The Effect of Stromal Vascular Fraction on Scar Formation of Transverse Rectus Abdominis Muscle Flap Donor Sites: A Pilot Study

Abstract

Background: Stromal vascular fraction (SVF), which plays a substantial role in wound healing, has been discussed in many recent studies concerning its positive effect on scar formation. Our study explored the effects of SVF on scar formation from partially-removed transverse rectus abdominis muscle (TRAM) flaps after inset.Methods: From December 2017 to May 2020, we enrolled 11 patients undergoing breast reconstruction performed by a single surgeon using the free TRAM flap. As a split-body, placebo-controlled study, SVF was subcutaneously injected into one side of the abdomen, and normal saline was injected into the other side of each patient. Scarring was evaluated using the Vancouver Scar Scale (VSS) and Patient Scar Assessment Questionnaire (PSAQ) at 1, 6, and 12 months after surgery, and histology was evaluated with immunofluorescence analysis at 6 months after surgery.Results: No statistically significant differences were noted in the total scores or subcategory score of the VSS and PSAQ between the test and control groups. Some patients showed more positive staining for alpha smooth muscle actin, collagen type I, and type III in the test group than in the control group. However, quantification of positively stained areas showed no statistically significant difference.Conclusion: Intraoperative SVF injection had no demonstrable clinical effect on scar quality. Histology with immunofluorescence analysis also failed to demonstrate any significant effect of SVF on scars at the microscopic level. Despite previous studies indicating the positive effects of SVF on scar quality, this pilot study questions its true effectiveness.