Air as a Contrast Medium for Targeted Post-mortem Computed Tomography Cardiac Angiography

AbstractScopolamine is an alkaloid which acts as competitive antagonists to acetylcholine at central and peripheral muscarinic receptors. We report the case of a 41-year-old male convict with a 27-year history of cannabis abuse who suddenly died in the bed of his cell after having smoked buscopan® tablets. Since both abuse of substances and recent physical assaults had been reported, we opted for a comprehensive approach (post-mortem computed tomography CT (PMCT), full forensic autopsy, and toxicology testing) to determine which was the cause of the death. Virtopsy found significant cerebral edema and lungs edema that were confirmed at the autopsy and at the histopathological examination. Scopolamine was detected in peripheral blood at the toxic concentration of 14 ng/mL in blood and at 263 ng/mL in urine, and scopolamine butyl bromide at 17 ng/mL in blood and 90 ng/mL in urine. Quetiapine, mirtazapine, lorazepam, diazepam, and metabolites and valproate were also detected (at therapeutic concentrations). Inmates, especially when they have a history of drug abuse, are at risk to use any substance they can find for recreational purposes. In prisons, active surveillance on the management and assumption of prescribed drugs could avoid fatal acute intoxication.

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Error estimation on extracorporeal trajectory determination from body scans

International Journal of Legal Medicine ◽

10.1007/s00414-021-02676-y ◽

2021 ◽

Author(s):

F. Riva ◽

U. Buck ◽

K. Buße ◽

R. Hermsen ◽

E. J. A. T. Mattijssen ◽

...

Keyword(s):

Computed Tomography ◽

Soft Tissue ◽

Supine Position ◽

Post Mortem ◽

Surface Scanning ◽

3D Data ◽

Gravitational Pull ◽

Scanned Images ◽

Source Of Error ◽

Trajectory Determination

AbstractThis study explores the magnitude of two sources of error that are introduced when extracorporeal bullet trajectories are based on post-mortem computed tomography (PMCT) and/or surface scanning of a body. The first source of error is caused by an altered gravitational pull on soft tissue, which is introduced when a body is scanned in another position than it had when hit. The second source of error is introduced when scanned images are translated into a virtual representation of the victim’s body. To study the combined magnitude of these errors, virtual shooting trajectories with known vertical angles through five “victims” (live test persons) were simulated. The positions of the simulated wounds on the bodies were marked, with the victims in upright positions. Next, the victims were scanned in supine position, using 3D surface scanning, similar to a body’s position when scanned during a PMCT. Seven experts, used to working with 3D data, were asked to determine the bullet trajectories based on the virtual representations of the bodies. The errors between the known and determined trajectories were analysed and discussed. The results of this study give a feel for the magnitude of the introduced errors and can be used to reconstruct actual shooting incidents using PMCT data.

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A deep-learning method using computed tomography scout images for estimating patient body weight

Scientific Reports ◽

10.1038/s41598-021-95170-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Shota Ichikawa ◽

Misaki Hamada ◽

Hiroyuki Sugimori

Keyword(s):

Computed Tomography ◽

Body Weight ◽

Deep Learning ◽

Contrast Medium ◽

Model Performance ◽

Ct Scanning ◽

Drug Dosing ◽

Body Weights ◽

Dose Management ◽

Medium Dose

AbstractBody weight is an indispensable parameter for determination of contrast medium dose, appropriate drug dosing, or management of radiation dose. However, we cannot always determine the accurate patient body weight at the time of computed tomography (CT) scanning, especially in emergency care. Time-efficient methods to estimate body weight with high accuracy before diagnostic CT scans currently do not exist. In this study, on the basis of 1831 chest and 519 abdominal CT scout images with the corresponding body weights, we developed and evaluated deep-learning models capable of automatically predicting body weight from CT scout images. In the model performance assessment, there were strong correlations between the actual and predicted body weights in both chest (ρ = 0.947, p < 0.001) and abdominal datasets (ρ = 0.869, p < 0.001). The mean absolute errors were 2.75 kg and 4.77 kg for the chest and abdominal datasets, respectively. Our proposed method with deep learning is useful for estimating body weights from CT scout images with clinically acceptable accuracy and potentially could be useful for determining the contrast medium dose and CT dose management in adult patients with unknown body weight.

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A technical note on intra-arterial cone-beam computed tomography for the evaluation of flow-diverter stents: Image quality differences between diluted and non-diluted contrast medium

Interventional Neuroradiology ◽

10.1177/1591019919890929 ◽

2019 ◽

Vol 26 (2) ◽

pp. 164-169

Author(s):

Naci Kocer ◽

Sedat G Kandemirli ◽

Daniel Ruijters ◽

Michalis Mantatzis ◽

Osman Kizilkilic ◽

...

Keyword(s):

Computed Tomography ◽

Image Quality ◽

Contrast Medium ◽

Cone Beam Computed Tomography ◽

Vessel Wall ◽

Flow Diverter ◽

Cone Beam ◽

Gray Scale ◽

Stent Deployment ◽

Contrast Technique

Background Design of flow-diverter stents for flexibility, tractability, and low profile limits their radiopacity on conventional digital subtraction angiography. Cone-beam computed tomography (CBCT) offers higher spatial resolution for the evaluation of flow-diverter stents. However, CBCT requires optimal dilution and timing of contrast medium for simultaneous visualization of the stent, arterial lumen, and vessel wall. There are only limited data on the effects of different contrast dilutions on CBCT image quality in neurointerventional applications. Materials and methods In our institution, intra-arterial CBCTs were acquired during stent deployment and at follow-ups with 10% diluted contrast. We had recently started acquiring intra-arterial CBCTs with non-diluted contrast. Retrospective analysis of our flow-diverter data identified eight cases with different aneurysm locations who had intra-arterial CBCT with 10% diluted contrast immediately after flow-diverter stent deployment and with non-diluted contrast technique during follow-ups. For each case, the image quality between diluted and non-diluted contrast techniques was compared qualitatively by assessing stent visualization and quantitatively by plotting gray-scale intensity values along the vessel lumen. Results In two sets of CBCT images per each case, there was no substantial difference between diluted and non-diluted CBTC techniques for the evaluation of stent architecture and lumen opacification. Gray-scale intensity values perpendicular to the lumen revealed similar intensity values along the neighboring parenchyma, vessel wall, and lumen for the two different contrast techniques. Conclusion Intra-arterial CBCT angiography can be performed without contrast dilution and still achieve adequate image quality in certain cerebral aneurysms treated with flow diverter. The non-diluted contrast technique avoids the time loss during preparation of diluted contrast and installation of diluted contrast to the injector in angiography suites with a single power injector.

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Fibrotic progression and radiologic correlation in matched lung samples from COVID-19 post-mortems

Virchows Archiv ◽

10.1007/s00428-020-02934-1 ◽

2020 ◽

Cited By ~ 3

Author(s):

Emanuela Barisione ◽

Federica Grillo ◽

Lorenzo Ball ◽

Rita Bianchi ◽

Marco Grosso ◽

...

Keyword(s):

Computed Tomography ◽

Diffuse Alveolar Damage ◽

Ground Glass Opacity ◽

Post Mortem ◽

Mechanically Ventilated ◽

Illness Duration ◽

Transbronchial Lung Cryobiopsy ◽

Histopathologic Analysis ◽

Lung Lobes

Abstract Data on the pathology of COVID-19 are scarce; available studies show diffuse alveolar damage; however, there is scarce information on the chronologic evolution of COVID-19 lung lesions. The primary aim of the study is to describe the chronology of lung pathologic changes in COVID-19 by using a post-mortem transbronchial lung cryobiopsy approach. Our secondary aim is to correlate the histologic findings with computed tomography patterns. SARS-CoV-2-positive patients, who died while intubated and mechanically ventilated, were enrolled. The procedure was performed 30 min after death, and all lung lobes sampled. Histopathologic analysis was performed on thirty-nine adequate samples from eight patients: two patients (illness duration < 14 days) showed early/exudative phase diffuse alveolar damage, while the remaining 6 patients (median illness duration—32 days) showed progressive histologic patterns (3 with mid/proliferative phase; 3 with late/fibrotic phase diffuse alveolar damage, one of which with honeycombing). Immunohistochemistry for SARS-CoV-2 nucleocapsid protein was positive predominantly in early-phase lesions. Histologic patterns and tomography categories were correlated: early/exudative phase was associated with ground-glass opacity, mid/proliferative lesions with crazy paving, while late/fibrous phase correlated with the consolidation pattern, more frequently seen in the lower/middle lobes. This study uses an innovative cryobiopsy approach for the post-mortem sampling of lung tissues from COVID-19 patients demonstrating the progression of fibrosis in time and correlation with computed tomography features. These findings may prove to be useful in the correct staging of disease, and this could have implications for treatment and patient follow-up.

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