Laser Acupuncture Improves Skin Color Deformation by Cupping: A Pilot Study

Abstract

Negative pressure of cupping induces skin deformation such as ecchymosis and purpura in a circular shape. Thus, there is a desire to treat skin before depigmentation and scarring occurs. Therefore, we introduce laser therapy, a widely used technique treat pigmentation in dermatology. Various parameters of laser therapy can be applied, so to determine the optimal exposure parameters that do not damage the surrounding tissues, the subjects were divided into four groups: a non-stimulation group and three laser groups (4 J/cm² group, 6 J/cm² group, and 8 J/cm² group). We selected the wavelength and output of laser as follows: 660nm and 50mW. The 40 were divided into four groups of 10. In the first experiment, we measured skin temperature using Digital infrared thermography in order to observe whether the laser could cause heat damage. In the second experiment, each group received the assigned laser therapy protocol every 24 hours for 72 hours. We obtained a skin image using a cross polarization technique. Previous studies have shown that a^* and E.I (erythema index) represent the degree of skin erythema (hemoglobin content). M.I (melanin index) indicates the degree of skin pigmentation (melanin content). Hence, skin color information was analyzed with the a^*, erythema index (E.I), and melanin index (M.I) for 72 hours. None of the laser exposure parameters led to skin damage by heating or energy dissipation. The results of a^*, E.I, and M.I of all groups showed the different recovery rates towards the normal skin color information before cupping. As energy density increases, the result of a^* and E.I showed the fast recovery rate. There was no significant different between M.I at non-stimulation group and M.I at 4 J/cm². Therefore, the least energy density as 6 J/cm² is need for the recovery of melanin content. The a^*, E.I, and M.I at 8 J/cm² group rather than other groups were significantly recovered to normal skin color. In conclusion, the laser therapy (energy density: 8 J/cm²) has a significant recovery of the skin erythema and skin pigmentation except to skin damage.