Early assessment of burn severity in human tissue ex vivo with multi-wavelength spatial frequency domain imaging

Early knowledge about burn severity and depth can lead to improved outcome for patients. In this study, we investigated the change in optical properties in ex vivo human skin following thermal burn injuries. Human skin removed during body contouring procedures was subjected to thermal burn injury for either 10 or 60 s. Multi-wavelength spatial frequency domain imaging (SFDI) measurements were performed on each sample and the optical properties (absorption and scattering parameters) were obtained at each wavelength. Multi-wavelength fitting was used to quantify absorption and scattering parameters, and these parameters were compared to histologic assessments of burn depth related to burn severity. Our results indicated substantial changes in optical scattering parameters and these changes correlated well with the burn severity and depth, and fit closely with previously reported studies using porcine in vivo models. This study provides the characterization of thermal burn injury on human skin ex vivo by using the optical method of SFDI with high sensitivity and specificity. This preclinical human model system without live animals could have uses in testing the imaging parameters of other skin injuries, including from caustic agents.