Mechanical Micronization of Lipoaspirates Combined with Fractional CO₂ Laser for the Treatment of Hypertrophic Scars

Background:Treating hypertrophic scars remains challenging. Stromal vascular fraction (SVF) gel is produced by a purely mechanical process from lipoaspirates, rich in adipose-derived stem cells, and has showed therapeutic potential on scars. However, controversial effects on hypertrophic scars are emerging. This study aimed to assess the therapeutic effects of SVF gel combined with fractional CO2 laser on hypertrophic scars. Methods:A rabbit ear hypertrophic scar model was established. SVF gel combined with fractional CO2 laser was conducted for hypertrophic scars in rabbits. Scar alleviation in rabbits was observed based on the appearance and histology of scars, and the underlying mechanism was investigated by tissue immunologic analyses and quantitative real time polymerase chain reaction. At last, six patients with hypertrophic scar were treated by SVF gel combined with fractional CO2 laser. Therapeutic effects were assessed using the Vancouver Scar Scale. Results:Following the treatments, hypertrophic scars became less apparent and softer, the dermis became thinner, and collagen fibers appeared looser and arranged in a more organized pattern. The SVF gel plus fractional CO2 laser group showed the most obvious improvement. In addition, SVF gel combined with fractional CO2 laser increased adipogenesis in scar tissue, and adipose tissue regeneration was observed. Hypertrophic scars in patients were alleviated after treatment with SVF gel combined with fractional CO2 laser. Conclusions:SVF gel transplantation combined with fractional CO2 laser showed encouraging therapeutic effects on hypertrophic scars. Although further investigation is necessary, this technique has great potential for clinical application to treat hypertrophic scars.