Postmortem Multislice Computed Tomography Research Articles

The approach of virtual autopsy (VIRTOPSY) by postmortem multi-slice computed tomography (PMCT) in China for forensic pathology

Abstract Virtual autopsy (VIRTOPSY) is a non-invasive examination for forensic practice. It can objectively and accurately reflect fractures, soft tissue injuries, wound extent, and organ damage and provides intuitive and powerful court evidence for forensic identification. In recent years, Chinese scholars have investigated the application of VIRTOPSY in forensic analysis of cause of death by collecting cadaveric imaging data representing different causes of death, including falls from height, traffic accidents, burning, drowning, and cardiovascular and cerebrovascular accidents. A cadaver imaging database was initially established. These efforts have promoted the development and application of VIRTOPSY in Chinese forensic practice. In this article, we reviewed some papers published in recent years in forensic science journals domestic and abroad to show the present VIRTOPSY by postmortem multi-slice computed tomography (PMCT) applications in china for forensic pathology.

Postmortem computed tomography and autopsy for detection of lesions and causes of death in gunshot injury cases: a comparative study

BackgroundFirearm injuries are a common cause of death in cases typically investigated by medical examiners. Postmortem multislice computed tomography (PMCT) provides valuable information that enhances the autopsy examination. This study was conducted to compare PMCT and autopsy for the detection of injuries and causes of death in cases of fatal firearm injuries. Thirty cadavers were scanned with PMCT and then underwent autopsy. The results of the two techniques were compared regarding entry wounds, wound channels, detection of foreign bodies, organ and skeletal injuries, and causes of death to determine the concordance or discordance between the two techniques.ResultsThe results revealed excellent agreement between PMCT and autopsy for the detection of injuries and causes of death in cases of gunshot injury. Furthermore, PMCT revealed injuries such as pneumothorax and surgical emphysema that were found to be undetermined by autopsies where the special dissection technique was not part of our routine procedures.ConclusionPMCT could be a valuable complementary tool for autopsies to determine and localize injuries and causes of death in cases of gunshot injury.

Postmortem Computed Tomographic Analysis of Death Caused by Oral Drug Intoxication

Traditional autopsy has changed little in the past century. In Japan, the rate of forensic autopsy in cases of unusual death is very low. Therefore, multi-slice computed tomography (CT) has been used to obtain imaging data instead of or in addition to autopsy in suspicious forensic cases. In our institute, postmortem multi-slice CT has been performed since 2009, and by 2014 there were over 1,000 cases. Our extensive experience with postmortem CT shows that in many cases of death by drug overdose, stomach contents exhibit high X-ray absorption. This article reviews the relationship between CT findings of stomach contents and toxicological analysis results in 23 cases of death by drug overdose. All cases (12 females and 11 males, aged 44 ± 11 years) known to have orally ingested drugs were included in this study. We assessed the slices of all stomach areas on consecutive axial CT images. Twenty cases (87%) showed high X-ray absorption in the stomach, while the other three did not demonstrate radio-dense stomach contents even though drug analysis detected lethal concentrations of drugs in the blood. In conclusion, drugs were frequently, but not always, visualized as contents with high X-ray absorption in the stomach. Postmortem gastric CT images can provide useful information in cases of oral drug intoxication if there are empty drug packages or a suicide note at the death scene. However, precise determination of the cause of death requires full autopsy in cases where there is no indication of suicide at the death scene.

Visualisation of contrast-filled stab wounds in various tissue types with computed tomography

ABSTRACT Background: Stab wounds are common in homicide cases. Post-mortem multislice computed tomography (PMCT) has proved to be a useful tool in forensic examinations of victims of sharp force trauma, but due the limited resolution of soft tissues, the radiological depiction of a stab channel is difficult. In this study, we have tried to obtain information about the shape of a knife blade by CT scanning contrast-filled experimentally inflicted stab wounds in various types of pig tissue. Methodology: The tissue samples were mounted on floral foam (oasis) with wooden sticks. Two contrast media were used: one was unmodified and easy flowing, and one was made more viscous with polyethylene glycol. Stab channels in ballistic soap were used for comparison. India ink-filled stab channels were investigated histologically to determine the pattern of leakage. Principal findings: We found that the shape of the stab wounds on the CT images from lung and muscle tissue did not correspond well to the shape of the inflicting knife. There was a better correspondence in the images obtained from liver, spleen and kidney. The viscous contrast medium was less likely than the thin (easy flowing) contrast medium to spill into to structures outside the stab channel, but some spillage was observed for both types of contrast medium. Air bubbles were only observed in the viscous contrast medium. Conclusion: Radiological evaluation of a contrast-filled stab wound in isolated tissue blocks did not permit the positive identification of the inflicting weapon, but it was, in tissue blocks from liver, spleen and kidney, possible to obtain a rough idea of the shape of the inflicting knife and to differentiate a knife from a screwdriver.

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.

The use of post-mortem computed tomography in the investigation of intentional neonatal upper airway obstruction: an illustrated case

We present a single case report illustrating the diagnostic role of multi-slice computed tomography (MSCT) in the investigation of suspicious child death where mechanical asphyxia is suspected. The case illustrates how radiological findings that may not be observable on conventional plain X-ray were identified by post-mortem MSCT. We illustrate how MSCT can illustrate the position of a foreign body within the upper airway of a neonate without the need for in situ dissection and how the combination of post-mortem MSCT with skeletal survey can provide enhanced diagnostic information in the investigation of not only whether the child was liveborn but also the consideration as to whether or not death has been caused by upper airway obstruction.

Post-mortem imaging of laryngohyoid fractures in strangulation incidents: First results

Fractures and soft-tissue injuries of the neck are of great importance in forensic pathology, as they help in assessing whether strangulation took place, and if so, how severely. In this study, we examined the usefulness of post-mortem imaging with multislice computed tomography (MSCT) in detecting lesions of the laryngohyoid structures and the surrounding soft-tissues. For this purpose, we examined MSCT images of the neck of eight deceased persons who had suffered different types of strangulation and compared the findings with those obtained at the subsequent forensic autopsy. In six of the eight cases (75%), the fracture findings at autopsy were concordant with those found with MSCT. In the two non-congruent cases, MSCT revealed fractures, which were not discovered at autopsy. Soft-tissue haemorrhages were detected by autopsy in five cases, but only in one case with MSCT. MSCT does not suffice in detecting soft-tissue injuries. These preliminary results are promising regarding the detection of fractures in strangulation cases. If these results can be confirmed in larger studies, we believe that post-mortem MSCT may serve – in combination with a thorough external examination and a profound incident-scene investigation – as a useful decision-making tool regarding the necessity of further examinations, i.e. autopsy.

Abdominal Trauma—Sensitivity and Specificity of Postmortem Noncontrast Imaging Findings Compared With Autopsy Findings

The aim of the study was to determine the sensitivity and specificity for typical abdominal injuries after major blunt trauma in postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI). Thirty-four cases of accidental death underwent postmortem pre-autopsy MSCT and MRI. The imaging findings were correlated with the autopsy findings. Sensitivity and specificity for liver injury in computed tomography (CT) alone were 53% and 84%. In MRI, a sensitivity of 58% and a specificity of 46% were found. CT and MRI together (when either one was positive, liver-injury was considered) had a sensitivity of 73% and a specificity of 63%. For major liver lacerations (grades II-VI) a slightly higher sensitivity of 81% and a better specificity of 100% were noted. CT and MRI together showed a sensitivity of 50% for injuries of the spleen, specificity was 89%. CT and MRI together had a sensitivity of only 25% for trauma of the kidney, but a specificity of 100%. A lot of cases with small organ injuries (such as superficial liver-laceration) seemed that could not be found by MSCT or by MRI, leading to a rather low sensitivity. Nevertheless, most of the life-threatening liver injuries could be detected, which is essential in forensic pathology.

Traumatic extra‐axial hemorrhage: Correlation of postmortem MSCT, MRI, and forensic‐pathological findings

To evaluate the diagnostic accuracy of in situ postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) in the detection of primary traumatic extra-axial hemorrhage. Thirty forensic neurotrauma cases and 10 nontraumatic controls who underwent both in situ postmortem cranial MSCT and MR imaging before autopsy were retrospectively reviewed. Both imaging modalities were analyzed in view of their accuracy, sensitivity, and specificity concerning the detection of extra-axial hemorrhage. Statistical significance was calculated using the McNemar test. kappa values for interobserver agreement were calculated for extra-axial hemorrhage types and to quantify the agreement between both modalities as well as MRI, CT, and forensics, respectively. Analysis of the detection of hemorrhagic localizations showed an accuracy, sensitivity, and specificity of 89%, 82%, and 92% using CT, and 90%, 83%, and 94% using MRI, respectively. MRI was more sensitive than CT in the detection of subarachnoid hemorrhagic localizations (P = 0.001), whereas no significant difference resulted from the detection of epidural and subdural hemorrhagic findings (P = 0.248 and P = 0.104, respectively). Interobserver agreement for all extra-axial hemorrhage types was substantial (CT kappa = 0.76; MRI kappa = 0.77). The agreement of both modalitites was almost perfect (readers 1 and 2 kappa = 0.88). CT and MRI are of comparable potential as forensic diagnostic tools for traumatic extra-axial hemorrhage. Not only of forensic, but also of clinical interest is the observation that most thin blood layers escape the radiological evaluation.

Injuries due to sharp trauma detected by post-mortem multislice computed tomography (MSCT): A feasibility study

Modern cross-sectional imaging techniques are being increasingly implemented in forensic pathology. In order to assess the practicability of such a method, namely post-mortem multislice computed tomography (MSCT) in cases of fatal cut and stab injuries, 12 corpses underwent such an examination prior to forensic autopsy. The questions regarding detection of foreign bodies, wound channels, skeletal and organ injuries, as well as the cause of death were addressed at MSCT and autopsy. The results of the two techniques revealed that post-mortem MSCT a useful tool in the assessment of such injuries.

Unusually extensive head trauma in a hydraulic elevator accident: Post-mortem MSCT findings, autopsy results and scene reconstruction

Accidental or intentional falls from a height are a form of blunt trauma and occur frequently in forensic medicine. Reports describing elevator accidents as a small subcategory of falls from heights are rare in the medical literature and no report on injury patterns or scene reconstruction of such an accident was found. A case of an accident in a hydraulic elevator with a man falling 3m was examined using post-mortem multi-slice computed tomography (MSCT) and autopsy. The man suffered an unusually extensive trauma and died at the scene. Post-mortem MSCT examination showed a comminute fracture of the skull, the right femur and the first lumbar vertebra. Severe lacerations of the brain with epidural, subdural and subarachnoidal haemorrhages over both hemispheres were diagnosed. Autopsy confirmed these findings. To reconstruct the accident we used radiological and autopsy results as well as findings at the scene.

Gunshot injuries detected by post-mortem multislice computed tomography (MSCT): A feasibility study

Modern cross-sectional imaging techniques are being increasingly implemented in forensic pathology. These methods may serve as an adjuvant to classic forensic autopsies or even replace them altogether in the future. In order to assess the practicability of such a method, namely post-mortem multislice computed tomography (MSCT) in fatal gunshot injuries, 22 corpses underwent such an examination prior to forensic autopsy. The cardinal questions of the location of entrance and exit wounds, the detection of bullets and bullet fragments in the body, the bullet course, inflicted injuries and cause of death were addressed at MSCT and autopsy. The results of the two techniques revealed that post-mortem MSCT can answer these questions reliably and is therefore a useful tool in the assessment of such injuries.

Heart Luxation and Myocardium Rupture in Postmortem Multislice Computed Tomography and Magnetic Resonance Imaging

Postmortem cross-sectional imaging in situ of nontraumatic human heart and of the heart with a penetrating trauma has already been described. In postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) the diagnosis of blunt trauma to the heart was reported to be challenging. We examined a case of fatal vehicle accident with severe heart trauma, which underwent postmortem MSCT and MRI before autopsy. Both radiologic methods showed dislocation of the heart. Based on this finding a rupture of the pericardium was suspected. T2-weighted MRI sequence and MSCT images allowed for diagnosis of myocardium rupture. We conclude that postmortem MSCT and MRI performed in suspicion of blunt trauma to the heart in forensic cases are useful documentation and diagnostic tools.

New identification possibilities with postmortem multislice computed tomography

Historically, radiographical identification has been done by comparing conventional antemortem and postmortem X-ray images. The advent of new technologies such as multislice computed tomography (MSCT) is making traditional antemortem examination increasingly less frequent. The authors present the results of MSCT study of 35 corpses, which demonstrated features potentially useful for identification purposes in ten cases. These features, which relate to abnormalities of postcranial bone as well as of the internal organs, are presented. Attempts were made to find any antemortem X-rays or MSCTs on the cases described to compare the two antemortem and postmortem images. Although antemortem imaging was recovered for only two cases (one case with a skeletal abnormality and one case with a visceral abnormality), it permitted for both cases the comparison of antemortem and postmortem MSCTs.

Drowning—post-mortem imaging findings by computed tomography

The aim of this study was to identify the classic autopsy signs of drowning in post-mortem multislice computed tomography (MSCT). Therefore, the post-mortem pre-autopsy MSCT- findings of ten drowning cases were correlated with autopsy and statistically compared with the post-mortem MSCT of 20 non-drowning cases. Fluid in the airways was present in all drowning cases. Central aspiration in either the trachea or the main bronchi was usually observed. Consecutive bronchospasm caused emphysema aquosum. Sixty percent of drowning cases showed a mosaic pattern of the lung parenchyma due to regions of hypo- and hyperperfused lung areas of aspiration. The resorption of fresh water in the lung resulted in hypodensity of the blood representing haemodilution and possible heart failure. Swallowed water distended the stomach and duodenum; and inflow of water filled the paranasal sinuses (100%). All the typical findings of drowning, except Paltau's spots, were detected using post-mortem MSCT, and a good correlation of MSCT and autopsy was found. The advantage of MSCT was the direct detection of bronchospasm, haemodilution and water in the paranasal sinus, which is rather complicated or impossible at the classical autopsy.

Digital forensic osteology—Possibilities in cooperation with the Virtopsy ® project

The present study was carried out to check whether classic osteometric parameters can be determined from the 3D reconstructions of MSCT (multislice computed tomography) scans acquired in the context of the Virtopsy ® project. To this end, four isolated and macerated skulls were examined by six examiners. First the skulls were conventionally (manually) measured using 32 internationally accepted linear measurements. Then the skulls were scanned by the use of MSCT with slice thicknesses of 1.25 mm and 0.63 mm, and the 33 measurements were virtually determined on the digital 3D reconstructions of the skulls. The results of the traditional and the digital measurements were compared for each examiner to figure out variations. Furthermore, several parameters were measured on the cranium and postcranium during an autopsy and compared to the values that had been measured on a 3D reconstruction from a previously acquired postmortem MSCT scan. The results indicate that equivalent osteometric values can be obtained from digital 3D reconstructions from MSCT scans using a slice thickness of 1.25 mm, and from conventional manual examinations. The measurements taken from a corpse during an autopsy could also be validated with the methods used for the digital 3D reconstructions in the context of the Virtopsy ® project. Future aims are the assessment and biostatistical evaluation in respect to sex, age and stature of all data sets stored in the Virtopsy ® project so far, as well as of future data sets. Furthermore, a definition of new parameters, only measurable with the aid of MSCT data would be conceivable.

Intrahepatic Gas at Postmortem Computed Tomography: Forensic Experience as a Potential Guide for In Vivo Trauma Imaging

Until August 2004 there were 106 forensic cases examined with postmortem multislice computed tomography (MSCT) and magnetic resonance (MR) imaging before traditional autopsy within the Virtopsy project. Intrahepatic gas (IHG) was a frequent finding in postmortem MSCT examinations. The aim of this study was to investigate its cause and significance. There were 84 virtopsy cases retrospectively investigated concerning the occurrence, location, and volume of IHG in postmortem MSCT imaging (1.25 mm collimation, 1.25 mm thickness). We assessed and noted the occurrence of intestinal distention, putrefaction, and systemic gas embolisms and the cause of death, possible open trauma, possible artificial respiration, and the postmortem interval. We investigated the relations between the findings using the contingency table (chi2 test) and the comparison of the postmortem intervals in both groups was performed using the t test in 79 nonputrefied corpses. IHG was found in 47 cases (59.5%). In five of the cases, the IHG was caused or influenced by putrefaction. Gas distribution within the liver of the remaining 42 cases was as follows: hepatic arteries in 21 cases, hepatic veins in 35 cases, and portal vein branches in 13 cases; among which combinations also occurred in 20 cases. The presence of IHG was strongly related to open trauma with systemic gas. Pulmonary barotrauma as occurring under artificial respiration or in drowning also caused IHG. Putrefaction did not seem to influence the occurrence of IHG until macroscopic signs of putrefaction were noticeable. IHG is a frequent finding in traumatic causes of death and requires a systemic gas embolism. Exceptions are putrefied or burned corpses. Common clinical causes such as necrotic bowel diseases appear rarely as a cause of IHG in our forensic case material.

Post-mortem forensic neuroimaging: Correlation of MSCT and MRI findings with autopsy results

Multislice-computed tomography (MSCT) and magnetic resonance imaging (MRI) are increasingly used for forensic purposes. Based on broad experience in clinical neuroimaging, post-mortem MSCT and MRI were performed in 57 forensic cases with the goal to evaluate the radiological methods concerning their usability for forensic head and brain examination. An experienced clinical radiologist evaluated the imaging data. The results were compared to the autopsy findings that served as the gold standard with regard to common forensic neurotrauma findings such as skull fractures, soft tissue lesions of the scalp, various forms of intracranial hemorrhage or signs of increased brain pressure. The sensitivity of the imaging methods ranged from 100% (e.g., heat-induced alterations, intracranial gas) to zero (e.g., mediobasal impression marks as a sign of increased brain pressure, plaques jaunes). The agreement between MRI and CT was 69%. The radiological methods prevalently failed in the detection of lesions smaller than 3 mm of size, whereas they were generally satisfactory concerning the evaluation of intracranial hemorrhage. Due to its advanced 2D and 3D post-processing possibilities, CT in particular possessed certain advantages in comparison with autopsy with regard to forensic reconstruction. MRI showed forensically relevant findings not seen during autopsy in several cases. The partly limited sensitivity of imaging that was observed in this retrospective study was based on several factors: besides general technical limitations it became apparent that clinical radiologists require a sound basic forensic background in order to detect specific signs. Focused teaching sessions will be essential to improve the outcome in future examinations. On the other hand, the autopsy protocols should be further standardized to allow an exact comparison of imaging and autopsy data. In consideration of these facts, MRI and CT have the power to play an important role in future forensic neuropathological examination.

Gas embolism following intraosseous medication application proven by post-mortem multislice computed tomography and autopsy

The post-mortem use of modern imaging techniques such as multislice computed tomography (MSCT) is becoming increasingly important as an aid for conventional autopsy. This article presents a case of a 4-month-old boy who died from sudden infant death syndrome (SIDS) with intravascular gas after an intraosseus medication application documented by post-mortem MSCT. It is most likely that the gas entered the body during resuscitation. This case emphasises the advantage of post-mortem imaging as a complementary aid for the autopsy. We conclude that during emergency treatment, the medical staff should be aware of the possibility of causing a gas embolism following intraosseus medication. Resuscitation with an inserted, disconnected intraosseous needle should be avoided.

Application of 3D documentation and geometric reconstruction methods in traffic accident analysis: With high resolution surface scanning, radiological MSCT/MRI scanning and real data based animation

The examination of traffic accidents is daily routine in forensic medicine. An important question in the analysis of the victims of traffic accidents, for example in collisions between motor vehicles and pedestrians or cyclists, is the situation of the impact. Apart from forensic medical examinations (external examination and autopsy), three-dimensional technologies and methods are gaining importance in forensic investigations. Besides the post-mortem multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) for the documentation and analysis of internal findings, highly precise 3D surface scanning is employed for the documentation of the external body findings and of injury-inflicting instruments. The correlation of injuries of the body to the injury-inflicting object and the accident mechanism are of great importance. The applied methods include documentation of the external and internal body and the involved vehicles and inflicting tools as well as the analysis of the acquired data. The body surface and the accident vehicles with their damages were digitized by 3D surface scanning. For the internal findings of the body, post-mortem MSCT and MRI were used. The analysis included the processing of the obtained data to 3D models, determination of the driving direction of the vehicle, correlation of injuries to the vehicle damages, geometric determination of the impact situation and evaluation of further findings of the accident. In the following article, the benefits of the 3D documentation and computer-assisted, drawn-to-scale 3D comparisons of the relevant injuries with the damages to the vehicle in the analysis of the course of accidents, especially with regard to the impact situation, are shown on two examined cases.