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Virtual anthropology is made possible by modern cross-sectional imaging. Multislice CT (MSCT) can be used for comparative bone and dental identification, reconstructive identification and lesion identification. Comparative identification, the comparison of ante-and post-mortem imaging data, can be performed on both teeth and bones. Reconstructive identification, a considerable challenge for the radiologist, identifies the deceased by determining sex, geographical origin, stature and age at death. Lesion identification combines virtual autopsy and virtual anthropology. MSCT can be useful in palaeopathology, seeking arthropathy, infection, oral pathology, trauma, tumours, haematological disorders, stress indicators or occupational stress in bones and teeth. We examine some of the possibilities offered by this new radiological subspeciality that adds a new dimension to the work of the forensic radiologist. A multidisciplinary approach is crucial and involves communication and data exchange between radiologists, forensic pathologists, anthropologists and radiographers.Virtual autopsies are currently becoming increasingly common worldwide in forensic medicine.1 Use of multislice CT (MSCT) or multidetector CT (MDCT) before classic medicolegal autopsy gives the forensic pathologist considerable information on injuries and cause of death.2 A recent advance in forensic imaging is post-mortem CT angiography, which yields further information on soft tissues and visceral and vascular injuries. Modern cross-sectional imaging can be used in virtual anthropological studies as well as in virtual autopsy. 4 In biological anthropology, it can be applied to compare bone or dental criteria between species. An important application is forensic anthropology, to obtain positive identification of an unknown decedent. The introduction of imaging in anthropology is of course not new, and many radiographic applications have been already described and published.In virtual anthropology, teeth and bones can be studied by MRI or by MSCT. MRI has numerous applications, 5,6 and it will certainly become an important tool in forensic study of the living, particularly for age assessment. This technique presents many advantages compared with MSCT, and, like ultrasound, it is X-ray free. However, access to MRI in thanatology is currently difficult, mainly because of limited time availability of the machine.The wide range of possibilities offered by MSCT may seem bewildering to a non-radiologist! If an MSCT examination is to give optimal results, many technical conditions must be adhered to in terms of image quality, spatial resolution and contrast. If not, the final images may even be unusable, in particular, for analysis of fine trabecular bone lesions (Figure 1). The initial CTmust be performed with appropriate voltage, amperage, field of view and slice thickness. After acquisition, reconstruction time is critical. Choice of thickness and interval and choice of filters influence voxel size and the possibility of radiological interpretation...

Purpose: To determine if postmortem computed tomography (CT) and postmortem CT angiography help to detect more lesions than autopsy in postmortem examinations, to evaluate the strengths and weaknesses of each method, and to define their indications. Materials and Methods:Postmortem CT angiography was performed on 500 human corpses and followed by conventional autopsy. Nine centers were involved. All CT images were read by an experienced team including one forensic pathologist and one radiologist, blinded to the autopsy results. All findings were recorded for each method and categorized by anatomic structure (bone, organ parenchyma, soft tissue, and vascular) and relative importance in the forensic case (essential, useful, and unimportant).

Modern post-mortem investigations use an increasing number of digital imaging methods, which can be collected under the term “post-mortem imaging”. Most methods of forensic imaging are from the radiology field and are therefore techniques that show the interior of the body with technologies such as X-ray or magnetic resonance imaging. To digitally image the surface of the body, other techniques are regularly applied, e.g. three-dimensional (3D) surface scanning (3DSS) or photogrammetry. Today's most frequently used techniques include post-mortem computed tomography (PMCT), post-mortem magnetic resonance imaging (PMMR), post-mortem computed tomographic angiography (PMCTA) and 3DSS or photogrammetry. Each of these methods has specific advantages and limitations. Therefore, the indications for using each method are different. While PMCT gives a rapid overview of the interior of the body and depicts the skeletal system and radiopaque foreign bodies, PMMR allows investigation of soft tissues and parenchymal organs. PMCTA is the method of choice for viewing the vascular system and detecting sources of bleeding. However, none of those radiological methods allow a detailed digital view of the body's surface, which makes 3DSS the best choice for such a purpose. If 3D surface scanners are not available, photogrammetry is an alternative. This review article gives an overview of different imaging techniques and explains their applications, advantages and limitations. We hope it will improve understanding of the methods.

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Thanks to recent advances, computed tomography is now seen as a tool of great value in the field of physical anthropology. In this study, we focused on the posterior pelvis and the auricular surface and evaluated the accuracy of 3D reconstructions of the auricular surface, using a methodology derived from a previous study by Lovejoy et al. We also looked for trabecular bone criteria expressing age-related changes. Forty-six coxal bones were scanned, and scoring of macroscopic criteria showed a good agreement between 3D reconstructions and photographs, especially for transverse organization (k = 0.90). The changes occurring in the posterior part of the sacropubic trabecular bundle were evaluated on CT reconstructions via three new criteria, which exhibited a good intra- and inter-observer agreement (k = 0.77-0.89), and were particularly useful in identifying older subjects. We concluded that these CT-evaluated trabecular bone criteria are promising and yield useful information about age at death.

Historically, radiographical identification has been done by comparing conventional antemortem and postmortem X-ray images. The advent of new technologies such as multislice computed tomography (MSCT) is making traditional antemortem examination increasingly less frequent. The authors present the results of MSCT study of 35 corpses, which demonstrated features potentially useful for identification purposes in ten cases. These features, which relate to abnormalities of postcranial bone as well as of the internal organs, are presented. Attempts were made to find any antemortem X-rays or MSCTs on the cases described to compare the two antemortem and postmortem images. Although antemortem imaging was recovered for only two cases (one case with a skeletal abnormality and one case with a visceral abnormality), it permitted for both cases the comparison of antemortem and postmortem MSCTs.

Age estimation of living individuals is of critical importance in forensic practice, especially because of the increased migration in developed countries. Recently, the contribution of magnetic resonance imaging (MRI) to age evaluation has been studied, as it seems to be an efficient technique to analyze growth plate maturation and epiphyseal fusion. We developed an MRI staging system for the distal tibial epiphysis and the calcaneal epiphysis and evaluated its reliability on 180 MRI scans of the ankle and foot in a sample of individuals aged from 8 to 25 years old. For both bones, the degree of union between the metaphysis and epiphysis was classified in three stages. Intra- and inter-observer variabilities were good, showing the validity and reproducibility of the method. Our results were consistent with data in the literature indicating that both epiphyses mature earlier in females than in males. Bayesian predictive probabilities were used to assess the validity of our method in estimating the age of an individual in relation to the 18-year threshold. MRI of the ankle and foot can be used in association with other methods to estimate age in living individuals.