Hidemi Okuma

Heart Wall Is Thicker on Postmortem Computed Tomography Than on Ante Mortem Computed Tomography: The First Longitudinal Study

Objective To evaluate the postmortem changes of the heart wall on postmortem (PM) computed tomography (CT) in comparison with those on ante mortem CT (AMCT), and in comparison with the pathological findings, obtained in the same patients. Materials and Methods We studied 57 consecutive patients who had undergone AMCT, PMCT, and pathological autopsy in our tertiary care hospital between April 2009 and December 2010. PMCT was performed within 20 hours after death, followed by pathological autopsy. The cardiac chambers were measured at five sites on both AMCT and PMCT by two board-certified radiologists who were not provided with clinical information. The differences in heart wall thickness between AMCT with and without contrast medium, between AMCT and PMCT, and between PMCT and pathological anatomy were evaluated statistically. Confounding factors of postmortem change such as gender, presence of arteriosclerosis, the organ related to cause of death, age, and elapsed time since death were examined statistically. Results No significant differences were observed on AMCT in comparison of contrasted and non-contrasted images. The heart wall was significantly thicker on PMCT than on AMCT (p < 0.0001) at all five measurement sites. The heart wall was significantly thicker on PMCT than on pathology specimens when measured in accordance with pathological standard mensuration. However, no significant difference was observed between PMCT measurements and those of pathology specimens at any site when the papillary muscles and epicardial fat were included. No significant association was found between postmortem change in heart wall thickness and gender, presence of arteriosclerosis, the organ related to cause of death, age, or elapsed time since death. Conclusion This is the first longitudinal study to confirm greater thickness of heart wall on postmortem images compared with ante mortem images, in the same patients. Furthermore, the postmortem changes on CT were supported by the pathological findings.

Brain Swelling and Loss of Gray and White Matter Differentiation in Human Postmortem Cases by Computed Tomography

The purpose of this study was to evaluate the brain by postmortem computed tomography (PMCT) versus antemortem computed tomography (AMCT) using brains from the same patients. We studied 36 nontraumatic subjects who underwent AMCT, PMCT, and pathological autopsy in our hospital between April 2009 and December 2013. PMCT was performed within 20 h after death, followed by pathological autopsy including the brain. Autopsy confirmed the absence of intracranial disorders that might be related to the cause of death or might affect measurements in our study. Width of the third ventricle, width of the central sulcus, and attenuation in gray matter (GM) and white matter (WM) from the same area of the basal ganglia, centrum semiovale, and high convexity were statistically compared between AMCT and PMCT. Both the width of the third ventricle and the central sulcus were significantly shorter in PMCT than in AMCT (P < 0.0001). GM attenuation increased after death at the level of the centrum semiovale and high convexity, but the differences were not statistically significant considering the differences in attenuation among the different computed tomography scanners. WM attenuation significantly increased after death at all levels (P<0.0001). The differences were larger than the differences in scanners. GM/WM ratio of attenuation was significantly lower by PMCT than by AMCT at all levels (P<0.0001). PMCT showed an increase in WM attenuation, loss of GM–WM differentiation, and brain swelling, evidenced by a decrease in the size of ventricles and sulci.

Common Postmortem Computed Tomography Findings Following Atraumatic Death: Differentiation between Normal Postmortem Changes and Pathologic Lesions

Computed tomography (CT) is widely used in postmortem investigations as an adjunct to the traditional autopsy in forensic medicine. To date, several studies have described postmortem CT findings as being caused by normal postmortem changes. However, on interpretation, postmortem CT findings that are seemingly due to normal postmortem changes initially, may not have been mere postmortem artifacts. In this pictorial essay, we describe the common postmortem CT findings in cases of atraumatic in-hospital death and describe the diagnostic pitfalls of normal postmortem changes that can mimic real pathologic lesions.

Fluid in the airway of nontraumatic death on postmortem computed tomography: relationship with pleural effusion and postmortem elapsed time.

AbstractTo evaluate radiographic features of endotracheal/endobronchial fluid in the airway (FA) observed on postmortem computed tomography (PMCT). We studied 164 subjects who died at our hospital between April 2009 and September 2012. Fluid in the airway was considered positive when fluid was identified in the lumen of 1 of the 2 main bronchi in continuity with a segmental bronchus. Pleural effusion and atelectasis/consolidation of the lung lower lobes were also evaluated. Fluid in the airway was observed in 60 (71%) of 84 subjects with unilateral or bilateral pleural effusion, and in 44 (55%) of 80 subjects without pleural effusion (P = 0.029). Of the latter, 41 (93%) had atelectasis/consolidation of the lower lung lobes. Among subjects without pleural effusion, average times after death to PMCT of subjects with and without FA were 501 and 314 minutes, respectively (P = 0.01). Time-course analysis showed that cases with FA on PMCT largely correlated with time after death (R2 = 0.7966). Fluid in the airway is frequently observed on PMCT in subjects with pleural effusion or atelectasis/consolidation of the lung. No FA in subjects without pleural effusion correlated to shorter times after death. In addition, FA frequency on PMCT increased over time after death.

Comparison of Attenuation of Striated Muscle between Postmortem and Antemortem Computed Tomography: Results of a Longitudinal Study

Objective We evaluated the postmortem changes of striated muscle by comparing computed tomography (CT) images obtained postmortem and antemortem in the same patients. Materials and Methods We studied 33 consecutive patients who underwent antemortem CT, postmortem CT, and pathological autopsy in our tertiary care hospital between April 2009 and December 2010. Postmortem CT was performed within 20 h after death and was followed by pathological autopsy. Pathological autopsy confirmed the absence of muscular diseases such as amyotrophic lateral sclerosis, muscular dystrophy, myositis, and myasthenia, in all of the patients. The CT attenuation values of four cardiac muscle sites (anterior wall of the left ventricle, left ventricular free wall, posterior wall of the left ventricle, and the ventricular septum) and two skeletal muscle sites (the pectoralis major muscle and the erector spinae muscle) were compared between antemortem and postmortem CT using paired t test. Results Striated muscle had significantly greater attenuation on postmortem CT than on antemortem CT (P<0.001) in all six tissue sites. No significant association was found between postmortem change in the CT attenuation of striated muscle and gender, age, or elapsed time since death. Conclusion This is the first longitudinal study to show hyperattenuation of striated muscle on postmortem CT images compared with antemortem CT images in the same patients.

Laminar crystal deposition in large vessels in a patient with crystalglobulinemia

Crystalglobulinemia is an extremely rare complication of monoclonal gammopathy and is characterized by crystal thrombi within systemic organs. We herein report the first described case of crystalglobulinemia accompanied by laminar crystal deposition in the large vessels. A 44‐year‐old man presented with a history of numbness, pain, and swelling of the left leg in addition to visual impairment. Renal and skin biopsies revealed crystal thrombi within the capillary lumens. The patient was finally diagnosed with crystalglobulinemia associated with multiple myeloma. He was treated with hemodialysis and chemotherapy but died of the disease 15 months after admission. Autopsy demonstrated a huge amount of crystal deposition in the subintimal layer of the vascular wall throughout the thoracic to abdominal aorta. The characteristic deposition extended to the iliac arteries, common carotid arteries, and subclavian arteries but did not affect the bilateral renal arteries. Antemortem computed tomography demonstrated higher intensity in the wall of the abdominal aorta but not in the walls of the renal arteries, suggesting that a finding of high intensity on computed tomography could be a clinical marker of systemic crystal deposition.

Comparison of the cardiothoracic ratio between postmortem and antemortem computed tomography

As postmortem imaging has gained prominence as a supplement to traditional autopsy, it is important to understand the normal postmortem changes to enable the accurate evaluation of postmortem imaging. No studies have evaluated the postmortem changes in cardiothoracic ratio (CTR) compared with antemortem images in the same subjects. We studied 147 consecutive subjects who underwent antemortem and postmortem CT, and autopsy. Postmortem CT was performed <23h after death and was followed by autopsy. The subjects were divided into three groups: normal heart, old myocardial infarction, and CPR-treated hearts. CTR was compared between antemortem and postmortem CT using paired t tests, which revealed that the CTR was greater on postmortem CT than on antemortem CT in all groups (mean CTR: 0.53±0.06vs. 0.50±0.06, respectively; P<0.01). Sex, age, time elapsed since death, and the causes of death were examined as potential confounding factors for the postmortem changes in CTR, but no significant associations were found. Receiver-operating characteristic (ROC) curves were used to determine CTR values for cardiomegaly, which was defined according to the autopsy weight of the heart. The area under the ROC curve was 0.71 (95% confidence interval 0.63-0.79). The CTR threshold of 0.54 identified cardiomegaly with the greatest accuracy, compared with the general threshold of 0.50. In conclusion, the CT-determined CTR increases after death, irrespective of the hearts condition. We should be cautious of overdiagnosis of cardiomegaly on postmortem CT, and new criteria for interpreting cardiomegaly on postmortem CTR are needed.

The pseudo-SAH sign: an imaging pitfall in postmortem computed tomography

Postmortem computed tomography (PMCT) of the brain has an important role in detection of subarachnoid hemorrhage (SAH), which has a high mortality rate. However, a phenomenon known as “pseudo-SAH,” or high-attenuation areas along the cisterns mimicking SAH, may be seen on CT. The aim of this study was to evaluate the diagnostic accuracy of brain PMCT for SAH and to identify the characteristics of pseudo-SAH. Findings on PMCT (sulcal effacement, asymmetry, maximum thickness of SAH signs, presence of acute/subacute intraventricular/intraparenchymal hemorrhage) and clinical history (left ventricular assist device [LVAD] implantation, anticoagulation therapy/coagulation disorder, global ischemia) were compared between subjects with true SAH and those with pseudo-SAH. Twenty eight of 128 enrolled subjects had positive signs of SAH on PMCT, 20 (71.4%) had SAH on autopsy, and 8 (28.6%) did not. The sensitivity, specificity, positive predictive value, and negative predictive value of SAH signs seen on PMCT were 95.2, 94.6, 71.4, and 99.3%, respectively. Asymmetry of SAH signs and acute/subacute intraventricular and intraparenchymal hemorrhage were significantly more common in true SAH cases than in pseudo-SAH cases. The maximum thickness of SAH signs was significantly greater in true SAH cases. A history of LVAD implantation, anticoagulation therapy, and/or a coagulation disorder were more common in true SAH cases but not significantly so. A history of global ischemia was significantly more common in pseudo-SAH cases. If signs of SAH are observed on PMCT, it is important to look for other signs on PMCT and carefully review the clinical history to avoid a diagnostic error.

Development of pancreatic cancer is predictable well in advance using contrast-enhanced CT: a case–cohort study

AbstractObjectivesTo investigate the radiological findings prognostic for the development of pancreatic adenocarcinoma in a cohort of patients with hepatocellular carcinoma, using multiphasic computed tomography (CT).MethodsA case–cohort study performed in a single university hospital. A database of patients who received hepatocellular carcinoma (HCC) treatment and trimonthly follow-up with four-phase dynamic CT was used (n = 1848). The cohort group was randomly extracted from the database (n = 103). The case group comprised nine patients from the database who developed pancreatic adenocarcinoma. The radiological findings were assessed during follow-up (average, 32 months).ResultsThe incidence of pancreatic mass, inhomogeneous parenchyma, loss of fatty marbling and main pancreatic duct dilatation gradually increased from 4 to 13 months before the diagnosis of pancreatic adenocarcinoma. There was a significantly higher incidence of pancreatic mass, inhomogeneous parenchyma and loss of fatty marbling on CT at baseline (average, 34 months before diagnosis) in the case group compared with the cohort group (P values < 0.01) and those findings at baseline were revealed as prognostic factors for pancreatic carcinogenesis, respectively (log-rank test, P values < 0.001).ConclusionsSeveral radiological findings observed on multiphasic CT can assist in predicting pancreatic carcinogenesis well in advance.Key points• Pancreatic findings in multiphasic CT help predict development of pancreatic adenocarcinoma. • Key findings are mass, inhomogeneous parenchyma and loss of fatty marbling. • Those findings were observed 34 months before confirmed diagnosis of adenocarcinoma. • Those findings were prognostic factors for pancreatic carcinogenesis.