Larsen, Sara Tangmose4; Jensen, Karl Erik3; Villa, Chiara4; Lynnerup, Niels5
1 Section of Forensic Pathology, Department of Forensic Medicine, Faculty of Health and Medical Sciences, Københavns Universitet2 Unit of Forensic Anthropology, Department of Forensic Medicine, Faculty of Health and Medical Sciences, Københavns Universitet3 unknown4 Section of Forensic Pathology, Department of Forensic Medicine, Faculty of Health and Medical Sciences, Københavns Universitet5 Unit of Forensic Anthropology, Department of Forensic Medicine, Faculty of Health and Medical Sciences, Københavns Universitet
OBJECTIVES: As forensic age estimations in the living are performed without medical indication, there is a need for the development of non-ionizing methods. This study investigates the use of 1.0T MRI to visualize the ossification status of the medial end of the clavicle. MATERIAL AND METHODS: T2 weighted 3D images were collected from a 1.0T MR system. We prospectively scanned 102 subjects, 47 autopsy cases and 55 living volunteers (12-33 years). Images were scored in blind trials by three observers using a 4-stage system. Observers differed by level of training and radiological expertise. RESULTS: Motion artefacts reduced image resolution in living subjects. However, mean age at stage 4 was significantly different from mean age at stage 2 and 3. The minimum age at stage 4 was 19.8 years. Inter-observer agreement was moderate for autopsy cases and slight for living subjects. By contrasting subjects of "incomplete fusion" (≤ stage 3 on both sides) against "fused" (at least one stage 4), agreement rate rose to moderate (K=0.414) for living subjects. Despite the low agreement rate, no subject younger than 18 years was assessed as having "fused" clavicles. CONCLUSION: At lower image resolution, a 2-stage system increases agreements rates among observers. To further increase accuracy, clavicle staging needs to be performed by trained observers. If available, a 1.0T MR system may be used for age estimation in the living. However, further studies are needed to ensure that the ability to discriminate adults from minors, i.e. 18 years, is maintained.
Forensic Science International, 2014, Vol 234, p. 7-12
Adolescent; Adult; Age Determination by Skeleton; Analysis of Variance; Child; Clavicle; Female; Forensic Anthropology; Humans; Magnetic Resonance Imaging; Male; Observer Variation; Osteogenesis; Prospective Studies; Reproducibility of Results; Young Adult