Massive bleeding from an infected pseudoaneurysm in an arteriovenous graft that resulted in death: A case report.

We report an autopsy of a death due to a ruptured infected pseudoaneurysm; a man in his 70s was found dead with massive bleeding from the shunt of his right arm. Autopsy and pathological examination revealed that the cause of death was hemorrhagic shock due to rupture of an infected pseudoaneurysm. Ruptured aneurysms and pseudoaneurysm are a complication of dialysis, and death is rare because they are treated immediately on discovery. However, these ruptures often occur in non-medical facilities and could result in death if the patient does not have knowledge of first aid. Thus, patient education is important. Approximately only half of the deaths due to massive bleeding from a shunt are autopsied. In Japan, autopsies or partial autopsies are considered necessary to determine whether a bleeding was traumatic and to prevent medical errors from being overlooked.

Postmortem changes in the eye on computed tomography images.

BACKGROUND: Ocular tension decreases with increasing postmortem interval (PMI) and eyes collapse with extreme progression of postmortem change; however, time-related changes in postmortem computed tomography (PMCT) findings have not been clarified. This study aimed to quantitatively evaluate the vitreous volume and CT values of the vitreous body to clarify time-related changes in PMCT. METHODS: We retrospectively reviewed PMCT images of the eyes of subjects who underwent autopsy at our institution between July 2023 and February 2024. They were classified into four PMI groups: PMI-1: < 1 day, PMI-2: 1-2 days, PMI-3: 3-6 days, PMI-4: ≥ 7 days. The vitreous volumes and mean CT values of the vitreous chambers were measured. Additionally, the presence of intraocular gas and crystalline lens dislocation was observed. RESULTS: The PMCT images of 131 eyes of 66 patients (41 males, 25 females) were analyzed. The mean age was 63.7 (22-99) years. The volume of the vitreous cavity was significantly decreased at PMI-3 and PMI-4, which indicated scleral depression. Intraocular gas appeared in PMI-4. Lens dislocation began at PMI-3 and was more frequently observed at PMI-4 and in the higher-temperature environment group. CONCLUSION: Ocular findings on PMCT are useful for estimating the time of death.

Postmortem contrast-enhanced computed tomography via direct large-vessel puncture.

The aim of this study was to assess the usefulness of postmortem contrast-enhanced CT (PMeCT) performed via direct large-vessel puncture when routine postmortem CT suggests a vascular lesion as the cause of death. PMeCT was performed in 9 cases (4 male, 5 female) with a mean age of 76 years (range 52-92) at the time of death. The mean time elapsed since death was 29.1 h (12.0-72.0). The location of the target vessel for puncture was determined based on the CT table position and a grid placed on the body surface. An 18-G spinal needle was advanced to the puncture site, and the needle tip was confirmed to have reached the intended blood vessel. Using negative pressure with a 20-ml syringe, the needle tip was advanced until reverse bleeding was confirmed. Diluted contrast medium was injected slowly to ensure its dispersion within the blood vessels. Following confirmation of no extravasation, additional doses of diluted contrast agent were injected in 3-4 divided doses, with CT scans obtained at each step to track the distribution of contrast agent over time. PMeCT was successful in all cases, revealing cardiac tamponade in 7 (ascending aortic dissection, n = 6; cardiac rupture, n = 1), thoracic aortic aneurysm rupture, n = 1, and iliac artery aneurysm rupture, n = 1. There were no cases of procedure-related extravasation (pseudo-lesions). When postmortem CT reveals pericardial hematoma or bleeding in the thoracic or abdominal cavity, PMeCT can identify the source of bleeding.

Estimating age at death by Hausdorff distance analyses of the fourth lumbar vertebral bodies using 3D postmortem CT images.

The existing methods for determining adult age from human skeletons are mostly qualitative. However, a shift in quantifying age-related skeletal morphology on a quantitative scale is emerging. This study describes an intuitive variable extraction technique and quantifies skeletal morphology in continuous data to understand their aging pattern. A total of 200 postmortem CT images from the deceased aged 25-99 years (130 males, 70 females) who underwent forensic death investigations were used in the study. The 3D volume of the fourth lumbar vertebral body was segmented, smoothed, and post-processed using the open-source software ITK-SNAP and MeshLab, respectively. To measure the extent of 3D shape deformity due to aging, the Hausdorff distance (HD) analysis was performed. In our context, the maximum Hausdorff distance (maxHD) was chosen as a metric, which was subsequently studied for its correlation with age at death. A strong statistically significant positive correlation (P < 0.001) between maxHD and age at death was observed in both sexes (Spearman's rho = 0.742, male; Spearman's rho = 0.729, female). In simple linear regression analyses, the regression equations obtained yielded the standard error of estimates of 12.5 years and 13.1 years for males and females, respectively. Our study demonstrated that age-related vertebral morphology could be described using the HD method. Moreover, it encourages further studies with larger sample sizes and on other population backgrounds to validate the methodology.

A novel method to estimate adult age from the lumbar vertebral body using 3D PMCT images in Japanese.

This study evaluated the age-related changes in the vertebral body using 3D Postmortem CT (PMCT) images and proposed an alternative age estimation formula. The PMCT images of 200 deceased individuals aged 25 to 99 years (126 males, 74 females) were retrospectively reviewed and included in the study. Using the open-source software ITK-SNAP and MeshLab, a 3D surface mesh of the fourth lumbar vertebral body (L4) and its convex hull models were created from the PMCT data. Using their inbuilt tools, volumes (in mm3) of the L4 surface mesh and convex hull models were subsequently computed. We derived VD, defined as the difference in volumes between the convex hull and L4 surface mesh normalized by L4 mesh volume, and VR, defined as the ratio of L4 mesh volume to convex hull volume based on individual L4. Correlation and regression analyses were performed between VD, VR, and chronological age. A statistically significant positive correlation (P < 0.001) between chronological age and VD, (rs = 0.764, males; rs = 0.725, females), and a significant negative correlation between chronological age and VR (rs = -0.764, males; rs = -0.725, females) was obtained in both sexes. The lowest standard error of the estimate was demonstrated by the VR at 11.9 years and 12.5 years for males and females, respectively. As such, their regression models to estimate adult age were Age = 248.9-2.5VR years, males; Age = 258.1-2.5VR years, females. These regression equations may be useful for estimating age in Japanese adults in forensic settings.

Forensic Medicine in South Asia: Comparison to the Developed Countries.

This study attempted to discuss the historical context and current practice of forensic medicine in South Asia. Comparisons within and between countries in South Asia, and between South Asia and the developed countries (represented by Japan and the USA) have been made to provide an insight into their distinct practice of forensic medicine. Though the formal establishment of forensic medicine in South Asia commenced at a comparable period to the developed countries, their pace of development has been considerably slow. Moreover, their ways of practice as well have evolved differently. In effect, South Asian countries follow an 'integrated service' system, whilst Japan and the USA practice 'divided service' systems to provide forensic medical services. Similarly, regarding the death investigations, most South Asian countries follow a Police-led death investigation system, whereas Japan and the USA follow a hybrid model and the Medical examiner's system of death investigation, respectively. Indeed, forensic medicine in South Asia is undeniably underdeveloped. In this paper, by highlighting the issues and challenges confronted in South Asia, key actions for prompt redressal are discussed to improve the standard of forensic medical services in South Asia.

Estimation of Postcardiac Arrest Interval Based on Atrial Cavity Density in Postmortem Computed Tomography.

BACKGROUND: Intracardiac hypostasis is frequently observed in postmortem computed tomography (PMCT) of acute deaths, and it becomes clearer as the postmortem interval increases. To determine the postcardiac arrest interval (PCAI), we evaluated densities of the right and left atria [anterior part of the right atrium (AR) and posterior part of the left atrium (PL)] using postmortem computed tomographic images. METHODS: A total of 184 patients were included in the study. Patients with return of spontaneous circulation and those with final alive confirmation time over 1 hour were excluded. We evaluated the density of AR and PL at the level of the right inferior pulmonary vein entry to the left atrium. We defined the interval between the estimated cardiac arrest time and the postmortem CT time as the PCAI. RESULTS: There was a negative correlation between AR and PCAI in 59 patients who died owing to cardiovascular disease. The regression equation (PCAI = -1.725 × AR + 132.95) was obtained based on this result. There was no correlation between PL and PCAI. CONCLUSION: The result suggests that the density of the anterior part of the right atrium decreases as postcardiac arrest interval increases in the case of cardiovascular disease. The regression equation may be used as an additional method to estimate postcardiac arrest interval.

Paravertebral compartment syndrome after exercise: a case report.

BACKGROUND: Paravertebral compartment syndrome occurring without trauma is quite rare. We report a case of compartment syndrome that occurred after spinal exercises. CASE PRESENTATION: A 23-year-old Japanese rower developed severe back pain and was unable to move 1 day after performing exercises for the spinal muscles. Initial evaluation at a nearby hospital revealed hematuria and elevated creatine phosphokinase levels. He was transferred to our hospital, where magnetic resonance imaging revealed no hematoma but confirmed edema in the paravertebral muscles. The compartment pressure measurements were elevated bilaterally. Despite his pain being severe, his creatine phosphokinase levels were expected to peak and decline; his urine output was normal; and surgery was undesirable. Therefore, we opted for conservative management. The next day, the patient's compartment pressure diminished, and his pain levels decreased to 2/10. After 5 days, he was able to walk without medication. CONCLUSIONS: We present a rare case of compartment syndrome of the paravertebral muscles with good resolution following conservative management. We hope our case findings will help avoid unnecessary surgery in cases of paravertebral compartment syndrome.