Noninvasive and real-time in vivo characterization of Inflammation skin. A feasibility of animal study.

Abstract

Inflammatory skin diseases were the most common problem in dermatology. This study aimed to develop a circuit by using a simple method for noninvasive, objective, and real-time skin inflammation screening. Sprague-Dawley rats were used in this study. The rats were chemically induced to suffer from skin inflammation at the back of their left-hand side while the right-hand side of their back remained untreated serving as a control. Impedance (Z) spectrum of the rat's skin was recorded. Two characteristic frequencies (4.5 and 48.3kHz) were found. At the two frequencies, the impedance of inflammatory skin tissue (ZIST ) was found to be significantly (P<.05) smaller than that of normal healthy skin tissue (ZNHST ). Moreover, the ratio of the impedance measured at 4.5kHz (Zf=4 .5kHz ) to the impedance measured at 48.3kHz (Zf=48.3kHz ), that is, Zf=4.5kHz /Zf=48.3kHz , was capable of skin inflammation screening. It was observed that the inflammatory skin tissue (IST) had the smaller value of Zf=4 .5kHz /Zf=48.3kHz (value<8.5) and normal healthy skin tissue (NHST) had the higher value of Zf=4 .5kHz /Zf=48.3kHz (value≈10) which almost remained constant. A circuit was developed which was used for measuring the skin impedance accurately at the two characteristic frequencies for skin inflammation screening.