Realistic three-dimensional imaging of injuries in forensic medicine - Survey-based method comparison of CRT and VRT

OBJECTIVE

A comparison between Cinematic Rendering Technique (CRT) and Volume Rendering Technique (VRT) in cases with postmortem CT-angiography (PMCTA) was carried out.

METHODS

For different injuries seen in PMCTA, a VRT and a CRT image of exactly the same pathological section was generated. Two questionnaires were created, one with CRT and one with VRT reconstructions, with the same questions per 3D-image. The questionnaires were sent to forensic pathologists, lawyers and police officers. In total eleven different injuries had to be analyzed.

RESULTS

In total 109 questionnaires were answered fully. Of these returnees, 36 stated that they were forensic pathologists. Seventy-three people were assigned to the group of medical laypersons, in the study this group consists mainly of police officers, judges and lawyers. Between the two software programs CRT and VRT that were compared, no significant difference could be identified in any of the participating groups with regard to the assessment of the life-threatening nature of the injury images shown. When asked about the comprehensibility of pathology, there was a significant difference in favour of CRT. This advantage was apparent to named medical laypersons and to forensic pathologists.

CONCLUSIONS

The study showed a positive trend that CRT may be more understandable than VRT. Not only the medical laypersons, but also the forensic physicians found CRT to be beneficial.

Pediatric postmortem CT angiography: validation of vascular access for PMCT angiography in stillbirths, babies and toddlers

PURPOSE

The use of angiography in postmortem CT angiography (PMCTA) has several advantages. In adults, femoral vascular access is well established. Due to the small and specific anatomy in fetuses and infants, the technique has to be adapted, especially regarding the vascular access. The aim of this study was to evaluate vascular access for pediatric PMCTA (pedPMCTA).

MATERIALS AND METHODS

Ten pedPMCTAs were performed in stillbirths, babies, and one toddler. A femoral approach by cannulation of the femoral artery and vein, an umbilical approach by cannulation of the umbilical vessels, and an intraosseous approach by an intraosseous needle were evaluated by handling and resulting imaging.

RESULTS

The insertion of a cannula with a size of 18-20 G in the femoral vessels was possible in babies. An umbilical access with peripheral venous cannulas with a size of 14-20 G was feasible in stillbirths and newborns. An intraosseous access is advisable as equal alternative to umbilical and in cases where a femoral access is not possible. The most significant problem with the vascular access is the extravasation of contrast media, but this can be reduced significantly with practice.

CONCLUSION

When performing pedPMCTA, an umbilical vascular access is recommended if an umbilical cord with open vessels is still present. Otherwise, a bone marrow access should be preferred in the presence of an arteriovenous shunt or if only the venous system needs to be shown. If that is not the case, the femoral access with the possibility to separate venous and arterial scan should be used.