Study of bruise characteristics and evolution is of much interest in forensic sciences, with many objective techniques being researched. In this study we combine the optical methods of diffuse reflectance spectroscopy (DRS) and pulsed photothermal radiometry (PPTR) to measure signals from healthy and bruised skin. From these measurements we first obtain initial physiological parameters for a four-layer model of healthy skin near the bruised site. A bruise model is constructed by inserting a blood pool into this baseline model to simulate a bruise followed by bruise dynamics simulation for PPTR signals of bruises. Obtained bruise dynamics parameters describe the evolution of the bruise. The results show that the choice of a suitable healthy baseline affects bruise parameters obtained by fitting the simulated signals to the measurements. By using healthy skin baselines with similar melanin and papillary blood fractions during analysis, comparable bruise parameters are obtained. Differences in layer thickness and scattering properties of healthy skin did not significantly influence these parameters. In contrast, higher papillary blood content in one site resulted in considerably different bruise parameters. Our findings show the importance of good determination of a healthy baseline, preferably using the baseline obtained by a simultaneous fitting of multiple measurements.

Date Published: 22 July 2019
PDF: 7 pages
Proc. SPIE 11075, Novel Biophotonics Techniques and Applications V, 110751O (22 July 2019); doi: 10.1117/12.2527083

Published in SPIE Proceedings Vol. 11075:
Novel Biophotonics Techniques and Applications V
Arjen Amelink; Seemantini K. Nadkarni, Editor(s)