Development of a Patch-Type Sensor for Skin Using Laser Irradiation Based on Tissue Impedance for Diagnosis and Treatment of Pressure Ulcer

Pressure ulcer is a disease that has been increasing rapidly worldwide in recent years following the growing elderly population. However, its diagnoses and treatments still depend on the naked eye and traditional drug treatments, respectively. In this study, we examined the effects of the pressure ulcer-induced regions based on impedance measurements and skin electrical signals, and its treatment efficacy was verified using photobiomodulation therapy. The light used in this therapy was a light emitting diode light (660 nm), and it was verified to enhance antioxidant capacity in the enzyme-based antioxidation process. An examination of the angiogenesis efficacy based on wound healing activity and tube formation activation at the cell level confirmed that photobiomodulation therapy accelerated wound healing and angiogenesis. When the treatment effect of the therapy was evaluated with a rat animal model of pressure ulcer, the region affected by the pressure ulcer and the infiltration of inflammatory cells were significantly reduced by photobiomodulation therapy. The diagnosis using skin impedance measurement showed differences in the region affected by the pressure ulcer. The results of this study confirmed the diagnosis based on the impedance and treatment efficacy of photobiomodulation therapy and the treatment of pressure ulcer. The use of photobiomodulation therapy in conjunction with the existing treatment methods is expected to improve the efficiency of the pressure ulcer treatment.