The systemic effect of 830-nm LED phototherapy on the wound healing of burn injuries: A controlled study in mouse and rat models

Abstract

Background: The present controlled study assessed the systemic effect of 830-nm LED phototherapy in rodent models. Materials and methods: Two HR-1 hairless mice and 3 HWY/Slc hairless rats were divided into two groups: the treatment group (Tx Group, one mouse, two rats) and the control group (Con Group, one mouse, one rat). All animals received an identical 12 mm × 12 mm control burn over three sites on the dorsum with a fractional ablative CO2 laser. Wounds were protected with a film-type dressing. The abdomen of the Tx Group subjects was irradiated with an 830-nm LED array immediately post CO2 treatment and then at 1, 5 and 6 days post laser irradiation. Wound healing was assessed macroscopically from the clinical photography. Results: At the 2-day post-laser assessment, the healing process in the wounds in the Tx Group was already apparent compared with the Con Group. At the final evaluation (post-burn day 7), no site on the Con Group (six wounds) showed 100% healing, recovery was over 70% in four and lower than 50% in two sites. Of the nine Tx Group sites, 100% recovery was seen in three sites, over 70% in five sites and one wound was exacerbated through trauma. Conclusions: LED phototherapy on the abdomen produced faster wound healing of the uniform burn wounds than in animals with the same burn wounds that did not receive LED phototherapy, strongly suggesting the systemic effect of phototherapy.