Effects of continuous-wave (670-nm) red light on wound healing.

BACKGROUND Recent work suggests that injuries can heal faster if treated by lasers emitting 670-nm red light. LED lights emitting 670-nm light are now available. This suggests that inexpensive and easy-to-use 670-nm LED lights might help accelerate cutaneous wound healing. OBJECTIVE The objective was to evaluate the effect of 670-nm LED light on wound healing in SKH-1 hairless mice. METHODS To study 670-nm light effects on incisional injury, animals were left unexposed or exposed to equal doses of high-, medium-, or low-flux light. Burn injuries were treated with high-flux light or left unexposed. Healing was assessed by measurement of the burn area and the gap remaining to closure of incisional injury. RESULTS Mice exposed to 670-nm red light showed significantly faster healing than control mice. High, medium, and low fluxes of light were all effective after incisional injury. In burn injury, there was improvement in wound healing initially, but the time to repair was unchanged. CONCLUSIONS A 670-nm LED red light source accelerates healing in skin of SKH-1 hairless mice after incisional injuries, but is not as effective for burn injuries. These data that suggest red light exposure may be helpful in postoperative wound repair.