Vascular patterns in mature hypertrophic burn scars treated with fractional CO2 laser

ABSTRACT Background and Objective Fractional CO 2 laser has recently emerged as a promising therapeutic modality to improve the texture and appearance of burn scars. An issue in many burn scars is persistent erythema, which traditionally has been treated with vascular lasers. Interestingly, fractional CO 2 lasers have been shown to improve the appearance of burn scars, including erythema, but no mechanism has been proposed for this change. Our objective is to evaluate the histopathologic changes in vasculature in burn scars treated with fractionated CO 2 laser, and to attempt to describe the mechanism behind reduced erythema following treatment. Study Design/Materials and Methods Uncontrolled, prospective study of ten patients with mature burn scars, from a clinical and histological perspective. Biopsy specimens were obtained before and 2 months after 3 treatment sessions. Anti‐CD31 immunostaining was performed to highlight vascular patterns in biopsy specimens. Results In histological analysis, an increase in vascular density, particularly of small caliber vessels, was seen following treatment, with an 82.6% average increase in vasculature ( P = 0.028). This increase in vascularity correlated with a decrease in clinical erythema and vascularity scores, measured using the Vancouver Scar Scale. Conclusion Mature hypertrophic burn scars treated with a fractional CO 2 laser showed a statistically significant increase in vascular density in the superficial dermis. A non‐statistical decrease in clinically perceived erythema and improvement of overall appearance was seen. To our knowledge, this is the first report of increased vascular density in burn scars treated with fractional CO 2 laser and suggests our prior assumptions on causes of erythema in mature hypertrophic scars may need to be challenged. Lasers Surg. Med. 46:597–600, 2014. © 2014 Wiley Periodicals, Inc.