Targeting tumor heterogeneity: multiplex-detection-based multiple instance learning for whole slide image classification.

MOTIVATION: Multiple instance learning (MIL) is a powerful technique to classify whole slide images (WSIs) for diagnostic pathology. The key challenge of MIL on WSI classification is to discover the critical instances that trigger the bag label. However, tumor heterogeneity significantly hinders the algorithm's performance. RESULTS: Here, we propose a novel multiplex-detection-based multiple instance learning (MDMIL) which targets tumor heterogeneity by multiplex detection strategy and feature constraints among samples. Specifically, the internal query generated after the probability distribution analysis and the variational query optimized throughout the training process are utilized to detect potential instances in the form of internal and external assistance, respectively. The multiplex detection strategy significantly improves the instance-mining capacity of the deep neural network. Meanwhile, a memory-based contrastive loss is proposed to reach consistency on various phenotypes in the feature space. The novel network and loss function jointly achieve high robustness towards tumor heterogeneity. We conduct experiments on three computational pathology datasets, e.g. CAMELYON16, TCGA-NSCLC, and TCGA-RCC. Benchmarking experiments on the three datasets illustrate that our proposed MDMIL approach achieves superior performance over several existing state-of-the-art methods. AVAILABILITY AND IMPLEMENTATION: MDMIL is available for academic purposes at https://github.com/ZacharyWang-007/MDMIL.

Effectiveness of low dose computed tomography to detect fractures in paediatric suspected physical abuse: a systematic review.

PURPOSE: The skeletal survey X-ray series is the current 'gold standard' when investigating suspected physical abuse (SPA) of children, in addition to a non-contrast computed tomography (CT) brain scan. This systematic literature review synthesised findings of published research to determine if low dose computed tomography (LDCT) could detect subtle fractures and therefore replace the skeletal survey X-ray series in the investigation of SPA in children aged under 3 years. METHODS: Five electronic databases and grey literature were systematically searched from their inception to 28 April 2022. Primary studies were included where the population comprised paediatric patients up to 16 years and LDCT was used to detect fractures associated with SPA. Studies involving imaging investigations of the head, standard dose CT examinations or accidental trauma were excluded. RESULTS: Three studies met the inclusion criteria, all of which were case series. These studies did not report many of the criteria required to compare the accuracy of LDCT to X-ray, i.e. they did not meet the criteria for a diagnostic accuracy test. Therefore, it is difficult to conclude from the case series if LDCT is accurate enough to replace X-rays. CONCLUSION: Due to the gap in current literature, a phantom study and subsequent post-mortem CT study are recommended as the primary investigative methods to assess the ability of low-dose CT to identify the subtle fractures associated with SPA and to calculate how low the achievable CT dose can be.

Estimating dental age of New Zealand juveniles and subadults using Demirjian's method.

Reference data for dental age estimate is sparse in New Zealand (NZ), with only two contemporary studies. Te Moananui et al. (J For Sci. 53(2), 2008) presented modified Demirjian percentile curves to estimate dental age of Pasifika, Maori, and European males and females (n = 1383), while Timmins et al. (Forensic Sci Med Pathol. 8:101-8, 2012) found the Demirjian method (1973) was valid for a smaller sample (n = 200) of unknown ancestry. The study presented here sought to validate the Demirjian and the Te Moananui methods for a sample of the NZ population of unknown ancestry and a subgroup of known ancestry i.e., Pasifika, Maori and European, for males and females. The Demirjian method (1976) was applied to the current study's sample consisting of 3523 individuals aged 4 to < 20 years. The seven left mandibular teeth (third molar excluded) and tooth scores were summed for each individual, with the Te Moananui methods applied to this subgroup. The results revealed these methods to be less than ideal for estimating dental age of the NZ sample, for both males and females. The probit regression form of Transition Analysis (TA) was employed to calculate the mean age entering each tooth stage, for the seven teeth, to reduce age mimicry that is commonly associated with traditional regression analysis. TA results revealed Pasifika and Maori individuals to be more advanced than Caucasian individuals. The sex groups were also compared to the mean ages presented by Demirjian and Levesque with mixed results (J Dent Res. 59(7):1110-22, 1980), highlighting the need for more research in this area.

Typical median effective radiation doses using an anthropomorphic bone fracture phantom for initial radiographic skeletal surveys in the investigation of suspected physical abuse.

BACKGROUND: A series of 31 radiographs is recommended by the Royal College of Radiologists (RCR) when investigating suspected physical abuse (SPA). OBJECTIVE: To determine the radiation dose delivered for skeletal surveys performed for SPA in Victorian radiology departments based on their local protocols. MATERIALS AND METHODS: A 5-year-old paediatric bone fracture phantom was radiographed at five radiology sites using both the RCR recommended protocol and, where applicable, the local departmental SPA protocol. The radiation doses were measured and recorded. These were scaled down to estimate the effective radiation doses for a 2-year-old child at each site and the associated radiation risks estimated. RESULTS: The median effective dose for all radiographic projections in the RCR skeletal survey radiographic series was 0.09 mSv. The estimated risk of radiation-induced cancer and radiation-induced death from cancer for 2-year-old children is classified as "very low," with girls having a higher risk than boys. CONCLUSION: The median effective radiation dose for the RCR skeletal survey for imaging in SPA was 0.09 mSv resulting in a "very low" additional risk of radiation-induced cancer. The authors will now aim to ascertain whether whole-body CT skeletal survey can replace the radiographic series for imaging in SPA while maintaining a comparable radiation dose.

Technology-facilitated sexual assault in children and adolescents; is there a cause for concern? Fourteen years of experience at a metropolitan forensic paediatric medical service.

AIM: To quantify and characterise sexual assaults occurring after 12-17-year-old children connect with an alleged offender online (technology-facilitated sexual assault: TFSA) examined at a paediatric forensic medical service in Melbourne, Australia between 2014 and 2020. To compare these findings to a previous 7-year audit (2007-2013) to determine if there has been an increase in TFSA over the last 14 years. METHODS: A retrospective audit was undertaken of medical records of children aged 12-17 who underwent forensic medical examinations at the Victorian Forensic Paediatric Medical Service following an allegation of sexual assault, between 1 January 2014 and 31 December 2020. Cases identified as being technology facilitated were further analysed. Results from 2014 to 2020 7-year cohort were then compared to an existing audit over the preceding 7-year period (2007-2013). RESULTS: Of 515 sexual assault cases between 2014 and 2020, 70 (14%) victims reported connecting with the offender on a technological platform, compared to 4% of cases between 2007 and 2013. In 2019 and 2020, TFSA comprised almost one-fifth of caseload. Of the 70 TFSA cases, the majority occurred at the first face-to-face meeting following a variable period of online communication. Approximately one-third of TFSA's occurred at the offender's residence, and another third in a public place (park, public toilets). Technological platforms used evolved over the 14-year study period. CONCLUSIONS: The proportion of TFSA caseload seen at an Australian paediatric forensic medical service increased over the last 14 years, with common characteristics to these sexual assaults suggested.

Orofacial injuries in child family homicide: a population study.

Child family violence homicide (FVH) is a significant public health problem in Australia and globally. Population-wide studies of orofacial injuries in child FVH are uncommon despite their recognized importance. This whole population descriptive study of orofacial injuries in child FVH in Victoria, Australia aims to implement a novel methodological approach to provide an overview of child FVH and describe frequency and patterns of abusive orofacial injuries. Closed cases of child FVH aged 0-17 years, January 2000-December 2018, were identified from screening all Victorian assault deaths for eligible offender relationships. Significant associations of clinical/demographic characteristics were explored using two-step clustering and the Spearman correlation coefficient. Of 895 closed homicide cases, 358 were FV-related. Of the 53 child FVH, 40 were eligible for injury analysis with 36 of these cases (90%) having orofacial injuries. Among these 36 cases, 72% were aged 0-4 years, males predominated (64%) and the injury mechanism was blunt force for 56%. The discrete orofacial injury frequency was associated with the non-orofacial injury frequency (rho: 0.362, 2-tailed p < 0.03). A three-cluster statistical solution was identified, each represented by an injury mechanism. The largest cluster identified a pattern of blunt force trauma in 0-4 years with drug presence, high average non-orofacial injury numbers and parent-offenders. A novel methodological approach was implemented to comprehensively describe the frequency, nature, patterns and risk indicators of orofacial injuries in child FVH. It explored associations between a wide range of clinical and demographic characteristics, which might have otherwise been missed in summary description. These methods will potentially underpin future comparative studies of intentional-unintentional child injuries and fatal-nonfatal child abuse. The study narrows a significant research gap regarding patterns of inflicted injuries, and demographic and clinical indicators in child FVH potentially informing future systematic classification processes, risk assessment tools and pathways to FV intervention.

Methods in population study of orofacial injuries in Victorian family violence homicides.

This study standardized the methods used in the determination of orofacial injuries in Victorian family violence homicides and informed potential control selection for an analytic study. Dental service contacts with family violence victims may be intervention avenues due to the presence of abusive injuries in the orofacial region. All Victorian family homicides from January 2000-September 2018 were identified by determining the kinship/relationship and grouped by age. A 20% random sample of adult cases, aged 18-64 years was selected. The median number of orofacial injuries in categories of injury mechanisms/age/gender and the nature of abusive orofacial injuries was reported for the sample. Of 357 closed cases of family homicide, 261 were adults aged 18-64 years. Offender information and injury mechanism data was available for all closed cases, enabling case selection. Of a random sample of 50 adults, 8 cases were excluded. After 2006, CT scans and photos were present in 20 (91%) and 19 (86.4%) of 22 cases, respectively. The nature and median number of orofacial injuries showed correlation to the reported injury mechanism. Strengths and limitations of the used methods were assessed. Not all cases were compatible for assessment of orofacial injuries, thus serving as an additional criterion for exclusion in our methodology. Further detailed study of the whole population of adults should be limited to the period 2006-2018 where the data is more complete. The mechanism of injury may influence control selection for analytic studies. We present preliminary evidence of the frequent occurrence of orofacial injuries in family violence homicides.

Mandatory reporting of child physical abuse and dental neglect by Australian dentists.

Child protection measures are organized into three major themes: laws; service programs; and status of outcomes of these interventions. Contextually, mandatory reporting of child abuse and neglect is governed by a complex system of State legislation across Australia. The purpose of this review was to investigate the evidence base for the legislative obligations of Australian dentists as mandatory reporters; the functionality of dental practice in the determination of orofacial signs of abuse and neglect; and, relevant knowledge and practice demonstrated by the Australian dental work force. Our research question explores the role of Australian dentists in intervention of child physical abuse and dental neglect. Information was sourced from literature and web-based reviews. Peer reviewed articles included reviews and empirical studies. Official websites/databases were accessed for relevant legislation. The study found that child protection laws lack an evidence base for including/excluding dentists as reporters. Child abuse and neglect is associated with strong orofacial signs, thus imparting a key advantage to utilizing dentists as potential notifiers. An action response to child abuse is not seen in the Australian dental service. This review identifies gaps in the dental literature concerning mandatory reporting, calls for optimization of the related evidence base, and uniform Australian child abuse reporting requirements.

Suicidal ligature strangulation: a systematic review of the published literature.

To summarize the published forensic pathology evidence base in deaths concluded to be the result of suicidal ligature strangulation, an uncommon entity. Four electronic bibliographic databases Medline Ovid, Embase, Scopus, HEINonline were screened for relevant literature. No date restrictions were applied. All English language case reports or case series were included. Articles were evaluated and key data extracted according to predefined criteria. A total of 1554 references eventually yielded 24 papers with 31 eligible case reports. The location of the deaths and background circumstances and history mirror broadly those of suicide generally. The range of ligature types was diverse. 19/31 cases reported one or more knots present. In the remaining 12 cases, the ligatures did not lend themselves to knots. In only one case were laryngeal fractures reported, but the available material does not justify confidence in that report given the significance of the finding. This systematic review has identified and synthesized the evidence from 31 case reports of suicidal ligature strangulation. A forensic pathologist faced with a possible case can locate it within the spectrum of reported cases and therefore identify its common and distinguishing features. Inherent difficulties for research in forensic pathology mean that case reports are an important source of learning and evidence for the discipline. Opportunities for improvement exist especially in harmonizing terminology and standardizing techniques generally, and in reports of suicidal ligature strangulation in particular.

Teaching of forensic odontology in basic dental programmes in nine Australian dental schools: A survey.

PURPOSE: The aim of this survey was to determine whether forensic odontology forms part of the basic dental programme in the nine Australian dental schools, which aspects of forensic odontology were taught, and the barriers and issues that prevent forensic odontology being part of any dental curriculum. The survey also examines the teaching of cranio-facial anatomy and dental record-keeping, as these two subjects can play an important role in forensic odontology. MATERIALS AND METHODS: Study design and participants: A postal questionnaire survey on the teaching of forensic odontology was conducted between November 2016 and April 2017, being sent to the dean of school, head of school, or acting head of school, each representing the nine Australian dental schools. The paper questionnaire consisted of eight questions requesting information concerning whether or not the dental school has faculty staff who are registered forensic odontologists or registered general dentists with a forensic odontology postgraduate qualification, and how many hours of teaching (including lectures and practicals) were dedicated to cranio-facial anatomy and dental record-keeping. RESULTS: Five out of nine dental schools replied to the questionnaire. This gives a response rate of 55.56%. Staff members: Four dental schools had at least one or more forensically trained staff members. Only one dental school did not have a staff member who is trained in forensic odontology. Cranio-facial anatomy: Three out of the five dental schools responded that each of the cranio-facial anatomy lecture and practical programmes were more than 16 hours each throughout the whole dental programme, whereas the other two dental schools responded that each of the lecture and practical programmes were between 7 and 11 hours. Dental record-keeping: All five dental schools responded that the lecture hours dedicated to dental record-keeping are between 1 and 6 hours throughout the whole dental programme. For the practical sessions, three out of the five dental schools responded that the hours dedicated are between 1 and 6 hours. Teaching of forensic odontology: Three out of the five dental schools responded that forensic odontology is taught as part of a dental subject in the dental programme, with the total hours dedicated to the teaching being between 1 and 6 hours, with teaching being delivered in the form of lectures only. Two of the five dental schools that did not teach forensic odontology as part of any dental subjects mentioned that the main reason for not teaching forensic odontology is due to lack of teaching time. CONCLUSION: This is the first Australian project investigating the teaching of forensic odontology in Australian dental schools. The authors found that three dental schools teach forensic odontology; however, it is limited to only 1 to 6 hours of teaching time. All five dental schools teach extensively into cranio-facial anatomy and dental record-keeping. However, as one of the recognised dental specialities in Australia, and the role it plays in justice, human rights and humanitarianism, all Australian dental schools should provide an opportunity for students to learn and be aware of forensic odontology as part of their training programmes, which include the importance of accurate dental records and its application to forensic odontology.

Mortuary operations following mass fatality natural disasters: a review.

This is a critical review to discuss the best practice approaches to mortuary operations in preparation for and the response to natural, mass fatality, disaster events, as identified by a review of published articles. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) Statement guided the identification of potential articles to use in this critical review. Subsequent searches were also conducted to identify articles relating to heat wave, and flood mortality. All identified peer-reviewed studies published in English which discussed the preparation and response of mortuaries to mass fatality natural disasters occurring in developed countries were included. Using the PRISMA-P method of identifying articles, 18 articles were selected for inclusion in this review. Although there are numerous articles which describe the mortuary response to mass fatality incidents, few articles analyzed the response, or discussed the roles which supported and enabled the organization to undertake the task of identifying disaster victims. It is thus difficult to determine objectively if the actions and activities outlined in the articles represent best-practice.

The Foundations of the Comparison Forensic Sciences: Report of the President's Council of Advisors on Science and Technology.

In September 2016, the President's Council of Advisors on Science and Technology (PCAST) in the United States published its report to the President entitled Forensic Science in Criminal Courts: Ensuring Scientific Validity of Feature-Comparison Methods. The need for this report arose out of the highly critical 2009 National Research Council report on the state of forensic sciences in the United States. The report had noted that there were particular problems in feature-comparison disciplines where the science underpinning the validity of the discipline was poor. The PCAST report has developed the National Research Council's thinking further. It looked at the foundational validity of a number of forensic disciplines, including, for example, bite mark interpretation in forensic odontology. PCAST concluded that bite mark analysis does not meet the scientific standards for foundational validity. In addition, it felt that the prospects of developing bite mark analysis into a scientifically valid method were poor, and they advised against government investment in research to try to establish such validity. The principles discussed in this report, focused as they are on forensic science, will need to be digested by forensic medicine. Forensic medicine will be increasingly called upon to justify the validity of the various areas in which its practitioners provide expert evidence.

The use of computed tomography in determining development, anomalies, and trauma of the hyoid bone.

PURPOSE: Recognition of injury to the hyoid bone is intrinsic to post-mortem examination. Given its superficial location in the neck hyoid fractures are generally associated with some form of compressive neck force although they are well recognized in the peri-mortem period, in the context of manual handling and resuscitation. Hyoid fractures are variably reported to occur in manual strangulation and during hanging. METHODS: In this study Computer Tomography (CT) scans of the head and neck of 431 deceased persons (235 males and 196 females) between the ages of 1 day and 100 years of age (mean age 35.93 ± 24.15) and including 25 victims of hangings were examined to reveal the pattern of age-related change and the types of injury that occurred. Hyoid variants were also documented. RESULTS: The synchondroses between greater cornua and body were found to progressively fuse with age although in the current sample 20% non-fusion was observed beyond 65 years of age. Sex differences were evident in adult hyoid bones and discriminant function analysis correctly confirmed sex in 74.7% of cases. CONCLUSIONS: The greatest age-related changes occurred from puberty to post-adolescence and a linear regression equation successfully assessed age into three general categories in 87.7% of cases. Hyoid fractures were documented in 24% of victims of hangings and while previous reports indicate these are more likely in older age, when synchondroses are fused, in this study the average age of victims with fracture was 27 ± 10 years. In the majority of cases the site of ligature was below the hyoid bone and in only one on the hyoid body.

Post-mortem CT findings in a case of necrotizing cellulitis of the floor of the mouth (Ludwig angina).

Ludwig angina is a rare but potentially lethal infection of the submandibular space that can cause significant upper airway obstruction. We report a case of undiagnosed Ludwig angina that progressed rapidly to death. Ludwig angina was suspected after post-mortem computed tomography (PMCT) found swollen mylohyoid muscle with stranding in subcutaneous fat, thickening of deep fascia, and local lymphadenopathy. Subsequently, an autopsy revealed woody induration of the submental region and liquefactive necrosis of the mylohyoid muscle, confirming the diagnosis. It is likely that the dental abscess identified on PMCT was the source of infection. Multiple invasive medical procedures were performed on the subject by the ambulance crew prior to his death. PMCT assisted further in determining procedural success.

Bite marks: To opine or not to opine?

Much has been written about bite mark comparisons and bite mark analysis. It has largely been written for, and remained within the domain of, the forensic odontologist despite the limited number of such specialists and the even smaller subset who have expertise in this area. For those health professionals who work in the field of clinical forensic medicine, most will not have access to a forensic odontologist. Courts can be reticent about the costs involved in obtaining another expert opinion. For health professionals, who will likely encounter more bite marks in their career than forensic odontologists, the difficulty is knowing what can legitimately be opined about such injuries.

Facial recognition for disaster victim identification.

Mass disaster events can result in high levels of casualties that need to be identified. Whilst disaster victim identification (DVI) relies on primary identifiers of DNA, fingerprints, and dental, these require ante-mortem data that may not exist or be easily obtainable. Facial recognition technology may be able to assist. Automated facial recognition has advanced considerably and access to ante-mortem facial images are readily available. Facial recognition could therefore be used to expedite the DVI process by narrowing down leads before primary identifiers are made available. This research explores the feasibility of using automated facial recognition technology to support DVI. We evaluated the performance of a commercial-off-the-self facial recognition algorithm on post-mortem images (representing images taken after a mass disaster) against ante-mortem images (representing a database that may exist within agencies who hold face databases for identity documents (such as passports or driver's licenses). We explored facial recognition performance for different operational scenarios, with different levels of face image quality, and by cause of death. Our research is the largest facial recognition evaluation of post-mortem and ante-mortem images to date. We demonstrated that facial recognition technology would be valuable for DVI and that the performance varies by image quality and cause of death. We provide recommendations for future research.

Impacts on paediatricians testifying in cases of child maltreatment: protocol for a systematic review.

INTRODUCTION: Paediatricians perform medical assessments for children in cases of suspected child maltreatment. Due to their role with statutory child protection agencies and police, paediatricians may be asked to testify in court about child protection and criminal justice matters. To the authors' knowledge, there has been no previous systematic review of the literature synthesising the evidence on the impacts on paediatricians testifying in cases of child maltreatment. METHODS AND ANALYSIS: A search strategy comprising indexed and key terms will be applied to six electronic reference databases from inception to May 2023: Medline, EMBASE, PsycINFO, CINAHL, Criminal Justice Abstracts and Cochrane Library. Two reviewers will independently screen titles and abstracts and full-text articles against predefined eligibility criteria to identify studies of interest. Conflicts will be independently adjudicated by a third reviewer. ETHICS AND DISSEMINATION: Since the systematic review methodology aims at synthesising information from available publications, this study does not require ethical approval. An article reporting the results of the systematic review will be submitted for publication in a scientific journal, presented at relevant conferences and used in subsequent stakeholder consultations.

Comparison of typical radiation doses and risks using an anthropomorphic 'bone fracture' phantom for commonly performed X-ray projections in a 5-year-old.

INTRODUCTION: Diagnostic reference levels (DRLs) are typical dose levels for medical imaging examinations for groups of standard-sized patients or standard phantoms for broadly defined types of equipment used as a tool to aid optimisation of protection for medical exposures. Currently, there are no paediatric DRLs for conventional radiography (i.e. general X-rays) published in Australia. The aim of this study was to establish typical radiation doses and risks that are representative of those delivered for commonly performed X-ray projections for a 5-year-old/20 kg child using a 5-year-old anthropomorphic 'bone fracture' phantom in three dedicated paediatric radiology departments in Victoria. METHODS: A total of 20 projection images were acquired for a standard 5-year-old/20 kg phantom using digital radiography X-ray equipment. The air kerma-area product (KAP) measured at each centre by a KAP metre, which was calibrated to a national primary standard, was considered to represent the median value for that centre for each X-ray projection. Organ doses and effective dose were estimated using PCXMC software, and risks of radiation-induced cancer and radiation-induced death were calculated based on the BEIR VII report. RESULTS: The typical doses for the individual X-ray projections ranged from 3 mGy•cm2 to 86 mGy•cm2 , whilst the effective doses ranged from 0.00004 to 0.07 mSv. The radiation risks were 'minimal' to 'negligible'. CONCLUSION: The estimation of typical radiation doses and associated risks for a 5-year-old/20 kg phantom study provides reference values for guidance and is a first step in assisting optimisation at other institutions until national DRLs, based on patient data from the clinical setting, are published.

Advancing research on femicide prevention: A mixed methods approach.

Femicide, the killing of women, girls, and infants, is a pervasive problem affecting all global societies. Policy and research are impeded by inaccurate and missing prevalence data, gaps in understanding of femicide, especially for hard-to-reach marginalized populations, and conflicting perceptions between jurisdictions. Leveraging on a combined socio-ecologic model and Public Health approach, the paper spans the methods of a computed tomography-based injury study, an in-depth media-analysis, a legislation evaluation study, and a data barriers' study. Injury patterns, media depiction, and end-user consultations will close the loop on residual problems such as implementation, data gaps, and cultural perceptions. By mixed methods research representing multiple regions, and stakeholders, this project will enhance knowledge on interpersonal, institutional, and societal factors of femicide, advancing the humanitarian forensic discipline. The research method will identify emerging trends and facilitate improvements in tertiary prevention of femicide, specific to resource settings.

Pericardial Effusion Detection on Post-Mortem Computed Tomography Images Using Convolutional Neural Networks.

Pericardial effusion can be a sign of significant underlying diease and, in some cases, may lead to death. Post-mortem computed tomography (PMCT) is a well-established tool to assist death investigation processes in the forensic setting. In practice, the scarcity of well-trained radiologists is a challenge in processing raw whole-body PMCT images for pericardial effusion detection. In this work, we propose a Pericardial Effusion Automatic Detection (PEAD) framework to automatically process raw whole-body PMCT images to filter out the irrelevant images with heart organ absent and focus on pericardial effusion detection. In PEAD, the standard convolutional neural network architectures of VGG and ResNet are carefully modified to fit the specific characteristics of PMCT images. The experimental results prove the effectiveness of the proposed framework and modified models. The modified VGG and ResNet models achieved superior detection accuracy than the standard architecture with reduced processing speed.