Disaster victim identification: new applications for postmortem computed tomography

Abstract:  Mass fatalities can present the forensic anthropologist and forensic pathologist with a different set of challenges to those presented by a single fatality. To date radiography has played an important role in the disaster victim identification (DVI) process. The aim of this paper is to highlight the benefits of applying computed tomography (CT) technology to the DVI process. The paper begins by reviewing the extent to which sophisticated imaging techniques, specifically CT, have been increasingly used to assist in the analysis of deceased individuals. A small scale case study is then presented which describes aspects of the DVI process following a recent Australian aviation disaster involving two individuals. Having grided the scene of the disaster, a total of 41 bags of heavily disrupted human remains were collected. A postmortem examination was subsequently undertaken. Analysis of the CT images of all body parts ( n  = 162) made it possible not only to identify and side differentially preserved skeletal elements which were anatomically unrecognizable in the heavily disrupted body masses, but also to observe and record useful identifying features such as surgical implants. In this case the role of the forensic anthropologist and CT technology were paramount in facilitating a quick identification, and subsequently, an effective and timely reconciliation, of body parts. Although this case study is small scale, it illustrates the enormous potential for CT imaging to complement the existing DVI process.     

Major incident response: collecting ante-mortem data

The Asian tsunami of 26 December 2004, which devastated coastal parts of more than 10 countries in and around the Indian Ocean caused over 200,000 casualties. People from more than 58 nationalities were amongst the victims and subsequently an international effort for disaster victim identification (DVI) was set up, coordinated by Interpol. DVI teams from more than 20 countries took part in the identification process which, because of the complexity of the situation, had to be conducted in an internationally agreed upon procedure. Standard operating protocols of post-mortem (PM) procedures were established for fingerprinting, forensic pathology, forensic odontology and DNA profiling and were crucial in the quality of the entire DVI process of the quickly decomposing bodies. A very important and underestimated part of the DVI process is the gathering of the ante-mortem (AM) data of the persons reported missing in their home countries. In the wake of this tsunami event it appeared to be even more problematic as entire families had died and information was difficult to obtain. As dentistry proved to be the most valuable identification mean--up to 85% of the cases--the AM dental records proved to be crucial elements for DVI. Standard operating protocols (SOP) were again established as to who, where, when and what information had to be collected by the dentists by the AM teams abroad. Transcribing the AM dental information by experienced forensic odontologists was another crucial element in the whole identification procedure as the information had to be loaded into the DVI System International (Plass Data, Holbaek, Denmark) for comparison with incoming PM data. The Interpol DVI Standing Committee thus recommends that forward planning, adequate funding, international cooperation and standardisation are essential to guarantee an effective response to any major mass disaster of this kind in the future.     

Dealing with allelic dropout when reporting the evidential value in DNA relatedness analysis

A method is suggested that allows the use of loci that have shown allelic dropout in kinship analysis as used for disaster victim identification (DVI) and missing person work (MP). This approach uses an extension of a previously published approach to modelling allelic dropout. This method may salvage some information in cases where allelic dropout is hindering DVI or MP work particularly in reconciliations involving a large number of bodies and pedigrees. It should not replace the pursuit of more complete DNA profiles by the normal rework process for such samples.     

Dealing with allelic dropout when reporting the evidential value in DNA relatedness analysis

A method is suggested that allows the use of loci that have shown allelic dropout in kinship analysis as used for disaster victim identification (DVI) and missing person work (MP). This approach uses an extension of a previously published approach to modelling allelic dropout. This method may salvage some information in cases where allelic dropout is hindering DVI or MP work particularly in reconciliations involving a large number of bodies and pedigrees. It should not replace the pursuit of more complete DNA profiles by the normal rework process for such samples.     

The contribution of DNA to the disaster victim identification (DVI) effort

As part of the disaster victim identification (DVI) response to the 2009 Victorian bushfires disaster, a number of scientific disciplines contributed to the human identification process--forensic pathology, anthropology and odontology, as well as fingerprinting and DNA profiling. The DNA laboratory received 182 post-mortem (PM) samples from 120 DVI cases and 236 reference samples corresponding to 163 missing persons (and two non-DVI cases). DNA analysis yielded full DNA profiles for 102 DVI cases and 190 ante-mortem (AM) samples (relating to all 163 missing persons), respectively. Subsequent comparison of DNA profiles, through direct and kinship matching, resulted in the submission of 76 DNA reports to the DVI Reconciliation Centre which assisted in the identification of 67 deceased. This paper describes the contribution of DNA analysis towards the DVI response to the 2009 Victorian bushfires disaster.     

Investigation of Different Ways in Which the CODIS 7.0 May be Used in Mass Disaster Identification

DNA analysis is a key method for the identification of human remains in mass disasters. Reference samples from relatives may be used to identify missing persons by kinship analysis. Different methods of applying the CODIS in disaster victim identification (DVI) were investigated. Two searches were evaluated: (i) relating family relatives to a pedigree tree (FPT) and (ii) relating unidentified human remains to a pedigree tree (UPT). A joint pedigree likelihood ratio (JPLR) and rank were calculated for each search. Both searches were similar in average JPLR and rank. In exceptional cases, namely the existence of a mutation different from the CODIS model, a nonbiological father, a mistake in STR, or incorrect profile association, the UPT search returned one true rank, whereas the FPT search returned no results. This paper suggests a novel strategy to overcome these limitations and increase efficiency in conducting identification of mass disaster victims.     

The Interplay Between Diabetes and Pancreatitis: Two Case Reports of Sudden,Natural Deaths and a Review of the Literature

Diabetes mellitus (DM) is a common disease involving insulin resistance or deficit that, when left unchecked, may cause severe hyperglycemia and subsequent end‐organ damage. Acute pancreatitis (AP) is inflammation of the pancreas that can lead to significant morbidity and mortality. AP and DM both account for a significant amount of sudden deaths, and rarely both disease processes may be present in the same decedent, causing some difficulty in wording the cause of death statement. Although much research has been directed at studying the causes and risk factors for AP and DM, there is a complex interplay between these diseases that is not fully understood. This study presents two autopsy cases of sudden, natural deaths that illustrate this interplay, along with a review of the literature. An algorithm for differentiating AP and DM is then discussed in the context of the presented cases as a proposed aid for forensic pathologists in the certification of such deaths.     

Contemporary methods of labeling dental prostheses--a review of the literature

Forensic identification (ID) based on an assessment of the dentition is commonplace. However, despite an increase in the oral health of Western populations, there are still many millions of individuals who are edentulous and whom have been treated with completed dentures. In the United Kingdom alone over 300,000 patients are rendered edentulous each year. In order to facilitate the ID of such individuals a number of forensic and governmental organizations have recommended that dentures be labeled. A number of labeling systems exist which can be broadly separated into inclusion systems, marking systems, and novel methods. Each of the commonly described systems are demonstrated with an assessment of their strengths and weaknesses. It is recommended that an inclusion denture marker, preferably metallic, should be used in order to withstand the most common postmortem assaults.     

Examples of kinship analysis where Profiler Plus™ was not discriminatory enough for the identification of victims using DNA identification

The identification of the victims of the 2009 Victorian bushfires disaster, as in other mass disasters, relied on a number of scientific disciplines - including DNA analysis. As part of the DVI response, DNA analysis was performed to assist in the identification of victims through kinship (familial matching to relatives) or direct (self source of sample) matching of DNA profiles. The majority of the DNA identifications made (82%) were achieved through kinship matching of familial reference samples to post mortem (PM) samples obtained from the victims. Although each location affected by the bushfires could be treated as a mini-disaster (having a small closed-set of victims), with many such sites spread over vast areas, DNA analysis requires that the short tandem repeat (STR) system used be able to afford enough discrimination between all the DVI cases to assign a match. This publication highlights that although a 9-loci multiplex was sufficient for a DVI of this nature, there were instances that brought to light the short comings of using a 9-loci multiplex for kinship matching--particularly where multiple family members are victims. Moreso it serves to reinforce the recommendation that a minimum of 12 autosomal STR markers (plus Amelogenin) be used for DNA identification of victims which relies heavily on kinship matching.     

Quick Response Code In Acrylic Denture: Will it Respond When Needed?

Use of acids and other caustic substances in destroying the human body to avoid personal identification is drawing great deal of attention in recent times. With rapid industrial growth, incidence of industrial disasters has increased. In an event of chemical industry disaster, human identification can become a challenge. Embedding bar codes and other electronic means for identification in denture have proved to be a novel innovation in identification of edentulous patients. However, the validity of this method in events of chemical extremes has not been assessed. Hence, the study was undertaken to know the effect of different acids on dentures embedded with quick response codes. Results of this study indicate that simple bar code can be readable up to 33 h after acid treatment. With minimal armamentarium, bar code can be generated incorporating large data into it, providing it to be a cheap and reliable means of denture identification.     

Usefulness of Forensic Dental Symbols© and Dental Encoder© database in forensic odontology

Abstract: A new universal graphic dental system, Forensic Dental Symbols^©, has been created to provide precision in the construction of dental records, improve standardization, and increase efficiency in dental identification procedures. Two hundred and thirty‐four different graphic symbols representing the most frequent clinical status for each tooth were designed. Symbols can be then converted to a typographic font and then are ready to use in any computer. For the appropriate use, manipulation, and storage of dental information generated by the Forensic Dental Symbols^©, Dental Encoder^© database has been created. The database contains all the information required by INTERPOL Disaster Victim Identification (DVI)‐dental‐forms. To explore the possibilities that Dental Encoder^© offers, an antemortem dental database from a Spanish population of 3920 military personnel had been constructed. Data generated by Dental Encoder^© were classified into sex and age groups. The program can perform an automatic search of the database for cases that match a selected clinical status presented in a single tooth or a combination of situations for several teeth. Moreover, Dental Encoder^© allows information to be printed on INTERPOL DVI‐dental‐forms, or the inclusion of any completed form into any document, technical report, or identification of dental report.     

Dental hygiene students' matching accuracy when comparing antemortem dental radiographs and oral photographs to simulated postmortem WinID3® odontograms

Matching dental antemortem (AM) and postmortem (PM) data for human identification is especially challenging when the workforce is limited. Dental hygienists have served mass fatality incidents (MFIs) due to dental-related expertise. However, forensics within dental hygiene education and research on transferable skills is limited. This qualitative balance design study assessed senior dental hygiene students' match accuracy of simulated cases varying in dental identifiers based on AM full mouth series (FMS) radiographs and oral photographs to PM WinID3^® odontograms to demonstrate possible disaster victim identification (DVI) transferable skills gained during formal education. A convenience sample of senior dental hygiene students (n = 31) was presented information on WinID3^® interpretation, then presented with 5 mismatched cases and asked to visually interpret each to make 10 total matches; five based on AM FMS with simulated PM WinID3^® odontograms and five based on AM photographs with PM WinID3^® odontograms. Match accuracy scores ranged from 41.9% to 58.1% for cases with 1–10 identifiers, and 77.4% to 93.5% for cases with 11–40 identifiers. Accuracy when matching AM radiographs to PM odontograms versus AM photographs to PM odontograms was compared and revealed no statistical differences in match accuracy depending on image type (p = 0.388 to 1.000). Results of this pilot study suggests transferable match accuracy skills resulted from the participants' dental hygiene formal education. These baseline skills with additional specialized training support the rationale for dental hygienists serving on DVI teams. More research is needed in education and practice when preparing dental hygienists for forensic-based service.     

The Role of Forensic Anthropology in the Examination of the Daegu Subway Disaster (2003, Korea)*

Abstract: Meticulous recovery of victims in the Daegu subway disaster was possible, because charred and fragmented victims were left in situ. Because bodies were piled one over another within the train, appropriate methodology during the recovery was critical to identifying the victims. The disaster area was thoroughly documented with notes, photographs, and schematic drawings of the various locations. The recovery team, comprising two medical examiners and one forensic anthropologist, decided when charred body parts and cremated bones were linked to the same individual based on the anatomy and forensic anthropological examination. Without these recovery procedures, it would not have been possible to efficiently harvest representative DNA sample from most of the victims’ body parts. After the entire process of identification, 136 victims were positively identified, and six victims remained unidentified. This study supports the crucial role of forensic anthropologists in the recovery of victims, especially in fire scenes.     

Use of multislice computed tomography in disaster victim identification--advantages and limitations

After a mass fatality incident (MFI), all victims have to be rapidly and accurately identified for juridical reasons as well as for the relatives' sake. Since MFIs are often international in scope, Interpol has proposed standard disaster victim identification (DVI) procedures, which have been widely adopted by authorities and forensic experts. This study investigates how postmortem multislice computed tomography (MSCT) can contribute to the DVI process as proposed by Interpol. The Interpol postmortem (PM) form has been analyzed, and a number of items in sections D and E thereof have been postulated to be suitable for documentation by CT data. CT scans have then been performed on forensic cases. Interpretation of the reconstructed images showed that indeed much of the postmortem information required for identification can be gathered from CT data. Further advantages of the proposed approach concern the observer independent documentation, the possibility to reconstruct a variety of images a long time after the event, the possibility to distribute the work by transmitting CT data digitally, and the reduction of time and specialists needed at the disaster site. We conclude that MSCT may be used as a valuable screening tool in DVI in the future.     

Forensic Archaeological Recovery of a Large‐Scale Mass Disaster Scene: Lessons Learned from Two Complex Recovery Operations at the World Trade Center Site

In 2006, unexpected discoveries of buried World Trade Center (WTC) debris and human remains were made at the World Trade Center mass disaster site. New York City's Office of Chief Medical Examiner (OCME) was given the task of systematically searching the site for any remaining victims' remains. The subsequent OCME assessment and archaeological excavation conducted from 2006 until 2013, resulted in the recovery of over 1,900 victims' remains. In addition, this operation demonstrated the essential skills archaeologists can provide in a mass disaster recovery operation. The OCME excavation data illustrates some of the challenges encountered during the original recovery effort of 2001/2002. It suggests that when understood within the larger site recovery context, certain fundamental components of the original recovery effort, such as operational priorities and activities in effect during the original recovery, directly or indirectly resulted in unsearched deposits that contained human remains.     

Indication and limitations of using palatal rugae for personal identification in edentulous cases

To explore the availability and the limitations of using the palatal rugae pattern in forensic practice for personal identification in edentulous cases, we set up an experiment, which involved 48 patients who had both old and new complete dentures and we observed their rugae. First, we made 48 pairs of maxillary casts from their old and new dentures and a further 50 maxillary casts from complete dentures at random, to use as variables. All the initial impressions taken from the mucosal surfaces of complete dentures were made from alginate impression materials, and the maxillary casts were made from hard dental plaster. Secondly, all 146 casts were trimmed so that all the areas except for the rugae area were removed. Subsequently, 50 examiners were given the 48 casts from the old dentures and were then asked to compare them with the other 98 casts for possible matches. The case numbers, which matched correctly, were recorded. The median percentage of correct matches among the 50 examiners was 94%, despite variations in their experience with forensic identification, and this accuracy does not differ significantly from that in dentate cases, as described in previous publications. The median percentage of correct matches among the 48 cases was 90%. Analyzing the incidence of obtaining a correct match in each case revealed that there were three major misleading shapes that could give rise to a low rate of correct matches; (1) severely low and poorly demarcated eminences of rugae, (2) change of palatal height, and (3) non-complex rugae pattern. These features are mainly due to the shape of the edentulous palate itself and rarely due to the dentures, and could lead to difficulties in finding unique points for use in matching rugae patterns. The results suggest that an appropriate selection of cases, taking into consideration the above misleading shapes, may establish an increased rate of accuracy for identification with this method, thereby bringing the percentage of correct matches closer to 100% in edentulous cases, which is also the percentage of correct matches previously reported in dentate cases.     

Diffuse vascular injury in fatal road traffic accident victims: its relationship to diffuse axonal injury

The authors have reported a macro- and microscopic study of brain lesions in 120 victims of fatal road traffic accidents, independent of the survival time. Diffuse vascular injury (DVI) was found in 14 patients (11.7%). All patients with DVI died within 24 h after the accident. The 14 patients with DVI also showed severe (Grade 2 or 3) diffuse axonal injury (DAI). Since DVI is restricted to road traffic accidents and incompatible with life, the high frequency observed in our series could be explained by the fact that all 120 patients were victims of road traffic accidents, and 69.2% had died within 24 h after the accident. The association between DVI and severe DAI (Grades 2 and 3) suggests that both lesions depend on the same mechanism, with the degree of axonal and vascular damage being determined by the intensity of the head acceleration. Our results show a relationship between DVI and DAI that suggest there may be a spectrum or at least a continuum between these entities as distinct from DVI being a separate entity.     

Denture marking--patient preference of various methods

Dental forensic organizations world wide have recommended that dental prostheses should be labeled with at least the patient's (wearer's) name and preferably with further unique identifiers such as social security number. A range of methods are available and the purpose of this study was to determine, via the means of a visual questionnaire, which are the most preferable to those patients who wear complete dentures. One hundred edentulous patients attending the Manchester Dental Hospital were shown a range of denture labeling methods and asked to rank these according to their preference. The most preferred method was that of an embedded radio frequency identification microchip (38% rated this as first) and the second was an inclusion technique using onion paper (24% rated this as first). The least preferred method was the use of a groove cut into the denture flange with 71% of patients rating this as the poorest in terms of esthetics. The study demonstrates that the method of denture labeling is important to patients and to ensure that denture labeling is performed routinely esthetic preferences must be considered.     

The Effects of Continuous Application of the TASER X26 Waveform on Sus scrofa,

This study investigated and evaluated the safety margins of the continuous long duration (up to 30 min) effect of the TASER X26 waveform, using a Sus scrofa model. Long duration continuous stimulus has not been evaluated on humans or human surrogates prior to this study. Swine were used as models due to similarities with humans in their skin and cardiovascular systems. Very long duration was used to determine both exposure dose and possible adverse physiological effects of dose. The trial began with an application of 10 min, and subsequent animals received increasing exposure time up to a survived maximum duration of 30 min. At the onset of this work, it was hypothesized that there would be a time limit after which most animals would not survive consistent with increased dose response. However, this hypothesis was not supported by the experimental results. All animals (10 of 10) survived up to 3 min. Seven of the 10 animals survived up to a 10‐min exposure and 3 of 5 animals with a 30‐min target exposure survived the full exposure. Surviving animals were recovered and observed for 24 h, with no postrecovery deaths. This suggests that swine (based on physiology) will not experience a fatal event when exposed to the TASER X26 for a continuous 3 min. Conclusions regarding longer duration (10–30 min) are not as certain due to the small sample sizes at these time intervals.