To Evaluate the Photo-activation Effect on Human Foot Under Near- or Far- Infrared Illumination by Using a Novel 2D Oxygen Saturation Image

The oxygen saturation value is an important indicator for health assessment of peripheral circulation, especially for the diabetic and hemodialysis patients. The infrared light was usually used to promote the expansion of micro vessels and improve the blood circulation rate of the human body. However, the traditional method to improve the blood circulation may cause the skin burning, and the evaluation of peripheral circulation status needed to wait a period instead of a real-time method. Therefore, the two-dimensional oxygen saturation (SpO2) image was presented in this study, and which was employed to observe the human foot's oxygen saturation and analyze photo-activation effect irradiated by near- or far- infrared light (NIR and FIR). The results showed that the blood circulation and the SpO2 can be enhanced by both near- and far- infrared irradiation. The near infrared light could enhance the SpO2 of foot in a short time, and the mildly far infrared light can provide the long-term enhancing effect. The suitable parameter was 17 mW/cm
²
with more than 30 minutes FIR irradiation for continuously Sp02 enhanced. This research had successfully presented a two-dimensional image and visual method to observe the Sp02 variation and find the suitable parameters for enhancing the Sp02, which can apply in clinical light therapy, promotion of blood circulation during hemodialysis and related applications.