Advances in post-mortem CT-angiography

Changes in tissues and organs through PMCTA carrier substances

To date, lipophilic contrast agents mixed with oil, usually paraffin oil, are the most commonly used contrast agents in post-mortem computed tomography angiography (PMCTA). Iodine-based hydrophilic contrast media in combination with a water-soluble carrier, e.g. polyethylene glycol (PEG), are also common. However, their influence on different tissues and organs is poorly understood. In order to analyse the changes in the cadavers caused by the different carrier substances, we evaluated the effects of PEG 200 and oil on the different tissues and organs. Therefore, during a forensic autopsy, liquid femoral vein blood and samples of different organs and vessels were taken and preserved at room temperature in the two liquids mentioned. The condition of the samples was documented during the autopsy and 24, 48 and 72 h after preservation. Microscopic examination took place after 72 h. After 24 h, the samples placed in PEG 200 already showed a clear solidification of almost all structures. Crumbly blood agglomerates had formed in the previously liquid blood. In contrast, the samples stored in oil showed signs of classic cadaveric decomposition after 24 h, which increased with time. The microscopic and immunohistochemical evaluation of the samples stored in PEG showed a good diagnostic quality. The analysis of tissues stored in oil was much more difficult due to putrefaction. PEG and oil show significantly different effects on human tissues, mainly conservation and dehydration are affected. It is crucial to be aware of these differences in order to choose the most appropriate PMCTA method for each forensic case.

A single Angiofil-latex injection for both radiological and anatomical assessment of arterial territories in the limbs

INTRODUCTION

Postmortem evaluation of the human vascular system has a long history, with advancements ranging from dissections to modern imaging techniques like computed tomography (CT scan). This study designs a novel combination of Angiofil, a liquid radiopaque polymer, and latex, a flexible cast material, for cadaveric vascular analysis.

MATERIAL & METHODS

The aim was to synergize the advantages of both components, providing accurate radiological images and optimal dissection conditions. Three arterial territories (lateral circumflex femoral artery, profunda brachii artery, and radial artery) were injected and assessed through CT scans and dissections.

RESULTS

The Angiofil-latex mixture allowed successful visualization of the vascular networks, offering a simple, reproducible, and non-toxic approach. Quantitative assessments of the three territories, including diameters and lengths, showed comparable results between CT scan and dissection.

DISCUSSION

The technique precision and versatility make it an accessible and valuable tool for anatomical studies, potentially extending its application to MRI analyses. Overall, the Angiofil-latex combination presents a cost-effective solution for researchers, offering enhanced visibility and detailed anatomical insights for various applications, including anatomical variation studies.

Illustrated cross-sectional computed tomography of the cetacean abdomino-pelvic organs

BACKGROUND

Computed tomography (CT) is a non-invasive diagnostic imaging modality which can be used to study the anatomy and morphology of live or deceased animals in-situ. In cetaceans, existing CT anatomy studies mostly focused on the head and thoracic regions. Using postmortem CT (PMCT) scans of Indo-Pacific finless porpoises (Neophocaena phocaenoides), this study describes the cross-sectional imaging anatomy of the cetacean abdomino-pelvic organs for the first time.

METHODS

PMCT scans of finless porpoises stranded in Hong Kong waters were reviewed, of which two freshly dead cases, one male and one female, were selected for illustration. In addition, a contrast-enhanced PMCT scan was performed on the female subject as a trial for a PMCT-angiography study (PMCTA) in cetaceans. A total of 18 axial PMCT images were acquired at selected vertebral levels in the abdomen and supplemented with a series of corresponding labeled anatomical diagrams.

RESULTS

By applying different image rendering techniques, most osseous and soft tissue structures in the finless porpoise abdomen were successfully depicted and annotated on PMCT, including the male and female reproductive organs in the pelvic region. The application of contrast medium in PMCT created artificial radiodensity differences which improved the ability to visualize and differentiate soft organs and vasculature. The merits and limitations of CT compared to other imaging modalities, as well as the future directions of PMCT in stranding investigation, were discussed.

CONCLUSIONS

The findings from this study significantly enhance the applications of CT in cetaceans by assisting researchers and veterinarians in the interpretation of cetacean abdomino-pelvic CT for morphological and pathological assessment during clinical or postmortem examination.

Selective postmortem arterial angiography of head and neck using digital x-ray or computed tomography: A practical and rapid method to identify vascular injuries

Identification of vascular injuries is crucial for complete postmortem evaluation and understanding of trauma deaths by the Medical Examiner. Some vascular injuries are difficult to evaluate due to challenging anatomic locations, especially in the head and neck. Documenting injuries of the facial and vertebral arteries is challenging and necessitates time-consuming dissections that can create artifacts and disfigurement. In busy medical examiner offices with a significant number of traumatic injuries, finding a creative solution to employ reliable postmortem angiography is desirable. At the Office of the Chief Medical Examiner for the State of Maryland (OCME), we created and effectively implemented a selective angiography procedure using traditional indwelling Foley catheters and water-soluble barium swallow contrast to evaluate arterial injuries using either digital radiography or computed tomography imaging modalities. This technique and imaging interpretation can be performed by a medical examiner or forensic pathology fellow after basic technical training and basic radiology training. This study outlines the technique, methods, and utilization of the procedure and describes the findings of six deaths due to vascular lesions from different injury mechanisms and disease processes and describes the ease of implementation on a broader scale in busy Medical Examiner's offices.

Pediatric forensic postmortem computed tomography: basics to advanced

The approach to postmortem computed tomography (CT) differs significantly from that of diagnostic CT in living patients. Elimination of artifacts such as noise and beam hardening as well as optimization of tissue contrast requires alteration of exposure parameters from protocols designed to limit radiation dose in children. Multiple scans may be performed, and detailed post-processing can be used to enhance subtle findings such as small intracranial extra axial collections and non-displaced fractures. Basics of postmortem CT technique are discussed here as well as advanced techniques in scanning and post-processing.

Exploring Roemheld syndrome: a comprehensive review with proposed diagnostic criteria

Roemheld syndrome (RS) is a condition that triggers cardiac symptoms due to gastrointestinal compression of the heart. It is often misdiagnosed as other types of cardiac or digestive disorders, leading to unnecessary treatments and reduced quality of life. Here, we provide a thorough review of RS, covering its pathogenesis, etiology, diagnosis, treatment, and outcome. We found that a number of conditions, including gallstones, hiatal hernia, excessive gas, and gastroesophageal reflux syndrome, can cause RS. The symptoms of RS can include chest pain, palpitations, shortness of breath, nausea, vomiting, bloating, and abdominal pain. Clinical history, physical examination, electrocardiograms, and improvement in symptoms following gastrointestinal therapy can all be used to identify RS. We also propose a set of criteria, the IKMAIR criteria, to improve the diagnostic approach for this condition. Dietary changes, lifestyle adjustments, pharmaceutical therapies, and surgical procedures can all be used to control RS. Depending on the underlying etiology and the outcome of treatment, RS has a varying prognosis. We conclude that RS is a complicated and understudied disorder that needs more attention from researchers and patients as well as from medical professionals. We recommend the inclusion of RS in the differential diagnosis for individuals with gastrointestinal problems and unexplained cardiac symptoms. Additionally, we advise treating RS holistically by attending to its cardiac and gastrointestinal components.

The effect of post-mortem computed tomography angiography (PMCTA) on biomarkers of coronary artery disease

Coronary atherosclerosis is due to build-up of plaque within the coronary arteries. Post-mortem computed tomography (PMCT) allows non or minimally invasive visualization of abnormalities prior to an autopsy, however PMCT-angiography (PMCTA) greatly enhances relevant findings, especially in viewing the cardiovascular system which is important in the diagnosis of coronary atherosclerosis. Contrast media used in PMCTA however has been reported to cause distortion of tissue which may interfere with post-mortem investigation outcomes. A cross sectional study to investigate the effect of PMCTA on tissue biomarkers in coronary arteries was performed involving cases brought in dead to the Institute and Accident and Emergency Unit. Sixty-three autopsy cases were included in this study, whereby 18 cases underwent PMCT while 45 cases underwent PMCTA. The subjects subsequently had a conventional autopsy where coronary artery sections were collected for standard histological examination and immunohistochemistry examination for endothelial inflammatory (CD36), prothrombogenic (TPA) and plaque stability (MMP-9) markers. The subjects consisted of 55 males and 8 females with a mean age ±SD of 49 ± 18.11 years. There were no significant differences in the coronary artery endothelial expression of CD36, MMP-9 and TPA between PMCT and PMCTA subjects. PMCTA does not alter CD36, TPA and MMP-9 markers supporting the safe use of PMCTA in post-mortem examinations.

The value of PMCTA in the diagnosis of coronary atherosclerosis in isolated human hearts

Postmortem computed tomography (PMCT) has a limited value in investigating coronary artery disease, despite several obvious advantages over the conventional autopsy. To address this issue, postmortem computed tomography angiography (PMCTA) has been introduced into various studies, where it has been used to investigate natural and unnatural deaths involving vascular damage, occlusion, or other pathologies of the vascular system. To investigate the application value of PMCTA in the diagnosis of coronary artery stenosis in ex situ hearts, the water-based contrast media were injected into isolated hearts, scaned, and finally compared with gold standards (autopsy and histology findings of the coronary artery). This study involved 16 subjects from the Academy of Forensic Science who were suspected to have died of sudden death without traumatic injuries. Unenhanced PMCT was performed first, followed by PMCTA using a water-based contrast agent, injected into the coronary arteries of isolated hearts using a self-designed angiography device. The image data were reconstructed into three-dimensional (3D) angiography images using software in the angiography facility. The 3D images were recorded and evaluated by two radiologists and then statistically analysed. The results of PMCTA were consistent with the gold standards for the diagnosis of coronary artery stenosis (P > 0.05). However, water-based contrast media can only be used to examine the pathological changes of blood vessels, which may have limitations in the diagnosis of causes of death such as myocardial oedema. PMCTA can be used as a new method to evaluate the degree of coronary atherosclerosis in addition to traditional autopsy. The 3D reconstruction technique reveals the coronary artery lesions more objectively and vividly and provides the opportunity to re-read the data at any time.

Key points

The methods and parameters for coronary angiography in isolated human hearts were standardized based on the previous researcher.PMCTA in isolated human hearts is including the 3D reconstruction technique that reveals the coronary artery lesions more objectively and vividly, and provides the opportunity to re-read the data at anytime.PMCTA could only be used to examine the pathological changes of blood vessels, which might have limitations for the diagnosis of causes of death.PMCTA in isolated human hearts can be viewed as an auxiliary method for establishing the cause of death, which can provide an assessment of degree and extent of arterial stenosis and accurately help determine the abnormal location.

Application of postmortem computed tomography angiography to settle a medical dispute after aortic dissection surgery: a forensic case report

BACKGROUND

In the present case, we applied postmortem computed tomography angiography (PMCTA) in a medical dispute involving sudden death after cardiovascular surgery.

CASE PRESENTATION

A 39-year-old man underwent aortic arch replacement combined with stented elephant trunk implantation surgery under extracorporeal circulation. All vital signs were stable and he was arranged for discharge seven days after surgery. Several days later, the patient was sent back to the hospital for chest pain and poor appetite. Unfortunately, his condition worsened and he ultimately died. PMCT scanning detect pericardial effusion. Family members suspected that the surgical sutures were not dense enough, causing the patient's postoperative bleeding and resulting in cardiac tamponade and death. PMCTA was performed before autopsy, which showed pericardial effusion. However, postmortem angiography with simulated blood pressure showed no leakage of contrast agent, which guided the subsequent autopsy and histological examinations.

CONCLUSIONS

While many previous postmortem imaging case reports have shown positive results that provided evidence of medical malpractice, the current case excludes the possibility of physician negligence and reasonably settles the medical dispute from another perspective. In short, the PMCTA approach we describe here was an effective tool that can be applied to certain medical-related forensic cases.

Augmented reality in forensics and forensic medicine - Current status and future prospects

Forensic investigations require a vast variety of knowledge and expertise of each specialist involved. With the increase in digitization and advanced technical possibilities, the traditional use of a computer with a screen for visualization and a mouse and keyboard for interactions has limitations, especially when visualizing the content in relation to the real world. Augmented reality (AR) can be used in such instances to support investigators in various tasks at the scene as well as later in the investigation process. In this article, we present current applications of AR in forensics and forensic medicine, the technological basics of AR, and the advantages that AR brings for forensic investigations. Furthermore, we will have a brief look at other fields of application and at future developments of AR in forensics.

Technical note: Semiautomated targeted postmortem computed tomography angiography of the pulmonary arteries using a robotic system

INTRODUCTION

To better depict vascular lesions on postmortem computed tomography (PMCT), whole-body postmortem computed tomography angiography (PMCTA) can be used in forensic diagnostics. Targeted angiography, in which only a specific vessel is filled with contrast agent, might help in cases of traumatic changes that render whole-body PMCTA impossible. Moreover, in targeted PMCTA, the contrast agent does not affect the haptics of any other organs. In this article, we describe automated, CT-guided targeted angiography of the pulmonary artery (PA) using the Virtobot system.

MATERIAL AND METHODS

Our study group consisted of 8 deceased persons (3 males, 5 females). We first performed an unenhanced CT scan and used the data obtained to plan the needle trajectories with the Virtobot planning software. Then, the needle was fully automatically placed by the Virtobot system. Subsequently, 50 ml of contrast agent was injected manually, and the CT scan was repeated (targeted PMCTA).

RESULTS AND DISCUSSION

We tested a new method for performing semiautomated targeted postmortem angiography of the PAs using a robotic needle placement system (Virtobot). In 6 out of our 8 cases, the injection of contrast agent in the PA was successful. In five of the six successful cases, there was reflux of contrast agent to some extent, but the reflux did not affect the readout. In general, the procedure was easy to plan based on a PMCT data set, and the pulmonary trunk was easy to reach with a robotic needle placement system.

Lethal hemorrhage from iliac vein rupture complicating inferior vena cava thrombosis demonstrated by post-mortem CT angiography

Spontaneous iliac vein rupture is a rare cause of retroperitoneal hemorrhage that may present to the forensic pathologist. It has been reported in association with venous thrombosis, anatomical variants such as May-Thurner syndrome, and as a complication of a long-term indwelling IVC filter. It has a female predominance and most often occurs due to rupture of the left iliac vein. This is the first report of the use of post-mortem computed tomography (PMCT) and post-mortem computed tomography angiography (PMCTA) as an adjunct to a conventional autopsy to diagnose rupture of the left iliac vein causing retroperitoneal hemorrhage arising as a complication of an inferior vena cava (IVC) thrombus. We discuss the use of PMCTA as a useful tool in the diagnosis of vascular injury and how it can be used to assist the forensic pathologist. The use of PMCT with PMCTA is an invaluable adjunct to conventional autopsy to diagnose the site of vascular rupture.

Clinical Anatomy and Medical Malpractice-A Narrative Review with Methodological Implications

Anatomical issues are intrinsically included in medico-legal methodology, however, higher awareness would be needed about the relevance of anatomy in addressing medico-legal questions in clinical/surgical contexts. Forensic Clinical Anatomy has been defined as "the practical application of Clinical Anatomy to the ascertainment and evaluation of medico-legal problems". The so-called individual anatomy (normal anatomy, anatomical variations, or anatomical modifications due to development, aging, para-physiological conditions, diseases, or surgery) may acquire specific relevance in medico-legal ascertainment and evaluation of cases of supposed medical malpractice. Here, we reviewed the literature on the relationships between anatomy, clinics/surgery, and legal medicine. Some methodological considerations were also proposed concerning the following issues: (1) relevant aspects of individual anatomy may arise from the application of methods of ascertainment, and they may be furtherly ascertained through specific anatomical methodology; (2) data about individual anatomy may help in the objective application of the criteria of evaluation (physio-pathological pathway, identification-evaluation of errors, causal value, damage estimation) and in final judgment about medical responsibility/liability. Awareness of the relevance of individual anatomy (risk of iatrogenic lesions, need for preoperative diagnostic procedures) should be one of the principles guiding the clinician; medico-legal analyses can also take advantage of its contribution in terms of ascertainment/evaluation.

Post-mortem Computed Tomographic Angiography in Equine Distal Forelimbs: A Feasibility Study

In-depth understanding of pathophysiological processes occurring in the vasculature of the equine distal limb is of great importance to improve both diagnostic and therapeutic approaches to diseases. To gain further insights, a model allowing high-resolution 3D-visualization of the vasculature is necessary. This pilot study evaluated the feasibility of restoring vascular perfusion in frozen-thawed distal equine cadaver limbs without prior preparation using computer tomographic imaging (CT). Five frozen-thawed, radiographically normal forelimbs were perfused with a lipophilic contrast agent through the median artery and radial vein in three phases (arterial, venous, and arterial-venous combined (AVC) dynamic). For comparison, one additional limb was perfused with a hydrosoluble contrast agent. The CT-studies (16-slice MDCT, 140 kV, 200 mA, 2 mm slice thickness, 1 mm increment, pitch 0.688) were evaluated at 11 specified regions for visualization of the vasculature and presence of artifacts or anatomic variations. The protocol used in this study proved to be feasible and provided good visualization (93.1%) of vasculature with low rates of artifacts. During the different phases, vascular visualization was similar, but while filling defects decreased in the later phases, extravasation worsened in the 2 limbs where it was observed. Subjectively, the best quality of angiographic images was achieved during the AVC dynamic phase. Perfusion with hydrosoluble contrast resulted in significantly lower vascular visualization (74.0%) and higher artifact rates. This study shows that reperfusion of frozen-thawed equine distal limbs with a lipophilic contrast agent allows for high-quality 3D-visualization of the vasculature and may serve as a model for in situ vascular evaluation in the future.

Rupture of the Ascending Aorta Surgical Area Detected Using Isolated Cardiopulmonary Organ Computed Tomography Angiography: An Autopsy Case Report After Cardiac Surgery

ABSTRACT

We report cause of death after cardiac surgery using isolated cardiopulmonary organ computed tomography angiography (CTA) and a conventional autopsy. A 56-year-old man underwent aortic valve replacement and coronary artery bypass graft surgery under extracorporeal circulation. Massive bleeding occurred suddenly, and the patient died 25 days later. An autopsy revealed fibrinous exudate in the mediastinum and tight attachment of the pericardium to the heart; there were also clots and inflammatory exudate in the chest cavity. Separating the organs in the chest cavity was difficult, especially in the surgical area. We extracted the heart and lungs together and performed cardiovascular CTA and image reconstruction. Results showed spillage of the contrast agent from the anterior wall of the ascending aorta, approximately 4.5 cm from the replaced aortic valve. A histological examination confirmed that the site of contrast agent spillage was the sutured area of the ascending aorta, which was infected, necrotic, and had ruptured. Using the CTA approach for isolated cardiopulmonary organ imaging can accurately display the location of an aortic rupture, which further guides organ inspection and tissue sampling, and avoids irreversible damage to key regions. In conclusion, the approach we describe can provide evidence for determining cause of death.

A review of visualization techniques of post-mortem computed tomography data for forensic death investigations

Postmortem computed tomography (PMCT) is a standard image modality used in forensic death investigations. Case- and audience-specific visualizations are vital for identifying relevant findings and communicating them appropriately. Different data types and visualization methods exist in 2D and 3D, and all of these types have specific applications. 2D visualizations are more suited for the radiological assessment of PMCT data because they allow the depiction of subtle details. 3D visualizations are better suited for creating visualizations for medical laypersons, such as state attorneys, because they maintain the anatomical context. Visualizations can be refined by using additional techniques, such as annotation or layering. Specialized methods such as 3D printing and virtual and augmented reality often require data conversion. The resulting data can also be used to combine PMCT data with other 3D data such as crime scene laser scans to create crime scene reconstructions. Knowledge of these techniques is essential for the successful handling of PMCT data in a forensic setting. In this review, we present an overview of current visualization techniques for PMCT.

Impact of increasing levels of adaptive statistical iterative reconstruction on image quality in oil-based postmortem CT angiography in coronary arteries

Introduction

Postmortem multi-detector computed tomography (PMCT) has become an important part in forensic imaging. Modern reconstruction techniques such as iterative reconstruction (IR) are frequently used in postmortem CT angiography (PMCTA). The image quality of PMCTA depends on the strength of IR. For this purpose, we aimed to investigate the impact of different advanced IR levels on the objective and subjective PMCTA image quality.

Material and methods

We retrospectively analyzed the coronary arteries of 27 human cadavers undergoing whole-body postmortem CT angiography between July 2017 and March 2018 in a single center. Iterative reconstructions of the coronary arteries were processed in five different level settings (0%; 30%; 50%; 70%; 100%) by using an adaptive statistical IR method. We evaluated the objective (contrast-to-noise ratio (CNR)) and subjective image quality in several anatomical locations.

Results

Our results demonstrate that the increasing levels of an IR technique have relevant impact on the image quality in PMCTA scans in forensic postmortem examinations. Higher levels of IR have led to a significant reduction of image noise and therefore to a significant improvement of objective image quality (+ 70%). However, subjective image quality is inferior at higher levels of IR due to plasticized image appearance.

Conclusion

Objective image quality in PMCTA progressively improves with increasing level of IR with the best CNR at the highest IR level. However, subjective image quality is best at low to medium levels of IR. To obtain a “classic” image appearance with optimal image quality, PMCTAs should be reconstructed at medium levels of IR.

Pulmonary PMCT angiography by right ventricle cardiac puncture: a novel, promising approach for investigating pulmonary thromboembolism

Forensic scholars are paying more attention to postmortem computed tomography (PMCT) and PMCT angiography (PMCTA), which are gradually becoming effective and practical methods in forensic practice. However, few studies have focused on the application of PMCTA to cardiac ventricular puncture-especially of the right ventricle. In this article, we introduce a pulmonary PMCTA approach by right ventricle cardiac puncture and its potential value in fatalities from pulmonary thromboembolism (PTE). The procedure was performed on 11 males and 6 females. PMCT was performed first; then a biopsy core needle was used for percutaneous puncture of the right ventricle under CT guidance. About 400 mL of contrast media was injected at a rate of 50 mL/8 s, followed by CT scanning. Visualization of the pulmonary artery contrast filling was complete in 9 cadavers, and the pulmonary arteries showed significant filling defects in 8 subjects. Unlike in clinical practice, the phenomenon of postmortem coagulation sometimes occurs in the vascular lumina after death. Therefore, the results of these 8 cases can only suggest or be highly suspicious of death from PTE. Then autopsy and histopathological examination confirmed that 4 of the above 8 patients were diagnosed with PTE; the remaining 4 had postmortem clot including chicken fat clot in the pulmonary artery. Pulmonary PMCTA approach is a simple, convenient, and effective method for the visualization of the pulmonary artery, which can be used as an effective auxiliary tool to identify PTE in forensic practice. It will also provide technical support to further investigate PTE imaging characteristics.

Correlation and assessment of coronary artery luminal stenosis: Post-mortem computed tomography angiogram versus histopathology

BACKGROUND

Post-mortem Computed Tomography (PMCT) allows non-invasive or minimally invasive detection of findings that may or may not be visible during conventional autopsy, however, it does not allow the investigator to draw any conclusions regarding patency of the vessel's lumen. To address this deficiency, Post-mortem Computed Tomography Angiography (PMCTA) utilizing different contrast media and techniques have been introduced with various studies looking at the correlation between PMCTA, autopsy (gross) findings and coronary artery histology in diagnosing coronary artery disease.

OBJECTIVES

The aim of this study is to investigate the sensitivity and specificity of PMCTA in diagnosing coronary artery stenosis using water-based contrast media introduced though the vessels of the neck, compared to the gold standard of diagnosis i.e. gross and histological evaluation of the coronary artery.

METHOD

This was a cross sectional study of 158 arterial sections involving 37 subjects recruited from the National Institute of Forensic Medicine (IPFN), Hospital Kuala Lumpur (HKL). An unenhanced PMCT was performed followed by PMCTA using water-based contrast media introduced though the vessels of the neck. Coronary artery stenosis was determined using multiplanar reconstructionD while the degree of stenosis was determined by calculating the percentage of luminal diameter divided by the diameter of the vessel internal elastic.

RESULTS

The analysis of PMCTA and histopathology examinations revealed a sensitivity of 61.5%, specificity of 91.7%; positive predictive value (PPV) of 40.0% and negative predictive value (NPV) of 96.4%.

CONCLUSION

PMCTA utilizing water-based contrast introduced though the vessels of the neck yielded similar results as other methods and techniques of PMCTA. We would therefore conclude that PMCTA utilizing this technique could be used to assess the degree of calcification and the presence of significant stenosis.

Autopsy imaging for aspergillosis in King Penguin, an economically valuable zoo animal

Autopsy imaging (Ai) was performed for a King Penguin. Ai-computed tomography (CT) revealed air sac membrane thickening, multiple nodules in the cranial air sac, suspected abscess, lung infiltration, and air sac contraction. Based on these findings, respiratory disorder was concerned. Aspergillosis, which is the highly observed in penguins, was considered as the primary differential diagnosis. The cultured sample showed characteristic conidial head of Aspergillus spp., the DNA of which was 100% identical to that of A. fumigatus. The cause of death was determined to respiratory failure due to aspergillosis. Ai-CT findings facilitated the dissection workflow and alerted the pathologist to potential hazards during the autopsy. Ai is useful to determine the cause of death and for readiness and safe pathological dissection.

Postmortem imaging as a complementary tool for the investigation of cardiac death

In the past 2 decades, modern radiological methods, such as multiple detector computed tomography (MDCT), MDCT-angiography, and cardiac magnetic resonance imaging (MRI) were introduced into postmortem practice for investigation of sudden death (SD), including cases of sudden cardiac death (SCD). In forensic cases, the underlying cause of SD is most frequently cardiovascular with coronary atherosclerotic disease as the leading cause. There are many controversies about the role of postmortem imaging in establishing the cause of death and especially the value of minimally invasive autopsy techniques. This paper discusses the state of the art for postmortem radiological evaluation of the heart compared to classical postmortem examination, especially in cases of SCD. In SCD cases, postmortem CT is helpful to estimate the heart size and to visualize haemopericardium and calcified plaques and valves, as well as to identify and locate cardiovascular devices. Angiographic methods are useful to provide a detailed view of the coronary arteries and to analyse them, especially regarding the extent and location of stenosis and obstruction. In postsurgical cases, it allows verification and documentation of the patency of stents and bypass grafts before opening the body. Postmortem MRI is used to investigate soft tissues such as the myocardium, but images are susceptible to postmortem changes and further work is necessary to increase the understanding of these radiological aspects, especially of the ischemic myocardium. In postsurgery cases, the value of postmortem imaging of the heart is reportedly for the diagnostic and documentation purposes. The implementation of new imaging methods into routine postmortem practice is challenging, as it requires not only an investment in equipment but, more importantly, investment in the expertise of interpreting the images. Once those requirements are implemented, however, they bring great advantages in investigating cases of SCD, as they allow documentation of the body, orientation of sampling for further analyses and gathering of other information that cannot be obtained by conventional autopsy such as a complete visualization of the vascular system using postmortem angiography.Key pointsThere are no established guidelines for the interpretation of postmortem imaging examination of the heartAt present, postmortem imaging methods are considered as less accurate than the autopsy for cardiac deathsPostmortem imaging is useful as a complementary tool for cardiac deathsThere is still a need to validate postmortem imaging in cardiac deaths by comparing with autopsy findings.

Hospital implementation of minimally invasive autopsy: A prospective cohort study of clinical performance and costs

Objectives

Autopsy rates worldwide have dropped significantly over the last decades and imaging-based autopsies are increasingly used as an alternative to conventional autopsy. Our aim was to evaluate the clinical performance and cost of minimally invasive autopsy.

Methods

This study was part of a prospective cohort study evaluating a newly implemented minimally invasive autopsy consisting of MRI, CT, and biopsies. We calculated diagnostic yield and clinical utility—defined as the percentage successfully answered clinical questions—of minimally invasive autopsy. We performed minimally invasive autopsy in 46 deceased (30 men, 16 women; mean age 62.9±17.5, min-max: 18–91).

Results

Ninety-six major diagnoses were found with the minimally invasive autopsy of which 47/96 (49.0%) were new diagnoses. CT found 65/96 (67.7%) major diagnoses and MRI found 82/96 (85.4%) major diagnoses. Eighty-four clinical questions were asked in all cases. Seventy-one (84.5%) of these questions could be answered with minimally invasive autopsy. CT successfully answered 34/84 (40.5%) clinical questions; in 23/84 (27.4%) without the need for biopsies, and in 11/84 (13.0%) a biopsy was required. MRI successfully answered 60/84 (71.4%) clinical questions, in 27/84 (32.1%) without the need for biopsies, and in 33/84 (39.8%) a biopsy was required. The mean cost of a minimally invasive autopsy was €1296 including brain biopsies and €1087 without brain biopsies. Mean cost of CT was €187 and of MRI €284.

Conclusions

A minimally invasive autopsy, consisting of CT, MRI and CT-guided biopsies, performs well in answering clinical questions and detecting major diagnoses. However, the diagnostic yield and clinical utility were quite low for postmortem CT and MRI as standalone modalities.

"Perimortem" total body CT-scan examination in severely injured children: an informative insight into the causes of death

OBJECTIVE

To report routine practice of "perimortem" CT-scan imaging to determine the causes of death in children dying from severe accidental injuries within the first hours following hospital admission.

SETTINGS

Trauma center of a University Pediatric Hospital.

METHODS

A retrospective study was conducted in children (0 to 15 years old) referred for severe trauma (GCS ≤ 8) to a regional pediatric trauma center, presenting with at least spontaneous cardiac rhythm and dying within the first 12 h after admission. "Perimortem" CT-scan consisted in high-resolution, contrast-enhanced, full-body CT-scan imaging, performed whatever child's clinical status. Lethal and associated lesions found were analyzed and classified according to validated scales. The comparison between clinical and radiological examinations and CT-scan findings evaluated the accuracy of clinical examination to predict lethal lesions.

RESULTS

CT-scan performed in 73 children detected 132 potentially lethal lesions, at least 2 lesions in 63%, and 1 in 37% of the cases. More frequent lethal lesions were brain (43%), and chest injuries (33%), followed by abdominal (12%), and cervical spine injuries (12%). Clinical and minimal radiological examinations were poorly predictive for identifying abdominal/chest lesions. Clinical and imaging data provided to the medical examiner were considered sufficient to identify the cause of death, and to deliver early burial certificates in 70 children. Only three legal autopsies were commanded.

CONCLUSIONS

Perimortem CT imaging could provide an insight into the causes of death in traumatized children. Performed on an emergency basis near death, it eliminates the difficulties encountered in forensic radiology. It could be a possible alternative to full-scale forensic examination, at least regarding elucidation of the potential, or highly probable causes of death.

State of the art in post-mortem computed tomography: a review of current literature

Computed tomography (CT) and other advanced diagnostic imaging techniques are gaining popularity in forensic pathology. This paper aims to define and offer complete and easily accessible "state of the art" for post-mortem computed tomography (PMCT), by reviewing the latest international literature. The proposed format answers the "five Ws" that follows: (1) What: We report the different kinds of CT scan and settings generally used in post-mortem imaging. The machine most employed is a 8/16-slice spiral CT, usually without contrast enhancement. The introduction of some variables, such as CT-guided biopsies, post-mortem ventilation, and PMCT angiography is becoming increasingly useful. (2) Why: Literature highlights the many advantages of PMCT. Limitations can be partly overcome by modern imaging techniques and combined evaluation with traditional autopsy. (3) Who: Most authors agree that collaboration between different specialists, i.e., radiologists and pathologists, is the best scenario, since radiologic, anatomic, and forensic skills are needed simultaneously. The most important human factor is "teamwork". (4) When: Literature provides no absolute limits for performing PMCT. Some authors have tested PMCT as a replacement for conventional autopsy but found some limitations. Others evaluated PMCT as a guide or screening tool for traditional autopsy. (5) Where: Many research groups around the world have performed studies on the use of PMCT. Although few countries adopt PMCT in routine practice, its use is rapidly spreading.

Diagnostic accuracy of postmortem computed tomography, magnetic resonance imaging, and computed tomography-guided biopsies for the detection of ischaemic heart disease in a hospital setting

Aims

The autopsy rate worldwide is alarmingly low (0-15%). Mortality statistics are important, and it is, therefore, essential to perform autopsies in a sufficient proportion of deaths. The imaging autopsy, non-invasive, or minimally invasive autopsy (MIA) can be used as an alternative to the conventional autopsy in an attempt to improve postmortem diagnostics by increasing the number of postmortem procedures. The aim of this study was to determine the diagnostic accuracy of postmortem magnetic resonance imaging (MRI), computed tomography (CT), and CT-guided biopsy for the detection of acute and chronic myocardial ischaemia.

Methods and results

We included 100 consecutive adult patients who died in hospital, and for whom next-of-kin gave permission to perform both conventional autopsy and MIA. The MIA consists of unenhanced total-body MRI and CT followed by CT-guided biopsies. Conventional autopsy was used as reference standard. We calculated sensitivity and specificity and receiver operating characteristics curves for CT and MRI as the stand-alone test or combined with biopsy for detection of acute and chronic myocardial infarction (MI). Sensitivity and specificity of MRI with biopsies for acute MI was 0.97 and 0.95, respectively and 0.90 and 0.75, respectively for chronic MI. MRI without biopsies showed a high specificity (acute: 0.92; chronic: 1.00), but low sensitivity (acute: 0.50; chronic: 0.35). CT (total Agatston calcium score) had a good diagnostic value for chronic MI [area under curve (AUC) 0.74, 95% confidence interval (CI) 0.64-0.84], but not for acute MI (AUC 0.60, 95% CI 0.48-0.72).

Conclusion

We found that the combination of MRI with biopsies had high sensitivity and specificity for the detection of acute and chronic myocardial ischaemia.

Postmortem computed tomography angiography (PMCTA) and traditional autopsy in cases of sudden cardiac death due to coronary artery disease: a systematic review and meta-analysis

INTRODUCTION

Several studies have been performed to assess the efficacy of postmortem computed tomography angiography (PMCTA) in solving cases of sudden cardiac death, even in comparison with the traditional autopsy. However, the results were often inconsistent and inconclusive. Therefore, a global discussion on the subject through a systematic review of the literature and a meta-analysis is necessary.

METHODS

A systematic search of PubMed was performed up to April 23, 2018. Studies exploring the role of PMCTA in cases of sudden cardiac death and the accuracy of this method in diagnosing the cause of death compared to traditional autopsy were included.

RESULTS

The overall sensitivity and specificity of the seven included studies, using conventional autopsy as a reference standard, were 92% and 95%, respectively. The positive and negative likelihood ratios were, respectively, 20.76 (95% CI 1.16-370.2) and 0.08 (95% CI 0.03-0.17), showing that PMCTA represents a strong indicator of the posttest probability of disease. The diagnostic odds ratio and the area under the curve were, respectively, 261.54 (95% CI 1.87-5760.53) and 0.93 (95% CI 0.90-0.95), indicating a high diagnostic power of the test.

CONCLUSION

PMCTA demonstrated a high accuracy in the diagnosis of parietal and luminal coronary changes but was less effective in detecting myocardial ischemia and necrosis. Therefore, the only radiological investigation is often insufficient to determine the cause of sudden death and the conventional autopsy remains the gold standard. However, PMCTA can improve the performance of the autopsy, serving as an aid and guide in the sampling phase for histopathological investigations.

Post-mortem computed tomography improves completeness of the trauma registry: a single institution experience

PURPOSE

To describe our institutional experience with post-mortem computed tomography (PMCT) and its impact on decedent injury severity score (ISS) and to assess the adequacy of emergently placed support medical devices.

METHODS

Over a 5-year period, patients who died at or soon after arrival and have physical exam findings inconsistent with death were candidates for inclusion. Whole body CT was performed without contrast with support medical devices left in place. ISS was calculated with and without the PMCT findings. PMCT results were compared to autopsy findings, if performed. The location of support medical devices was documented.

RESULTS

A total of 38 decedents underwent PMCT, including 53.1% males and a mean age of 42.0 years. Pre-PMCT ISS based on physical exam findings alone was 5.2 (range 0-25), including 16 with ISS = 0. Post-PMCT ISS using the additional imaging data was 50.3 (range 21-75), including 15 with ISS = 50 or greater. Nearly half (47.4%) had at least one support medical device that was either malpositioned or suboptimally positioned, including 26.3% with malpositioned airway devices, 10.3% with malpositioned intra-osseous catheters, and 100% with malpositioned decompressive needle thoracotomies.

CONCLUSIONS

PMCT adds value in identifying injuries that otherwise may have gone undetected in lieu of a formal autopsy, thus creating a more complete trauma registry. The identification of malpositioned support lines and tubes allows for educational feedback to the first responders and trainees. Institutions with a low formal autopsy rate for trauma victims may benefit from developing a PMCT program.

Visualization of Myocardial Infarction in Postmortem Multiphase Computed Tomography Angiography: A Feasibility Study

Recent studies have indicated that multiphase postmortem computed tomography angiography (MPMCTA) allows detection of a pathological enhancement of the myocardium in regions that correlate with the localization of the infarction at histology. The aim of this study was to verify this hypothesis by examining MPMCTA images in cases of myocardial infarction. Therefore, we investigated 10 autopsy cases where death was attributed to myocardial infarction or which showed cardiovascular pathology. As a control group, we selected 10 cases of non-natural (namely, not cardiac) death. The MPMCTA was performed in both groups to ascertain whether a pathological enhancement could be observed. We detected a myocardial enhancement in all cardiac death cases, in the same region that showed infarction at histology. No enhancement was observed in control cases. These results have important implications in the routine management of sudden cardiac death cases. In fact, MPMCTA can not only orient about the cause of death before autopsy, but can especially help to identify affected regions for guiding and improving the sampling for microscopic examination.

Systematic review of surgical training on reperfused human cadavers

BACKGROUND

The role of reperfused human cadavers in surgical training has not been established.

METHODS

Reports describing reperfused human cadaver models in terms of simulated surgeries, the use of tools to assess technical competency and skills transfer to patients, cadaver status and reperfusion techniques were included.

RESULTS

Thirty-five reports were included. Most participants practised vascular (n = 27), flap (n = 6) and trauma (n = 4) procedures. Training progression was evaluated objectively in only two studies. In two publications, flap techniques were practised on cadavers and repeated successfully in patients. Eighteen studies employed whole bodies. Fresh and embalmed cadavers were both used in 17 publications. Most embalmed cadavers were formalin-fixed (n = 10), resulting in stiffness. Few trainings were offered on soft Thiel-embalmed cadavers (n = 5). Only arteries were reperfused in 20 studies, while in 13 publications, the arteries and veins were filled. Arteries and/or veins were mostly pressurized (n = 21) and arterial flow was generated in 14 studies.

CONCLUSIONS

Various reperfused human cadaver models exist, enabling practise of mainly vascular procedures. Preservation method determines the level of simulation fidelity. Thorough evaluation of these models as surgical training tools and transfer effectiveness is still lacking.

Postmortem CT Angiography Compared with Autopsy: A Forensic Multicenter Study

Purpose

To determine if postmortem computed tomography (CT) and postmortem CT angiography help to detect more lesions than autopsy in postmortem examinations, to evaluate the strengths and weaknesses of each method, and to define their indications.

Materials and Methods

Postmortem CT angiography was performed on 500 human corpses and followed by conventional autopsy. Nine centers were involved. All CT images were read by an experienced team including one forensic pathologist and one radiologist, blinded to the autopsy results. All findings were recorded for each method and categorized by anatomic structure (bone, organ parenchyma, soft tissue, and vascular) and relative importance in the forensic case (essential, useful, and unimportant).

Results

Among 18 654 findings, autopsies helped to identify 61.3% (11 433 of 18 654), postmortem CT helped to identify 76.0% (14 179 of 18 654), and postmortem CT angiography helped to identify 89.9% (16 780 of 18 654; P < .001). Postmortem CT angiography was superior to autopsy, especially at helping to identify essential skeletal lesions (96.1% [625 of 650] vs 65.4% [425 of 650], respectively; P < .001) and vascular lesions (93.5% [938 of 1003] vs 65.3% [655 of 1003], respectively; P < .001). Among the forensically essential findings, 23.4% (1029 of 4393) were not detected at autopsy, while only 9.7% (428 of 4393) were missed at postmortem CT angiography (P < .001). The best results were obtained when postmortem CT angiography was combined with autopsy.

Conclusion

Postmortem CT and postmortem CT angiography and autopsy each detect important lesions not detected by the other method. More lesions were identified by combining postmortem CT angiography and autopsy, which may increase the quality of postmortem diagnosis.

Online supplemental material is available for this article.

Study of a seventeenth-century French artificial mummy: autopsical, native, and contrast-injected CT investigations

BACKGROUND

A lead coffin was fortuitously discovered in a church called "Eglise des Toussaints" in Rennes (French Brittany). A collaborative taskforce investigated this extraordinary discovery. A multi-disciplinary team of experts from the National Institute for Preventive Archeological Research (INRAP) and Rangueil University Hospital of Toulouse was created, including anthropologists, archeologists, forensic pathologists, radiologists, and pathologists. The inscription on the lead coffin specified that the body belonged to "Messer Louys de Bruslon, Lord of Plessis," a nobleman who died on November 1, 1661. Multiple holes were visible in the lead coffin, and deterioration threatened the mummy. We opened the lead coffin and discovered an excellently preserved mummy, except for mostly skeletonized upper and lower limbs. The mummy was conserved in several layers of shrouds. Vegetal embalming material covered the head and filled the face, the thorax, and the abdomen. The embalmers had removed all thoracic and abdominal organs and conserved some pelvic organs (e.g., the bladder).

METHODS

Multi-slice computed tomography (MSCT) scanner evaluated the mummy, at each step of our analysis. The excellent preservation of abdominal vascular axes led us to perform a CT angiography using Angiofil®, an oily contrast agent developed for postmortem imaging, before an autopsy.

RESULTS

Sub-diaphragmatic arteries, including the abdominal aorta and iliac arteries, were excellently preserved. The vascular contrast agent filled all arteries. The native CT, CT angiography, and autopsy did not detect any vascular lesion.

CONCLUSION

Our study, based on rare archeological material, allowed a complete examination of an excellently preserved seventeenth-century mummy, using MSCT, angiography, and an autopsy. We did not detect any arterial lesion and proposed a comprehensive description of the embalmment process.

Evolution of post-mortem coronary imaging: from selective coronary arteriography to post-mortem CT-angiography and beyond

Since the 1970s, remarkable efforts have been made in the post-mortem coronary study, especially by angiography, as an added tool to diagnose heart-related deaths. In more recent times, post-mortem CT (PMCT) and post-mortem CT-angiography (PMCTA) have become an established practice in numerous forensic units, because of the undeniable advantages these diagnostic instruments can offer: data acquisition times are increasingly fast, costs have become lower and, once acquired, data can be re-utilized and re-evaluated at any given time. This review aims to chart the history of post-mortem cardiac imaging, highlighting its evolution both in terms of methodology and technology as well as the contribution that forensic radiology has been able to offer to forensic pathology, not as an alternative to autopsy but as a guide and aid when performing one. Finally, the latest advances in the study of cardiac deaths are explored, namely by cardiac post-mortem MRI (PMMR), able to visualize all the various stages of a myocardial infarction, post-mortem MRI-angiography (PMMRA), useful in investigating coronary artery pathology and post-mortem cardiac micro-CT, able to provide near-histological levels of myocardial, coronary and valvular detail.

Forensic Radiology: An Update

Forensic radiology is a specialized area of medical imaging using radiological techniques to assist physicians and pathologists in matters related to the law. The forensic application of diagnostic medical radiology can be applied in many fields; the prime target of evaluation is the osseous skeleton, but soft tissues and abdominal and thoracic viscera may offer key findings. The technological progress in clinical radiology provides a lot of potential tools to forensic radiology, allowing wider fields of applications in this matter.

A guide for effective anatomical vascularization studies: useful ex vivo methods for both CT and MRI imaging before dissection

The objective of this study was to develop a simple and useful injection protocol for imaging cadaveric vascularization and dissection. Mixtures of contrast agent and cast product should provide adequate contrast for two types of ex vivo imaging (MRI and CT) and should harden to allow gross dissection of the injected structures. We tested the most popular contrast agents and cast products, and selected the optimal mixture composition based on their availability and ease of use. All mixtures were first tested in vitro to adjust dilution parameters of each contrast agent and to fine-tune MR imaging acquisition sequences. Mixtures were then injected in 24 pig livers and one human pancreas for MR and computed tomography (CT) imaging before anatomical dissection. Colorized latex, gadobutrol and barite mixture met the above objective. Mixtures composed of copper sulfate (CuSO₄ ) gadoxetic acid (for MRI) and iodine (for CT) gave an inhomogeneous signal or extravasation of the contrast agent. Agar did not harden sufficiently for gross dissection but appears useful for CT and magnetic resonance imaging (MRI) studies without dissection. Silicone was very hard to inject but achieved the goals of the study. Resin is particularly difficult to use but could replace latex as an alternative for corrosion instead of dissection. This injection protocol allows CT and MRI images to be obtained of cadaveric vascularization and anatomical casts in the same anatomic specimen. Post-imaging processing software allow easy 3D reconstruction of complex anatomical structures using this technique. Applications are numerous, e.g. surgical training, teaching methods, postmortem anatomic studies, pathologic studies, and forensic diagnoses.

Post-mortem computed tomography angiography using left ventricle cardiac puncture: A whole-body, angiographic approach

Post-mortem computed tomography (PMCT) and PMCT angiography (PMCTA) are rapidly becoming effective and practical methods in forensic medicine. In this article, the authors introduce a whole-body PMCTA approach involving left ventricle cardiac puncture. This procedure was performed in 9 males and 3 females. PMCT was performed first. Then a biopsy core needle was used for a percutaneous puncture into the left ventricle through the intercostal area under CT guidance. 1000 mL of contrast media (diatrizoate meglumine and normal saline [0.9%] at 1:2 ratio) was injected at a rate of 50 mL/8 s, followed by CT scan. Visualization of systemic arteries was achieved in 11 cases, while only partial visualization was achieved in 1 case, which may have been related to incomplete thawing of the cadaver. PMCTA results revealed no vascular diseases and abnormalities in 10 victims. Among the 10 victims, 4 post-scan autopsies were performed and found no vascular abnormalities, consistent with the PMCTA results. Autopsy of the other 6 victims were refused by the relatives. PMCTA revealed signs of internal carotid artery aneurysm inside the sphenoid sinus in one victim, which was confirmed by autopsy. PMCTA results of another victim showed signs of stenosis and blockage of the distal part of the right vertebral artery and basilar artery. Thromboembolism of those arteries was found during autopsy. Compared with other existing PMCTA methods for examination of vascular injuries and diseases, this technique involves simple procedures, is less time consuming, has lower associated costs, does not require specialized equipment, provides adequate imaging quality, and is suitable for centres not equipped with cardiopulmonary bypass machines or other specialized equipment.