Current concepts of fat graft survival: histology of aspirated adipose tissue and review of the literature.

BACKGROUND Controversy remains about the longevity of correction in autologous fat grafts and its relation to adipocyte survival. Reported long-term fat graft survival rates differ widely, depending on harvesting method, means of reinjection, injection site, and evaluation methods. OBJECTIVE To demonstrate histologic findings of aspirated adipose tissue and compare the findings to the reports in the literature. METHODS Review of the literature and the histology of transplanted fat 7 years after subcutaneous implantation and trypan blue staining to determine the vitality of defrosted adipocytes. RESULTS Fat cells survive aspiration with a suction machine or syringe equally well. Use of a liposuction cannula or 14-gauge needle gives comparable results. Local anesthesia or tumescent local anesthesia is recommended for the donor site, preferably with addition of epinephrine. CONCLUSION Clinical longevity of correction after autologous fat transfer is determined by the degree of augmentation resulting from the amount of fibrosis induced and the number of viable fat cells. Survival of aspirated fat cell grafts depends mainly on the anatomic site, the mobility and vascularity of the recipient tissue, or underlying causes and diseases, and less on harvesting and reinjection methods.