(Georgia Institute of Technology, 2008)
Duckworth, Mark G.; Caspall, Jayme J.; Mappus IV, Rudolph L.; Kong, Linghua; Yi, Dingrong; Sprigle, Stephen
During investigations of potential child and elder abuse, clinicians and forensic practitioners are often
asked to offer opinions about the age of a bruise. A commonality between existing methods of bruise aging
is analysis of bruise color or estimation of chromophore concentration. Relative chromophore concentration
is an underlying factor that determines bruise color. We investigate a method of chromophore concentration
estimation that can be employed in a handheld imaging spectrometer with a small number of wavelengths.
The method, based on absorbance properties defined by Beer-Lambert's law, allows estimation of
differential chromophore concentration between bruised and normal skin. Absorption coefficient data for
each chromophore are required to make the estimation. Two different sources of this data are used in the
analysis- generated using Independent Component Analysis and taken from published values. Differential
concentration values over time, generated using both sources, show correlation to published models of
bruise color change over time and total chromophore concentration over time.