Article

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

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Abstract

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 3mm 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.

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... Clinical radiologists with only a short course in forensic pathology and the inclusion of children may bias the findings of Yen et al. [25]. In the study by Hoey et al., 160 fatalities occurred, but no information on the criteria for ordering autopsy were provided, which may introduce bias [26]. ...
... Clinical radiologists evaluated the images in all studies except the three Danish studies, which were evaluated by forensic pathologists. Only two studies explicitly state the use of checklists for radiology reporting [25,31], and in all but two studies [26,32], the evaluators were blinded to autopsy findings, though evaluators generally were aware of circumstances of death. ...
... Yen et al. investigated cases of "routine" work [25]. Seven were gunshot fatalities, and 26 were traffic or aircraft fatalities. ...
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Article
Post-mortem computed tomography (PMCT) has been increasingly used as routine examination in forensic pathology. No recent review of the growing number of papers on the ability of PMCT to detect skull fracture exists, and original papers report sensitivities from 0.85 to 1.00. This systematic review (PROSPERO: CRD42021233264) aims to provide a meta-analysis of sensitivity and specificity of PMCT in skull fracture detection. We searched PubMed, MEDLINE and Embase for papers published between January 2000 and August 2021 reporting raw numbers, sensitivity and specificity or Abbreviated Injury Score for PMCT compared to autopsy. Papers without both PMCT and autopsy, no separate reporting of the neuro-cranium, exclusively on children, sharp trauma, gunshot or natural death as well as case reports and reviews were excluded. Two authors independently performed inclusion, bias assessment and data extraction. QUADAS-2 was used for bias assessment and a random effects models used for meta-analysis. From 4.284 hits, 18 studies were eligible and 13 included in the meta-analysis for a total of 1538 cases. All deceased were scanned on multi-slice scanners with comparable parameters. Images were evaluated by radiologists or pathologists. Intra- and inter-observer analyses were rarely reported. In summary, sensitivity of PMCT for detection of fractures in the skull base was 0.87 [0.80; 0.92] with specificity 0.96 [0.90; 0.98], and sensitivity for the vault was 0.89 [0.80; 0.94] with specificity 0.96 [0.91; 0.98]. The mixed samples are a limitation of the review.
... The location, shape, and extent of fracture systems provide information on the direction of impact, number of impacts, force of impact, and shape of the impacting object. Several papers have compared PMCT to autopsy for skull fracture detection [16][17][18][19][20][21][22] and found sensitivities ranging from 0.67 to 1.00 and specificities ranging from 0.66 to 1.00, with the majority of studies reporting values above 0.90 for both. Methodologically, these studies consider the base and the vault separately, and the presence of any fracture system, no matter the number of fractures or the extent of fracture systems, constitutes a single positive finding, i.e. a fracture is either present or absent. ...
... The sensitivity and specificity of all four individual observers were comparable, as seen in Table 13. With the methods of prior publications [16][17][18][19][20][21][22], considering the presence or absence of a fracture system, we found a sensitivity of 0.97 for the vault and 0.93 for the base. Specificity would have been 0.58 for the vault and 0.45 for the base. ...
... Post mortem radiology lies between the specialties of pathology and radiology. In studies on forensic PMCT, a radiologist is most commonly the interpreter [2], and it is generally advised that radiologists are trained in forensic pathology [16,32,41]. Radiologists trained in forensic pathology and forensic pathologists trained in radiology may be equally proficient [42], though Leth et al. found a kappa of 0.33 for injuries in the skeletal system and of 0.74 for injuries in the head region when comparing Abbreviated Injury Score (AIS) determined at PMCT by a radiologist and a pathologist [41]. ...
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Article
Post–mortem computed tomography (PMCT) is a routine tool in many forensic pathology departments as it is fast and non-destructive and allows less gruesome visualization than photographs, and the images are indefinitely storable. Several studies investigated congruence between PMCT and autopsy for skull fracture but registered only the presence or absence of fracture systems. The objective of this study was to determine location-specific sensitivity and specificity of PMCT for individual fracture lines in blunt force head trauma. Accurate 3D models based on PMCT data with all fracture lines visible are important for future studies on fractures, applying finite element analysis (FEA). We retrospectively sampled adult cases from 2013 to 2019 with skull fracture mentioned in the autopsy report. PMCT was on a Siemens 64-slice scanner and autopsy according to international guidelines. The location and direction of all fracture lines at autopsy and at de novo interpretation of scans were registered and compared. Ninety-nine cases with 4809 individual findings were included. Age ranged from 18 to 100 years. The overall sensitivity was 0.58, and specificity was 0.91. For individual locations, sensitivity ranged from 0.24 to 0.85, and specificity ranged from 0.73 to 1.00. Intra-observer agreement was 0.74, and inter-observer agreement ranged from 0.43 to 0.58. In conclusion, PMCT is suited for detection of fracture systems, but not for detection of all individual fracture lines. Our results differed from the existing literature due to the methodological choices of registering individual fracture lines. Future studies utilising FEA must supplement PMCT with autopsy data.
... Careful evaluation of these sequences will help differentiate hemorrhage from other causes of hyperattenuation on CT such as calcifications or highly vascular tumors. In a retrospective study involving 57 cadavers conducted to correlate postmortem forensic neuroimaging with autopsy results, MRI and CT imaging showed a sensitivity of 63% in the detection of hemorrhages in the white matter [71]. Moreover, postmortem MRI and postmortem CT were superior to the autopsy in the evaluation of intraventricular hemorrhage [71]. ...
... In a retrospective study involving 57 cadavers conducted to correlate postmortem forensic neuroimaging with autopsy results, MRI and CT imaging showed a sensitivity of 63% in the detection of hemorrhages in the white matter [71]. Moreover, postmortem MRI and postmortem CT were superior to the autopsy in the evaluation of intraventricular hemorrhage [71]. Additionally, regarding the cause of death, brain CT and MRI showed an overall good correlation with autopsy [71]. ...
... Moreover, postmortem MRI and postmortem CT were superior to the autopsy in the evaluation of intraventricular hemorrhage [71]. Additionally, regarding the cause of death, brain CT and MRI showed an overall good correlation with autopsy [71]. ...
Article
Sudden unexpected death due to central nervous system (CNS)-related pathologies though far less common than cardiac causes still account for a substantial proportion of sudden deaths that occur worldwide. This review covers the most common causes of sudden unexpected death due to CNS-related pathologies encountered by forensic pathologists. These include intracerebral hemorrhage, aneurysmal subarachnoid hemorrhage, ischemic stroke, epilepsy, brain tumors, and infectious causes. Related rare causes are not discussed and are beyond the scope of this review. The role of neuroimaging and genetic testing as autopsy ancillary investigations in such sudden deaths is also discussed.
... In the first days after death, there is no relevant difference in radiological appearance in most findings in ante-or postmortem brains [76]. However, Berger et al. demonstrated in 2015 that subdural hematomas became denser and shrank postmortem; thus, their appearance changes. ...
... Therefore, it is advantageous to be familiar with pitfalls in the imaging interpretation of intracranial hemorrhages for both the living and deceased. Although postmortem imaging might have a different radiological appearance than clinical imaging, the overall specificity for intra-and extraaxial brain findings without putrefaction compared to autopsy was 94% for PMCT and PMMR [76]. ...
... Above mentioned PMMR is a powerful diagnostic tool in diagnosing intracranial hemorrhage; it is more sensitive than PMCT in the detection of subarachnoid hemorrhagic localizations, whereas no significant difference resulted from the detection of epidural and subdural hemorrhagic findings [5,78]. Furthermore, detection of intraventricular hemorrhage by PMCT or PMMR is superior to autopsy [76]. Extraaxial hemorrhages were visible on both PMMR and PMCT in approximately 90% of all cases. ...
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Article
Radiological findings of natural causes of death in adults in postmortem imaging are of enormous value for medicolegal investigation. Postmortem computed tomography (PMCT) in particular is increasingly used as a triage tool after external inspection and before a full autopsy. Forensic pathologists and radiologists commonly deal with a wide variety of deaths from natural causes. The most common encountered natural causes of death refer to the cardiovascular, central nervous, respiratory, gastrointestinal and metabolic system. This review provides an overview of the literature on postmortem imaging of the major natural causes of death in adults, categorized by organ systems.
... Our results, in accordance with Yen et al, 14 suggest that PMCT may be unreliable in identifying skin lesions. However, due to the small number of lesions present in the current study, more research is necessary for definitive conclusions to be drawn. ...
... According to the literature, the agreement between PMCT and autopsy is high for calvarium fractures, 19 and PMCT can even be superior to autopsy in detecting facial bone fractures. 14,20 However, several authors [21][22][23] have observed that PMCT is less reliable than autopsy in identifying basilar skull fractures: acute nondisplaced fractures of the skull base without significant underlying hemorrhage can sometimes be missed on CT. Of note, in our case series, there were no cranial fractures of the skull base, so it was not possible to assess the ability of CT in identifying fractures in that area. ...
... In one of our cases, massive congestion of the vessels was misinterpreted by the radiologist as subarachnoid hemorrhage, a possibility well recognized in the literature. 14,26 According to other authors, [27][28][29][30] changes in the density of the dura and anoxia can also be mistakenly visualized on CT scans as subarachnoid hemorrhages. ...
Article
The use of post-mortem computed tomography (PMCT) to support autopsy pathology has increased in recent decades. To some extent, PMCT has also been contemplated as a potential alternative to conventional post-mortem examination. The purpose of this study was to investigate the ability of PMCT to detect specific pathologic findings in the head and brain in natural hospital deaths. We examined post-mortem CT images and autopsy data from 31 subjects who died at SUNY (State University of New York) Upstate University Hospital between 2013-2018. Each subject underwent a non-contrast PMCT and a traditional autopsy. A neuroradiologist analyzed PMCT images for head and brain abnormalities. The autopsies were performed by pathologists who were aware of the radiology results. In our series, PMCT was able to detect the majority of the significant space-occupying lesions, although it was not always reliable in ascertaining their nature. PMCT revealed findings usually challenging to detect at autopsy. Unfortunately, there were also situations in which PMCT was misleading, showing changes that were difficult to interpret, or that could be related to post-mortem events. Therefore, we conclude PMCT should be used as an adjunct rather than a substitute to autopsy.
... Though, the accuracy of these methods was either not ascertained or demonstrated inferior to autopsy [2,24,30,33,34,39,41,44,50] (levels [2][3][4][5]. Even if PMMR imaging turned out to be superior to PMCT in identifying extra-cranial lesions, it performed anyhow still worse than autopsy [51] (level 2). ...
... About the cause of death, PMCT identified all lethal GSW in 13 cases [22] (level 2), showed a sensibility of 88% [89] (level 2) and easily detected deaths due to blood aspiration being even superior to autopsy for air-connected lesions (e.g. gas embolism) [2,22,29,31,38,44,48,51,55,74] (levels [2][3][4][5]. However, the mere presence of vascular bubbles is not diagnostic [44] (level 4) and PMCT accuracy in detecting and differentiating parenchymal gunshot lesions from postmortem changes is lower than the one of autopsy or MRI [2,9,32,43,48,51,66,84] (levels 2-5). ...
... gas embolism) [2,22,29,31,38,44,48,51,55,74] (levels [2][3][4][5]. However, the mere presence of vascular bubbles is not diagnostic [44] (level 4) and PMCT accuracy in detecting and differentiating parenchymal gunshot lesions from postmortem changes is lower than the one of autopsy or MRI [2,9,32,43,48,51,66,84] (levels 2-5). In particular, unfortunately, PMCT is especially inaccurate for vascular injuries, regardless of readers' expertise [22,30,48] (levels 2-4). ...
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Article
Introduction Despite the constantly growing popularity of radiological imaging in forensic pathology, a systematic review investigating the efficiency and limits of radiological techniques, in comparison to forensic autopsy, was still missing. Aim The present review aims at providing an overview on the current role of radiology in the forensic investigation of fatal gunshot wounds without any restriction to specific radiological techniques. Material and methods A systematic literature search on three databases (PubMed, Web of Science, and Science Direct) was performed until December 2017. The Oxford Centre for Evidence Based Medicine (OCEBM) grading system for levels of evidence was applied, in order to weigh published evidence. Results and discussion Eighty-six papers (1.64% of the records) were included. Despite the quite limited general level of evidence, which contrasts with the abundance of the scientific literature on this topic, several recommendations/statements, coupled to their OCEBM grade, were distilled as for the identification of retained bullets, gunshot wounds detection, diagnosis of entrance and exit wounds, trajectories and internal injury detection and estimation of the firing distance. Conclusions Imaging radiological technologies represent the present and future of wound ballistics. However, traditional, micro and molecular imaging techniques require further validation through blinded cross-sectional studies with appropriate reference standards (e.g. forensic autopsy).
... traffic, sports, work and domestic accidents, falls) and aggressions (e.g. physical abuse of children, injuries from bladed weapons or firearms in young adults) [2]. Autopsy is the gold standard for postmortem evaluation of traumatic head injuries, but it is invasive, operator-dependent and irreversible. ...
... When exploring trauma caused by firearms, PMCT can provide valuable additional information on localization of projectiles, entry and exit points, and ballistic trajectory [8]. While some PMCT-autopsy correlation studies have been performed for full-body trauma [9][10][11][12], others have focused on the cranial region [2,8,[13][14][15], with PMCT being read by radiologists [2,13,15] or by forensic pathologists [14]. These studies showed that PMCT is superior to autopsy in detecting pneumocephalus, intraventricular hemorrhages and facial skeleton fractures [2], but that the detection of small hemorrhagic injuries [2,13,15] and injuries of the skull base [2,8], especially fractures of the anterior and middle cranial fossa [14], are part of its main limitations. ...
... When exploring trauma caused by firearms, PMCT can provide valuable additional information on localization of projectiles, entry and exit points, and ballistic trajectory [8]. While some PMCT-autopsy correlation studies have been performed for full-body trauma [9][10][11][12], others have focused on the cranial region [2,8,[13][14][15], with PMCT being read by radiologists [2,13,15] or by forensic pathologists [14]. These studies showed that PMCT is superior to autopsy in detecting pneumocephalus, intraventricular hemorrhages and facial skeleton fractures [2], but that the detection of small hemorrhagic injuries [2,13,15] and injuries of the skull base [2,8], especially fractures of the anterior and middle cranial fossa [14], are part of its main limitations. ...
Article
Introduction: The aim of this study was to assess the agreement between postmortem computed tomography (PMCT) and autopsy in detecting traumatic head injuries. Materials and methods: Consecutive cases of death that underwent both unenhanced PMCT and conventional autopsy were collected from our institution database during a period of 3 years and reviewed retrospectively. PMCT images were reviewed for the presence of fractures (cranial vault, skull base, facial bones and atlas/axis) and intracranial hemorrhage. Kappa values were calculated to determine the agreement between PMCT and autopsy reports. Results: 73 cases were included, of which 44 (60%) had head trauma. Agreement between PMCT and autopsy was almost perfect (κ = 0.95) for fractures and substantial (κ = 0.75) for intracranial hemorrhage. PMCT was superior to autopsy in detecting facial bone and upper cervical spine fractures, and intraventricular hemorrhage. However, in some cases thin extra-axial blood collections were missed on PMCT. Conclusions: The agreement between PMCT and autopsy in detecting traumatic head injuries was good. Using a combination of both techniques increases the quality of postmortem evaluation because more lesions are detected.
... Нативная КТ обладает достаточно высокой чувствительностью и специфичностью при острой ЧМТ (рис. 5) [60][61][62]. ...
... Тот же случай. Разрез мозга по Flechsig совпадает с КТ-срезом [62]. ...
... В другой очень интересной работе K.Yen и соавт. [62] по посмертной визуализации ЧМТ сравнивали результаты КТ и МРТ с последующей традиционной аутопсией. В этом ретроспективном исследовании авторы изучали результаты деятельности клинических рентгенологов (не проходивших специальную подготовку), описывающих посмертные КТ-и МР-изображения 57 трупов. ...
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Article
Purpose of the study. The review analyzed the results of studies on the use of computed tomography (CT) and magnetic resonance imaging (MRI) in a forensic expertise (FE) of the adults. The purpose of this review is to introduce forensic radiologists and situations, the most common in postmortem imaging, as well as its strengths and weaknesses. Material and methods. The basic Internet resources used: Russian Scientific Electronic Library (elibrary.ru), Embase, Medline, Web of Science, Cochrane database. Results and conclusions. Methods for FE postmortem imaging are under active study and formation of the evidence base. "The gold standard" postmortem diagnosis is a traditional autopsy. But the role of tomographic methods of research is growing. For practical purposes, the FE adult cadavers more suitable for CT. In some cases, autopsy should be combined with different methods of beam diagnostics - CT, CT angiography and MRI. Posthumous ray diagnosis can be of great help in the visualization of mechanical damage, as well as to determine the cause in some cases, sudden death. Posthumous imaging may be required in some other common situations in the practice of FE: mechanical asphyxia, drowning, action of high and low temperature, research rotten modified and unidentified bodies, detection of foreign bodies.
... Moreover, particular applications for PMMRI such as diffusion weighted imaging and brain tissue quantification showed to be feasible for estimating early post-mortem intervals and determination of cause of death in some cases [12][13][14]. Post-mortem MR Neuroimaging results in advanced putrefaction have been mentioned in the literature correlating autopsy, CT, and MRI findings [15][16][17]. However, those studies mainly focused on isolated cases with advanced putrefaction. ...
... The results of the present study indicate that superiority of PMMRI compared to PMCT and autopsy increases with advancing putrefaction and brain liquefaction. Yen et al. demonstrated that in fresh corpses PMCT and PMMRI were both satisfying for evaluation of intracranial hemorrhage compared to autopsy [16]. The present study indicates that diagnostic neuroimaging conditions may significantly change in advanced putrefied cases, and assessment of intracranial hemorrhage may only be possible with PMMRI in liquefied brains. ...
... The influence of temperature changes on PMMR image quality was not investigated. Previous work demonstrated that image quality in PMMRI may be altered due to different and particularly low corpse temperatures [3,8,14,16]. In the present study, the observed temperature range between corpses was 7°C at maximum and the mean temperature was 21.2°C. ...
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Article
Introduction Putrefaction of the brain is a challenge to a forensic pathologist because it may lead to considerable organ alterations and restrict documenting reliable autopsy findings. Objectives This study aims to present a new and systematic evaluation of possible benefits of post-mortem MR Neuroimaging (1.5 Tesla, sequences: T1w, T2w) in putrefied corpses in comparison to PMCT and autopsy. Methods A post-mortem MRI brain examination was conducted on 35 adult, putrefied corpses after performing a whole body CT scan prior to a forensic autopsy. Imaging data and autopsy findings were compared with regard to brain symmetry, gray and white matter junction, ventricular system, basal ganglia, cerebellum, brain stem, and possible pathological findings. Results At autopsy, a reliable assessment of the anatomical brain structures was often restricted. MR imaging offered an assessment of the anatomical brain structures, even at advanced stages of putrefaction. In two cases, MR imaging revealed pathological findings that were detectable neither by CT scans nor at autopsy. Conclusions Post-mortem MR imaging of putrefied brains offers the possibility to assess brain morphology, even if the brain is liquefied. Post-mortem MR imaging of the brain should be considered if the assessment of a putrefied brain is crucial to the evaluation of a forensic autopsy case.
... Recently, postmortem imaging, including postmortem computed tomography (PMCT) and postmortem magnetic resonance imaging (PMMR), has been introduced to the field of forensic pathology [8][9][10][11][12][13]. Postmortem imaging of the head region has been performed in previous studies to report on the detection of various findings in cases of trauma-related intra-or extracranial injury, including haemorrhage, fracture, oedema, and herniation [14][15][16], arteriovenous malformation-related intracerebral haemorrhage [17], cerebral infarction [11,14], ischaemic white matter changes [18], and air embolism [19,20]. However, the findings of postmortem imaging of brain lesions related to CO poisoning have not been reported previously. ...
... Recently, postmortem imaging, including postmortem computed tomography (PMCT) and postmortem magnetic resonance imaging (PMMR), has been introduced to the field of forensic pathology [8][9][10][11][12][13]. Postmortem imaging of the head region has been performed in previous studies to report on the detection of various findings in cases of trauma-related intra-or extracranial injury, including haemorrhage, fracture, oedema, and herniation [14][15][16], arteriovenous malformation-related intracerebral haemorrhage [17], cerebral infarction [11,14], ischaemic white matter changes [18], and air embolism [19,20]. However, the findings of postmortem imaging of brain lesions related to CO poisoning have not been reported previously. ...
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Article
A man and a woman were found dead in the same car with a burned coal briquette. The cause of death of the woman was assigned to acute carbon monoxide (CO) poisoning without difficulty based on typical findings associated with this condition, including elevation of carboxyhaemoglobin (COHb). However, the man had an unremarkable elevation of COHb and a higher rectal temperature compared to that of the woman. Postmortem computed tomography (PMCT) revealed ambiguous low-density areas in the bilateral globi pallidi. Further analysis by postmortem magnetic resonance (PMMR) imaging showed these lesions more clearly; the lesions appeared as marked high signal intensity areas on both the T2-weighted images and the fluid-attenuated inversion recovery sequences. A subsequent autopsy revealed signs of pneumonia, dehydration, starvation, and hypothermia, suggesting that the man died from prolonged CO poisoning. Both globi pallidi contained grossly ambiguous lesions, and a detailed neuropathologic investigation revealed these lesions to be coagulative necrotic areas; this finding was compatible with a diagnosis of prolonged CO poisoning. This case report shows that postmortem imaging, especially PMMR, is useful for detecting necrotic lesions associated with prolonged CO poisoning. This report further exemplifies the utility of PMMR for detecting brain lesions, which may be difficult to detect by macroscopic analysis.
... Although several postmortem studies have demonstrated the diagnostic potential of MRI in forensic neuroimaging [27][28][29][30][31], medico-legal societies still do not consider MRI a substitute for forensic autopsies and instead view MRI as a supplementary examination. Autopsy and CT are considered the gold standard in forensic investigations of craniocerebral gunshot wounds since these examination modalities usually provide information related to the most relevant forensic questions, while the diagnostic opportunities for MRI are frequently unknown. ...
... However, in cases of massive bone damage and soft tissue destruction together with a longer postmortem interval, identification of the wound tract can be challenging or infeasible on CT, while MRI can still provide information on the wound tract as observed in case 1 of the present study. Likewise, at autopsy, examinations of cerebral tissue in cases with a longer postmortem interval can also be challenging, while in situ assessments of the cerebral tissue and the detection of hemorrhages by MRI are feasible [27]. Postmortem MRI can delineate relevant soft tissue injuries that may be missed macroscopically at autopsy, such as shearing injuries [30,32], and the MRI examination can be reassessed for a second opinion at any time afterwards. ...
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Article
Compared to computed tomography (CT), magnetic resonance imaging (MRI) provides superior visualization of the soft tissue. Recently, the first 7 Tesla (7 T) MRI scanner was approved for clinical use, which will facilitate access to these ultra-high-field MRI scanners for noninvasive examinations and scientific studies on decedents. 7 T MRI has the potential to provide a higher signal-to-noise ratio (SNR), a characteristic that can be directly exploited to improve image quality and invest in attempts to increase resolution. Therefore, evaluating the diagnostic potential of 7 T MRI for forensic purposes, such as assessments of fatal gunshot wounds, was deemed essential. In this article, we present radiologic findings obtained for craniocerebral gunshot wounds in three decedents. The decedents were submitted to MRI examinations using a 7 T MRI scanner that has been approved for clinical use and a clinical 3 T MRI scanner for comparison. We focused on detecting tiny injuries beyond the wound tract caused by temporary cavitation, such as microbleeds. Additionally, 7 T T2-weighted MRI highlighted a dark (hypo intense) zone beyond the permanent wound tract, which was attributed to increased amounts of paramagnetic blood components in damaged tissue. Microbleeds were also detected adjacent to the wound tract in the white matter on 7 T MRI. Based on the findings of radiologic assessments, the advantages and disadvantages of postmortem 7 T MRI compared to 3 T MRI are discussed with regard to investigations of craniocerebral gunshot wounds as well as the potential role of 7 T MRI in the future of forensic science.
... In bodies with no signs of putrefaction the overall specificity for intra-and extra-axial brain findings, compared to autopsy, was reported as 94% for both PMCT (post mortem computed tomography) and PMMR (post mortem magnetic resonance) [9]. PMMR can identify brain morphology and pathological findings in softened or liquefied brains, even when they are not detectable in PMCT scan or at autopsy [10]. ...
... However, they are difficult to reliably interpret reconstructively. From a neuroradiological experience, subdural or subarachnoid hemorrhages are known to undergo repositioning or relocation either antemortem [15] when there is already a lesion of the dura because of previous trauma, or, possibly, postmortem [9]. This is even more so the case with increasing liquefaction of the brain over time due to postmortem decomposition. ...
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Article
This paper aims to demonstrate that post-mortem CT (PMCT) can locate intracranial hemorrhages, even in decomposed cases. This is of relevance in that post-mortem decomposition is particularly damaging to the brain tissue’s consistency, resulting in great difficulties to reliably diagnose and locate intracranial hemorrhages. We searched our case database of the last 11 years to find cases with decomposition of the body, where PMCT and an autopsy had been performed. We identified eleven cases according to these criteria. Postmortem interval ranged from 2 days to 2 weeks, and post-mortem radiological alteration index (RAI) was at or above 49. Eight out of eleven cases showed an intraparenchymal hemorrhage whereas the hemorrhage was extra-axial in the remaining three cases. Autopsy validated the presence of intracranial hemorrhage in all eleven cases, but location could not be confirmed due to liquid state of the brain. PMCT identified and localized intracranial hemorrhages in decomposed bodies, and in all of these cases, autopsy validated their presence. The actual cause of the hemorrhage (e.g. tumor, metastasis, vascular malformation, hypertensive hemorrhage) remained obscure. From this case series, it can be concluded that PMCT may add relevant information pertaining to localization of intracranial hemorrhages in decomposed bodies.
... Based on current knowledge, the signal changes caused by an intracranial bleed in a corpse are evaluated as if in living subjects, and further research must be performed [135,136]. Recent publications investigated PMCT and PMMR correlated with autopsy regarding postmortem forensic neuroimaging and yielded an overall specificity of 94% for intra-and extra-axial findings in PMCT and PMMR [137]. Furthermore, the lowest specificity was 70% in subarachnoid and ventricular hemorrhages [137]. ...
... Recent publications investigated PMCT and PMMR correlated with autopsy regarding postmortem forensic neuroimaging and yielded an overall specificity of 94% for intra-and extra-axial findings in PMCT and PMMR [137]. Furthermore, the lowest specificity was 70% in subarachnoid and ventricular hemorrhages [137]. Añon et al. stated that discrete extra-axial hemorrhages may escape on both PMCT and PMMR, particularly in the basilar or posterior fossa of the skull. ...
Chapter
Chapter 19: Postmortem and Forensic Magnetic Resonance Imaging SUMMARY: Magnetic resonance imaging (MRI) is a technique used in biomedical imaging and radiology to visualize internal structures of the body. Because MRI provides excellent contrast between different soft tissues, the technique is especially useful for diagnostic imaging of the brain, muscles, and heart. In the past 20 years, MRI technology has improved significantly with the introduction of systems up to 7 Tesla (7 T) and with the development of numerous post-processing algorithms such as diffusion tensor imaging (DTI), functional MRI (fMRI), and spectroscopic imaging. From these developments, the diagnostic potentialities of MRI have improved impressively with an exceptional spatial resolution and the possibility of analyzing the morphology and function of several kinds of pathology. Given these exciting developments, the Magnetic Resonance Imaging Handbook: Imaging of the Pelvis, Musculoskeletal System, and Special Applications to CAD is a timely addition to the growing body of literature in the field. Offering comprehensive coverage of cutting-edge imaging modalities, this book: Discusses MRI of the urinary system, pelvis, spine, soft tissues, lymphatics, and brain Explains how MRI can be used in fetal, pediatric, forensic, postmortem, and computer-aided diagnostic (CAD) applications Highlights each organ’s anatomy and pathological processes with high-quality images Examines the protocols and potentialities of advanced MRI scanners such as 7 T systems Includes extensive references at the end of each chapter to enhance further study Thus, the Magnetic Resonance Imaging Handbook: Imaging of the Pelvis, Musculoskeletal System, and Special Applications to CAD provides radiologists and imaging specialists with a valuable, state-of-the-art reference on MRI.
... Based on current knowledge, the signal changes caused by an intracranial bleed in a corpse are evaluated as if in living subjects, and further research must be performed [135,136]. Recent publications investigated PMCT and PMMR correlated with autopsy regarding postmortem forensic neuroimaging and yielded an overall specificity of 94% for intra-and extra-axial findings in PMCT and PMMR [137]. Furthermore, the lowest specificity was 70% in subarachnoid and ventricular hemorrhages [137]. ...
... Recent publications investigated PMCT and PMMR correlated with autopsy regarding postmortem forensic neuroimaging and yielded an overall specificity of 94% for intra-and extra-axial findings in PMCT and PMMR [137]. Furthermore, the lowest specificity was 70% in subarachnoid and ventricular hemorrhages [137]. Añon et al. stated that discrete extra-axial hemorrhages may escape on both PMCT and PMMR, particularly in the basilar or posterior fossa of the skull. ...
Full-text available
Chapter
Chapter 19: Postmortem and Forensic Magnetic Resonance Imaging SUMMARY: Magnetic resonance imaging (MRI) is a technique used in biomedical imaging and radiology to visualize internal structures of the body. Because MRI provides excellent contrast between different soft tissues, the technique is especially useful for diagnostic imaging of the brain, muscles, and heart. In the past 20 years, MRI technology has improved significantly with the introduction of systems up to 7 Tesla (7 T) and with the development of numerous post-processing algorithms such as diffusion tensor imaging (DTI), functional MRI (fMRI), and spectroscopic imaging. From these developments, the diagnostic potentialities of MRI have improved impressively with an exceptional spatial resolution and the possibility of analyzing the morphology and function of several kinds of pathology. Given these exciting developments, the Magnetic Resonance Imaging Handbook: Imaging of the Pelvis, Musculoskeletal System, and Special Applications to CAD is a timely addition to the growing body of literature in the field. Offering comprehensive coverage of cutting-edge imaging modalities, this book: Discusses MRI of the urinary system, pelvis, spine, soft tissues, lymphatics, and brain Explains how MRI can be used in fetal, pediatric, forensic, postmortem, and computer-aided diagnostic (CAD) applications Highlights each organ’s anatomy and pathological processes with high-quality images Examines the protocols and potentialities of advanced MRI scanners such as 7 T systems Includes extensive references at the end of each chapter to enhance further study Thus, the Magnetic Resonance Imaging Handbook: Imaging of the Pelvis, Musculoskeletal System, and Special Applications to CAD provides radiologists and imaging specialists with a valuable, state-of-the-art reference on MRI.
... The increased application of postmortem cross-sectional imaging in forensic pathology has gradually evolved over the last two decades and resulted in researchers exploring the suitability of postmortem computed tomography (CT) and magnetic resonance imaging to establish the cause of death [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] without autopsy. There is variable agreement between postmortem CT and autopsy findings [18]. ...
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Background Postmortem computed tomography (CT) and magnetic resonance imaging have been gradually introduced to forensic pathology centres over the past two decades, with varying results in comparison to autopsy. Objective The purpose of this study was to determine the accuracy of postmortem CT in determining a cause of death in children who died of unnatural causes. Materials and methods This was a prospective recruitment of 30 children (< 18 years) who underwent postmortem CT and a forensic autopsy. A cause of death was independently assigned by two experienced paediatric radiologists and compared to that of the forensic autopsy. Results A correct cause of death was assigned by reviewers 1 and 2 in 70% (n = 21/30) and 67% (n = 20/30) of cases, respectively. For gunshot injuries and blunt force head injuries, there was 91% (n = 10/11) and 100% (n = 6/6) agreement between forensic autopsy and both reviewers, respectively. No cause of death could be assigned by reviewers 1 and 2 in 27% (n = 8) and 30% (n = 9) of cases, respectively. An incorrect cause of death was assigned by both reviewers in one case (3%). The Cohen Kappa level of agreement between the forensic autopsy and reviewers 1 and 2 was k = 0.624 (95% confidence interval [CI]: 0.45–0.80, P = 0) and k = 0.582 (95% CI 0.41–0.76, P = 0), respectively. There was near perfect agreement between reviewers 1 and 2 (k = 0.905) (95% CI 0.78–1.00, P = 0). Conclusion Postmortem CT has good diagnostic accuracy for identifying a cause of death related to trauma, but it has poor accuracy for children dying from causes not associated with apparent physical injury.
... However, PMMRI remains an extremely useful and sensitive technique for the study of soft tissues, as in cases characterized by the presence of intra-and extra-cranial hemorrhages, bruises, abrasions and lacerations of the scalp [60], axonal damage and alterations in the relationship between gray matter and white matter [61]. On the basis of a famous pilot study [62], in fact, subsequent studies have shown how this technique allows to appreciate with high sensitivity (100%) and specificity (98-100%) signs attributable to bleeding lesions [63][64][65] as well as suffering neuronal ischemic. ...
Article
Background: Traumatic brain injury (TBI) during birth constitutes one of the most relevant causes of mortality and morbidity in newborns worldwide. Although improvements in obstetrical management and better indications for caesarean section have led to a consistent decrease in the incidence of perinatal mechanical injury, vacuum extraction is still associated with a high complications rate leading to several forensic issues in the evaluation of healthcare professional management. Methods: Vacuum-associated lesions may be topographically distinguished as extracranial or intracranial injuries. In order to achieve a correct assessment, diagnostic procedure should include post-mortem computed tomography and magnetic resonance imaging, autopsy examination, brain sampling and histological/immunohistochemical examination. Results: Post-mortem imaging represents a valid aid to guarantee preliminary evidence and direct subsequent investigations. An appropriate autopsy sampling must include several areas of cortex and underlying white matter; moreover, any visceral hemorrhages or other lesions should be sampled for the histological and immunohistochemical assessment of vitality and timing. Conclusions: This study aimed to promote a validated step-by-step procedure to be adopted in order to standardize and to make easier the post-mortem framing and timing of vacuum-associated pediatric brain injuries.
... The amount and quality of information that can be obtained from a second autopsy are greatly reduced, while multiple autopsies yield only scant information. [10] In addition, this invasive approach may be emotionally unacceptable to the family members of some victims or may conflict with the beliefs of certain religions (e.g., traditional Islam and Judaism). Virtopsy, as a noninvasive or minimally invasive method of cadaver examination, involves the use of imaging technologies to digitally examine and record fractures, internal foreign bodies, and other injuries in the cadaver. ...
Article
This review summarizes the mode of application of virtual anatomy technology in the construction of a police system. Local public security organizations have explored the application modes of virtual anatomy construction, such as the multiparty co-construction mode, cooperation mode, and individual construction mode, and reviewed (1) the understanding of public security and application process of virtual anatomy; (2) the problems faced in the construction and application processes, such as those associated with support of human resources, equipment supplies and financial expenditure, the limitations of the technology itself, legal issues with application, shrinkage of the identification business, and appraiser-related problems; and (3) the prospect of application of virtopsy in public security systems.
... Yen et al. [14] performed CT and MRI scans on 57 cadavers and evaluated the value of virtopsy in cranial autopsy. They demonstrated that the results of virtopsy were comparable to those of conventional autopsy. ...
Article
Virtopsy employs computed tomography and magnetic resonance imaging, which are commonly used in clinical medicine, to determine the cause and manner of death. Virtopsy is a multidisciplinary technique that combines forensic medicine, pathology, radiology, computer graphics, biomechanics, and physics. Virtopsy is rapidly gaining importance in forensic science and has been extensively studied in several areas of forensic pathology. In this study, we reviewed domestic and international research on causes of death, traffic injuries, medical disputes, gunshot trauma, postmortem changes, and inference of time of death to discuss with colleagues the role of virtopsy in forensic pathology.
... Therefore, measurements can be performed repeatedly, and could possibly reduce intraobserver and interobserver measurement errors compared with measurements of real eschweizerbart_xxx ASIS-IS: distance from the anterosuperior iliac spine to the most posterior point of the ischial spine, ASIS-IT: distance from the anterosuperior iliac spine to the most posterior point of the ischial tuberosity, SD: standard deviation (Karakas et al. 2011). The use of virtual skeletons has recently become widespread in the fields of forensic medicine, anthropology, and anthropometry (Dedouit et al. 2007;Yen et al. 2007;Grabherr et al. 2009). Another advantage of our study is that our estimation formulas were derived from measurements of living stature. ...
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Article
Introduction: A major challenge in anthropology is the estimation of human stature based on human bones since the stature of cadavers is slightly different from that of living humans. This study aimed to investigate the feasibility of estimating living stature in Japanese subjects based on sacral and coccygeal lengths as measured on three-dimensional (3D) models of the femur and pelvis reconstructed from cross-sectional computed tomography (CT) images. Subjects and methods: For this cross-sectional study, 106 healthy Japanese subjects (54 men and 52 women) were recruited. We measured the distances from the anterosuperior iliac spine (ASIS) to the most posterior point of the ischial spine (IS) (ASIS-IS), and from the ASIS to the most inferior point of the ischial tuberosity (IT) (ASIS-IT) on 3D bone models reconstructed from multi-slice CT images. Correlations of living stature with ASIS-IS and/or ASIS-IT on the left and right sides of the pelvis were evaluated. Multiple regression equations were derived and used as formulas for living stature estimation. Results: In men, living stature had strong correlations with ASIS-IS + ASIS-IT on both the left and right sides; Pearson's correlation coefficients were 0.717 and 0.706, respectively. In contrast, in women, living stature showed stronger correlations with all of the studied parameters; Pearson's correlation coefficients were highest for ASIS-IS + ASIS-IT on both the left and right sides (r = 0.753 and 0.744, respectively) compared with those in men. Formulas based on ASIS-IS + ASIS-IT provided the best estimation in both men and women, while ASIS-IS alone demonstrated a better estimation than ASIS-IT on both the left and right sides. Conclusions: This study revealed that ASIS-IS and ASIS-IT measured from CT images were reliable predictors of living stature in the Japanese population. Our estimation formulas were derived from measurements of living stature that were not affected by the physiological changes observed in cadavers. To the best of our knowledge, this is the first study to derive estimation formulas based on living stature. Our method may be useful in the identification of disaster victims, wherein long bones are usually not found intact but pelvic bones are. Furthermore, the findings could be relevant to the field of anthropology for estimating living stature.
... These methods are expensive (AFIS costs can run in the millions of dollars depending on the agencies participating and the complexity of the system [2]) and time-consuming (weeks for DNA test from bone). However, their main drawback most reports that exist on PM MRI are generally based on small case samples [14]. Second, even if PM CT and MRI have proven to be useful diagnostic tools in forensic medicine, some studies remark that CT is superior to MRI in the visualization of osseous and ligamentous injuries after trauma [15]. ...
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Article
This paper represents the first survey on the application of AI techniques for the analysis of biomedical images with forensic human identification purposes. Human identification is of great relevance in today’s society and, in particular, in medico-legal contexts. As consequence, all technological advances that are introduced in this field can contribute to the increasing necessity for accurate and robust tools that allow for establishing and verifying human identity. We first describe the importance and applicability of forensic anthropology in many identification scenarios. Later, we present the main trends related to the application of computer vision, machine learning and soft computing techniques to the estimation of the biological profile, the identification through comparative radiography and craniofacial superimposition, traumatism and pathology analysis, as well as facial reconstruction. The potentialities and limitations of the employed approaches are described, and we conclude with a discussion about methodological issues and future research.
... Magnetic Resonance Imaging (MRI) has been recently applied in post-mortem examinations for detection of injuries of brain, chest, abdomen, heart and joints (33)(34)(35). Recently, a significant raise has been occurred in application of MRI in post-mortem examinations, and postmortem MRI has been developed technically besides the developments of clinical MRI (36-38) because the sensitivity and power of post-mortem MRI is the same as the clinical MRI (39). ...
... In the medicolegal investigation of fatal hanging, the detection of hemorrhages and soft tissue emphysema are particularly important, proving vitality during the incident [12][13][14][15][16]. Therefore, magnetic resonance imaging (MRI) has been proposed for cases of hanging due to its superior soft tissue visualization compared to CT or X-ray [9,10]. In particular, intramuscular and lymph node hemorrhages or swellings can be visualized by MRI [17,18]. However, other traumatic alterations, such as osseous lesions, are hardly visible on MRI. ...
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Article
The purpose of this study was to evaluate the added value of postmortem magnetic resonance imaging (MRI) compared to postmortem computed tomography (CT) and autopsy in cases of fatal hanging. In addition, the study analyzed the strengths of each examination method regarding typical injuries in these cases. We investigated a cohort of 25 decedents who underwent CT, MRI and autopsy. Two radiologists assessed all MR images of the head and neck as well as the corresponding CT images. The results were compared to autopsy findings by retrospectively analyzing the autopsy reports. Postmortem MRI revealed intramuscular hemorrhages in a large number of cases, however, autopsy did not confirm all of the detected hemorrhages. CT and autopsy detected fractures in several cases, whereas MRI showed a fracture in just one single case. Other previously described vital signs and relevant findings, such as fracture-related gas bubbles, soft tissue emphysema or pneumomediastinum, were observed in only a few individual cases. MRI provided added diagnostic value in the detection of soft tissue injuries and lymph node swelling in fatal hangings. As an adjunct to autopsy, postmortem MRI may reveal additional hemorrhages, which might be missed at autopsy. Since standard MRI demonstrated low sensitivity for the detection of fractures, an additional imaging modality or autopsy is required to overcome this limitation.
... Furthermore, autopsy is a highly destructive operation with poor repeatability. The amount and quality of information provided by secondary anatomy will be greatly reduced after an autopsy is performed, and there is minimal gain from multiple autopsy sessions [36]. Imaging techniques such as X-ray, MSCT, and MRI provide noninvasive examinations, replacing scalpels with instruments such as surface scans, X-rays, and magnetic resonance and replacing autopsy records (written in an understandable regulatory language) with objective images. ...
Article
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.
... Therefore, measurements can be performed repeatedly, possibly reducing intraobserver and interobserver errors (Karakas et al. 2011). The use of virtual skeletons has recently become widespread in forensic medicine, anthropology, and anthropometry (Dedouit et al. 2007;Yen et al. 2007;Grabherr et al. 2009). Second, our estimation formulae were derived based on living stature. ...
Full-text available
Article
We investigated the feasibility of estimating living stature in Japanese subjects using femoral length and pelvic dimensions measured on three-dimensional (3D) pelvic models reconstructed from cross-sectional computed tomography (CT) images. For this cross-sectional study, we recruited 106 healthy Japanese subjects. Maximum and bicondylar femoral length, as well as pelvic width, depth, and height, were measured on 3D bone models reconstructed from multi-slice CT images. The correlation of stature with each parameter was evaluated, and multiple regression equations were derived as formulae for living stature estimation. Prediction accuracy was evaluated as the mean absolute difference (MAD) between the measured and estimated statures. Maximum and bicondylar femoral lengths were similar and showed strong correlations with stature (> 0.8 in both males and females). Among the pelvic dimensions, height (craniocaudal length) showed the strongest correlation with stature in both males (r = 0.649) and females (r = 0.684). Formulae using femoral length plus pelvic height provided the best estimation of living stature in both males and females (MAD, 25-26 mm). Among the studied pelvic dimensions, height provided the best estimation of living stature when used alone (MAD, 34-36 mm) in both males and females. The intraclass correlation coefficients were high (> 0.9) for both intraobserver and interobserver reliability. Femoral length and pelvic height measured on CT images are reliable predictors of living stature in the Japanese population. Such tools are particularly useful in disaster victim identification, when the long bones are often not intact but the pelvic bones are.
... The Dictionary of Legal Medicine proposed by Manif and Elias Zacharias, 10 says that the implementation of autopsy includes examination of the body, externally i.e on the surface and internally i.e body cavities, taking into consideration that the main goal to diagnose is thanatology. [11][12][13] The traditional internal autopsy procedure consists of body mutilating techniques; but, the major objection against autopsies are the emotional aspects of the victim's relatives. 12 Yet the need to know the cause of death and to rule out any unnatural cause as well as any criminal angle or to find the identity of the deceased individual overrules any emotional involvement. ...
... 4,[7][8][9][10][11] The ex vivo brain is also useful in forensic neurology research. 12 Several previous MRI studies have measured physical values, 13 such as relaxation and diffusion values, that reflect tissue conditions for in vivo tissue assessment. Experiments to measure these values and compare them between in vivo and ex vivo brains have been conducted using the brains of mice, macaques, and humans. ...
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Article
Purpose: Ex vivo brains have different MRI properties than in vivo brains because of chemical changes caused by fixative solutions, which change the signal intensity and/or tissue contrast on MR images. In this study, we investigated and compared the MRI properties of in vivo and ex vivo brains. Methods: Using a Bruker 9.4T experimental scanner unit for animals (Biospin GmbH, Ettlingen, Germany), we performed this study on the common marmoset. We measured the relaxation and diffusion values in the white matter and cortex of common marmosets and compared these values between in vivo brains (n = 20) and ex vivo brains (n = 20). Additionally, we observed the relationship between the tissue fixation duration and MRI properties by imaging a brain that underwent long-term fixation in a preliminary examination (n = 1). Results: The T1 values of ex vivo brains were decreased compared with those of in vivo brains; however, there were no significant difference in the T2 and T2* values of in vivo and ex vivo brains. Axial, radial, and mean diffusivity values of ex vivo brains decreased to approximately 65% and 52% of those of in vivo brains in the cortex and white matter, respectively. Conversely, fractional anisotropy values were not significantly different between in vivo and ex vivo brains. Conclusion: The T1 values and diffusion coefficient values of the ex vivo brains were strikingly different than those of the in vivo brains. Conversely, there were no significant changes in the T2, T2* or fractional anisotropy values. Altogether, the dehydration caused by tissue fixation and the reduction in brain temperature were involved in changing the relaxation and diffusion coefficient values. Here, it was difficult to specify all factors causing these changes. Further detailed study is needed to examine changes in MRI properties.
... After reviewing the abstracts, 115 articles were excluded, as neither postmortem CT nor postmortem MRI was performed. From the remaining articles, three articles [10][11][12] had to be excluded, as the findings could not be solely assigned to strangulation-related deaths. Additionally, three articles had to be excluded as CT [13] or microfocus CT (μCT) [14,15] was performed on removed tissue. ...
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Article
Several articles have described the use of postmortem computed tomography (CT) and postmortem magnetic resonance imaging (MRI) in forensic medicine. Although access to CT scanners and, particularly, access to MRI scanners, is still limited for several institutes, both modalities are being applied with increasing frequency in the forensic setting. Certainly, postmortem imaging can provide crucial information prior to autopsy, and this method has even been considered a replacement to autopsy in selected cases by some forensic institutes. However, the role of postmortem imaging has to be assessed individually according to various injury categories and causes of death. Therefore, this systematic review focuses on the role of postmortem CT and MRI in cases of hanging and ligature and manual strangulation. We assessed the most common and relevant findings on CT and MRI in cases of strangulation and compared the detectability of these findings among CT, MRI and autopsy. According to the available literature, mainly fractures of the hyoid bone or thyroid cartilage were investigated using postmortem CT. Compared to autopsy, CT demonstrated equivalent results concerning the detection of these fractures. A currently described “gas bubble sign” may even facilitate the detection of laryngeal fractures on CT. Regarding the detection of hemorrhages in the soft tissue of the neck, postmortem MRI is more suitable for the detection of this “vital sign” in strangulation. Compared to autopsy, postmortem MRI is almost equally accurate for the detection of hemorrhages in the neck. Another “vital sign”, gas within the soft tissue in hanging, which is hardly detectable by conventional autopsy, can be clearly depicted by CT and MRI. The number of cases of manual and ligature strangulation that were investigated by means of postmortem CT and MRI is much smaller than the number of cases of hanging that were investigated by CT and MRI. Likewise, judicial hanging and the hangman’s fracture on postmortem imaging were described in only a few cases. Based on the results of this systematic review, we discuss the additional value of CT and MRI in fatal strangulation compared to autopsy, and we reflect on where the literature is currently lacking.
... Hospital autopsy rates in the UK have fallen significantly [15] prompting a search for nonor minimally invasive examination strategies [16], and forensic radiology is a rapidly growing subspecialty [17]. However, major discrepancies in causes of death identified by consensus radiology reads of post-mortem MRI compared to autopsy occur in 43% of cases (95% CI 36-50%) [17], and post-mortem neuroimaging in 57 unselected cases demonstrated sensitivities ranging from 0 to 100% for the detection of relevant post-mortem findings [18]. ...
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Article
The relationship between magnetic resonance imaging (MRI) and clinical variables in patients suspected to have Creutzfeldt-Jakob Disease (CJD) is uncertain. We aimed to determine which MRI features of CJD (positive or negative), previously described in vivo, accurately identify CJD, are most reliably detected, vary with disease duration, and whether combined clinical and imaging features increase diagnostic accuracy for CJD. Prospective patients suspected of having CJD were referred to the National CJD Research and Surveillance Unit between 1994–2004; post-mortem, brains were sent for MRI and histopathology. Two neuroradiologists independently assessed MRI for atrophy, white matter hyperintensities, and caudate, lentiform and pulvinar signals, blind to histopathological diagnosis and clinical details. We examined differences in variable frequencies using Fisher’s exact tests, and associations between variables and CJD in logistic regression models. Amongst 200 cases, 118 (59%) with a histopathological diagnosis of CJD and 82 (41%) with histopathological diagnoses other than CJD, a logistic regression model including age, disease duration at death, atrophy, white matter hyperintensities, bright or possibly bright caudate, and present pulvinar sign correctly classified 81% of cases as CJD versus not CJD. Pulvinar sign alone was not independently associated with an increased likelihood of histopathologically-confirmed CJD (of any subtype) or sporadic CJD after adjustment for age at death, disease duration, atrophy, white matter hyperintensities or caudate signal; despite the large sample, data sparsity precluded investigation of the association of pulvinar sign with variant CJD. No imaging feature varied significantly with disease duration. Of the positive CJD signs, neuroradiologists most frequently agreed on the presence or absence of atrophy (agreements in 169/200 cases [84.5%]). Combining patient age, and disease duration, with absence of atrophy and white matter hyperintensities and presence of increased caudate signal and pulvinar sign predicts CJD with good accuracy. Autopsy remains essential.
... However, PMMR offers far better soft tissue contrast than PMCT and therefore acts as a method that is complementary to PMCT, particularly for cases of, for example, cardiac death and cerebral pathology. [14][15][16][17][18] Swelling of the brain is a typical and normal finding on postmortem images and may incorrectly elicit interpretations of antemortem agonal cerebral edema as pathological. 4,[19][20][21][22] Therefore, the detection of antemortem or agonal cerebral edema despite normal postmortem alterations, such as brain swelling, remains difficult based on imaging, fairly subjective, and based on the reader's experience. ...
Article
The purpose of this study was to investigate papilledema (PA) as a diagnostic criterion for the presence of antemortem or agonal cerebral edema despite normal postmortem brain swelling on postmortem magnetic resonance imaging (PMMR) in comparison with conventional autopsy.One hundred subjects with head PMMR and autopsy were included in this study. The sensitivities, specificities, positive predictive values (PPVs), negative predictive values (NPVs), and accuracies were calculated in terms of the PA, PMMR, and cerebral edema on autopsy. Spearman r tests were used to analyze the linear correlations of PA and the radiological and autoptic determination of cerebral edema.In autopsy, the sensitivity regarding the presence of PA and cerebral edema was 66.2% (PPV, 70.5%), and specificity was 48.6% (NPV, 28.3%), with an overall accuracy of 60%. On PMMR, the sensitivity was 86.6% (PPV, 95%). The specificity was 90.9% (NPV, 34%), with an overall accuracy of 88%. The Spearman correlation revealed a statistically significant result (P < 0.001), which indicated a strong linear correlation of the presence of PA and cerebral edema with the autopsy results and the PMMR results. The presence of PA may aid in the diagnoses of cerebral edema despite normal postmortem brain swelling based on PMMR.
Article
The fluid attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) sequence aims at suppressing the signal of the cerebrospinal fluid (CSF) by acquiring images at the time point at which the longitudinal magnetization and therefore the signal of CSF is zero. This time point is also called the null point inversion time (TInull). However, the FLAIR sequence is impaired by the temperature dependency of TInull in post mortem MRI due to the lower body temperature of the deceased subject. Therefore, the temperature correction of TInull is crucial for correctly suppressing the CSF signal in post mortem FLAIR imaging. Thus, the goal of this study was to determine the temperature effect on post mortem TInull for achieving a robust suppression of the CSF signal in in situ post mortem MRI using the FLAIR sequence. For this purpose, nine deceased subjects underwent an in situ MRI brain examination on a 3 T MRI scanner. TInull of CSF was determined quantitatively based on different FLAIR acquisitions using varying inversion times. The brain and rectal temperatures were determined prior to the MRI scan. A significant positive linear relation was found between TInull of CSF and the brain temperature, as well as between TInull of CSF and the rectal temperature. The found linear relations between TInull and both brain and rectal temperatures allow correcting TInull for varying temperatures of the deceased. This in turn enables an optimal suppression of the CSF signal in future post mortem FLAIR MRI acquisitions.
Chapter
Forensic imaging is often represented as a new field emerging from multidisciplinary work and research in forensic medicine and radiology. However, looking back on the interaction between radiology and forensic medicine, it has to be stated that radiology has always been used also for forensic purposes. This collaboration is therefore nearly as old as radiology itself. The year 1895 is important for radiologists because it was the year of the realization of the first radiography by Wilhelm Conrad Röntgen (Brogdon 1964). In fact, the benefit of radiographs to reveal the body’s hidden secrets started to be practically used in 1895 in the United States of America, and then in 1896 in England (Brogdon 1998). These first forensic radiographs were used for clinical and postmortem purposes. Very early, the possibility of localizing gunshot projectiles on X-ray images was highlighted. These are important facts, because they perfectly illustrate the early interaction between two different medical specialities: Radiology and Forensic Pathology. Interestingly, things are not so different today: Radiology assists clinical forensic medicine as well as forensic pathology. However, one major difference compared to those early experiences is of course that the radiological tools available today have advanced greatly. Those tools permit to document the inside of a human body and to digitalize it in a highly detailed matter. In postmortem cases, the investigation of those digitalized bodies is often called “virtual autopsy” (Thali et al. 2003) and used as complementary tool to conventional forensic autopsy.
Chapter
There are huge differences between interpretating radiological images from a forensic point of view versus a clinical point of view. Additionally, in post-mortem imaging post-mortem changes and typical signs have to be kept in mind and recognized on the images for correct interpretation.The differences between clinical and forensic radiology as well as topics one radiologist can learn from the other are discussed in this chapter.
Article
Quantitative post-mortem magnetic resonance imaging (PMMR) allows for measurement of T1 and T2 relaxation times and proton density (PD) of brain tissue. Quantitative PMMR values may be used for advanced post-mortem neuro-imaging diagnostics such as computer aided diagnosis. So far, the quantitative T1, T2 and PD post-mortem values of regular anatomical brain structures were unknown for a 3 Tesla PMMR application. The goal of this basic research study was to evaluate the quantitative values of post-mortem brain structures for a 3 T post-mortem magnetic resonance application with regard to various corpse temperatures. In 50 forensic cases, a quantitative PMMR brain sequence was applied prior to autopsy. Measurements of T1 (in ms), T2 (in ms), and PD (in %) values of cerebrum (Group 1: frontal grey matter, frontal white matter, thalamus, caudate nucleus, globus pallidus, putamen, internal capsule) brainstem and cerebellum (Group 2: cerebral peduncle, substantia nigra, red nucleus, pons, middle cerebellar peduncle, cerebellar hemisphere, medulla oblongata) were conducted in synthetically calculated axial PMMR brain images. Assessed quantitative values were corrected for corpse temperature. Temperature dependence was observed mainly for T1 values. ANOVA testing resulted in significant differences of quantitative values between the investigated anatomical brain structures in both groups. It can be concluded that temperature corrected 3 Tesla PMMR T1, T2 and PD values are feasible for characterization and discrimination of regular anatomical brain structures. This may provide a base for future advanced diagnostics of forensically relevant brain lesions and pathology.
Chapter
Imaging techniques (plain radiographs, multi slice computed tomography (MSCT), and magnetic resonance (MRI)) are being increasingly implemented in forensic pathology. These methods may serve as an adjuvant to classic forensic medical diagnosis and as support to forensic autopsies. It is well noted that various post-processing techniques can provide strong forensic evidence for use in legal proceedings. This chapter reviews vertebral morphometry application in forensic, expressly used in the case of semi-automatic digital recognition of vertebral heights in fractures, by means of vertebral shape analysis which relies on six or more points positioned over the margins of each vertebrae T5 to L4 used to calculate anterior, medial, and posterior heights and statistical shape models. This approach is quantitative, more reproducible, and more feasible for large-scale data analysis, as in drug trials, where assessment may be performed by a variety of clinicians with different levels of experience. As a result, a number of morphometric methodologies for characterisation of osteoporosis have been developed. Current morphometric methodologies have the drawback of relying upon manual annotations. The manual placement of morphometric points on the vertebrae is time consuming, requiring more than 10 min per radiograph and can be quite subjective. Several semi-automated software have been produced to overcome this problem, but they are mainly applicable to dual X-ray absorptiometry (DXA) scans. Furthermore, this chapter aims to verify by an experimental model if the technique could contribute, in present or in future, to investigate the modality of traumatic vertebral injuries which may explain the manner of death.
Article
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.
Chapter
The importance of brain postmortem imaging is roughly twofold. Firstly, brain postmortem imaging can assist autopsy in cause of death determination, in personal identification, and in various other forensic tasks. By knowing brain information in advance, pathologists and assistants who would perform irreversible and destructive investigations of the head of cadavers could prepare to search for the lesions suggested by imaging prior to the autopsy. Secondly, postmortem imaging is useful for “triage” of autopsies. In the cranium, there are many fatal lesions and injuries that can be evaluated using postmortem imaging, which has the potential to reduce unnecessary autopsies. At the same time, since postmortem imaging cannot be a perfect substitute for autopsies, there are various pitfalls and limitations for investigating the cause of death based on postmortem imaging. In this chapter, we introduce the main points of postmortem imaging of the brain in the context of these two points. We also describe our recommended protocol and the basic postmortem changes observed in CT to facilitate an accurate understanding of the imaging findings.
Chapter
Investigation of Sudden Infant Death Syndrome - edited by Marta C. Cohen June 2019
Article
Background: Autopsies are considered an important quality assurance instrument in medicine, yet autopsy rates in many countries have been declining for many years. The proper role of the post-mortem examination in modern medicine is a matter deserving of study. Methods: This review is based on a selective search of the literature for publications on the role of autopsies as a quality assurance instrument. Results: Multiple studies have revealed substantial rates of discrepancy between pre- and post-mortem diagnoses, with reported rates lying in the range of 10% to 40%. The frequen- cy of so-called Goldman I erroneous diagnoses, i.e., those that are determined at autopsy and might have influenced the patient's survival, ranges from 2.4% to 10.7%. It can be as- sumed that the rate of serious diagnostic errors revealed by autopsy would fall if autopsy rates were to rise. Independently of the above-mentioned studies, a large-scale study of data from the period 1988-2008 revealed a decline in the rate of Goldman I erroneous diagnoses by more than half. The qualitative effects of autopsies, however, are difficult to measure. At present, imaging studies and minimally invasive or endoscopic diagnostic procedures can be performed post mortem as well, but the available studies show that these methods do not yet suffice to enable a coherent pathogenetic classification of disease processes. Conclusion: Autopsies should still be performed in the interest of quality assurance in medicine. Uniform standards in the performance and reporting of autopsies could lead to im- provement in the use of the data acquired through them.
Article
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.
Article
Cerebral venous thrombosis is a rare condition which constitutes 0.5% to 2% of all types of stroke and carries a mortality of up to 20% to 50%. It leads to cerebral edema, infarction, hemorrhage and venous hypertension. Clinically the diagnosis is confirmed using enhanced computed tomography (CT) angiography which demonstrates an empty delta sign in cerebral veins, particularly in the superior sagittal sinus. However, postmortem CT (PMCT) findings on cerebral venous thrombosis have not been documented in the literature. We present a case report of a 69-year-old man who on unenhanced PMCT scan showed an empty delta sign in the cerebral veins. The empty delta sign was able to be demonstrated in unenhanced PMCT which can be explained by hyper attenuation of the dural veins at postmortem forming an internal contrast highlighting the thrombus.
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For autopsies, in addition to classical non-enhanced post-mortem computed tomographies, (PMCT), an innovative technique consists in post-mortem vascular opacification. It is called post-mortem computed tomography angiography (PMCTA) and the most widespread method is multiphase PMCTA (MPMCTA). It permits the diagnosis and characterization of vascular lesions. Another radiological technique is the post-mortem magnetic resonance imaging (PMMR). Its great advantage is the optimal spontaneous inter-tissular contrast. The development of PMMR angiography (PMMRA) seems to be promising for post-mortem cardio-vascular explorations. 3D surface scanning combined with photogrammetry permits the documentation of information such as texture and colour, which may be combined with PMCT reconstructions, the surface scanning of objects or the environment of a deceased person, to perform virtual reconstitutions of the events. In forensic anthropology, PMCT is also very useful for identification purposes (comparative, reconstructive and lesional identification).
Chapter
Forensic medicine has always used radiographic techniques, and interested readers may also want to consult the “Autopsy and Histological Findings” chapter for more about the post-mortem context. For over a decade now, forensic medicine has been taking advantage of the new cross-sectional imaging modalities (ultrasound and especially CT and MRI). In virtual autopsy, one or more of these imaging techniques is performed prior to autopsy to prepare, guide, and facilitate the work of medical examiners in determining the cause of death. Post-mortem imaging is playing an increasingly important role, particularly in the field of suspected or confirmed abuse. However, familiarity with normal post-mortem changes on imaging—which can be diagnostically misleading—is essential.
Article
Introduction Post-mortem computed tomography (PMCT) and post-mortem magnetic resonance imaging (PMMR) are frequently used as an addition to autopsy. However, there is no research that determined the diagnostic value of these imaging techniques in forensic cases. The aim of this review is to evaluate the available literature with regard to the correlation between autopsy and imaging findings in the forensic investigation of gunshot victims to arrive at an the diagnostic value of PMCT and PMMR. Materials & methods The review process was set out as a systematic review according to the Cochrane guidelines. A systematic search was performed in MEDLINE and EMBASE to identify studies comparing autopsy and imaging techniques after fatal gunshot incidents. Autopsy and imaging techniques were compared for forensically relevant items: entrance wounds, exit wounds, trajectory of the bullet through the body, detection of metal fragments and identification of relevant injuries. The autopsy was the reference standard in all studies. Results In each study a minimum of one and a maximum of five items could be compared between the imaging techniques and the autopsy. In total seven studies complied with the inclusion criteria. The overall quality and level of detail of these studies did not allow for a formal meta-analysis. For the detection of the entrance wound five studies provide data and the correlation between imaging and autopsy was 100% in four studies, and 69.2% in one study. Five studies provide data on the exit wound and there was a 100% correlation in four, and 52.2% in one study. Six studies provide data on the bullet path and the correlation between techniques and autopsy was 100% in four studies and respectively 72.1% and 80% in the other two studies. For the detection of metal fragments three studies provide data and all these studies showed a 100% correlation between imaging and autopsy. Two studies provide data on detecting injuries with a correlation between imaging and autopsy of 100% and 87.2% respectively. Conclusion Despite the concerns on the quality of the reviewed studies, the literature shows that PMMCT has a high sensitivity in identifying the main forensic items in gunshot victims compared to the standard of reference; an autopsy. Forensic radiology and autopsy can be complementary in a forensic medical investigation.
Article
Background & Purpose: The diagnosis of the causes of sudden death using autopsy imaging has been in practice for many years. However, there are a few reports on autopsy imaging mainly focused on the stroke death. Postmortem CT scan as autopsy imaging in the emergency department reveals the trend in the causes of sudden death and the percentage of the stroke death in our autopsy imaging series. Methods: Postmortem CT scans from the head to the pelvis was conducted in 547 deceased cases between 2012 and 2014. Of them, the police requested postmortem CT scan for 246 cases. Among 337 patients taken by an ambulance as a cardiopulmonary arrest in our emergency department, 301 cases (89%) were conducted postmortem CT scan. Results: In the 547 autopsy-imaging series, 98 cases (18%) were diagnosed with internal death due to the several causes and 112 (20%) were external death. In the other 337 cases (62%), the cause of death could not be detected using postmortem CT scan. Twenty-nine cases (5%) were diagnosed with death from the stroke. Of them, 15 cases were diagnosed with subarachnoid hemorrhage, 13 were intracranial hemorrhage (4, pontine hemorrhage; 3, thalamo-putaminal hemorrhage; 3, subcortical hemorrhage; 1, putaminal hemorrhage; 1, cerebellar hemorrhage; 1, intraventricular hemorrhage), and only one case was diagnosed with large cerebral infarction due to occlusion of the internal cerebral artery. Conclusion: The frequency of stroke death was only 5% in 547 autopsy-imaging series using postmortem CT scan.
Article
The aim of the present study is to offer our experience concerning post-mortem magnetic resonance (PMMR) in foetal death cases and an evaluation of the differences between the findings acquired by PMMR and by forensic autopsy. Fifteen foetuses were recruited from July 2014 to December 2015. These had suffered intrauterine death in women in the 21st to 38th week of gestation who were treated in the emergency department for non-perception of foetal movements. We performed a PMMR on foetuses, 3 ± 1 days on average from the time of death, and then a complete forensic autopsy was performed. All 15 foetuses were examined with a whole-body study protocol, starting from the skull, down to and including the lower limbs. The total time of examination ranged from 20 to 30 min in each case. The external evaluation and description of post-mortem phenomena (maceration), record of the weight and detection and the various measurements of foetal diameters were evaluated before performing autopsy. A complete histopathological study was performed in each case. Out of 15 cases examined, eight were negative for structural anatomical abnormalities and/or diseases, both in the preliminary radiological examination and the traditional autopsy. In the remaining seven cases, pathological findings were detected by PMMR with corresponding results at autopsy. PMMR can provide useful information on foetal medical conditions and result in improved diagnostic classification. It may enable the planning of a more suitable technique before proceeding to autopsy, including focusing on certain aspects of organ pathology otherwise not detectable. The association between PMMR, post-mortem examination and related histological study of the foetus-placenta unit could help reduce the percentage of cases in which the cause of foetal death remains unexplained. Lastly, it may allow a selective sampling of the organ in order to target histological investigations.
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Introduction: Determination of post-traumatic interval remains one of the foremost important goals of any forensic investigation related to human crimes. The estimation of time since injury in cases of subdural haemorrhage has been studied only by a few investigators on the histological and radiological front. Aim: The purpose of this study was to determine the posttraumatic interval of Subdural Haemorrhage (SDH) based on Hounsfield Unit measurements (HU) on Computed Tomography (CT) in surviving victims of head injury. Materials and Methods: The study included a total of 100 cases of closed head injury with subdural haemorrhage. The Post-traumatic Time Interval (PTI) varied from 0.5 hours to a maximum of 249 hours, with a mean of 54.2 hours. Results: Statistically significant results were obtained between the HU measurements of the SDH and the post-traumatic intervals and were found to be statistically significant. A rough attempt was made to determine the effect of haematoma volume on attenuation and was found out to be statistically insignificant. Conclusion: The density of the subdural haematoma decreases with increase in the post-traumatic interval that concurs with the limited number of studies being conducted in the past. We concluded that further sorting of cases could be done according to its age with additional research and uniformity in the methodology.
Chapter
Blunt-force injuries are produced when the body is struck with or strikes a blunt object [1–5]. Both mechanisms result in a transfer of kinetic energy that is high enough to produce an injury. Blunt objects have a relatively large area. Examples of blunt objects are almost infinite: fists, shoes, pipes, bricks, bats, hammers, the ground, or parts of vehicles such as cars, trains, or airplanes. A blunt surface produces injuries by torsion, compression, scraping, tearing, shearing, or crushing. Blunt-force injuries occur in many kinds of medico-legal situations and contexts: criminal assaults, physical child abuse, traffic accidents, and falls (criminal, accidental, or suicidal). The severity of the injuries resulting from trauma is a balance between the amount of force, the area over which it is applied, and the duration of the force [2, 6]. In general, the greater the force, the smaller the area, or the shorter the duration over which the force is applied, the greater the injury will be.
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Forensic Radiology is a specialized area of medical imaging utilizing radiological techniques to assist physicians & pathologists in matter pertaining to the law. This article describes the history and modalities of forensic radiology.
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The purpose of this study was to prospectively compare findings from postmortem fetal MR imaging with findings at autopsy. Twenty-six fetuses were imaged on a 1.5-T MR scanner using two-dimensional and high-resolution three-dimensional fast spin-echo techniques immediately before autopsy. The MR images were reviewed independently by three radiologists who evaluated then for major and minor malformations. These findings were then compared with those at autopsy. The 26 subjects had 47 major and 11 minor malformations. All three radiologists correctly identified 37 of the major malformations on the MR images (detection rate, 79%), and at least one of the three reviewers correctly identified 43 of the abnormalities (detection rate, 91%). Only one of the 11 minor anomalies was identified by any reviewer. Reviewers made six false-positive diagnoses. In two cases, both with major CNS malformations, MR imaging was superior to autopsy in defining in situ relationships. Although autopsy remains the study of choice for evaluating causes of fetal death, MR imaging is an excellent alternative when autopsy is refused. Additionally, MR imaging may be a valuable adjunct to autopsy for fetuses with CNS anomalies.
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To review clinical and radiological findings in patients with Duret hemorrhages and to discuss the pathophysiology and differential diagnosis of these lesions. We reviewed the case records of four patients with Duret hemorrhages who had been admitted to the neurological intensive care unit with supratentorial mass lesions. Descending transtentorial and subfalcine herniations were present in all cases. Three patients were admitted with acute subdural hematoma and one with intraparenchymal hemorrhage. Computed tomography revealed the presence of blood in the mesencephalon and upper pons. Three patients died; one survived with severe disabilities. Duret hemorrhages are typically located in the ventral and paramedian aspects of the upper brainstem (mesencephalon and pons). The pathophysiology of Duret hemorrhage remains under debate: arterial origin (stretching and laceration of pontine perforating branches of the basilar artery), versus venous origin (thrombosis and venous infarction). Multifactorial causation seems likely. Duret hemorrhages are delayed, secondary brainstem hemorrhages. They occur in craniocerebral trauma victims with rapidly evolving descending transtentorial herniation. Diagnosis is made on computed tomography of the brain. In most cases the outcome is fatal. On the basis of our observations we believe that arterial hypertension and advanced age are risk factors for the development of Duret hemorrhage.
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Changes in the public perception of postmortem procedures in the United Kingdom have led to reduced numbers of autopsies being performed in the fetus and neonate. When autopsy is performed in this group, the brain is now usually studied without being formalin-fixed, which limits the available information. We evaluated the diagnostic accuracy of postmortem MR imaging of the fetal brain and spine when compared with the reference standard, autopsy. We obtained high-spatial-resolution T2-weighted images (in-plane resolution approximately 0.4 mm) of the brain and spine in 40 fetuses and stillborn neonates (14-42 weeks gestational age) who were referred for autopsy. The MR findings were compared with those of autopsy, the reference standard, which had been performed independently. In eight cases, the autopsy did not provide structural information of the brain or spine, because assessment of the unfixed tissue was impossible. There was agreement between MR and autopsy findings in 31 (97%) of 32 cases in which comparison could be made. Eleven cases showed normal brain, and 20 cases showed a wide range of developmental and acquired abnormalities. The sensitivity of MR was 100%, specificity 92%, positive predictive value 95%, and negative predictive value 100%. MR imaging has a useful role in providing structural information of the central nervous system in fetuses and stillborn neonates.
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Although severe traumatic brain injury (sTBI) is a devastating condition with tremendous public health implications, the epidemiology of this disease has not previously been described in Canada. We sought to define the incidence, risk factors and outcome of patients suffering sTBI in a large Canadian region. A population-based surveillance cohort design was utilized to identify all Calgary Heath Region residents who were victims of trauma with an injury severity score > or = 12. Subsequent application of a specific sTBI case definition defined the final cohort. The annual incidence of sTBI was 11.4 per 100,000 population. The incidence of sTBI was significantly higher for males as compared to females [17.1 vs. 5.9 per 100,000; relative risk (RR) = 2.91, 95% confidence interval; 2.17, 3.94; p<0.0001]. There was a striking increase in the annual age specific population incidence of sTBI observed among those older than 74 years of age. The relative risk among the highest risk group of elderly (>85 years) males as compared to the lowest risk female group (50-64 years) was 19.78 (95% CI; 6.27, 62.3; p<0.0001). One hundred and eight patients died prior to hospital discharge for a mortality rate of 5.1 per 100,000 per year. Severe traumatic brain injury is common among residents of the Calgary Health Region and is associated with a high mortality rate. Males and the elderly are at the highest risk for acquiring sTBI and may represent target groups for preventive efforts.
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Article
CT and MRI have the potential to become useful adjuncts to forensic autopsy in the near future. The examination of fatal injuries facilitates a profound experience in the clinical-radiological examination of these cases; the more severe findings in corpses with autopsy verification can help one to understand the tiny signs seen in clinical cases of surviving victims. We present the case of a 44-year-old male diver who died from severe decompression sickness after rapid ascent from approximately 120 m. Post-mortem CT and MRI studies of the brain and spinal cord revealed extensive gas inclusions in cerebral arteries, spinal arteries and cerebrospinal fluid (CSF) spaces, while the intracranial venous sinuses remained unaffected. These findings were confirmed at autopsy. Appropriate imaging techniques can help forensic pathologists to aim their autopsies at findings that might otherwise remain undetected.
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Article
Traumatic brain injury (TBI) is the major cause of death among young adults in western countries. In the context of a joint Nordic initiative regarding future management of patients with severe TBI, it was of interest to look into the magnitude of the problem and the most recent developments. We have conducted a survey of the epidemiological aspects of TBI deaths in Denmark, Finland, Norway and Sweden for the period 1987-2000. Data were retrieved from the official statistical agencies in the four countries. We have also collected data on the number of operations for acute TBI in the year 2000 from all Nordic hospitals admitting trauma patients. There were almost twice as many deaths from TBI in Finland as in the other Nordic countries. The median mortality rate in Finland was 21.2 per 100,000 per year. The corresponding figures for Denmark were 12.8, Norway 10.5 and Sweden 9.8. Finland also had almost twice as many operations for acute TBI with 10.0 per 100,000 per year, versus 5.1 in Denmark, 4.8 in Norway and 5.7 in Sweden. The mortality rate was about three times higher among males than among females. All countries except Finland had a significant reduction in TBI deaths during the study period. The mortality rate from injuries other than TBI was more or less the same in all four countries. Our findings imply that there are twice as many severe TBIs and related deaths in Finland compared with the other Nordic countries.
Article
Background. — Despite post-mortem examination and autopsy, many cases of sudden infant death (SID) remain unexplained. The aim of this study was to assess usefulness of CT-scan in the Sudden Infant Death Syndrome (SIDS).Population. — Twenty-three cases of SIDS had a post-mortem CT-scan evaluation of skull and brain. The pictures were retrospectively reviewed by several independent radiologists who were unaware of the circumstances of death and results of autopsy.Results. — Aspects of pneumatocele, probably due to lumbar puncture were found in 6 cases. The subarachnoid spaces appeared inexplically hyperdense, as they were not correlated to the results of lumbar puncture and autopsy. The ventricles were normal in size or density. Density of the dural sinuses (superfical and deep) was often increased, an aspect possibly artefactual, due to post-mortem thrombosis.The cerebral parenchyma was often slighty hypodense; microcalcifications due to congenital toxoplasmosis were found in one case.Conclusion. — There was no correlation between the CT-scan imaging and the delay of death and lumbar puncture. Infants with or without subarachnoid hemorrage had the same CT scan findings. The CT-scan has a poor value when autopsy is performed; in its absence, it could be useful for diagnosing post-traumatic intracerebral hematoma.
Article
Purpose: To assess the diagnostic value of postmortem computed tomography (CT) in comparison to autopsy. Materials and Methods: Twenty-seven cadavers were examined by sequential cranial CT and helical CT through the neck,thorax and abdomen and subsequently underwent an autopsy with histomorphologic examination of the pathologic specimens. The findings of CT, autopsy and histology were registered and compared by three radiologists and one specialist for forensic medicine, using a data entry form. Results: In 19 of 27 cases, the findings explaining the cause of death were concordant for CT and autopsy. Intracranial, intraspinal and intracardiac gas accumulations (n = 12) were registered by CT alone. The detection of skull fractures was equal for both methods (n = 3). CT showed diagnostic problems in the assessment of pneumonic infiltrations (n = 16) and pulmonary edema (n = 21). Conclusion: CT is a useful and complementary method to autopsy.
Article
Background: The aim of this prospective study was to estimate annual incidences of hospitalization for severe traumatic brain injury (TBI) (maximum Abbreviated Injury Score in the head region [HAIS] 4 or 5) in a defined population of 2.8 million. Methods: Severe TBI patients were included in the emergency departments in the 19 hospitals of the region. A prospective data form was completed with initial neurologic state, computed tomographic scan lesions, associated injuries, length of unconsciousness, and length of stay in acute care centers. Outcome at the time the patient left acute hospitalization was retrospectively assessed from medical notes. Results: During the 1-year period (1996), 497 residents fulfilled the inclusion criteria, leading to an annual incidence rate of 17.3 per 100,000 population; 58.1% were HAIS5. Mortality rate was 5.2 per 100,000. Men accounted for 71.4% of cases. Median age was 44 years, with a quarter of patients more than 70 years old. Traffic accidents were the most frequent causes (48.3%), but falls accounted for 41.8% of all patients. Age and severity were different according to the major categories of external causes. In HAIS5 patients, 86.5% were considered as comatose (coma lasting more than 24 hours or leading to immediate death) but only 60.9% had an initial Glasgow Coma Scale score < 9. In the HAIS4 group, 7.2% had an initial Glasgow Coma Scale score < 9. Fatality rates were 30.0% in the whole study group, 7.7% in HAIS4, 12.8% in HAIS5 without coma, and 51.2% in HAIS5 with coma. Conclusion: This study shows a decrease in severe TBI incidence when results are compared with another study conducted 10 years earlier in the same region. This is because of a decrease in traffic accidents. However, this results in an increase in the proportion of falls in elderly patients and an increase in the median age in our patients. This increased age influences the mortality rate.
Article
Magnetic resonance images (MRI) of the whole, formalin-fixed brain produce details of pathologic changes deep within brain substance not apparent on external examination. Photographs of these radiographic images present pathologic features in a black-and-white, 2-dimensional format which has proven particularly effective in court before judge and jury. This pathologist has noted acceptance of such photographs in explaining to jurors the details of his testimony in selected cases where brain trauma resulted in a wrongful death. Penetrating missile wounds and blunt impact injuries are particularly well documented by this method.
Article
Tiret L (Institut National de la Santé et de la Recherche Médicale (INSERM), Unité 258, Hōpital Broussais, 96 rue Didot, 75674 Paris Cédex 14, France), Hausherr E, Thicoipe M, Garros B, Maurette P, Castel J P and Hatton F. The epidemiology of head trauma in Aquitaine (France), 1986: A community-based study of hospital admissions and deaths. International Journal of Epidemiology 1990, 19: 133–140. This paper reports the findings of a study of head trauma conducted over a one-year period within a defined region with a population of 2.7 million (Aquitaine, France). It includes cases resulting in death prior to hospitalization or requiring hospitalization. During the one-year period, 391 deaths and 8549 hospital admissions due to head trauma occurred, yielding an annual estimate of 8940 head-injured people. The immediate case-fatality rate was 4.4%. Among non-fatal cases, 80% were mild, 11% moderate and 9% severe. The overall annual incidence was 281/100 000 in both sexes (384 and 185/100 000 in males and females respectively). The annual death rate was 22/100 000 (33 and 12, respectively). Patterns of incidence by age and sex were in general agreement with earlier studies. The main causes of head trauma were traffic accidents (60%) and falls (33%). One-third of hospitalized patients had no injury other than the head trauma. The most frequently associated injuries were those involving extremities, whereas the most severe were those involving the abdomen. The Injury Severity Score (ISS) ranged from 4 to 66, with a mean of 9 and a median of 5. At the eighth day following injury, 25% of hospital-treated patients were still hospitalized and 2% had died. The outcome correlated well with the ISS.
Article
To our knowledge, there are no prospective data in the literature investigating the role of magnetic resonance imaging (MRI) in detecting abnormalities in cadavers to determine the feasibility of this concept. We prospectively studied six cadavers (three stillborn infants, one infant, and two adults) with a 0.15 T resistive magnet. The images obtained allowed detection of abnormalities in multiple organs. Although autopsy was superior to MRI in detecting very small abnormalities, MRI was equal to autopsy in detecting gross cranial, pulmonary, abdominal, and vascular pathology in this small series. In addition, MRI was superior to autopsy in detecting air and fluid in potential body spaces. Preautopsy MRI may be an alternate method in restricted or denied autopsies and may provide an additional MRI research and educational tool.
Article
To improve interpretation of intracranial computed tomographic findings in vivo, postmortem computed tomography was correlated directly with autopsy findings in 105 specimens of human stillborn and live-birth infants, ranging in age from gestational week 13 to postnatal month 18. This study identifies the typical computed tomographic appearance of intradural and other hemorrhages, attempts to correlate the type of hemorrhage with brain maturity, and documents that postmortem computed tomography is useful to the neuropathologist as a supplementary method complementing the traditional postmortem examination.
Article
Bei 24 Hirnen von Personen, die an den Folgen eines Kopfschusses starben, und zwei Patienten mit frischen Kopfschußverletzungen wurde die Verwendbarkeit der Computertomographie (CT) bei der Rekonstruktion von Schußverletzungen und als neuropathologische und forensische Zusatzmethode geprüft. Die morphologischen postmortalen und intravitalen Untersuchungsergebnisse werden beschrieben und mit der Bildinformation aus Ultraschallrotationscompoundscans von Hirnpräparaten verglichen. Die CT zeigt eine gute Übereinstimmung mit den pathologisch-anatomischen Befunden. Der Vergleich mit der Ultraschallabbildung belegt eine Bildqualität der letzteren, die zwischen der Computertomographie und der hirnpathologischen fotografischen Direktabbildung liegt. Beide Methoden werden als geeignete Ergänzung der neuropathologischen bzw. forensischen Beurteilung von Schußverletzungen angesehen. Summary The value of CT was assessed in 24 patients who died of cerebral gunshot injuries and in two patients with more recent injuries in order to reconstruct the mode of injury and for adding forensic information. The post-mortem and intravital appearances are described and are compared with ultrasound rotation compound scans of the isolated brains. CT showed good agreement with pathological findings. Ultrasound produced images with an accuracy between CT and photographs of the brain specimen. Both methods are regarded as valuable additions to the pathological and forensic information concerning gunshot injuries.
Article
The aim of this study was to validate brain imaging techniques in the preterm infant. A homogeneous group of very immature (less than 32 week) neonates dying in the neonatal period were sequentially scanned with linear-array real-time ultrasound scans, and after death with compound B static sector ultrasound and high-resolution computed tomography (CT) scans. All three imaging techniques were correlated with the autopsy results. All germinal matrix bleeds greater than 5mm in size and intraventricular hemorrhages associated with ventricular dilation or distortion were accurately diagnosed. In the immature infant it was difficult to distinguish the normal highly vascular germinal matrix and choroid plexus from hemorrhage into the brain or ventricles, respectively. Further studies that address the questions of accurate timing and incidence of bleeds must consider the spatial resolution of the individual scanner, the maturity of the brain, the site and size of the lesion, and the evolution of the lesion. For the diagnosis of major hemorrhagic lesions in the preterm infant, either ultrasound or CT scans may be used with confidence.
Article
A possible way to circumvent the continuing decline in the number of autopsies is to perform computed tomography after death. The present study compares the pathologic findings of postmortem CT tomography (PMCT) in trauma fatalities with those disclosed upon conventional forensic autopsy. Within 6 hours of death, the bodies of 25 trauma victims underwent total body CT scanning, all with permission of the relatives, followed by conventional autopsy in 13 cases under court order. The pathologist and roentgenologist were unaware of each other's findings. The pathologic findings of PMCT plus conventional autopsy provided more information than either examination alone. Of the total 127 pathologic findings, 44.9% were diagnosed by both conventional autopsy and PMCT, 29.9% were not revealed by PMCT, whereas conventional autopsy missed 25.2%, and PMCT detected more bone injuries than did autopsy, whereas the latter was superior to PMCT in discovering soft-tissue pathologic states. In all, PMCT revealed 70.5% and autopsy 74.8% of the pathologic states. Although PMCT was not more effective than conventional autopsy in exposing pathologic entities, it increased the yield of findings when combined with conventional autopsy. Where conventional autopsy is unattainable, PMCT may be effective in shedding light on the pathologic state and mechanism of death in trauma fatalities.
Article
To assess postmortem radiologic and pathologic findings by using modern imaging and autopsy techniques in two recent cases of judicial hangings. Cervical spine radiography; computed tomography (CT) of the head, neck, and chest; magnetic resonance (MR) imaging of the head and cervical spine; and vertebral angiography were followed by a complete autopsy, including head and neck dissection. The first case (subaural knot) showed cervical spine ligamentous injury and partial disruption of the vertebral arteries without vertebral subluxation or injury to the cervical cord. The second case (submental knot) showed complete ligamentous disruption and subluxation at C2-3 with complete cord transection. In both cases, minimally displaced transverse process fractures were present, and CT and MR imaging of the head showed diffuse subarachnoid hemorrhage. The extent and distribution of injuries differed markedly in the two cases. The first case involved loss of consciousness probably from subarachnoid hemorrhage or cerebral hypoxia, followed by death due to cerebral anoxia. The second case involved a major spinal cord injury with subarachnoid hemorrhage.
Article
We report a woman with fatal head injuries in whom CT demonstrated pneumocephalus and diffuse intravascular air.
Article
Over 200 brains were examined by postmortem magnetic resonance imaging to determine the utility of this imaging procedure as an adjunct to the standard postmortem examination of the brain and spinal cord. One unembalmed cadaver was also studied using a conventional 1.5-tesla (T) field-strength unit, and three formalin-fixed sections of the hippocampus were imaged using a high field-strength (7.0-T) prototype imaging system. The postmortem magnetic resonance images proved to be an invaluable aid that complemented the standard pathologic examination of the brain and spinal cord. The compelling advantages of this postmortem radiographic procedure included the three-dimensional aspects of the images; the ability to detect mineral (ie, iron) deposits; small focal lesions such as hemorrhages or infarcts; and the ability to evaluate the extent of cerebral edema. For the same reasons, as well as its archival potential for documenting the topographic distribution of pathologic processes, this technique has great promise for forensic cases. High field-strength (7.0-T) imaging brought the resolution of magnetic resonance to the microscopic level and reaffirmed the potential value of magnetic resonance imaging for diagnostic and investigative studies in which both the histologic and fine radiologic features of lesions are of interest.
Article
We studied 18 formalin-fixed brains using MRI, and correlated our data with subsequent gross and microscopic examinations. 9 of our patients died from brain diseases (stroke due to infarction 4, stroke due to hemorrhage 1, encephalitis 2, head injury 1, brain tumor 1). 9 of our patients died from non-CNS diseases (stomach cancer 1, colon cancer 1, liver cirrhosis 1, myocardial infarction 2, trauma 4). In MRI of postmortem brain, T1WI and T 2WI was able to clearly show the myelination process of brainstem, basal ganglia, internal capsule and optic radiation in a 2 months-old-boy. The findings were similar to MRI of live infants. In normal adult postmortem brains, the T1WI showed a relatively low signal intensity of white matter as compared to gray matter. The pictures were similar to proton density images, not T1WI of normal adult brains. The reason why the signal intensity of the white matter was lower than the gray matter may have been due to lysis of lipid of myelin sheath in the formalin solution. Postmortem MRI was able to detect the periventricular hyperintensity (corresponding to arteriosclerotic encephalopathy) and subcortical hyperintensity spots (which corresponding to the widening of the Virchow-Robin perivascular space because of arteriosclerosis) in the brains of our elderly patients. Postmortem MRI detected the intracerebral hemorrhage, which appeared as a dark signal in both short and long TR images. However, MRI did not show blood in the ventricles, sulci, or superficial hemorrhages in the cortex of brain. Brain edema was revealed in the postmortem MRI and appeared as low signal intensity in T1WI and hyperintensity in T2WI. It was associated with a significant mass effect.(ABSTRACT TRUNCATED AT 250 WORDS)
Article
We investigated the correlation between postmortem magnetic resonance imaging (MRI) of the head and autopsy findings in suspected child abuse. Postmortem MRI was performed within 24 h of death and before autopsy in 11 children 2 years old or younger whose deaths were unexplained or suspected to be due to child abuse. MRI findings were available to the pathologist at the time of autopsy. In eight cases of death from non-accidental trauma, cerebral edema, contusion, shearing injury, ischemia, and infarction were well demonstrated on MRI. In the three deaths determined not to be due to trauma, there were no false-positive MRI findings. Autopsy was superior in detection of subarachnoid hemorrhage, suture separation, extracranial injuries, and very small subdural hematomas. MRI findings were useful in directing the autopsy and brain-cutting to focal areas of abnormality. Postmortem MRI and autopsy are complementary, and each may disclose abnormalities missed by the other. In half of the eight cases of child abuse examined, the combination of MRI and autopsy added valuable information compared with the results of autopsy alone. Postmortem MRI can be a valuable addition to autopsy findings in the investigation of fatalities potentially due to child abuse.
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Despite post-mortem examination and autopsy, many cases of sudden infant death (SID) remain unexplained. The aim of this study was to assess usefulness of CT-scan in the Sudden Infant Death Syndrome (SIDS). Twenty-three cases of SIDS had a post-mortem CT-scan evaluation of skull and brain. The pictures were retrospectively reviewed by several independent radiologists who were unaware of the circumstances of death and results of autopsy. Aspects of pneumatocele, probably due to lumbar puncture were found in 6 cases. The subarachnoid spaces appeared inexplically hyperdense, as they were not correlated to the results of lumbar puncture and autopsy. The ventricles were normal in size or density. Density of the dural sinuses (superfical and deep) was often increased, an aspect possibly artefactual, due to post-mortem thrombosis. The cerebral parenchyma was often slighty hypodense; microcalcifications due to congenital toxoplasmosis were found in one case. There was no correlation between the CT-scan imaging and the delay of death and lumbar puncture. Infants with or without subarachnoid hemorrage had the same CT scan findings. The CT-scan has a poor value when autopsy is performed; in its absence, it could be useful for diagnosing post-traumatic intracerebral hematoma.
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AT present necropsy is done in less than 60% of cases of perinatal death in the UK, despite the value of the procedure to the bereaved parents and their doctors. This low rate reflects the difficulty in discussing the examination during the acute distress after the death of a baby, and the personal and religious objections of many parents to necropsy. We compared post-mortem magnetic resonance imaging (MRI) of the fetus with internal perinatal necropsy to assess whether MRI examination is a feasible option for the 40% of cases where consent for necropsy is not given or requested. We examined 20 stillborn, miscarried, or aborted fetuses by MRI and necropsy. Scanning was done in a 1.5 T system, in accordance with our protocol, immediately before necropsy. The MRI and necropsy findings were compared to assess how much diagnostic information was obtained by each technique. In eight of the 20 cases the two examinations were in total agreement about the abnormalities present. In eight cases the necropsy provided more detailed information than MRI examination, but in four cases the MRI information was more extensive than that obtained at necropsy. In two of the latter cases, abnormalities of the central nervous system were seen only on MRI. Thus, in 12 (60%) of the 20 cases studied, MRI had equivalent or better diagnostic sensitivity than internal necropsy examination; in 18 (90%) of the 20 cases the two examinations were of similar clinical significance. MRI of the stillborn or aborted fetus provides non-invasive access to information previously available only from necropsy.
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MR imaging of post mortem brains has the potential to yield volumetric information and define the extent of structural changes prior to pathological examination. Although standard T2-weighted clinical imaging sequences have been used for the examination of formalin-fixed brains, these protocols may not yield optimum contrast. We examined the effect of varying durations of formalin fixation on the transverse relaxation time (T2) and the tissue spin density. Three post mortem brains were examined weekly during formalin fixation from the unfixed state to 35 days fixation. Standard MR spin-echo imaging was used at 5 echo times (20-100 ms) to calculate transverse relaxation time (T2) and spin density. T2 decreased significantly (ANOVA, p<0.001) in both grey and white matter by 7 days fixation and there was a further (but non-significant) trend towards lower values between 7 and 35 days. Grey and white matter T2 times converged with fixation. Conversely, the grey to white matter spin density ratio increased from 1.19+/-0.01 to 1.54+/-0.06 over five weeks of fixation. Our results suggest that spin density-weighted imaging sequences would provide improved grey to white matter contrast over T2-weighted sequences.