Post Mortem Computed Tomography: An innovative tool for teaching anatomy within pre-registration nursing curricula

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Background There is significant change throughout the world regarding Post Mortem Computed Tomography (PMCT) as an adjunct or a replacement to the traditional invasive autopsy. Of interest, is the ability to demonstrate visually two and three dimensional normal soft tissue, organ and skeletal anatomy, as well as natural disease and trauma pathology. Objectives The objective was to compare formal traditional methods of teaching anatomy and pathology (pictures and diagrams) to pre-registration student nurses with supplementary PMCT 2/3D generated images, videos and printed anatomical models. The specific objective was to determine if these tools would increase the students’ perception of their understanding and learning experience of the subject area. Design A quasi-experimental within-subject design was chosen. Setting A School of Nursing and Midwifery within a Higher Education Institution in the UK. Participants Purposeful sampling of 57 voluntary informed consented pre-registration student nurses. Method Students were initially exposed to teaching of normal anatomy and common fractures using traditional methods. Data was then collected following the teaching session using a questionnaire entailing both quantitative and qualitative elements. The teaching session was then repeated with the same students but with the inclusion of PMCT of all the same normal anatomy and fractures. Data was then collected again using the same questionnaire. Both questionnaires were then compared. Results The quantitative findings proved highly significantly proved (P = < 0.01) that the inclusion of Post Mortem Computed Tomography when teaching normal anatomy and pathology increases preregistration nursing students’ perception of their understanding and learning experience. The qualitative results revealed three positive themes concerning visual learning, realism and patient empathy. Conclusion Including Post Mortem Computed Tomography imagery enables nurse academics to provide students with a virtual tour of the human body and a rich, authentic learning experience of a real individual who experienced a relevant clinical scenario that nurses are likely to encounter in their careers

Forces generated in stabbing attacks:an evaluation of the utility of the mild, moderate and severe scale

The commonest way of killing in the UK is by asharp instrument. Knight reported in 1975 that it is impossibleto discern with any degree of certainty the degree of force usedto create a stab wound. Despite this, expert witnesses continueto approximate the degree of force used for their reports andevidence in court. It is usually subjectively categorized as mild,moderate or severe, based solely on the examination of thewound. We undertook a study considering forces generated ina range of blunt trauma actions, using a novel force plate dy-namometer to measure the peak forces obtained by adult maleand female volunteers. We then studied forces generated bystabbing skin simulants and porcine samples with knives andscrewdrivers. Men generated more force than women duringstabbings which was found to be equivalent to somewherebetween the blunt trauma actions of pushing a button to asingle-handed push. When asked to stab using what theythought was mild, moderate and severe force, although volun-teers were able to actively decide the force used, the actualforce was found to be influenced by the weapon, sex of theindividual, hand used and biological/anatomical sitepenetrated. This study shows that the forces generated by vol-unteers in mild, moderate and severe stabbing tests in almost allcases were significantly greater than the forces required for skinpenetration. We suggest that the use of subjective force scales isinappropriate. Rather than use of a subjective scale, we suggestthat the force required in any stabbing requires investigation infour areas: the tip radius of the weapon, minimal force requiredfor penetration, the sex of the assailant and whether the forcerequired for penetration is greater than that that can be gener-ated by a person stabbing. This allows for the use of anevidence-based two-tier scale to suggest the force required Forces generated in stabbing attacks: an evaluation of the utility of the mild, moderate and severe scale (PDF Download Available). Available from: https://www.researchgate.net/publication/320429308_Forces_generated_in_stabbing_attacks_an_evaluation_of_the_utility_of_the_mild_moderate_and_severe_scale [accessed Oct 20 2017]

The use of mid-arm circumference for the estimation of adult body weight: A post mortem computed tomography approach

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Purpose: Cadaver body weight (BW) is to be documented, where possible, in all forensic autopsy examinations.However, it may not always be possible to ascertain an accurate BW if, for example, functioning weighing equipment is unavailable or the body is incomplete. This research aimed to translate an adult clinical prehospital method which uses a mid-arm circumference (MAC) measurement to estimate BW to establish a post mortem computed tomography (PMCT) technique for adult cadaver BW estimation. Method: The clinical method was adapted for PMCT bone and soft tissue methods. Right and left MAC measurements were obtained by four independent observers from sixty-six (45 males and 21 females) consented research adult PMCT scans using the Osirix DICOM viewer. All observers rated MAC quality score on each arm from 0 (very poor) to 3 (good). Results: In the final group of fifty-five with MAC quality score ≥ 1, MAC measurements correlated well with actual BW (r=0.87) and yielded excellent intra- and inter-observer reliability. There were no statistical differences between the two MAC methods, sexes or side of arm. Mean estimated BW by previous study Equation, BW=(4×MAC)-50, was 0.47 kg greater than mean actual BW with limits of agreement of 12.7 kg; this would be reduced to 9.2 kg if an outlier were excluded. Conclusions: The study identifies a quick and easy PMCT technique to estimate adult BW using PMCT. However, the result remains only an estimation and caution should be expressed if a result is applied to medico-legal cases

Diagnostic accuracy of post-mortem CT with targeted coronary angiography versus autopsy for coroner-requested post-mortem investigations: a prospective, masked, comparison study.

England and Wales have one of the highest frequencies of autopsy in the world. Implementation of post-mortem CT (PMCT), enhanced with targeted coronary angiography (PMCTA), in adults to avoid invasive autopsy would have cultural, religious, and potential economic benefits. We aimed to assess the diagnostic accuracy of PMCTA as a first-line technique in post-mortem investigations.This article is freely available via Open Access. Click on the Additional Link above to access the full-text via the publisher's site

How taphonomic alteration affects the detection and imaging of striations in stab wounds

Stabbing with a kitchen knife is a common methodof homicide in Europe. Serrated knives may leave tool mark-ings (striations) in tissues. Documentation of striations is nec-essary for their use as forensic evidence. Traditional methods(physical casting and photography) have significant limita-tions, and micro-computed tomography (micro-CT) has beentrialled in cartilage toBvirtually cast^wounds. Previous re-search has shown the proportion of striations in cartilage fallsfollowing decomposition. This project has investigated theeffects of taphonomic alteration and documentation methodsof striations in porcine skin. Fresh, decomposed, mummified,burnt and waterlogged stab wounds in a porcine analoguewere excised and imaged using photography, stereo-opticalmicroscopy and micro-CT. The proportion of striations ineach taphonomic group was determined from the images byindependent analysts. Striations were observed more frequent-ly in serrated blade wounds, although they were also identifiedin non-serrated blade wounds. The proportion of woundsshowing striations declined following decomposition. An in-versely proportional linear correlation between advancing de-composition and proportion of striations existed. Dehydration(mummification and burning) rendered serrated and non-serrated blade wounds indistinguishable. Water compositionaffected the preservation of striations. Identification ofstriations gradually declined after decomposition in tap water,but persisted to a point when left in brackish water. All threetechniques imaged striations; however, the optimum tech-nique was stereo-optical microscopy due to practical advan-tages and specific limitations affecting photography and mi-cro-CT. This study demonstrates the effects of taphonomicalteration on striations and suggests stereo-optical microscopyis the optimum method for their documentation

A systematic autopsy survey of human infant bridging veins

In the first years of life, subdural haemorrhage (SDH) within the cranial cavity can occur through accidental and non-accidental mechanisms as well as from birth-related injury. This type of bleeding is the most common finding in victims of abusive head trauma (AHT). Historically, the most frequent cause of SDHs in infancy is suggested to be traumatic damage to bridging veins traversing from the brain to the dural membrane. However, several alternative hypotheses have been suggested for the cause and origin of subdural bleeding. It has also been suggested by some that bridging veins are too large to rupture through the forces associated with AHT. To date, there have been no systematic anatomical studies on infant bridging veins. During 43 neonatal, infant and young child post-mortem examinations, we have mapped the locations and numbers of bridging veins onto a 3D model of the surface of a representative infant brain. We have also recorded the in situ diameter of 79 bridging veins from two neonatal, one infant and two young children at post-mortem examination. Large numbers of veins, both distant from and directly entering the dural venous sinuses, were discovered travelling between the brain and dural membrane, with the mean number of veins per brain being 54.1 and the largest number recorded as 94. The mean diameter of the bridging veins was 0.93 mm, with measurements ranging from 0.05 to 3.07 mm. These data demonstrate that some veins are extremely small and subjectively, and they appear to be delicate. Characterisation of infant bridging veins will contribute to the current understanding of potential vascular sources of subdural bleeding and could also be used to further develop computational models of infant head injury