The common pattern of postmortem changes on whole body CT scans

Post-mortem radiology in fetal and neonatal death: the diagnostic value of post-mortem MRI versus autopsy regarding non-cardiac thoracic and abdominal abnormalities

AIM

To compare the diagnostic value and accuracy of post-mortem magnetic resonance imaging (PMMRI) and autopsy for non-cardiac thoracic and abdominal abnormalities in fetal death.

MATERIALS AND METHODS

This single-institution retrospective study included all consecutive cases of fetal and perinatal death between January 2015 and December 2021 for which PMMRI followed by autopsy was conducted. These cases comprised fetuses at >18 weeks of gestation and preterm and term neonates who lived for <24 h. All PMMRI and autopsy reports were re-assessed and scored for seven non-cardiac thoracic and 52 abdominal abnormalities, and concordance between autopsy and PMMRI findings was determined as the primary outcome.

RESULTS

Eighty cases were included in this study. Fetal loss was caused by termination of pregnancy in 80% of cases. Further, the mean gestational age was 166 days (23 weeks and 5 days, range 126-283 days). The concordance between PMMRI and autopsy for non-cardiac thoracic and abdominal abnormalities was 83.1% (95% confidence interval [CI] 71.3-83.3) and 76.3% (95% CI 65.8-84.2%), respectively, with a substantial and moderate strength of agreement (Cohen's kappa = 0.63 and 0.51 respectively).

CONCLUSION

PMMRI exhibited good overall diagnostic value for non-cardiac thoracic and abdominal abnormalities, specifically large structural abnormalities. PMMRI may offer parents and physicians a valuable addition to autopsy for the detection of non-cardiac thoracic and abdominal abnormalities, or even an alternative option when parents do not consent to autopsy.

A practical review of adipocere: Key findings, case studies and operational considerations from crime scene to autopsy

After death, the body begins decomposition, a process that starts with the breakdown of organic matter and typically leads to the complete degradation of a body. Such a process is highly affected by (micro and macro) environmental factors of intrinsic and extrinsic nature. Adipocere is a substance formed from the decomposition of adipose tissue and represents a disruption to the typical decomposition process. Such disruption causes decomposition to slow or arrest completely, placing a body into a state of preservation, and determines complications in the estimation of the time since death (Post-Mortem Interval, PMI). While several studies have been performed on the nature, the formation and the degradation of adipocere, there is still no reliable model to assess the PMI of a body exhibiting it. Case studies are an important source to aid pathologists and investigators during a case. This review presents a summary and an update on the knowledge surrounding the chemistry and the factors affecting adipocere formation and degradation, the timing and the distribution of adipocere throughout a body, and the techniques used to investigate it. Furthermore, a table of the most important case studies involving adipocere since 1950, several images and descriptions of recent cases and operational considerations for the best practice at the crime scene and autopsy are presented to be used as a reference to facilitate forensic professionals in adipocere cases.

Pseudolesion in the right parafissural liver parenchyma on CT: The base is found in embryology and collagen content

Background

Computed tomography (CT) images of livers may show a hypo-attenuated structure alongside the falciform ligament, which can be a focal fatty pseudolesion and can mimic a malignancy. The preferred location is on the right parafissural site, ventral in segment IVa/b. The etiology is not clear, nor is it known how the histology of this location develops. These are evaluated in this study.

Methods

40 adult cadavers with autopsy and / or postmortem CT in a university hospital and a forensic center were included. Liver biopsies were taken at the left side of the falciform ligament as control, and at the right side as the possible precursor of a pseudolesion; these were examined for collagen and fat content. Cadavers with steatotic (>5% fat) or fibrotic (>2% collagen) control samples were excluded.

Results

Significantly more collagen was present in the right parafissural liver parenchyma: median 0.68% (IQR: 0.32–1.17%), compared to the left side 0.48% (IQR: 0.21–0.75%) (p 0.008), with equal fat content and CT attenuation values. The etiophysiology goes back to the demise of the umbilical venes in the early embryonic and neonatal period.

Conclusions

The right parafissural area contains more collagen and an equal amount of fat compared to the control left side. This supports the hypothesis of delayed, ‘third’ inflow: the postnatal change in blood supply from umbilical to portal leaves the downstream parafissural area hypoperfused leading to hypoxia which in turn results in collagen accumulation and the persistence of paraumbilical veins of Sappey.

Use of Postmortem Computed Tomography to Detect Bowel Obstruction and its Relationship to the Cause of Death

Bowel distension frequently indicates bowel obstruction, which is a common diagnosis in clinical radiology. Typically, symptoms and complaints lead to radiological examinations and the detection of the etiology. Untreated intestinal obstructions can lead to a fatal outcome through cardiac failure due to septic shock. Certain of these cases undergo medicolegal investigations depending on the case history, the condition of the decedent, the location of the finding, or recent visits to medical professionals. Computed tomography (CT) is a recommended method in clinical radiology for the detection of bowel obstruction, which is indicated by bowel distension and further radiological signs (eg, the whirl sign, which indicates a volvulus). Postmortem CT (PMCT) has increased worldwide, but PMCT differs from clinical CT; thus, the question of whether PMCT is also reliable for the detection of bowel obstruction in decedents or is negatively affected by postmortem modifications should be discussed. This study consists of 10 cases displaying radiological signs of bowel obstruction. Apart from bowel distension, the most common radiological signs (whirl sign, coffee bean sign, bird beak sign, and u-shape sign) are described and depicted. All decedents underwent autopsy and had a postmortem interval of less than 72 hours. Based on these cases, we assess the reliability of PMCT for detecting bowel obstruction and determining its relationship to the cause of death.