Autologous chyle fat grafting for the treatment of hypertrophic scars and scar-related conditions

Abstract Background Scarring is the product of natural restoration, yet its treatment remains challenging. Both collagen and fibroblasts are abnormally abundant in scars, leading to scar hyperplasia or contracture. Several clinical studies have reported that wrinkles at the recipient site are reduced, pores are narrowed, pigmentation is decreased, and skin is softened after autologous fat transplantation. In this study, we investigated the ability of autologous chyle fat injection to normalize the fibroblasts and collagen of scar tissue in 80 adult patients with hypertrophic scars resulting from severe burns received more than 1 year previously. Methods The patients underwent autologous chyle fat injection, and scar samples were collected at different time points. Differences in the number of adipocytes before and after chylosis were assessed by cell culture, and changes in the structural organization of the scars were detected via histologic and immunohistochemical analyses. Results After preparation, the chyle fat contained few autologous adipocytes and large amounts of extracellular matrix. Following the injection of chyle fat, the thickness, color, and elasticity of hypertrophic scar tissue tended toward normalization, and patient satisfaction increased. The three adipose tissue donor sites used for the preparation of chyle fat were the abdomen, buttocks, and inner thigh, of which the inner thigh yielded the best therapeutic outcomes. The density and quantity of fibroblasts in the scars decreased following the injection of chyle fat, and the arrangement, quantity, and shape of type III collagen fibers tended toward normalization. After three treatments, the results of immunohistochemical staining showed that type III collagen was significantly less abundant than before treatment. Conclusions Autologous chyle fat transplantation has a good therapeutic effect on hypertrophic scar tissue. The injection of chyle fat into hypertrophic scar tissue reduced the density and quantity of fibroblasts and prompted the arrangement, quantity, and shape of type III collagen to normalize.