Objective: To perform quantitative observation on the color change of local skin after cupping, so as to explore objective and quantitative methods for skin response of cupping.
Methods: Seven health subjects were included. By quantitative meridian cupping instrument, cupping methods with four types of pressures were respectively performed on subjects for 5 min.The spectrum of cupping mark before and after the cupping was collected by hyperspectral camera, and the color change was recorded by digital camera.
Results: Before the cupping, the differences of back skin areas were not significant (P>0.05), and its average spectrum indicated two peaks at 540-550 nm and 580-590 nm. After cupping with different pressures, spectrum changes of skin were observed. For -0.02 MPa, the most significant reduction was observed at 550 nm (-12.1%, P<0.05); for -0.03 MPa, the most significant reduction was observed at 540 nm (-22.1%, P<0.05); for -0.04 MPa, the most significant reduction was observed at 610 nm (-26.7%, P<0.05); for -0.05 MPa, the most significant reduction was observed at several spectrums (all P<0.05).
Conclusions: After cupping with different negative pressures, significant changes of spectrum are observed on skin; for different pressures, the spectrums of the most significant changes are different; the hyperspectral camera could be applied to perform quantitative observation on the color change of local skin.
Keywords: cupping; cupping mark; hyperspectral camera; skin; spectrum.