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1.
Int J Legal Med ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689177

RESUMO

BACKGROUND: The increased use of virtual bone images in forensic anthropology requires a comprehensive study on the observational errors between dry bones and CT reconstructions. Here, we focus on the consistency of nonmetric sex estimation traits on the human skull. MATERIALS AND METHODS: We scored nine nonmetric traits on dry crania and mandibles (n = 223) of archaeological origin and their CT reconstructions. Additionally, we 3D surface scanned a subsample (n = 50) and repeated our observations. Due to the intricate anatomy of the mental eminence, we split it into two separate traits: the bilateral mental tubercles and the midsagittal mental protuberance. We provide illustrations and descriptions for both these traits. RESULTS: We obtained supreme consistency values between the CT and 3D surface modalities. The most consistent cranial traits were the glabella and the supraorbital margin, followed by the nuchal crest, zygomatic extension, mental tubercles, mental protuberance, mental eminence, mastoid process and ramus flexure, in descending order. The mental tubercles show higher consistency scores than the mental eminence and the mental protuberance. DISCUSSION: The increased interchangeability of the virtual modalities with each other as compared to the dry bone modality could be due to the lack of tactility on both the CT and surface scans. Moreover, tactility appears less essential with experience than a precise trait description. Future studies could revolve around the most consistent cranial traits, combining them with pelvic traits from a previous study, to test for accuracy.

2.
Int J Legal Med ; 137(6): 1839-1852, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37336820

RESUMO

BACKGROUND: Computed tomography (CT) scans are a convenient means to study 3D reconstructions of bones. However, errors associated with the different nature of the observation, e.g. visual and tactile (on dry bone) versus visual only (on a screen) have not been thoroughly investigated. MATERIALS AND METHODS: We quantified the errors between modalities for sex estimation protocols of nonmetric (categorical and ordinal) and metric data, using 200 dry pelves of archaeological origin and the CT reconstructions of the same bones. In addition, we 3D surface scanned a subsample of 39 pelves to compare observations with dry bone and CT data. We did not focus on the sex estimation accuracy but solely on the consistency of the scoring, hence, the interchangeability of the modalities. RESULTS: Metric data yielded the most consistent results. Among the nonmetric protocols, ordinal data performed better than categorical data. We applied a slightly modified description for the trait with the highest errors and grouped the traits according to consistency and availability in good, intermediate, and poor. DISCUSSION: The investigated modalities were interchangeable as long as the trait definition was not arbitrary. Dry bone (gold standard) performed well, and CT and 3D surface scans performed better. We recommend researchers test their affinity for using virtual modalities. Future studies could use our consistency analysis and combine the best traits, validating their accuracy on various modalities.

3.
Int J Legal Med ; 133(6): 1861-1867, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30788563

RESUMO

BACKGROUND: The goal of this study was to evaluate if unenhanced PMCT HU values of liver pathologies differ from post-mortem HU values of non-pathologic liver tissue. METHODS: Liver HU values were measured in five liver segments in PMCT unenhanced datasets of 214 forensic cases (124 male, 90 female, mean age 54.3 years). Liver HU values were compared with corresponding histologic liver findings. HU values of non-pathologic livers were compared to HU values of liver pathologies. RESULTS: A total of 64 non-pathologic livers (mean HU 58.32, SD 8.91) were assessed. Histologic diagnosed liver pathologies were as follows: steatosis (n = 121 (grade I n = 61, grade II n = 37, grade III n = 23)), fibrosis (n = 10), and cirrhosis (n = 19). HU values of the livers exhibiting severe steatosis (mean HU 32.44, SD 13.76), fibrosis (mean HU 44.7, SD 16.31), and cirrhosis (mean HU 50.59, SD 9.42) significantly differed to HU values of non-pathologic livers at ANOVA testing. CONCLUSION: PMCT unenhanced liver HU value measurements may be used as an additional method to detect unspecific liver-pathology. Values below 30 HU may specifically indicate severe steatosis.


Assuntos
Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Tomografia Computadorizada por Raios X , Autopsia , Causas de Morte , Fígado Gorduroso/classificação , Feminino , Patologia Legal , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Imagem Corporal Total
4.
Int J Legal Med ; 131(1): 199-210, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27766411

RESUMO

Segmentation of the lungs using post-mortem computed tomography (PMCT) data was so far not feasible due to post-mortem changes such as internal livores. Recently, an Osirix plug-in has been developed allowing automatically segmenting lungs also in PMCT data. The aim of this study was to investigate if the Hounsfield unit (HU) profiles obtained in PMCT data of the segmented lung tissue present with specific behaviour in relation to the cause of death. In 105 PMCT data sets of forensic cases, the entire lung volumes were segmented using the Mia Lite plug-in on Osirix. HU profiles of the lungs were generated and correlated to cause of death groups as assessed after forensic autopsy (cardiac death, fatal haemorrhage, craniocerebral injury, intoxication, drowning, hypothermia, hanging and suffocation). Especially cardiac death cases, intoxication cases, fatal haemorrhage cases and hypothermia cases showed very specific HU profiles. In drowning, the profiles showed two different behaviours representing wet and dry drowning. HU profiles rather varied in craniocerebral injury cases, hanging cases as well as in suffocation cases. HU profiles of the lungs segmented from PMCT data may support the cause of death diagnosis as they represent specific morphological changes in the lungs such as oedema, congestion or blood loss. Especially in cardiac death, intoxication, fatal haemorrhage, hypothermia and drowning cases, HU profiles may be very supportive for the forensic pathologist.


Assuntos
Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Asfixia/patologia , Lesões Encefálicas/patologia , Causas de Morte , Criança , Pré-Escolar , Afogamento/patologia , Feminino , Cardiopatias/patologia , Hemorragia/patologia , Humanos , Hipotermia/patologia , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Intoxicação/patologia , Estudos Prospectivos , Adulto Jovem
5.
Int J Legal Med ; 131(5): 1369-1376, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28624986

RESUMO

OBJECTIVES: The present study aimed to evaluate if simultaneous temperature-corrected T1, T2, and proton density (PD) 1.5 T post-mortem MR quantification [quantitative post-mortem magnetic resonance imaging (QPMMRI)] is feasible for characterizing and discerning non-pathologic upper abdominal organs (liver, spleen, pancreas, kidney) with regard to varying body temperatures. METHODS: QPMMRI was performed on 80 corpses (25 females, 55 males; mean age 56.2 years, SD 17.2) prior to autopsy. Core body temperature was measured during QPMMRI. Quantitative T1, T2, and PD values were measured in the liver, pancreas, spleen, and left kidney and temperature corrected to 37 °C. Histologic examinations were conducted on each measured organ to determine non-pathologic organs. Quantitative T1, T2, and PD values of non-pathologic organs were ANOVA tested against values of other non-pathologic organ types. RESULTS: Based on temperature-corrected quantitative T1, T2, and PD values, ANOVA testing verified significant differences between the non-pathologic liver, spleen, pancreas, and left kidneys. CONCLUSIONS: Temperature-corrected 1.5 T QPMMRI based on T1, T2, and PD values may be feasible for characterization and differentiation of the non-pathologic liver, spleen, pancreas, and kidney. The results may provide a base for future specific pathology diagnosis of upper abdominal organs in post-mortem imaging.


Assuntos
Temperatura Corporal , Rim/diagnóstico por imagem , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Pâncreas/diagnóstico por imagem , Baço/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Mudanças Depois da Morte , Estudos Prospectivos
6.
Int J Legal Med ; 130(6): 1599-1601, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27169675

RESUMO

Through the widespread use of postmortem computed tomography, inner livores of the lungs have become a frequently observed phenomenon in the field of forensic medicine. Yet their time-dependent development, notably in comparison with the widely studied external livores, remains poorly understood. We present a unique homicide case where the victim was discovered in supine position with correspondent external livores fixed exclusively on the rear side. Yet upon postmortem computed tomography, the victim presented pronounced inner livores within the depending dorsal areas of both lungs but also vertical sedimentation levels solely within the right lung, suggesting an initial right-hand side position and a postmortem re-positioning of the body. Interestingly, this was consistent with tangible hints of postmortem manipulation on-site. It is likely that this repositioning occurred sometime during the early postmortem interval (<6 h) as the external livores have completely rearranged to the final supine position. The presented case suggests different development patterns of inner and outer livores, highlighting the necessity for controlled studies that explore the formation and fixation processes of livor mortis in internal organs. A better understanding of these issues can prove useful in forensic examinations.


Assuntos
Homicídio , Pulmão/diagnóstico por imagem , Pulmão/patologia , Mudanças Depois da Morte , Idoso , Humanos , Masculino , Decúbito Dorsal , Tomografia Computadorizada por Raios X
7.
Int J Legal Med ; 130(1): 191-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26400026

RESUMO

In their daily forensic casework, the authors experienced discrepancies of tracheobronchial content findings between postmortem computed tomography (PMCT) and autopsy to an extent previously unnoticed in the literature. The goal of this study was to evaluate such discrepancies in routine forensic cases. A total of 327 cases that underwent PMCT prior to routine forensic autopsy were retrospectively evaluated for tracheal and bronchial contents according to PMCT and autopsy findings. Hounsfield unit (HU) values of tracheobronchial contents, causes of death, and presence of pulmonary edema were assessed in mismatching and matching cases. Comparing contents in PMCT and autopsy in each of the separately evaluated compartments of the respiratory tract low positive predictive values were assessed (trachea, 38.2%; main bronchi, 40%; peripheral bronchi, 69.1%) indicating high discrepancy rates. The majority of tracheobronchial contents were viscous stomach contents in matching cases and low radiodensity materials (i.e., HU < 30) in mismatching cases. The majority of causes of death were cardiac related in the matching cases and skull/brain trauma in the mismatching cases. In mismatching cases, frequency of pulmonary edema was significantly higher than in matching cases. It can be concluded that discrepancies in tracheobronchial contents observed between PMCT and routine forensic autopsy occur in a considerable number of cases. Discrepancies may be explained by the runoff of contents via nose and mouth during external examination and the flow back of tracheal and main bronchial contents into the lungs caused by upright movement of the respiratory tract at autopsy.


Assuntos
Autopsia , Brônquios/patologia , Broncografia , Traqueia/diagnóstico por imagem , Traqueia/patologia , Feminino , Patologia Legal , Conteúdo Gastrointestinal/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Edema Pulmonar/diagnóstico por imagem , Edema Pulmonar/patologia , Aspiração Respiratória/diagnóstico por imagem , Aspiração Respiratória/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
8.
Int J Legal Med ; 130(4): 1071-1080, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26872469

RESUMO

Recently, post-mortem MR quantification has been introduced to the field of post-mortem magnetic resonance imaging. By usage of a particular MR quantification sequence, T1 and T2 relaxation times and proton density (PD) of tissues and organs can be quantified simultaneously. The aim of the present basic research study was to assess the quantitative T1, T2, and PD values of regular anatomical brain structures for a 1.5T application and to correlate the assessed values with corpse temperatures. In a prospective study, 30 forensic cases were MR-scanned with a quantification sequence prior to autopsy. Body temperature was assessed during MR scans. In synthetically calculated T1, T2, and PD-weighted images, quantitative T1, T2 (both in ms) and PD (in %) values of anatomical structures of cerebrum (Group 1: frontal gray matter, frontal white matter, thalamus, internal capsule, caudate nucleus, putamen, and globus pallidus) and brainstem/cerebellum (Group 2: cerebral crus, substantia nigra, red nucleus, pons, cerebellar hemisphere, and superior cerebellar peduncle) were assessed. The investigated brain structures of cerebrum and brainstem/cerebellum could be characterized and differentiated based on a combination of their quantitative T1, T2, and PD values. MANOVA testing verified significant differences between the investigated anatomical brain structures among each other in Group 1 and Group 2 based on their quantitative values. Temperature dependence was observed mainly for T1 values, which were slightly increasing with rising temperature in the investigated brain structures in both groups. The results provide a base for future computer-aided diagnosis of brain pathologies and lesions in post-mortem magnetic resonance imaging.


Assuntos
Autopsia , Encéfalo/anatomia & histologia , Imageamento por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Temperatura Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mudanças Depois da Morte , Estudos Prospectivos , Adulto Jovem
9.
Eur Radiol ; 25(7): 2067-73, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25591749

RESUMO

OBJECTIVES: Recently, an MRI quantification sequence has been developed which can be used to acquire T1- and T2-relaxation times as well as proton density (PD) values. Those three quantitative values can be used to describe soft tissue in an objective manner. The purpose of this study was to investigate the applicability of quantitative cardiac MRI for characterization and differentiation of ischaemic myocardial lesions of different age. MATERIALS AND METHODS: Fifty post-mortem short axis cardiac 3 T MR examinations have been quantified using a quantification sequence. Myocardial lesions were identified according to histology and appearance in MRI images. Ischaemic lesions were assessed for mean T1-, T2- and proton density values. Quantitative values were plotted in a 3D-coordinate system to investigate the clustering of ischaemic myocardial lesions. RESULTS: A total of 16 myocardial lesions detected in MRI images were histologically characterized as acute lesions (n = 8) with perifocal oedema (n = 8), subacute lesions (n = 6) and chronic lesions (n = 2). In a 3D plot comprising the combined quantitative values of T1, T2 and PD, the clusters of all investigated lesions could be well differentiated from each other. CONCLUSION: Post-mortem quantitative cardiac MRI is feasible for characterization and discrimination of different age stages of myocardial infarction. KEY POINTS: • MR quantification is feasible for characterization of different stages of myocardial infarction. • The results provide the base for computer-aided MRI cardiac infarction diagnosis. • Diagnostic criteria may also be applied for living patients.


Assuntos
Infarto do Miocárdio/patologia , Miocárdio/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Autopsia , Criança , Estudos de Viabilidade , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Eur Radiol ; 25(8): 2381-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25636417

RESUMO

OBJECTIVES: To investigate and correct the temperature dependence of postmortem MR quantification used for soft tissue characterization and differentiation in thoraco-abdominal organs. MATERIAL AND METHODS: Thirty-five postmortem short axis cardiac 3-T MR examinations were quantified using a quantification sequence. Liver, spleen, left ventricular myocardium, pectoralis muscle and subcutaneous fat were analysed in cardiac short axis images to obtain mean T1, T2 and PD tissue values. The core body temperature was measured using a rectally inserted thermometer. The tissue-specific quantitative values were related to the body core temperature. Equations to correct for temperature differences were generated. RESULTS: In a 3D plot comprising the combined data of T1, T2 and PD, different organs/tissues could be well differentiated from each other. The quantitative values were influenced by the temperature. T1 in particular exhibited strong temperature dependence. The correction of quantitative values to a temperature of 37 °C resulted in better tissue discrimination. CONCLUSION: Postmortem MR quantification is feasible for soft tissue discrimination and characterization of thoraco-abdominal organs. This provides a base for computer-aided diagnosis and detection of tissue lesions. The temperature dependence of the T1 values challenges postmortem MR quantification. Equations to correct for the temperature dependence are provided. KEY POINTS: • Postmortem MR quantification is feasible for soft tissue discrimination and characterization • Temperature dependence of the T1 values challenges the MR quantification approach • The results provide the basis for computer-aided postmortem MRI diagnosis • Diagnostic criteria may also be applied for living patients.


Assuntos
Autopsia/métodos , Temperatura Corporal/fisiologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Análise de Variância , Criança , Estudos de Viabilidade , Feminino , Coração/anatomia & histologia , Ventrículos do Coração/anatomia & histologia , Humanos , Imageamento Tridimensional , Fígado/anatomia & histologia , Masculino , Pessoa de Meia-Idade , Músculos Peitorais , Baço/anatomia & histologia , Gordura Subcutânea/anatomia & histologia , Adulto Jovem
11.
Int J Legal Med ; 129(5): 1127-36, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26162597

RESUMO

The purpose of the present study was to investigate whether serous fluids, blood, cerebrospinal fluid (CSF), and putrefied CSF can be characterized and differentiated in synthetically calculated magnetic resonance (MR) images based on their quantitative T1, T2, and proton density (PD) values. Images from 55 postmortem short axis cardiac and 31 axial brain 1.5-T MR examinations were quantified using a quantification sequence. Serous fluids, fluid blood, sedimented blood, blood clots, CSF, and putrefied CSF were analyzed for their mean T1, T2, and PD values. Body core temperature was measured during the MRI scans. The fluid-specific quantitative values were related to the body core temperature. Equations to correct for temperature differences were generated. In a 3D plot as well as in statistical analysis, the quantitative T1, T2 and PD values of serous fluids, fluid blood, sedimented blood, blood clots, CSF, and putrefied CSF could be well differentiated from each other. The quantitative T1 and T2 values were temperature-dependent. Correction of quantitative values to a temperature of 37 °C resulted in significantly better discrimination between all investigated fluid mediums. We conclude that postmortem 1.5-T MR quantification is feasible to discriminate between blood, serous fluids, CSF, and putrefied CSF. This finding provides a basis for the computer-aided diagnosis and detection of fluids and hemorrhages.


Assuntos
Sangue , Líquidos Corporais , Líquido Cefalorraquidiano , Imageamento por Ressonância Magnética , Mudanças Depois da Morte , Temperatura Corporal , Encéfalo/patologia , Feminino , Patologia Legal , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Miocárdio/patologia , Pericárdio/patologia , Trombose/patologia
12.
Eur Radiol ; 23(5): 1266-70, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23242001

RESUMO

OBJECTIVES: To investigate unenhanced postmortem 3-T MR imaging (pmMRI) for the detection of pulmonary thrombembolism (PTE) as cause of death. METHODS: In eight forensic cases dying from a possible cardiac cause but with homogeneous myocardium at cardiac pmMRI, additional T2w imaging of the pulmonary artery was performed before forensic autopsy. Imaging was carried out on a 3-T MR system in the axial and main pulmonary artery adapted oblique orientation in situ. In three cases axial T2w pmMRI of the lower legs was added. Validation of imaging findings was performed during forensic autopsy. RESULTS: All eight cases showed homogeneous material of intermediate signal intensity within the main pulmonary artery and/or pulmonary artery branches. Autopsy confirmed the MR findings as pulmonary artery thrombembolism. At lower leg imaging unilateral dilated veins and subcutaneous oedema with or without homogeneous material of intermediate signal intensity within the popliteal vein were found. CONCLUSIONS: Unenhanced pmMRI demonstrates pulmonary thrombembolism in situ. PmMR may serve as an alternative to clinical autopsy, especially when consent cannot be obtained. KEY POINTS: • Postmortem MRI (pmMRI) provides an alternative to clinical autopsy • Fatal pulmonary thrombembolism (PTE) can now be diagnosed using postmortem MRI (pmMRI). • Special attention has to be drawn to the differentiation of postmortem clots.


Assuntos
Imageamento por Ressonância Magnética/métodos , Embolia Pulmonar/patologia , Autopsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Emerg Radiol ; 20(4): 285-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23504333

RESUMO

The objective of this study was to determine if area measurements of pleural fluid on computed tomography (CT) reflect the actual pleural fluid volume (PEvol) as measured at autopsy, to establish a formula to estimate the volume of pleural effusion (PEest), and to test the accuracy and observer reliability of PEest.132 human cadavers, with pleural effusion were divided into phase 1 (n = 32) and phase 2 (n = 100). In phase 1, PEvol was compared to area measurements on axial (axA), sagittal (sagA), and coronal (corA) CT images. Linear regression analysis was used to create a formula to calculate PEest. In phase 2, intra-class correlation (ICC) was used to assess inter-reader reliability and determine the agreement between PEest and PEvol. PEvol correlated to a higher degree to axA (r s mean = 0.738; p < 0.001) than to sagA (r s mean = 0.679, p < 0.001) and corA (r s mean = 0.709; p < 0.001). PEest can be established with the following formula: axA × 0.1 = PEest. Mean difference between PEest and PEvol was less than 40 mL (ICC = 0.837-0.874; p < 0.001). Inter-reader reliability was higher between two experienced readers (ICC = 0.984-0.987; p < 0.001) than between an inexperienced reader and both experienced readers (ICC = 0.660-0.698; p < 0.001). Pleural effusions may be quantified in a rapid, reliable, and reasonably accurate fashion using single area measurements on CT.


Assuntos
Derrame Pleural/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Autopsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Software
14.
Forensic Sci Med Pathol ; 9(1): 68-72, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22956431

RESUMO

The body of a 59 year old woman underwent postmortem computed tomography (PMCT) examination prior to forensic autopsy, using a 256 slice multidetector row computed tomography scanner. A large left tension pneumothorax detected on the PMCT was considered to be a likely cause of death and this was confirmed at autopsy. In addition there was an unsuspected PMCT finding of a probable gunshot injury traversing the right orbit, facial bones and frontal sinus. The autopsy technique was adjusted accordingly and PMCT findings confirmed. PMCT in this case was not only diagnostic of cause of death, but also revealed retained projectile fragments of an old gunshot wound to the face. Without prior imaging such findings would have been undetected at autopsy. This case further underscores the contribution of routine PMCT examination to forensic autopsy practice.


Assuntos
Corpos Estranhos , Balística Forense/métodos , Achados Incidentais , Tomografia Computadorizada Multidetectores , Pneumotórax/diagnóstico por imagem , Ferimentos por Arma de Fogo/diagnóstico por imagem , Autopsia , Causas de Morte , Evolução Fatal , Feminino , Humanos , Pessoa de Meia-Idade , Pneumotórax/patologia , Valor Preditivo dos Testes , Ferimentos por Arma de Fogo/patologia
15.
Forensic Sci Med Pathol ; 9(3): 327-32, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23512303

RESUMO

The aim of this study was to assess the potential of monoenergetic computed tomography (CT) images to reduce beam hardening artifacts in comparison to standard CT images of dental restoration on dental post-mortem CT (PMCT). Thirty human decedents (15 male, 58 ± 22 years) with dental restorations were examined using standard single-energy CT (SECT) and dual-energy CT (DECT). DECT data were used to generate monoenergetic CT images, reflecting the X-ray attenuation at energy levels of 64, 69, 88 keV, and at an individually adjusted optimal energy level called OPTkeV. Artifact reduction and image quality of SECT and monoenergetic CT were assessed objectively and subjectively by two blinded readers. Subjectively, beam artifacts decreased visibly in 28/30 cases after monoenergetic CT reconstruction. Inter- and intra-reader agreement was good (k = 0.72, and k = 0.73 respectively). Beam hardening artifacts decreased significantly with increasing monoenergies (repeated-measures ANOVA p < 0.001). Artifact reduction was greatest on monoenergetic CT images at OPTkeV. Mean OPTkeV was 108 ± 17 keV. OPTkeV yielded the lowest difference between CT numbers of streak artifacts and reference tissues (-163 HU). Monoenergetic CT reconstructions significantly reduce beam hardening artifacts from dental restorations and improve image quality of post-mortem dental CT.


Assuntos
Artefatos , Restauração Dentária Permanente , Restauração Dentária Temporária , Patologia Legal/métodos , Tomografia Computadorizada por Raios X , Adulto , Idoso , Análise de Variância , Autopsia , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Estudos Retrospectivos
16.
Forensic Sci Int ; 353: 111878, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37980856

RESUMO

BACKGROUND: A 3D sequence was introduced to unenhanced post-mortem cardiac magnetic resonance imaging (PMCMR) to enable multiplanar coronary artery image analysis and to investigate its diagnostic accuracy for the diagnosis of coronary artery stenosis and thrombosis. MATERIALS AND METHODS: N = 200 forensic cases with suspected coronary artery pathology underwent 3 Tesla PMCMR (sequence used: T2 weighted transversal 3D turbo spin echo) before autopsy. Main coronary artery stenosis and thrombosis were assessed in PMCMR by multiplanar image analysis by two observers. Coronary artery histology was determined as the gold standard and compared to PMCMR. Sensitivity, specificity, negative (NPV) and positive predictive values (PPV) with 95% confidence intervals were calculated. RESULTS: For all coronary arteries combined, sensitivity was 75% (PPV 73%) for the diagnosis of stenosis and 72% (PPV 71%) for the diagnosis of thrombosis. Specificity was 92% (NPV 90%) for correct diagnosis of non-existing stenosis and 97% (NPV 97%) for non-existing thrombosis. Sensitivity for correct diagnosis of different degrees of stenosis ranged between 67% and 80% (PPVs 67-82%); specificity ranged between 96% and 99% (NPVs 96-99%). CONCLUSION: Multiplanar PMCMR coronary artery stenosis and thrombosis assessment based on an unenhanced T2 weighted 3D sequence provide moderate sensitivity and high specificity for the diagnosis of coronary artery stenosis and/or thrombosis. Hence, 3D T2w PMCMR cannot reliably detect existing coronary artery stenosis and thrombosis but may be particularly useful for the exclusion of stenosis or thrombosis of the main coronary arteries.


Assuntos
Estenose Coronária , Trombose , Humanos , Constrição Patológica , Sensibilidade e Especificidade , Imageamento por Ressonância Magnética/métodos , Trombose/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem
17.
Forensic Sci Int ; 327: 110984, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482282

RESUMO

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.


Assuntos
Temperatura Corporal , Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Neuroimagem , Adulto , Idoso , Autopsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mudanças Depois da Morte
18.
Forensic Sci Int ; 270: 248-254, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27836412

RESUMO

Recently, quantitative MR sequences have started being used in post-mortem imaging. The goal of the present study was to evaluate if early acute and following age stages of myocardial infarction can be detected and discerned by quantitative 1.5T post-mortem cardiac magnetic resonance (PMCMR) based on quantitative T1, T2 and PD values. In 80 deceased individuals (25 female, 55 male), a cardiac MR quantification sequence was performed prior to cardiac dissection at autopsy in a prospective study. Focal myocardial signal alterations detected in synthetically generated MR images were MR quantified for their T1, T2 and PD values. The locations of signal alteration measurements in PMCMR were targeted at autopsy heart dissection and cardiac tissue specimens were taken for histologic examinations. Quantified signal alterations in PMCMR were correlated to their according histologic age stage of myocardial infarction. In PMCMR seventy-three focal myocardial signal alterations were detected in 49 of 80 investigated hearts. These signal alterations were diagnosed histologically as early acute (n=39), acute (n=14), subacute (n=10) and chronic (n=10) age stages of myocardial infarction. Statistical analysis revealed that based on their quantitative T1, T2 and PD values, a significant difference between all defined age groups of myocardial infarction can be determined. It can be concluded that quantitative 1.5T PMCMR quantification based on quantitative T1, T2 and PD values is feasible for characterization and differentiation of early acute and following age stages of myocardial infarction.


Assuntos
Imageamento por Ressonância Magnética , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/patologia , Miocárdio/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Temperatura Corporal , Estudos de Casos e Controles , Edema/patologia , Eosinofilia/patologia , Feminino , Fibroblastos/patologia , Patologia Legal , Granulócitos/patologia , Hemorragia/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Fatores de Tempo
19.
Forensic Sci Int ; 257: 93-97, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26284977

RESUMO

INTRODUCTION: Post-mortem cardiac MR exams present with different contraction appearances of the left ventricle in cardiac short axis images. It was hypothesized that the grade of post-mortem contraction may be related to the post-mortem interval (PMI) or cause of death and a phenomenon caused by internal rigor mortis that may give further insights in the circumstances of death. METHOD AND MATERIALS: The cardiac contraction grade was investigated in 71 post-mortem cardiac MR exams (mean age at death 52 y, range 12-89 y; 48 males, 23 females). In cardiac short axis images the left ventricular lumen volume as well as the left ventricular myocardial volume were assessed by manual segmentation. The quotient of both (LVQ) represents the grade of myocardial contraction. LVQ was correlated to the PMI, sex, age, cardiac weight, body mass and height, cause of death and pericardial tamponade when present. In cardiac causes of death a separate correlation was investigated for acute myocardial infarction cases and arrhythmic deaths. RESULTS: LVQ values ranged from 1.99 (maximum dilatation) to 42.91 (maximum contraction) with a mean of 15.13. LVQ decreased slightly with increasing PMI, however without significant correlation. Pericardial tamponade positively correlated with higher LVQ values. Variables such as sex, age, body mass and height, cardiac weight and cause of death did not correlate with LVQ values. There was no difference in LVQ values for myocardial infarction without tamponade and arrhythmic deaths. CONCLUSION: Based on the observation in our investigated cases, the phenomenon of post-mortem myocardial contraction cannot be explained by the influence of the investigated variables, except for pericardial tamponade cases. Further research addressing post-mortem myocardial contraction has to focus on other, less obvious factors, which may influence the early post-mortem phase too.


Assuntos
Imageamento por Ressonância Magnética , Miocárdio/patologia , Rigor Mortis , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Arritmias Cardíacas/patologia , Tamponamento Cardíaco/patologia , Criança , Feminino , Ventrículos do Coração/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Estudos Retrospectivos , Adulto Jovem
20.
Forensic Sci Int ; 225(1-3): 67-70, 2013 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-23021107

RESUMO

We present postmortem computed tomography (pmCT) as well as postmortem magnetic resonance (pmMR) imaging findings in a case of type II DeBakey aortic dissection with a complete rupture of the ascending aorta compared to the findings obtained at forensic autopsy. PmCT only allowed a presumptive diagnosis of aortic dissection based on an anterior mediastinal enlargement. However, at pmMR the dissection including the aortic rupture was clearly visible. Visualization was realized in an unenhanced manner without the need for postmortem angiography.


Assuntos
Aneurisma Aórtico/patologia , Dissecção Aórtica/patologia , Ruptura Aórtica/patologia , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Adulto , Dissecção Aórtica/classificação , Oclusão Coronária/patologia , Vasos Coronários/patologia , Patologia Legal/métodos , Humanos , Masculino
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