WOUND-HEALING AFTER LASER INJURY TO SKIN - THE EFFECT OF OCCLUSION AND VITAMIN-E

The skin of Yorkshire pigs was irradiated with various doses of argon and copper-vapor laser and evaluated for effects on healing time of pretreatment with topical or intramuscular vitamin E or the Op-Site wound dressing. Incident irradiance for both lasers was between 3.5 and 4.5 W/cm(2) for a 10-14-mm beam diameter with a nearly uniform intensity profile. Minimal erythemic dose for the copper-vapor laser was 35 +/- 2 J/cm(2) (10 s exposure) and 22.4 +/- 0.1 J/cm(2) (6-s exposure) for the argon laser. Three dose levels were administered: a low dose causing light erythema, an intermediate dose, and a high dose causing dermal stasis. The radiant exposures far low, intermediate, and high doses were 35, 70, and 138 J/cm(2) for the copper-vapor laser and 22.4, 55, and 129 J/cm(2) for the argon laser. Exposure to argon and copper-vapor lasers generally caused wounds with similar healing times. Healing time was significantly decreased for wounds caused by intermediate exposure of the copper-vapor laser and either pretreated with vitamin E or treated with the wound dressing. Healing times for corresponding argon-laser exposure were significantly decreased with pretreatment of intramuscular vitamin E only or after treatment with the wound dressing. These findings may be valuable in selecting treatment for accidental laser skin injuries in man.