Richard Bassed

Analysis of time of closure of the spheno-occipital synchondrosis using computed tomography.

Current knowledge concerning closure of the spheno-occipital synchondrosis is inadequate for age estimation purposes in that of the few detailed studies conducted, these demonstrate considerable variation concerning the age at which the synchondrosis commences and completes fusion, thus creating uncertainty for forensic investigators who may use this developmental feature for age determinations. The aim of the present study was to determine the sequence and timing of closure of the spheno-occipital synchondrosis for a large sample of a modern Australian population to assess if this age marker is a useful tool for age estimation for individuals around the age of 18 years. The sample consisted of 666 individuals in the age range 15-25 years, who were admitted to the Victorian Institute of Forensic Medicine (VIFM) mortuary and who had undergone routine full body multi-slice CT imaging. Results show that fusion was well underway by the age of 15 years and was complete by 17 years. Fusion begins superiorly and progresses inferiorly. Persistence of a scar at the site of fusion was demonstrated through to age 25 years. After the age of 16 years there was no significant difference in progress of fusion between males and females. The study showed that this age marker is of limited value for age estimations around the age of 18 years in this population.

Age estimation using CT imaging of the third molar tooth, the medial clavicular epiphysis, and the spheno-occipital synchondrosis: a multifactorial approach.

A multi-factorial method for estimating age was devised based on the development of the 3rd molar tooth, the medial clavicular epiphysis, and the spheno-occipital synchondrosis, using multiple regression as the means to construct age estimation formulae and CT scanning as the imaging modality. The sample consisted of approximately 600 individuals from a contemporary Australian population, between the ages of 15 and 25 years, who were admitted to the Victorian Institute of Forensic Medicine, Melbourne, Australia, for the purposes of medico-legal death investigation. Results show that the spheno-occipital synchondrosis does not contribute to the age estimation model for this age cohort. The regression computation for the 3rd molar tooth and medial clavicle, when combined into a single multiple regression calculation, provides a robust model with tighter age ranges at the 95% confidence interval (CI) than when each age marker is used individually. This research provides a method to estimate age for unknown age Australian individuals in the problematic age group of 15-25 years with greater precision than previously possible.

Forensic aspects of the 2009 Victorian Bushfires Disaster.

The 2009 Victorian Bushfires Disaster started on a record hot day in February 2009 and resulted in over 300 separate fires with a death toll of 173 and over 400 presentations to hospital emergency departments. This occurred a little over a week after a heat wave in which over 400 people were thought to have died prematurely in southeastern Australia. The Victorian Institute of Forensic Medicine in collaboration with the police force and the State Coroners Office and over 100 colleagues from all over Australia, Indonesia, New Zealand and Japan implemented a DVI process based on Interpol guidelines to identify the deceased persons. CT scanning was conducted on all remains collected and played a pivotal role in the identification processes in conjunction with experts in pathology, anthropology, forensic odontology and molecular biology. This paper outlines the scale of the disaster and the work, from a forensic medical perspective, to identify the deceased.

Age Estimation and the Developing Third Molar Tooth: An Analysis of an Australian Population Using Computed Tomography

Abstract:  The third molar tooth is one of the few anatomical sites available for age estimation of unknown age individuals in the late adolescent years. Computed tomography (CT) images were assessed in an Australian population aged from 15 to 25 years for development trends, particularly concerning age estimation at the child/adult transition point of 18 years. The CT images were also compared to conventional radiographs to assess the developmental scoring agreement between the two and it was found that agreement of Demirjian scores between the two imaging modalities was excellent. The relatively wide age ranges (mean ± 2SD) indicate that the third molar is not a precise tool for age estimation (age ranges of 3–8 years) but is, however, a useful tool for discriminating the adult/child transition age of 18 years. In the current study 100% of females and 96% of males with completed roots were over 18 years of age.

The use of computed tomography (CT) to estimate age in the 2009 Victorian Bushfire Victims: A case report §

The development of new imaging technologies is beginning to have an impact upon medico-legal death investigation in an increasing number of jurisdictions. Computed tomography (CT) is an imaging modality which is able to provide information to investigators without the need for a physically invasive autopsy in certain circumstances. The use of post-mortem CT as an aid to the identification of the victims of the Black Saturday bushfires is discussed with particular reference to dental age estimation. A case report is presented which demonstrates the ability of this imaging modality to separate individuals based upon dental development. Whilst CT is not yet able to adequately discriminate between differing restoration types and shapes, and therefore cannot be used for dental identification in the classic sense, the ability of this imaging modality to assess dental and skeletal development for the purpose of age estimation is valid.

Forensic medical lessons learned from the Victorian Bushfire Disaster: Recommendations from the Phase 5 debrief

The February 7th 2009 bushfires in Victoria, Australia, resulted in the deaths of 173 individuals, of whom 164 were included in the subsequent DVI operation. The final stage of the International DVI protocol is a debrief, referred to as Phase 5. The Phase 5 operational debrief process conducted in the wake of this disaster was designed for the purpose of developing new strategies in light of this experience. The agencies involved included the Coroners Court of Victoria, the Victorian Institute of Forensic Medicine, the Department of Justice, and Victoria Police. During the course of this debriefing process strategies and protocols were developed which aim to improve the capacity of all agencies to respond and resolve future incidents. This paper outlines the Phase 5 debrief carried out in the 6 months following the final coronial identification board, and details the findings and recommendations made by the agencies involved.

Advances in forensic age estimation

The ability to assign accurate age estimates to human remains and living individuals is becoming an increasingly important element of forensic practice. In mass fatality events, where many people lose their lives and are often unable to be visually identified, being able to separate individuals based on their age as determined by skeletal and/or dental development is a vital part of the Disaster Victim Identification (DVI) operation. For example, in the tragic bushfire disaster which struck Victoria in February 2009, of the 164 victims who lost their lives and were subject to the DVI process, 25 were under the age of 20 years, and many of these were located in commingled circumstances [1, 2]. Due to the severity of the fires and the condition of many of the remains it was only possible to identify a number of these by assessment of their age using dental and skeletal development [3]. Forensic age estimation also plays an increasingly important role in the assessment of living individuals of unknown age who have entered a foreign jurisdiction without identification papers, or with suspect identification documents. It is necessary to be able to determine the age status of these individuals for a number of reasons, including school entry and year level age requirements, and also for assessment of legal adulthood or childhood. Determination of an unknown age individual’s status as either an adult or a child is vital in terms of how that person will be treated by the law in not only criminal prosecutions, but also in immigration hearings, licensing applications and, increasingly importantly, determination of refugee status. Age assessment of living individuals is conducted by using various medical imaging modalities, such as conventional X-ray and CT scanning, in order to capture images of the developing skeleton and the dentition. The anatomical sites most commonly imaged are the hand/wrist region for assessment of skeletal development, the dentition for assessment of dental age, and more recently the use of CT scanning to capture images of the developing clavicle and the dentition [4, 5]. This imaging necessarily involves the use of ionising radiation with concomitant exposure to various tissues. This exposure is not at a level sufficient to cause immediate harm, but does raise the total lifetime dose of radiation experienced by the individual concerned. There are medical ethical and legal considerations involved in conducting radiological procedures on living people, with no definite medical need, that are yet to be properly addressed. In Australia and New Zealand, forensic odontologists and anthropologists have been using various age estimation methods for many decades, the majority of these developed from population studies originating in the United States, Canada, and Europe [6–9]. These methods were developed from research conducted many decades ago and on populations which geographically, environmentally, and nutritionally do not accurately reflect current population demographics. For juveniles, that is, those individuals under the age of 15 years, these systems, especially those describing dental development, have proven to be quite adequate and have served the profession well. Recent research, however, would suggest that for dental ageing at least, these older methods may not be as accurate as was once thought for young individuals [10], and it is suspected that they may be substantially more inaccurate for individuals older than 15 years of age. R. B. Bassed (&) Department of Forensic Medicine, Victorian Institute of Forensic Medicine, Monash University, 57-83 Kavanagh St, Southbank, Melbourne, Australia e-mail: richardb@vifm.org

Management of medicolegal natural deaths from hemopericardium or hemothorax using postmortem CT scanning

At the Victorian Institute of Forensic Medicine the forensic pathologist provides expert medical advice to the Coroner. Cases of natural death from hemopericardium and hemothorax are reasonably common in the forensic setting and are readily identifiable on postmortem CT (PMCT) scanning. The management of these cases raises interesting and challenging issues for the forensic pathologist. We present three cases in which PMCT angiography was useful in the management of each individual case and illustrate the potential of the technique in medico-legal death investigation.

The use of postmortem computed tomography in the diagnosis of intentional medication overdose

The recognition of a well defined basal layer of radio dense material on the postmortem computed tomography (CT) images, in the setting of typical scene findings of an intentional medication overdose and unremarkable external examination of the deceased’s body can, in certain circumstances, permit such cases to be managed without routine full autopsy examination. Preliminary toxicological analysis can be targeted to such cases to provide further supportive evidence of intentional medication overdose. In cases where the scene findings are ambiguous or have been contaminated the postmortem CT images may alert the pathologist of the possibility of overdose in an otherwise apparently natural death. We reviewed 61 cases of documented intentional therapeutic medication overdose and 61 control cases. In the majority of the cases of confirmed intentional therapeutic medication overdose the CT images showed no diagnostic features. However, in many cases a well defined basal layer of radio-opaque material was clearly seen to line the gastric mucosa. The postmortem CT pattern which we believe to be highly suggestive of intentional medication overdose must be differentiated from other causes of increased radio density in the stomach which include CT artefacts.

Identification of severely incinerated human remains: the need for a cooperative approach between forensic specialities. A case report.

Positive identification of incinerated human remains can be a perplexing problem, especially when there is no genetic material remaining for DNA analysis. This paper illustrates the importance of a multi-disciplinary approach to the identification of such remains, and explores the processes involved in the various effects of heat upon human bone and teeth, and the implications this has for positive identification. A case study is presented to illustrate the various problems encountered and the importance of discovering comprehensive ante-mortem records of the deceased. It is submitted that forensic odontologists and anthropologists be included in the body recovery process, both to maximise the recovery of evidence, and to ensure that all possible avenues for positive identification are explored, so as to avoid the need to rely upon the less robust method of circumstantial identification.