Effects of light-emitting diode photostimulation on burn wound healing

Annually, more than 1.2 million persons in the United States require medical care for burns. Healing of deep burn wounds requires restored perfusion and neoangiogenesis to reestablish blood flow and limit ischemic damage.\r\nWe propose that LED photostimulation, by inducing macrophage proliferation and secretion of pro-angiogenic factors, will restore perfusion by increasing angiogenesis. \r\nAn in vitro inflammatory model and in vivo rodent thermal injury model were treated with LED at 670nm, 730nm, 880nm, or combination-670nm/730nm/880nm. Conditioned media were analyzed for VEGF and NO. Excised burn wounds underwent measurement of surface area, tensile strength, VEGF, nitrites, and immunohistochemical markers (iNOS, VEGF, cyclooxygenase-2, Factor VIII, ED-1) on days 3, 7, and 14.\r\nBoth in vitro and in vivo findings demonstrate that LED therapy has vulnerary effects on angiogenesis, by affecting macrophage production of VEGF and NO. These effects are wavelength and fluence-dependent.\r\n