The effect of activated platelet rich plasma on the survival of grafted fat

Abstract

Fat graft has a very long history of use as a soft-tissue filler, but reports have demonstrated a variable degree of fat graft survival. Numerous processing methods have been proposed to achieve the goal of maximal survival. However, no definitive treatment to achieve this goal is available yet. Autologous platelet rich plasma (PRP) is a product derived from fresh whole blood that contains a high concentration of platelets with healing anti-inflammatory and proregenerative properties. The author’s hypothesis is that PRP could enhance the survival and quality of fat graft through its angiogenic effect. The scalp model of a nude mouse was applied. Twenty mice were randomly divided into two groups, with 10 rats in each group. The PRP group received fat mixed with PRP and then thrombin/CaCl2 mix was injected to activate PRP. The control group received fat mixed with saline. After 10 weeks, the mice were sacrificed and the fat pad was dissected and volume and weight measurements were performed. Light microscopical examination of the fat pad was performed. The histological parameters evaluated were as follows: presence of intact and nucleated fat cells; presence of cysts and vacuoles; inflammation, as evidenced by infiltration of lymphocytes and macrophages; vascularity; and presence of fibrosis. We could observe the increment of volume and weight of fat graft in the PRP group compared to the control group (t-test, p<0.05). Histologic evaluation of the grafts revealed significantly less cyst and vacuole formation in the PRP group (Mann-Whitney nonparametric test, p<0.05). Also, the PRP group showed more vascularity and less fibrosis compared to the control group (p<0.05). However, the cellular integrity of fat cell and inflammation within the specimen did not achieve statistical difference in the PRP and control groups. PRP treatment could improve the survival and quality of fat graft which was confirmed by volume and weight measurement and histological evaluation.