Effect of ultraviolet therapy on rat skin wound healing.

Ultraviolet (UV) light therapy has been suggested as a treatment for pressure sores and crural ulcerations even though controlled trials are few. Therefore, the effect of UV light therapy on wound healing was studied in rat skin. A dose-dependent, significant improvement in the diminution of wound size was found between 4 and 15 days in wounds treated with UV as compared with untreated control wounds in the opposite side of the same animals. Wound closure, however, did not occur earlier in the treated wounds. UV had a marked warming effect; warmth alone without UV had no effect on wound healing. No significant difference was found in the tensile strength of UV-treated wounds at 7 and 15 days when compared with untreated wounds. Moreover, the intensity of the inflammation was equal in both treated and control wounds when studied histologically. We did not find any effect on clinical infection rate or bacterial colonization of the wounds. Although UV therapy seems to have an effect on wound healing in rat skin the present results are rather nonsupportive of the clinical benefits that are expected from this kind of treatment.