choice during the initial diagnostic work-up of multiple injured patients in order to identify serious injuries and initiate adequate treatment immediately. However, delayed diagnosed or even missed injuries have been reported frequently ranging from 1.3% to 47%.

PURPOSE

To highlight commonly missed lesions in WBCT of patients with multiple injuries.

MATERIAL AND METHODS

A total of 375 patients (age 42.8 ± 17.9 years, ISS 26.6 ± 17.0) with a WBCT (head to symphysis) were included. The final CT report was compared with clinical and operation reports. Discrepant findings were recorded and grouped as relevant and non-relevant to further treatment. In both groups, an experienced trauma radiologist read the CT images retrospectively, whether these lesions were missed or truly not detectable.

RESULTS

In 336 patients (89.6%), all injuries in the regions examined were diagnosed correctly in the final reports of the initial CT. Forty-eight patients (12.8%) had injuries in regions of the body that were not included in the CT. Fourteen patients (3.7%) had injuries that did not require further treatment. Twenty-five patients (6.7%) had injuries that required further treatment. With secondary interpretation, 85.4% of all missed lesions could be diagnosed in retrospect from the primary CT data-set. Small pancreatic and bowel contusions were identified as truly non-detectable.

CONCLUSION

In multiple traumas, only a few missed injuries in initial WBCT reading are clinically relevant. However, as the vast majority of these injuries are detectable, the radiologist has to be alert for commonly missed findings to avoid a delayed diagnosis.

Cross-sectional anatomy, computed tomography and magnetic resonance imaging of the thoracic region of common dolphin (Delphinus delphis) and striped dolphin (Stenella coeruleoalba)

The aim of this study was to provide a detailed anatomical description of the thoracic region features in normal common (Delphinus delphis) and striped dolphins (Stenella coeruleoalba) and to compare anatomical cross-sections with computed tomography (CT) and magnetic resonance imaging (MRI) scans. CT and MRI were used to scan 7 very fresh by-caught dolphin cadavers: four common and three striped dolphins. Diagnostic images were obtained from dolphins in ventral recumbency, and after the examinations, six dolphins were frozen (-20°C) and sliced in the same position. As well as CT and MRI scans, cross-sections were obtained in the three body planes: transverse (slices of 1 cm thickness), sagittal (5 cm thickness) and dorsal (5 cm thickness). Relevant anatomical features of the thoracic region were identified and labelled on each section, obtaining a complete bi-dimensional atlas. Furthermore, we compared CT and MRI scans with anatomical cross-sections, and results provided a complete reference guide for the interpretation of imaging studies of common and striped dolphin's thoracic structures.

Postmortem whole-body MRI in traumatic causes of death

OBJECTIVE

The aim of this study was to determine the sensitivity and specificity of postmortem whole-body MRI for typical injuries resulting from traumatic causes of death.

MATERIALS AND METHODS

Forty cases of accidental death were evaluated with postmortem whole-body MRI. Imaging was conducted according to a standard protocol, and each examination had an average duration of 90 minutes. The imaging findings were correlated with the autopsy findings, which served as the reference standard.

RESULTS

MRI showed the main pathologic process leading to death in 39 of the 40 cases. The sensitivity of postmortem MRI ranged from 100% (pneumothorax) to 40% (fractures of the upper extremities). In general, MRI had a high level of performance for depicting soft-tissue lesions, such as subcutaneous hematoma (e.g., galeal hematoma with a sensitivity 95%). The sensitivity of MRI was remarkably lower for lesions of the upper abdominal organs (liver, 80%; spleen, 50%; pancreas, 60%; kidneys, 66%).

CONCLUSION

Postmortem whole-body MRI had overall good performance for depicting traumatic findings in corpses and therefore may serve an important role as an adjunct to classic autopsy for the forensic examination of cases of traumatic cause of death. However, the reduced sensitivity of postmortem MRI for lacerations of the upper abdominal organs and the observed superimposition of antemortem findings and postmortem findings (e.g., in the pulmonary tissue) in this retrospective study suggest that whole-body postmortem MRI not be recommended as a replacement for classic autopsy.

Virtual autopsy using multislice computed tomography in forensic medical diagnosis of drowning

PURPOSE

This study evaluated the usefulness of multidetector computed tomography (MDCT) in the postmortem diagnosis of death by drowning in fresh water by measuring the difference of blood density within the cardiac chambers.

MATERIALS AND METHODS

Twenty-two corpses including six cases of fresh-water drowning (group A) and 16 deaths by other causes (group B), among which were also different forms of mechanical asphyxia other than drowning, underwent MDCT and conventional autopsy. Blood density within the right and left heart chambers, the aorta and the pulmonary trunk was measured and values compared between groups and within each group between heart chambers.

RESULTS

Blood density in all cardiac chambers was lower in group A than in group B. The difference was statistically significant within the left atrium and ventricle and was significantly lower in the left than in the right heart chambers in group A only.

CONCLUSIONS

MDCT, together with conventional autopsy, may contribute to the diagnosis of drowning, by measuring blood density in the heart chambers.

Whole-body post-mortem computed tomography compared with autopsy in the investigation of unexpected death in infants and children

OBJECTIVES

To investigate the contribution of whole-body post-mortem computed tomography (PMCT) in sudden unexpected death in infants and children.

METHODS

Forty-seven cases of sudden unexpected death in children investigated with radiographic skeletal survey, whole-body PMCT and autopsy were enrolled. For imaging interpretation, non-specific post-mortem modifications and abnormal findings related to the presumed cause of death were considered separately. All findings were correlated with autopsy findings.

RESULTS

There were 31 boys and 16 girls. Of these, 44 children (93.6 %) were younger than 2 years. The cause of death was found at autopsy in 18 cases (38.3 %), with 4 confirmed as child abuse, 12 as infectious diseases, 1 as metabolic disease and 1 as bowel volvulus. PMCT results were in accordance with autopsy in all but three of these 18 cases. Death remains unexplained in 29 cases (61.7 %) and was correlated with no abnormal findings on PMCT in 27 cases. Major discrepancies between PMCT and autopsy findings concerned pulmonary analysis.

CONCLUSIONS

Whole-body PMCT may detect relevant findings that can help to explain sudden unexpected death and is essential for detecting non-accidental injuries. We found broad concordance between autopsy and PMCT, except in a few cases of pneumonia. It is a non-invasive technique acceptable to relatives.

KEY POINTS

• Whole-body post-mortem computed tomography (PMCT) is an effective non-invasive method. • Whole-body PMCT is essential for detecting child abuse in unexpected death. • There is concordance on cause of death between PMCT and autopsy. • Whole-body PMCT could improve autopsy through dissection and sampling guidance. • PMCT shows findings that may be relevant when parents reject autopsy.

Virtopsy in a red kangaroo with oral osteomyelitis

This report describes the use of computed tomography (CT) in a nondomestic species. Postmortem CT was performed on a red kangaroo (Macropus rufus) and a diagnosis of oral osteomyelitis was made. CT examination revealed bony remodeling of the right mandible, an intraosseous lesion of the right temporal bone, muscle necrosis around the right mandible, and the absence of the right, first, upper molar tooth. Cardiac and intrahepatic gas and a distended intestine due to postmortem gas accumulation were also seen. All the lesions identified with CT were also identified by conventional necropsy, except the cardiac and intrahepatic gases. Virtopsy may be a useful procedure for the noninvasive identification of cause of death and as a guide for necropsy in animals.

Detection of coronary thrombosis after multi-phase postmortem CT-angiography

The aim of this study was to compare postmortem angiography-based, autopsy-based and histology-based diagnoses of acute coronary thrombosis in a series of medicolegal cases that underwent postmortem angiographies according to multiphase CT-angiography protocol. Our study included 150 medicolegal cases. All cases underwent native CT-scan, postmortem angiography, complete conventional autopsy and histological examination of the main organs and coronary arteries. In 10 out of the 150 investigated cases, postmortem angiographies revealed coronary arterial luminal filling defects and the absence of collateral vessels, suggesting acute coronary thromboses. Radiological findings were confirmed by autopsy and histological examinations in all cases. In 40 out of 150 cases, angiograms revealed complete or incomplete coronary arterial luminal filling defects and the presence of collateral vessels. Histological examinations did not reveal free-floating or non-adherent thrombi in the coronary arteries in any of these cases. Though postmortem angiography examination has not been well-established for the diagnosis of acute coronary thrombosis, luminal filling defects in coronary arteries suggesting acute thromboses can be observed through angiography and subsequently confirmed by autopsy and histological examinations.

Assessment of the relationship between drowning and fluid accumulation in the paranasal sinuses on post-mortem computed tomography

Recent reports have detailed common computed tomography (CT) findings in drowning victims, most notably fluid accumulation in the maxillary and sphenoidal sinuses. This CT finding could help forensic doctors to diagnose drowning. This study retrospectively investigated 151 subjects: 39 drowning and 112 non-drowning cases. Pearson's chi-square tests demonstrated that fluid accumulation in the maxillary or sphenoidal sinuses was associated significantly with drowning (p=0.0001). The sensitivity of the drowning diagnosis was 97%, specificity was 35%, accuracy was 51%, positive predictive value was 34% and negative predictive value was 98%. Drowning was significantly associated with fluid accumulation in the maxillary and sphenoidal sinuses, but the specificity and positive predictive value of the drowning diagnosis were poor. Although the presence of fluid in the maxillary and sphenoidal sinuses cannot be used to diagnose drowning, the absence of the fluid can be used to virtually exclude drowning.

Arterial air emboli on computed tomography (CT) autopsy

OBJECTIVE

To describe radiological appearances of systemic air emboli versus intravascular air from putrefaction.

MATERIALS AND METHODS

The hospital trauma database was searched for patients who underwent computed tomography (CT) autopsy. The studies were reviewed and evaluated for intravascular gas. The appearances and location of intravascular air were characterised.

RESULTS

Four cases of intravascular gas were identified out of 15 cases of CT autopsy performed from March 2004 to December 2006. In three cases, intravascular air was predominantly in the arterial system, coupled with severe pulmonary injury. In one case, the air was predominantly in the venous system with a large amount of gas in portal veins.

CONCLUSION

We propose to consider pulmonary alveoli-venous fistula as a possible cause of systemic air emboli, as identified on CT autopsy by large amounts of gas in the arterial circulation, coupled with severe pulmonary injury.

Forensic odontology in the disaster victim identification process

Disaster victim identification (DVI) is an intensive and demanding task involving specialists from various disciplines. The forensic dentist is one of the key persons who plays an important role in the DVI human identification process. In recent years, many disaster incidents have occurred that challenged the DVI team with various kinds of difficulties related to disaster management and unique situations in each disaster. New technologies have been developed to make the working process faster and more effective and the different DVI protocols have been evaluated and improved. The aim of this article is to collate all information regarding diagnostic tools and methodologies pertaining to forensic odontological DVI, both current and future. It can be concluded that lessons learned from previous disaster incidents have helped to optimize working protocols and to develop new tools that can be applied in future DVI operation. The working procedures have been greatly improved by newly developed technologies.

Weapon identification using antemortem computed tomography with virtual 3D and rapid prototype modeling--a report in a case of blunt force head injury

A frequent request of a prosecutor referring to forensic autopsy is to determine the mechanism of an injury and to identify the weapons used to cause those injuries. This task could be problematic in many ways, including changes in the primary injury caused by medical intervention and the process of healing. To accomplish this task, the forensic pathologist has to gather all possible information during the post-mortem examination. The more data is collected, the easier it is to obtain an accurate answer to the prosecutor's question. The authors present a case of head injuries that the victim sustained under unknown circumstances. The patient underwent neurosurgical treatment which resulted in alteration of the bone fracture pattern. The only way to evaluate this injury was to analyze antemortem clinical data, especially CT scans, with virtual 3D reconstruction of the fractured skull. A physical model of a part of the broken skull was created with the use of 3D printing. These advanced techniques, applied for the first time in Poland for forensic purposes, allowed investigators to extract enough data to develop a hypothesis about the mechanism of injury and the weapon most likely used.

Gas at postmortem computed tomography--an evaluation of 73 non-putrefied trauma and non-trauma cases

Postmortem computed tomography (PMCT) has become an important complement in investigating forensic cases allowing an accurate detection of gas accumulations. The present study investigated the presence and distribution of gas in a large number of non-putrefied cases of traumatic and non-traumatic deaths. Furthermore the possibility of pneumobilia secondary to blunt abdominal trauma was studied. Retrospectively, 73 cases, underwent a whole-body PMCT prior to autopsy. These were divided into four groups: penetrating trauma (20 gunshot cases, 13 stabbing cases), blunt abdominal trauma (20 cases) and a control group of 20 non-trauma cases. Exclusion criteria were visible signs of decomposition. Each group was screened for gas accumulations in the vascular system, internal organs, soft tissues and body cavities. Gas accumulations were present in 98% of the trauma cases, compared to 80% of the control group. The most affected structures and/or organs in the trauma group were soft tissues, vessels and the liver. In most cases of the trauma group gas was associated with open injuries and lacerations of vessels. Furthermore, in the gunshot group gas was frequently seen in the intracranial cavity. Pneumobilia occurred in one case of the blunt trauma group; in that control group gas was also seen, but less frequently. Gas accumulation showed a strong association with traumatic events, but even the majority of non-trauma cases showed gas accumulations. Despite the exclusion of cases with visible decomposition signs, a putrefactive origin of gas was assumed in some cases. Gas accumulations are a frequent finding in PMCT with a higher incidence in (open) trauma cases. Even though a differentiation between putrefactive and traumatic gas accumulations is still difficult, knowledge of the circumstance surrounding the case may help identify the origin of gas.

The forensic radiographer: a new member in the medicolegal team

Multidetector computed tomography is becoming more widespread in forensic medicine. In most services, autopsy assistants perform the radiological examination. We introduced professional radiographers into the legal medicine service and hypothesized they would also be able to take over duties currently reserved for other specialists. The aims of this study were to evaluate if radiographers could be trained as "forensic radiographers" by (1) integrating graduated medical radiographers into the legal medicine service, (2) investigating the advantages of this collaboration, and (3) defining the duties of the forensic radiographers.The study was performed prospectively on a group of 8 recruited radiographers who underwent a testing period with special training. They learned the basics of medicolegal case treatment, the autonomous execution of postmortem computed tomography angiography, and postprocessing of data. Seven of 8 radiographers finished the training and were integrated into our service. Although all radiographers were able to fulfill the duties demanded after the training period, some radiographers could not enter or complete the program because they were unable to work with dead bodies.Our study presents the advantages of integrating radiographers into the medicolegal team and proposes how to train the forensic radiographers. In addition, the duties and responsibilities of these new specialists are defined.

[Virtual autopsy (virtopsy) in forensic science: from the scalpel to the scanner]

The aim of "virtopsy" is to utilize modern imaging technology to optimize classical autopsy documentation. The benefits of virtopsy include examiner-independent, objective 3D documentation and its non-invasive approach. Virtopsy is an option in cases where autopsy is rejected by family members or for religious reasons. It is also suitable as a rapid identification and examination tool in large-scale disasters. Forensic findings can be presented to prosecutors and courts in 3D and without bloody images.

Postmortem computed tomography images of a broken piece of a weapon in the skull

The use of post-mortem radiological imaging is becoming increasing widespread in forensic medicine. These images can help improve the quality and safety of autopsy. We report two cases of homicide victims that had broken pieces of a weapon in their skull. Postmortem multislice computed tomography (MSCT) demonstrated metal artifacts in the skull of two homicide cases. Autopsy showed that both artifacts were pieces broken off of a sharp instrument. Some possible benefits of postmortem MSCT include the ability to reconstruct visual images of weapons and the possible prevention of injury to autopsy personnel.

Reconstruction and 3D visualisation based on objective real 3D based documentation

Reconstructions based directly upon forensic evidence alone are called primary information. Historically this consists of documentation of findings by verbal protocols, photographs and other visual means. Currently modern imaging techniques such as 3D surface scanning and radiological methods (computer tomography, magnetic resonance imaging) are also applied. Secondary interpretation is based on facts and the examiner's experience. Usually such reconstructive expertises are given in written form, and are often enhanced by sketches. However, narrative interpretations can, especially in complex courses of action, be difficult to present and can be misunderstood. In this report we demonstrate the use of graphic reconstruction of secondary interpretation with supporting pictorial evidence, applying digital visualisation (using 'Poser') or scientific animation (using '3D Studio Max', 'Maya') and present methods of clearly distinguishing between factual documentation and examiners' interpretation based on three cases. The first case involved a pedestrian who was initially struck by a car on a motorway and was then run over by a second car. The second case involved a suicidal gunshot to the head with a rifle, in which the trigger was pushed with a rod. The third case dealt with a collision between two motorcycles. Pictorial reconstruction of the secondary interpretation of these cases has several advantages. The images enable an immediate overview, give rise to enhanced clarity, and compel the examiner to look at all details if he or she is to create a complete image.

The effectiveness of postmortem multidetector computed tomography in the detection of fatal findings related to cause of non-traumatic death in the emergency department

OBJECTIVES

To investigate the diagnostic performance of postmortem multidetector computed tomography (PMMDCT) for the detection of fatal findings related to causes of non-traumatic death in the emergency department (ED).

METHODS

494 consecutive cases of clinically diagnosed non-traumatic death in ED involving PMMDCT were enrolled. The fatal findings were detected on PMMDCT and classified as definite or possible findings. These findings were confirmed by autopsy in 20 cases.

RESULTS

The fatal findings were detected in 188 subjects (38.1%) including 122 with definite (24.7%) and 66 with possible finding (13.4%). Definite findings included 21 cases of intracranial vascular lesions, 84 with intra-thoracic haemorrhage, 13 with retroperitoneal haemorrhage and one with oesophagogastric haemorrhage. In three patients who had initially been diagnosed with non-traumatic death, PMMDCT revealed fatal traumatic findings. Two definite findings (two haemopericardiums) and seven possible findings (two intestinal obstructions, one each of multiple liver tumours central pulmonary artery dilatation, pulmonary congestion, peritoneal haematoma, and brain oedema) were confirmed by autopsy. The causes of death were not determined in cases with possible findings without autopsy.

CONCLUSIONS

PMMDCT is a feasible tool for detecting morphological fatal findings in non-traumatic death in ED. It is important to know the ability and limitation of PMMDCT.

Targeted cardiac post-mortem computed tomography angiography: a pictorial review

With the introduction of targeted coronary artery angiography to post-mortem computed tomography (PMCT) it is now possible to assess the coronary arteries and left ventricle after death without, case dependent, the necessity to undertake an invasive autopsy. The purpose of this pictorial review is to act as a walk through aid memoire and educational learning document for radiologists and pathologists alike who may be new to the use and interpretation of targeted PMCT angiography. By using an example scanning protocol, which uses both positive and negative (air) contrast mediums, this pictorial review provides a systematic approach to vessel and ventricular assessment that is based upon clinical cardiac angiography but adapted to PMCT.

Postmortem X-ray Computed Tomography (CT) and Forensic Autopsy: A Review of the Utility, the Challenges and the Future implications

The utility of computed tomography (CT) for forensic autopsy is being defined. Small studies have indicated potential areas of use. Systematic studies are few. Evidence of the utility of CT as an autopsy substitute in fatal trauma cases has been inconsistent. Some studies show that there are injuries seen by CT that aren't detected by autopsy indicating that CT, at least, is likely useful as an autopsy adjunct. Research has been limited by small study populations, variation in postmortem interval, differences in protocols including CT slice thickness, who interpreted the scans (radiologists vs. pathologists), and how injuries were scored. Challenges exist to implement and use advanced imaging technology for the forensic autopsy. It is important to determine how to arrange these technologies into a coherent approach to postmortem diagnosis while not encumbering forensic pathologists. Forensic pathologists and radiologists require training in interpreting the unique aspects of postmortem CT scans. Some forensic pathologists might perceive imaging technology as a threat and express concern that it will make the autopsy obsolete.

If CT is found to supplant or supplement autopsy in valuable ways, more comprehensive diagnostic information can be provided. If CT can supplant the use of autopsy in certain situations and significantly decrease autopsy numbers it will allow offices to achieve an annual cost savings and divert these resources to other needs. If CT becomes widely available and can supplant autopsy, it could make up some of the gap between the numbers of forensic pathologists available and the numbers needed nationally.

Investigation of the role of computed tomography as an adjunct to autopsy in the evaluation of stillbirth

INTRODUCTION

The number of parents agreeing to autopsy following stillbirth is declining, which has undermined clinicians' ability to assess causes of intrauterine death and can impact counselling regarding recurrence. Post-mortem radiological imaging is a potential alternative method of investigating perinatal loss. The aim of this study was to assess the role of multi-detector computed tomography (MDCT) in the investigation of stillbirth.

STUDY DESIGN

Following ethical approval and written consent, parents were offered MDCT of the stillborn infant. MDCT was performed with 3D reconstruction, and images were analysed for image quality, anthropomorphic measurements and pathologic findings. Body part and organ-specific measurements were performed; including head, chest and abdominal circumferences, and muscle and liver mass was also measured. Findings were correlated with obstetric history, post-mortem skeletal survey (plain radiography), and formal autopsy.

RESULTS

Fourteen third-trimester stillborn infants were scanned. Image quality was moderate to excellent for most body structures. CT was better than plain radiography for imaging skeletal structures and large solid organs and demonstrated a range of pathologies including renal vein thrombosis, mesenteric calcification and skeletal hyperostosis that were not seen on plain radiographs. MDCT did not overlook autopsy findings and provided some additional information.

CONCLUSION

This study confirms the feasibility of MDCT in the investigation of third trimester stillbirth. MDCT image quality is acceptable and the examination can demonstrate a range of anatomic and pathologic findings. Initially, its value may be as an important adjunct to conventional autopsy.

Age estimation and the developing third molar tooth: an analysis of an Australian population using computed tomography

The third molar tooth is one of the few anatomical sites available for age estimation of unknown age individuals in the late adolescent years. Computed tomography (CT) images were assessed in an Australian population aged from 15 to 25 years for development trends, particularly concerning age estimation at the child/adult transition point of 18 years. The CT images were also compared to conventional radiographs to assess the developmental scoring agreement between the two and it was found that agreement of Demirjian scores between the two imaging modalities was excellent. The relatively wide age ranges (mean ± 2SD) indicate that the third molar is not a precise tool for age estimation (age ranges of 3-8 years) but is, however, a useful tool for discriminating the adult/child transition age of 18 years. In the current study 100% of females and 96% of males with completed roots were over 18 years of age.

Quantitative analysis of intracranial hypostasis: comparison of early postmortem and antemortem CT findings

OBJECTIVE

The purpose of this study was to quantitatively analyze postmortem hypostasis in the intracranial venous sinus on head CT scans compared with the antemortem CT findings in the same patients with the aim of evaluating sedimentation in the heart and great vessels.

MATERIALS AND METHODS

A total of 50 patients on whom head CT was performed before and after death were enrolled. Attenuation in the dorsal part of the superior sagittal sinus was measured at the level of the basal ganglia on both antemortem and postmortem CT scans. Increased attenuation in the transverse sinus and cerebellar tentorium and sedimentation in the heart and great vessels were evaluated visually.

RESULTS

Attenuation in the dorsal part of the superior sagittal sinus increased significantly (p < 0.0001) between antemortem (42.77 ± 6.23 HU) and postmortem (49.72 ± 10.58 HU) CT in 80% of cases. Increased attenuation of the transverse sinus or cerebellar tentorium was observed in 48% of cases and sedimentation in the heart or great vessels in 62% of cases. Increased attenuation in the superior sagittal sinus was clearly evident in patients with sedimentation in the heart or great vessels (antemortem, 43.81 ± 6.17 HU; postmortem, 54.65 ± 8.51 HU) compared with the patients without evidence of sedimentation (antemortem, 41.06 ± 6.10 HU; postmortem, 41.66 ± 8.57 HU) (p < 0.0001).

CONCLUSION

Intracranial hypostasis is a common postmortem CT finding. Radiologists and physicians who interpret postmortem neurologic images should be aware of intracranial hypostasis and differentiate this phenomenon from intracranial hemorrhage.

The use of computed tomography (CT) to estimate age in the 2009 Victorian Bushfire Victims: a case report

The development of new imaging technologies is beginning to have an impact upon medico-legal death investigation in an increasing number of jurisdictions. Computed tomography (CT) is an imaging modality which is able to provide information to investigators without the need for a physically invasive autopsy in certain circumstances. The use of post-mortem CT as an aid to the identification of the victims of the Black Saturday bushfires is discussed with particular reference to dental age estimation. A case report is presented which demonstrates the ability of this imaging modality to separate individuals based upon dental development. Whilst CT is not yet able to adequately discriminate between differing restoration types and shapes, and therefore cannot be used for dental identification in the classic sense, the ability of this imaging modality to assess dental and skeletal development for the purpose of age estimation is valid.

Utility of postmortem autopsy via whole-body imaging: initial observations comparing MDCT and 3.0 T MRI findings with autopsy findings

Objective

We prospectively compared whole-body multidetector computed tomography (MDCT) and 3.0T magnetic resonance (MR) images with autopsy findings.

Materials and Methods

Five cadavers were subjected to whole-body, 16-channel MDCT and 3.0T MR imaging within two hours before an autopsy. A radiologist classified the MDCT and 3.0T MRI findings into major and minor findings, which were compared with autopsy findings.

Results

Most of the imaging findings, pertaining to head and neck, heart and vascular, chest, abdomen, spine, and musculoskeletal lesions, corresponded to autopsy findings. The causes of death that were determined on the bases of MDCT and 3.0T MRI findings were consistent with the autopsy findings in four of five cases. CT was useful in diagnosing fatal hemorrhage and pneumothorax, as well as determining the shapes and characteristics of the fractures and the direction of external force. MRI was effective in evaluating and tracing the route of a metallic object, soft tissue lesions, chronicity of hemorrhage, and bone bruises.

Conclusion

A postmortem MDCT combined with MRI is a potentially powerful tool, providing noninvasive and objective measurements for forensic investigations.