Forensic 3D Documentation of Skin Injuries

Abstract

An accurate and precise documentation of injuries is fundamental in a forensic pathological context. Photographs and manual measurements are taken of all injuries during autopsies, but ordinary photography projects a 3D wound on a 2D space. Using technologies such as photogrammetry, it is possible to create 3D detailed, to-scale, true-color documentation of skin injuries from 2D pictures. A comparison between the measurements of 165 lesions taken during autopsies and on photogrammetrically processed pictures was performed. Different types of lesions were considered: 38 blunt force injuries, 58 sharp force injuries, and 69 gunshot injuries. In all cases, very low differences were found with mean ≤ 0.06 cm and median ≤ 0.04 cm; a mean difference of 0.13 cm was found for the blunt force injuries. Wilcoxon signed-rank test showed no statistically significant differences between the two measurement methods (p > 0.05). The results of intra- and inter-observer tests indicated perfect agreement between the observers with mean value differences of ≤ 0.02 cm. This study demonstrated the validity of using photogrammetry for documentation of injuries in a forensic pathological context. Importantly, photogrammetry provides a permanent 3D documentation of the injuries that can be reassessed with great accuracy at any time. Such 3D models may also be combined with 3D reconstruction obtained from post-mortem CT scans for a comprehensive documentation of the lesion (internal and external information) and ultimately used for virtual reconstruction.

Reference

Villa, C. (2016). Forensic 3D documentation of skin injuries. International Journal of Legal Medicine. doi:10.1007/s00414-016-1499-9