Enhancing Fat Graft Survival With Autologous Growth Factors: Platelet-Rich Fibrin (PRF) vs Platelet-Rich Plasma (PRP).

We read with interest Yu et al’s[1] preclinical study on the effect of platelet-rich fibrin (PRF) on fat-grafting volume and viability in nude mice. The poor survival of adipocytes and adipose-derived stem cells within fat grafts hinders the use of fat grafting in all clinical settings. We commend the authors on their methodologically robust study design, which was well powered (n = 120), included randomization, and used appropriate histologic stains for adipocyte viability among others.

The authors discuss how PRF may be a superior adjunct for increasing fat graft survival than other autologous sources of growth factors (eg platelet-rich plasma [PRP]). This is based on the finding that PRF releases proangiogenic growth factors over a longer time period (14-20 days).[2] We disagree that this is preferable. It has been well established by Eto et al[3] that, in mice, adipocytes located more than 300 μm from the periphery of the fat graft become nonviable in just 24 hours. Therefore any adjunct must act very rapidly, and our opinion is that a prolonged delivery of growth factors after this 24-hour window will do nothing for nonviable adipocytes. Theory aside, it would be interesting to see PRF and PRP compared directly in a similar animal study, to determine if one has a superior effect on fat graft survival/viability. To date there has only been 1 study comparing PRF and PRP directly, and this found no difference; [4] however, that study was insufficiently powered (n = 20) to identify small differences.