Forensic imaging: New challenges for radiographers : B-588

Purpose: Cross-sectional imaging techniques have pioneered forensic medicine. The involvement of a radiographer and formation of "forensic radiographers" allows an improvement of the quality of radiological examinations and facilitates the implementation of techniques, such as sample collections, and the performance of post-mortem angiography. Methods and Materials: During a period of three months, five radiographers with clinical experience have undergone a special training in order to learn procedures dedicated to forensic imaging. These procedures involved: I). acquisition of MDCT data, II). sample collection for toxicological or histological analyses by performing CT-guided biopsies and liquid sampling, III). post-mortem angiography and IV). post-processing of all data acquired. To perform the post-mortem angiography, radiographers were in charge of the preparation of the perfusion device and the investigated body. Therefore, cannulas were inserted into the femoral vessels and connected to the machine. For angiography, the radiographers had to synchronize the perfusion with the CT-acquisitions. Results: All five radiographers have acquired new skills to become "forensic radiographers". They were able to perform post-mortem MDCT, sample collection, post-mortem angiography and post-processing of the acquired data all by themselves. Most problems have been observed concerning the preparation of the body for post-mortem angiography. Conclusion: Our experience shows that radiographers are able to perform high quality examinations after a short period of training. Their collaboration is well accepted by the forensic team and regarding the increase of radiological exams in forensic department, it would be nonsense to exclude radiographers from the forensic-radiological team.

Fitness to drive and cannabis: Experimental and real-life case study validation of two blood THCCOOH thresholds to distinguish occasional users from heavy smokers

Introduction: THC-COOH has been proposed as a criterion to help to distinguish between occasional from regular cannabis users. However, to date this indicator has not been adequately assessed under experimental and real-life conditions. Methods: We carried out a controlled administration study of smoked cannabis with a placebo. Twenty-three heavy smokers and 25 occasional smokers, between 18 and 30 years of age, participated in this study [Battistella G et al., PloS one. 2013;8(1):e52545]. We collected data from a second real case study performed with 146 traffic offenders' cases in which the whole blood cannabinoid concentrations and the frequency of cannabis use were known. Cannabinoid levels were determined in whole blood using tandem mass spectrometry methods. Results: Significantly high differences in THC-COOH concentrations were found between the two groups when measured during the screening visit, prior to the smoking session, and throughout the day of the experiment. Receiver operating characteristic (ROC) curves were determined and two threshold criteria were proposed in order to distinguish between these groups: a free THC-COOH concentration below 3 μg/L suggested an occasional consumption (≤ 1 joint/week) while a concentration higher than 40 μg/L corresponded to a heavy use (≥ 10 joints/month). These thresholds were successfully tested with the second real case study. The two thresholds were not challenged by the presence of ethanol (40% of cases) and of other therapeutic and illegal drugs (24%). These thresholds were also found to be consistent with previously published experimental data. Conclusion: We propose the following procedure that can be very useful in the Swiss context but also in other countries with similar traffic policies: If the whole blood THC-COOH concentration is higher than 40 μg/L, traffic offenders must be directed first and foremost toward medical assessment of their fitness to drive. This evaluation is not recommended if the THC-COOH concentration is lower than 3 μg/L. A THC-COOH level between these two thresholds can't be reliably interpreted. In such a case, further medical assessment and follow up of the fitness to drive are also suggested, but with lower priority.

Unconsciousness and sedation as precipitating factors of diabetic ketoacidosis.

The aim of this study was to identify medico-legal situations characterized by increased vitreous glucose concentrations, potentially lethal blood 3-hydroxybutyrate levels and conditions that could either incapacitate or lead to death on their own. The above was investigated in order to verify whether prolonged states of unconsciousness may play a role in precipitating diabetic ketoacidosis. Six groups of medico-legal situations (corresponding to 206 autopsy cases) were identified. Among these, three cases were characterized by pathologically increased vitreous glucose and blood 3-hydroxybutyrate levels. In one case diabetic ketoacidosis coexisted with underlying features that might have potentially incapacitated or lead to death on their own, whereas in two cases it corresponded with potentially lethal or lethal drug concentrations. The results of this study highlight the usefulness of systematically performing biochemistry in order to identify diabetic ketoacidosis-related deaths, even when autopsy and toxicology results provide apparently conclusive findings.

Usefulness of pericardial and pleural fluids for the postmortem diagnosis of sepsis.

The purpose of this study was to evaluate the postmortem distributions of procalcitonin (PCT), C-reactive protein (CRP), soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) and soluble interleukin-2 receptor (sIL-2R) levels in postmortem serum from femoral blood, pericardial fluid and pleural fluid in a series of sepsis-related fatalities (12 subjects) and control cases (20 subjects) that underwent medico-legal investigations. Our aim was to assess the diagnostic potential of the results obtained from pericardial and pleural fluid analysis in identifying sepsis-related deaths. All sepsis-related cases had a documented, clinical diagnosis that was established in vivo during hospitalization. Pneumonia was the main infectious focus identified during autopsy and histology. Pseudomonas aeruginosa, Klebsiella pnemoniae and Escherichia coli were the most commonly identified bacteria in blood and lung tissue cultures. The preliminary results corroborate the usefulness of PCT, CRP, sTREM-1 and sIL-2R determination in postmortem serum for the identification of sepsis-related deaths. Moreover, the data suggest that, as far as PCT, CRP, sTREM-1 and sIL-2R measurements are concerned, pericardial and pleural fluids can be considered suitable alternatives to postmortem serum should femoral blood prove unavailable at autopsy.

Interpretation of lesions of the cardiac conduction system in cocaine-related fatalities.

This study examines cases of chronic drug users who died suddenly after drug administration. Victims were young subjects, aged from 19 to 35 from Switzerland and known to the police as long-term drug users. The circumstances of death suggested the occurrence of a sudden, unexpected death. Some victims were undergoing methadone treatment. In each case, a forensic autopsy and toxicological analyses were performed at the Institute of Forensic Medicine in Lausanne in Switzerland between 2002 and 2004, including hair analysis as a means to establish chronic drug use in general, and cocaine use in particular. The conduction system was examined histologically and cases showing potentially lethal changes were chosen for this report. The most frequent lesions found were severe thickening of the atrioventricular node artery, intranodal and perinodal fibrosis, and microscopic foci of chronic inflammatory infiltration. The authors conclude that pathological lesions in the conduction tissue may play a role in the occurrence of death attributed to intoxication consecutive to cocaine ingestion.

Unplanned complex suicide by self-strangulation associated with multiple sharp force injuries: a case report.

In cases of ligature strangulation, the importance of distinguishing self-inflicted death from homicide is crucial. This entails objective scene investigation, autopsy and anamnesis in order to elucidate the manner of death correctly. The authors report a case of unplanned complex suicide by means of self-strangulation and multiple sharp force injury. The use of more than one suicide method, consecutively--termed unplanned complex suicide--gives this case particular significance. A brief discussion on this uncommon method of suicide is presented, particularly relevant to the attending forensic physician. In addition, a short overview of the entity of complex suicide is given.

Cardioinhibitory reflex due to a karate kick: a case report.

This article describes the case of a 17-year-old adolescent boy who received a foot kick in the trunk area from an expert in karate. He presented with immediate cardiocirculatory arrest. After a prolonged resuscitation, he was transferred to a hospital where he died 5 days later without ever regaining consciousness. Postmortem investigations including autopsy, radiology, histology, toxicology, and postmortem chemistry were performed that showed signs of multiple organ failure, an acute hemorrhage in the region of the celiac plexus, and signs of medical resuscitation. No preexisting disease, particularly those concerning the heart, was objectified. The cause of death was attributed to multiple organ failure after a prolonged cardiocirculatory arrest. Concerning the origin of the cardiac arrest, 2 hypotheses were considered-a cardioinhibitory reflex and a cardiac contusion (commotio cordis). Because of the presence of traumatic lesions in the celiac plexus, the first hypothesis was finally submitted. This case is reported because rare cases of sudden death from celiac reflex are described in the literature where it is almost impossible to find references with accurate documentation. The presented case confirms the importance of detailed documentation of the circumstances and postmortem investigations to establish a diagnosis of death due to cardioinhibitory reflex.

Education and Training in Forensic Intelligence: a New Challenge

From recent calls for positioning forensic scientists within the criminal justice system, but also policing and intelligence missions, this paper emphasizes the need for the development of educational and training programs in the area of forensic intelligence, It is argued that an imbalance exists between perceived and actual understanding of forensic intelligence by police and forensic science managers, and that this imbalance can only be overcome through education. The challenge for forensic intelligence education and training is therefore to devise programs that increase forensic intelligence awareness, firstly for managers to help prevent poor decisions on how to develop information processing. Two recent European courses are presented as examples of education offerings, along with lessons learned and suggested paths forward. It is concluded that the new focus on forensic intelligence could restore a pro-active approach to forensic science, better quantify its efficiency and let it get more involved in investigative and managerial decisions. A new educational challenge is opened to forensic science university programs around the world: to refocus criminal trace analysis on a more holistic security problem solving approach.

Fatal Cervical Spine Injury From Diving Accident.

Spinal cord injuries result after diving into shallow water, often after incautious jumps head first into water of unknown depth during recreational or sport activities. Mortality is generally due to upper cervical trauma. The authors present a case of a diving-related death in a young woman who underwent medicolegal investigations. The measured water depth at the supposed dive site was 1.40 m. Postmortem radiology and autopsy revealed fractures of the body and the posterior arch of the fifth cervical vertebra, a fracture of the right transverse process of the sixth cervical vertebra and hemorrhages involving the cervical paraspinal muscles. Neuropathology showed a posterior epidural hematoma involving the whole cervical region and a symmetric laceration of the spinal cord located at the fourth and fifth cervical vertebra level, surrounded by multiple petechial hemorrhages. Toxicology revealed the presence of ethanol in both blood and urine samples. The death was attributed to cervical spine fracture (C5-C6), spinal cord contusion, and subsequent drowning. This case highlights the usefulness of postmortem radiology, examination of the deep structures of the neck, toxicology, neuropathology, and a detailed research of signs of drowning to formulate appropriate hypotheses pertaining to the cause and mechanism of death.

Application of contrast media in post-mortem imaging (CT and MRI).

The application of contrast media in post-mortem radiology differs from clinical approaches in living patients. Post-mortem changes in the vascular system and the absence of blood flow lead to specific problems that have to be considered for the performance of post-mortem angiography. In addition, interpreting the images is challenging due to technique-related and post-mortem artefacts that have to be known and that are specific for each applied technique. Although the idea of injecting contrast media is old, classic methods are not simply transferable to modern radiological techniques in forensic medicine, as they are mostly dedicated to single-organ studies or applicable only shortly after death. With the introduction of modern imaging techniques, such as post-mortem computed tomography (PMCT) and post-mortem magnetic resonance (PMMR), to forensic death investigations, intensive research started to explore their advantages and limitations compared to conventional autopsy. PMCT has already become a routine investigation in several centres, and different techniques have been developed to better visualise the vascular system and organ parenchyma in PMCT. In contrast, the use of PMMR is still limited due to practical issues, and research is now starting in the field of PMMR angiography. This article gives an overview of the problems in post-mortem contrast media application, the various classic and modern techniques, and the issues to consider by using different media.

Cardiac Toxicity in Selective Serotonin Reuptake Inhibitor Users.

Several classes of recreational and prescription drugs have been associated with an increased risk of cardiovascular disease and the occurrence of arrhythmias, which may be involved in sudden deaths in chronic users even at therapeutic doses. The study presented herein focuses on pathological changes involving the heart, which may be caused by selective serotonin reuptake inhibitor use and their possible role in the occurrence of sudden cardiac death. A total of 40 cases were included in the study and were divided evenly into 2 groups: 20 cases of patients treated with selective serotonin reuptake inhibitors and 20 cases of sudden deaths involving patients void of any drug treatment. The first group included 16 patients treated with citalopram and 4 with sertraline. Autopsies, histology, biochemistry, and toxicology were performed in all cases. Pathological changes in selective serotonin reuptake inhibitor users consisted of various degrees of interstitial and perivascular fibrosis as well as a small degree of perineural fibrosis within the myocardium of the left ventricle. Within the limits of the small number of investigated cases, the results of this study seem to confirm former observations on this topic, suggesting that selective serotonin reuptake inhibitors may play a potential, causative role in the pathogenesis of sudden deaths in chronic users even at therapeutic concentrations.

Multiphase Postmortem Computed Tomography Angiography in Pediatrics: A Case Report.

Postmortem imaging techniques, especially postmortem computed tomography, have become integral tools in forensic investigations. Multiphase postmortem computed tomography angiography (MPMCTA) visualizes the vascular system in detail and makes it possible to evaluate the perfusion of even the smallest vessels. Although the technique has been well described for adults, no pediatric cases have been reported and no pediatric protocol has been established for this type of investigation. We present the case a 7-year-old child for which we used a previously described MPMCTA protocol and adapted values of perfusion, with the same technical equipment as for adult cases. Our main objective was to propose a perfusion protocol adapted for the investigation of infants and children. Moreover, we discuss both the difficulties that we encountered and possible ways to further improve the investigation of pediatric cases by MPMCTA.

Therapeutic and recreational methadone cardiotoxicity.

Several classes of drugs have been associated with an increased risk of cardiovascular disease and occurrence of arrhythmias potentially involved in sudden deaths in chronic users even at therapeutic doses. The study presented herein focuses on pathological changes involving the heart possibly due to methadone use. 60 cases were included in the study in total and were divided into three groups (therapeutic methadone users: 20 cases, recreational methadone users: 20 cases, and sudden death group in subjects who had never taken methadone: 20 cases). Autopsies, histology, biochemistry and toxicology were performed in all cases. Macroscopic and microscopic investigation results in therapeutic methadone users were similar to those observed in sudden, unexpected deaths in non-methadone users. In recreational methadone consumers, macroscopic and microscopic examination of the heart failed to provide results consistent with acute or chronic myocardial or coronary damage, thereby corroborating the hypothesis of death most likely following respiratory depression.

Symptoms of imbalance associated with cervical spine pathology

The goals of the present study are: to determine the prevalence of dizziness or imbalance in a population of patients with cervical-spine pathology as compared to that in the general population; to determine correlations between cervical spinal pathology and symptoms of dizziness or imbalance.

Loudness discomfort levels: A retrospective study comparing data from Pascoe (1988) and Washington University School of Medicine

Loudess discomfort levels (LDLs) were gathered from three Washington University School of Medicine sites, for a total of 325 subjects (total ears=454). These levels were compared to mean LDLs reported by Pascoe (1988). The results revealed that the mean LDL measured at WUSM (ie., the IHAFF procedure) is significantly different that the LDL reported by Pascoe (1988).