Postmortem Magnetic Resonance Research Articles

Amyloid Angiopathy in Brain Hemorrhage: A Postmortem Neuropathological-Magnetic Resonance Imaging Study

Background: Risk factors for intracerebral hemorrhage (ICH) include hypertension and cerebral amyloid angiopathy (CAA). The objective of this study was to determine the autopsy prevalence of CAA and the potential overlap with other risk factors among patients who died from ICH and also the correlation of CAA with cerebral microbleeds. Methods: We analyzed 81 consecutive autopsy brains from patients with ICH. Staining for CAA detection was performed. We used an age- and sex-matched control group of routine brain autopsies of nonneurological patients to determine the frequencies of CAA and hypertension. Postmortem 3D T2-weighted gradient-echo magnetic resonance imaging (MRI) with a 1.5-T magnet was performed in 11 brains with ICH (5 with CAA and 6 without) and histological correlation was performed when microbleeds were detected. Results: Hypertension and CAA were found in 69.1 and 24.7% of cases respectively. Among patients with CAA, 65.0% also had hypertension. The prevalence of CAA was similar among non-hypertensive cases and controls (33.3 and 23.1%; p = 0.54), whereas a significant difference was found between hypertensive cases vs. controls (28.9% vs. 0; p = 0.01). MRI documented 48 microbleeds and all 5 brains with CAA had ≥1 microbleed, compared to 3/6 brains without CAA. Among 48 microbleeds on MRI, 45 corresponded histologically to microbleeds surrounding microvessels (23 <200 µm in diameter, 19 between 200 µm and 2 mm, 3 were hemosiderin granules). Conclusions: Both hypertension and CAA frequently coexist in patients with ICH. MRI-detected microbleeds, proven by histological analysis, were twice as common in patients with CAA as in those with hypertensive ICH.

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

The autopsy rate worldwide is alarmingly low (0-15%). Mortality statistics are important, and it is, therefore, essential to perform autopsies in a sufficient proportion of deaths. The imaging autopsy, non-invasive, or minimally invasive autopsy (MIA) can be used as an alternative to the conventional autopsy in an attempt to improve postmortem diagnostics by increasing the number of postmortem procedures. The aim of this study was to determine the diagnostic accuracy of postmortem magnetic resonance imaging (MRI), computed tomography (CT), and CT-guided biopsy for the detection of acute and chronic myocardial ischaemia. We included 100 consecutive adult patients who died in hospital, and for whom next-of-kin gave permission to perform both conventional autopsy and MIA. The MIA consists of unenhanced total-body MRI and CT followed by CT-guided biopsies. Conventional autopsy was used as reference standard. We calculated sensitivity and specificity and receiver operating characteristics curves for CT and MRI as the stand-alone test or combined with biopsy for detection of acute and chronic myocardial infarction (MI). Sensitivity and specificity of MRI with biopsies for acute MI was 0.97 and 0.95, respectively and 0.90 and 0.75, respectively for chronic MI. MRI without biopsies showed a high specificity (acute: 0.92; chronic: 1.00), but low sensitivity (acute: 0.50; chronic: 0.35). CT (total Agatston calcium score) had a good diagnostic value for chronic MI [area under curve (AUC) 0.74, 95% confidence interval (CI) 0.64-0.84], but not for acute MI (AUC 0.60, 95% CI 0.48-0.72). We found that the combination of MRI with biopsies had high sensitivity and specificity for the detection of acute and chronic myocardial ischaemia.

Improved Visualization of Cortical Lesions in Multiple Sclerosis Using 7T MP2RAGE.

Cortical lesions are common and often extensive in multiple sclerosis but are difficult to visualize by MRI, leaving important questions about their clinical implications and response to therapy unanswered. Our aim was to determine whether cortical lesions are better visualized using magnetization prepared 2 rapid acquisition gradient echoes (MP2RAGE) than T2*-weighted imaging on 7T MR imaging. Brain MR imaging using T1-weighted MP2RAGE at 500-μm isotropic resolution, T2*-weighted gradient-echo, and T2*-weighted segmented echo-planar imaging sequences were collected for 13 patients with MS and 5 age-matched neurologically healthy controls on a 7T research system. One MS case underwent postmortem MR imaging including gradient-echo and MP2RAGE sequences, after which cortical lesions seen on MR imaging were assessed with immunohistochemistry. MP2RAGE detected 203 cortical lesions (median, 16 lesions/case; interquartile range, 15), compared to 92 with T2*gradient-echo (median, 7; interquartile range, 8; P < .001) and 81 with T2*EPI (median, 7; interquartile range, 5; P < .001). This increase in lesion number detected on MP2RAGE versus T2* was observed for juxtacortical, leukocortical, and intracortical lesions. Forty-three percent of all cortical lesions were identified only on MP2RAGE. White matter lesion volume correlated with total juxtacortical (r = 0.86, P < .001) and leukocortical lesion volume (r = 0.70, P < .01) but not intracortical lesion volume, suggesting that pathophysiology may differ by lesion type. Of 4 suspected lesions seen on postmortem imaging, 3 were found to be true cortical lesions while 1 represented postmortem tissue damage. A combination of MP2RAGE and T2*-weighted imaging at 7T improved detection of cortical lesions and should enable longitudinal studies to elucidate their spatiotemporal dynamics and clinical implications.

Post-mortem MR angiography: quantitative investigation and intravascular retention of perfusates in ex situ porcine hearts

As the implementation of minimally invasive imaging techniques in both forensic and pathological practice increases, research in this area focuses on addressing recognised diagnostic weaknesses of current approaches. Assessment of sudden cardiac death (SCD) can be considered one such area in which post-mortem imaging still shows diagnostic weaknesses. We hypothesise that magnetic resonance imaging (MRI) with an angiographic adjunct may improve the visualisation and interpretation of cardiac pathologies in a post-mortem setting. To systematically investigate this hypothesis, selected perfusates (paraffin oil, Gadovist®;-doped physiological solution and polyethylene glycol (PEG)) were injected into the left anterior descending (LAD) artery of ex situ porcine hearts to assess the visualisation of perfusates in MRI as well as their intravascular retention over 12 h. Morphological images were acquired and quantitative T1 maps were generated from inversion recovery data. Visualisation of vascular structure and image quality were assessed using signal-to-noise and contrast-to-noise ratios. Intravascular retention was assessed both visually and statistically using a volume of interest (VOI) approach to analyse significant changes in signal intensity in and around the filled LAD artery, as well as changes in the longitudinal relaxation time (T1) in adjacent myocardium. In addition to presenting possible mechanisms explaining perfusate extravasation given the increased permeability of post-mortem vessels, the potential diagnostic consequences of this phenomenon and the importance of contrast stability and extended intravascular retention are discussed. In light of our findings and these considerations, paraffin oil emerged as the preferred perfusate for use in post-mortem MR angiography.

Utility of Postmortem CT and MR in the Diagnosis of Unexpected Death

Background: We have previously demonstrated that postmortem computed tomography (CT) and magnetic resonance (MR) can accurately identify certain causes of death in those <40 years versus conventional autopsy.

Chapter 23 - Postmortem magnetic resonance imaging

This chapter provides a brief overview of studies that combine postmortem magnetic resonance imaging (MRI) and histopathology. We touch upon the logistics of setting up a protocol that limits unwanted postmortem delays and explain how combining postmortem MRI and histopathology can elucidate the histologic substrate of signal changes that appear on MRI. This is demonstrated by exemplary studies in multiple sclerosis, and includes various histopathologic techniques and a wide range of conventional and advanced MRI sequences at various field strengths. We cover topics such as how to visualize white-matter pathology and repair with conventional and advanced MRI sequences, describe the history of visualizing pathology of the gray matter (with newly developed MRI and immunohistopathology techniques), and how advanced methods have aided research in other neurologic diseases. We conclude with several suggestions for future development, such as bridging the gap between postmortem and in vivo research and the importance of collecting non-neurological control tissue.

Risk factors and classification of stillbirth in a Middle Eastern population: a retrospective study.

To estimate the incidence of stillbirth, explore the associated maternal and fetal factors and to evaluate the most appropriate classification of stillbirth for a multiethnic population. This is a retrospective population-based study of stillbirth in a large tertiary unit. Data of each stillbirth with a gestational age >/=24 weeks in the year 2015 were collected from electronic medical records and analyzed. The stillbirth rate for our multiethnic population is 7.81 per 1000 births. Maternal medical factors comprised 52.4% in which the rates of hypertensive disorders, diabetes and other medical disorders were 22.5%, 20.8% and 8.3%, respectively. The most common fetal factor was intrauterine growth restriction (IUGR) (22.5%) followed by congenital anomalies (21.6%). All cases were categorized using the Wigglesworth, Aberdeen, Tulip, ReCoDe and International Classification of Diseases-perinatal mortality (ICD-PM) classifications and the rates of unclassified stillbirths were 59.2%, 46.6%, 16.6%, 11.6% and 7.5%, respectively. An autopsy was performed in 9.1% of cases reflecting local religious and cultural sensitivities. This study highlighted the modifiable risk factors among the Middle Eastern population. The most appropriate classification was the ICD-PM. The low rates of autopsy prevented a detailed evaluation of stillbirths, therefore it is suggested that a minimally invasive autopsy [postmortem magnetic resonance imaging (MRI)] may improve the quality of care.

Post-mortem magnetic resonance (PMMR) imaging of fetal central nervous system: A systematic review

Abstract In this systematic review the diagnostic capabilities of post-mortem MR (PMMR) concerning brain and spinal cord abnormalities compared to traditional autopsy were analyzed. A computerized online search of scientific articles was performed using Medline (PubMed) databases in June 2016 to identify all studies comparing PMMR with conventional autopsy in detecting fetal central nervous system alterations. Titles and abstracts were screened based on these exclusion criteria: no paediatric cases, neuroradiological alterations not reported, studies not in English, case reports and reviews, less than 10 subjects analyzed, PMMR performed on MR Units with magnetic field different from 1,5 or 3 T. Full texts of potentially relevant publications were read. Only articles with a clearly stated comparison between PMMR and autopsy results were included. 467 abstracts were identified; 14 papers met the inclusion criteria; data from 8 studies were extracted (467 cases). Of the 8 papers examined all regarded fetuses; only one analyzed also children Based on these results, PMMR might be considered a valid support/substitute to traditional autopsy for studying fetal central nervous system.

Total-body CT and MR features of postmortem change in in-hospital deaths.

ObjectivesTo evaluate the frequency of total-body CT and MR features of postmortem change in in-hospital deaths.Materials and methodsIn this prospective blinded cross-sectional study, in-hospital deceased adult patients underwent total-body postmortem CT and MR followed by image-guided biopsies. The presence of PMCT and PMMR features related to postmortem change was scored retrospectively and correlated with postmortem time interval, post-resuscitation status and intensive care unit (ICU) admittance.ResultsIntravascular air, pleural effusion, periportal edema, and distended intestines occurred more frequently in patients who were resuscitated compared to those who were not. Postmortem clotting was seen less often in resuscitated patients (p = 0.002). Distended intestines and loss of grey-white matter differentiation in the brain showed a significant correlation with postmortem time interval (p = 0.001, p<0.001). Hyperdense cerebral vessels, intravenous clotting, subcutaneous edema, fluid in the abdomen and internal livores of the liver were seen more in ICU patients. Longer postmortem time interval led to a significant increase in decomposition related changes (p = 0.026).ConclusionsThere is a wide variety of imaging features of postmortem change in in-hospital deaths. These imaging features vary among clinical conditions, increase with longer postmortem time interval and must be distinguished from pathologic changes.

Postmortem MR diffusion-weighted imaging of the liver: time-behavior of the hepatic apparent diffusion coefficient in the early death interval.

The objective of this study is to assess postmortem changes of the hepatic apparent diffusion coefficient (ADC) at multiple time points in the time interval of 16hours postmortem in comparison to in vivo controls and to literature data. Hepatic diffusion-weighted imaging (DWI) was repeatedly performed at 1.5Tesla (b values 50, 400, and 800s/mm2) in 2-hourly steps within 16hours postmortem in 19 cases (male to female 13:6, mean age 68.5±12.2years) and 5 in vivo controls. The core body temperature was measured rectally prior to every scan. Mean ADC values were calculated from regions of interest (ROIs) and compared to in vivo healthy controls and to literature data of normal liver parenchyma. Spearman rank correlation and Levenberg-Marquardt algorithm were used to assess a relationship between postmortem core body temperature and ADC values. Mean hepatic ADC values were significantly lower in postmortem cases than in in vivo controls (52.0±15.0·10-5mm2/s vs. 111.0±15.7·10-5mm2/s, p<0.0001). The ex vivo liver ADC correlated inversely to calculated liver temperature (-3.5±0.8)·10-5mm2/s/°C, r=-0.44, p<0.0001. At low calculated liver temperature (<30°C), the ADC described an average increase of (22±10)·10-5mm2/s/°C. Hepatic ADC values show a characteristic change in the immediate 16hours postmortem, which is influenced by the postmortem liver temperature change. With the knowledge of characteristic postmortem liver changes, diffusion-weighted imaging could be added to conventional postmortem MRI for virtual autopsy.

EP22.18: Factors affecting the condition of the fetal brain on postmortem MRI

Fetal postmortem magnetic resonance imaging (MRI) of the brain may result in images of varying quality, which may limit the assessment of the fetal brain. Aim of the present study was to identify factors which may have an effect on the condition of the fetal brain at postmortem MRI. Retrospective analysis of 118 fetal postmortem MRI examinations performed on a 3 Tesla unit for clinical purposes. The fetuses (13-42 gestational weeks) were divided into three groups: (1) preterm delivery and induction of labour, (2) feticide and (3) intrauterine fetal death (IUFD). The condition of the fetal brain was visually assessed with respect to soft tissue decomposition and correlated with the way the fetus died and the time elapsed between fetal death and MRI. Different degrees of postmortem changes were found in each of the three groups. Excellent quality was found in group 1, good results in group 2, and poor quality was observed in group 3. The mean time between fetal death and postmortem MRI was 14.7 hours in group 1 (median 12.2 h), 157.1 h in group 2 (median: 58.7h), and 76.8 h in group 3 (median: 68.1), respectively. The quality of fetal postmortem MRI highly depends on the fetus' condition. The time elapsed between fetal demise and MRI and the way of death have a significant impact on the state of preservation of the fetal brain, and thus on image quality. The shorter the time between death and MRI is, the better the resulting image quality.

P09.01: Otocephaly‐agnathia, proboscis and holoprosencephaly diagnosed in a fetus with Trisomy 18 using three‐dimensional ultrasound and postmortem magnetic resonance imaging

P09.01: Otocephaly‐agnathia, proboscis and holoprosencephaly diagnosed in a fetus with Trisomy 18 using three‐dimensional ultrasound and postmortem magnetic resonance imaging

Fast three-dimensional whole-body post-mortem magnetic resonance angiography

Abstract Purpose The goal of this study was to perform whole-body post-mortem magnetic resonance (PMMR) angiography with imaging quality comparable to that of post-mortem computed tomography (PMCT) angiography. Methods After contrast medium injection into the arterial and venous vascular system of seven human corpses PMMR was performed using a fast three-dimensional T1 weighted spoiled gradient-echo sequence, followed by PMCT imaging. The contrast medium volumes inside the descending aorta and inside the inferior vena cava were measured both on PMMR and on PMCT images by means of image segmentation. Visualization quality of arterial and venous vessels as a function of contrast filling was scored according to a four-point scale and compared using the paired Wilcoxon signed rank test. Results The contrast medium volume in the descending aorta decreased 12% on average from PMMR to PMCT angiography, while the contrast medium volume in the inferior vena cava increased by 11% on average. A total of 410 vessels were analyzed. Scores for all vessels were statistically significantly smaller for the PMMR angiography when compared to PMCT angiography (p = 0.01). No statistically significant differences were found for the subgroups of large vessels (p = 0.21), for the head and neck (p = 0.16) or the abdomen (p = 0.83) as well as for the thorax when the coronary arteries were left out (p = 0.23). Conclusions This study demonstrates that immediate image acquisition after contrast injection and rapid 3D whole-body image acquisition offers good image quality in PMMR angiography with a vascular contrast comparable to PMCT angiography.

High resolution post-mortem MRI of non-fixed in situ foetal brain in the second trimester of gestation: Normal foetal brain development.

To describe normal foetal brain development with high resolution post-mortem MRI (PMMRI) of non-fixed foetal brains. We retrospectively collected PMMRIs of foetuses without intracranial abnormalities and chromosomal aberrations studied after a termination of pregnancy due to extracranial abnormalities or after a spontaneous intrauterine death. PMMRIs were performed on a 3-T scanner without any fixation and without removing the brain from the skull. All PMMRIs were evaluated in consensus by two neuroradiologists. Our analysis included ten PMMRIs (median gestational age (GA): 21weeks; range: 17-28weeks). At 19 and 20weeks of GA, the corticospinal tracts are recognisable in the medulla oblongata, becoming less visible from 21weeks. Prior to 20weeks the posterior limb of the internal capsule (PLIC) is more hypointense than surrounding deep grey nuclei; starting from 21weeks the PLIC becomes isointense, and is hyperintense at 28weeks. From 19-22weeks, the cerebral hemispheres show transient layers: marginal zone, cortical plate, subplate, and intermediate, subventricular and germinal zones. PMMRI of non-fixed in situ foetal brains preserves the natural tissue contrast and skull integrity. We assessed foetal brain development in a small cohort of foetuses, focusing on 19-22 weeks of gestation. • Post-mortem magnetic resonance imaging (PMMRI) of non-fixed head is feasible. • PMMRI of unfixed in situ foetal brains preserves the natural tissue contrast. • PMMRI provide a good depiction of the normal foetal brain development. • PMMRI of unfixed in situ foetal brains preserves the skull integrity. • PMMRI pattern of foetal brain development at early gestational age is described.

The diagnostic value of forensic imaging in fatal gunshot incidents: A review of literature

Abstract 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.

Early time-related course of image findings in postmortem MRI: Typical findings and observer agreement in a porcine model

To assess early time-related image findings in postmortem magnetic resonance imaging (MRI) and to evaluate observer agreement in a porcine model. Three pigs were examined by MRI at 15 different time points in the first 36h after death. Two observers independently recorded the postmortem interval (PMI) to the appearance of fluid collection (pleural space, interlobar and interlobular pulmonary fissures and hepatic interlobar fissures), gas accumulation (intrahepatic and intracardial) and blood clotting (aorta and intrahepatic venous vessels). Cohen's Kappa statistics and intraclass correlation coefficient (ICC) were used to evaluate intra- and interobserver agreement. Intrahepatic gas was evident after 12, 17 and 30h. Also, intracardiac gas was present in all animals. However, no chronological appearance has been observed. Blood clotting in the hepatic vein was observed within 3min, aortic clotting with a delay of 2-12h after death. Interlobular pulmonary fluid (median PMI: 2h, range 2-2h), pleural effusion (median PMI: 10.5h, range 9-12h) and hepatic interlobar fissure fluid (median PMI: 11.5h, range 11-12h) displayed a chronological appearance pattern. Qualitative and quantitative detection of most postmortem findings showed excellent intra- and interobserver agreement with Kappa values>0.8 or ICC>0.75. Pulmonary and hepatic fissural fluid collection as well as intravasal gas accumulation are early time-related image findings in postmortem MRI. The chronological appearance of these findings can be assessed with excellent observer agreement in a porcine model.

Myocardial relaxation times measured from postmortem magnetic resonance imaging in adult humans

Abstract Purpose To measure T 1 , T 2 , T 2 * , and ADC values of myocardium with postmortem magnetic resonance (PMMR) imaging in adult humans at 1.5T and to investigate postmortem changes in the heart. Materials and Methods We performed myocardial PMMR imaging on 32 deceased adults (19 men, 13 women; mean age, 49.2 years) whose deaths were for reasons other than cardiac injury or disease. Before imaging, the bodies were kept in cold storage at 4°C (mean rectal temperature, 17.3°C), and PMMR imaging data were obtained at a mean of 31.1h after the estimated time of death. We measured T 1 , T 2 , T 2 * , and ADC values in the short axis of the heart at four sites (the anterior, lateral, and inferior walls of the left ventricle, and interventricular septum at the middle level of the left ventricle). For 4 sites, homogeneity of variance was assessed by the Bartlett test. Parametric comparisons used analysis of variance (ANOVA). The association of rectal temperature, postmortem interval (time elapsed before MRI after the estimated time of death), and age in T 1 , T 2 , T 2 *, and ADC values was measured by multiple regression analysis. Results We did not observe differences in the dispersion and central tendency in 4 parameters （T 1 , T 2 , T 2 *, and ADC values） at the four measured sites. The average T 1 , T 2 , T 2 * , and ADC values were 934 ± 220ms, 69 ± 12ms, 34 ± 9ms, and 0.198 ± 0.053 × 10 −3 mm 2 /s, respectively. T 1 values were influenced by age and rectal temperature, respectively (multivariable-adjusted partial Pearson correlations ( r ) = −0.363; p = 0.045 and r = 0.609; p 2 values were influenced by age and postmortem interval, respectively ( r = 0.457; p = 0.010 and r = −0.615; p Conclusion Reduction in rectal temperature, decomposition after death and age are conjointly related with myocardial relaxation times on PMMR imaging.

Spatiotemporal Relationship of Brain Pathways during Human Fetal Development Using High-Angular Resolution Diffusion MR Imaging and Histology.

In this study, we aimed to identify major fiber pathways and their spatiotemporal relationships within transient fetal zones in the human fetal brain by comparing postmortem high-angular resolution diffusion MR imaging (HARDI) in combination with deterministic streamline tractography and histology. Diffusion weighted imaging was performed on postmortem human fetal brains [N = 9, age = 18–34 post-conceptual weeks (PCW)] that were grossly normal with no pathologic abnormalities. After HARDI was performed, the fibers were reconstructed using Q-ball algorithm and deterministic streamline tractography. The position of major fiber pathways within transient fetal zones was identified both on diffusion weighted images and on histological sections. Our major findings include: (1) the development of massive projection fibers by 18 PCW, as compared to most association fibers (with the exception of limbic fibers) which have only begun to emerge, (2) the characteristic laminar distribution and sagittal plane geometry of reconstructed fibers throughout development, (3) the protracted prenatal development shown of the corpus collosum and its' associated fibers, as well as the association fibers, and (4) the predomination of radial coherence in the telencephalon (i.e., majority of streamlines in the telencephalic wall were radially oriented) during early prenatal period (24 PCW). In conclusion, correlation between histology and HARDI (in combination with Q-ball reconstruction and deterministic streamline tractography) allowed us to detect sequential development of fiber systems (projection, callosal, and association), their spatial relations with transient fetal zones, and their geometric properties.

Temperature-corrected post-mortem 1.5 T MRI quantification of non-pathologic upper abdominal organs

The present study aimed to evaluate if simultaneous temperature-corrected T1, T2, and proton density (PD) 1.5T 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. QPMMRI was performed on 80 corpses (25 females, 55 males; mean age 56.2years, 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. 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. Temperature-corrected 1.5T 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.

Temperature-corrected postmortem 3-T MR quantification of histopathological early acute and chronic myocardial infarction: a feasibility study.

The goal of the present study was to evaluate if quantitative postmortem cardiac 3-T magnetic resonance (QPMCMR) T1 and T2 relaxation times and proton density values of histopathological early acute and chronic myocardial infarction differ to the quantitative values of non-pathologic myocardium and other histopathological age stages of myocardial infarction with regard to varying corpse temperatures. In 60 forensic corpses (25 female, 35 male), a cardiac 3-T MR quantification sequence was performed prior to autopsy and cardiac dissection. Core body temperature was assessed during MR examinations. Focal myocardial signal alterations in synthetically generated MR images were measured for their T1, T2, and proton density (PD) values. Locations of signal alteration measurements in PMCMR were targeted at heart dissection, and myocardial tissue specimens were taken for histologic examinations. Quantified signal alterations in QPMCMR were correlated to their according histologic age stage of myocardial infarction, and quantitative values were corrected for a temperature of 37°C. In QPMCMR, 49 myocardial signal alterations were detected in 43 of 60 investigated hearts. Signal alterations were diagnosed histologically as early acute (n=16), acute (n=10), acute with hemorrhagic component (n=9), subacute (n=3), and chronic (n=11) myocardial infarction. Statistical analysis revealed that based on their temperature-corrected quantitative T1, T2, and PD values, a significant difference between early acute, acute, and chronic myocardial infarction can be determined. It can be concluded that quantitative 3-T postmortem cardiac MR based on temperature-corrected T1, T2, and PD values may be feasible for pre-autopsy diagnosis of histopathological early acute, acute, and chronic myocardial infarction, which needs to be confirmed histologically.