The Effect of CO sub 2 Laser on Fibroblast Cultures

Surgeons, particularly in the field of otolaryngology/head and neck surgery, have been developing and refining applications for the carbon dioxide (CO2) laser for the past 10 to 15 years. During this time, many studies of CO2 laser wound healing have appeared, most comparing healing of laser and standard scalpel incisions. These reports consistently described delays in CO2 laser wound healing when compared to healing of scalpel incisions. Several studies involving skin wound tensile strength comparisons between scalpel and laser incisions in rats (6) and pigs (2,5) have shown that healing laser wounds are significantly weaker for several weeks post-incision. In a histologic comparison of laser and scalpel incisions in pigs, Norris and Mullarky (10) noted delayed collagen formation in laser incisions as compared to scalpel incisions. Using laser- and scalpel-cut explants taken from pig skin, Moreno et al (9) found that while epithelialization proceeded at the same rate from both types of explant, the onset of epithelialization from laser-cut explants was delayed. Despite this accumulation of information on CO2 laser wound healing, a good understanding of this topic as well as the effects of CO2 laser on cell growth and metabolism has not yet been achieved. Our study investigated the CO2 laser wound healing process by examining laser effects on fibroblasts, perhaps the most important cells involved in the wound healing process. Specifically, we studied the effect of noncytotoxic, defocused CO2 lasar energy, similar to that experienced by cells adjacent to a surgical laser wound, on proliferation of human dermal fibroblasts in culture.