Facial fat transfer: how much remains? Three discrepancies leading to regret

Regret often stems from the variability in how much fat persists. In a review of temple injections, some reports showed 65.7% retention, while others showed 33% on one side and 32% on the other—reflecting wide variation.[1]Please understand in advance that even the same surgical procedure can produce a wide range of results.

Discrepancy 1: The retained volume is difficult to interpret

The retained volume varies depending on the anatomical site, treatment method, and surgeon technique. The same review also includes a comparison showing 64.8% for methods that added components including stem cells, versus 46.4% for fat alone[1]When numbers are lined up side by side, it is tempting to compare them, but since the evaluation method differs from study to study, they cannot be directly used to determine superiority or inferiority[1].

A meta-analysis that collected retention rates for facial fat grafting also notes that evaluation methods are divided between subjective and objective approaches, and the lack of a standardized measurement method is identified as an issue[2]Ask which measurement method the numbers come from if you encounter an explanation that says 'X% remains' as a definitive claim.

Pitfall 2: Overfilling and palpable nodules

Overfilling is a displacement that is difficult to correct later. In a survey of US practitioners, excessive injection by less experienced physicians and palpable nodules (lumps) were reported as problems.[3]While there is a practice of injecting more than needed in anticipation of absorption, if the excess remains as-is, it can lead to an unnatural appearance.

Nodules can develop after time has passed. Cases have been reported in which, three years after facial fat injection, fat necrosis occurred triggered by cellulitis.[4]There are also reviews summarizing the effects and complications of facial fat injection, and nodule formation is one of the expected outcomes.[5].

Shift 3: Rare but irreversible complications

While uncommon, there are complications you should not undergo without awareness. Cases have been reported of vein occlusion behind the eyes following forehead injection; the same report lists blindness, stroke, asymmetry, skin irregularities, prolonged swelling, fat necrosis, and infection as associated complications[6].

In case reports of arterial occlusion to the eye following forehead injection, most reported cases resulted in permanent vision loss[7]The occurrence of serious complications from injection to the forehead and eyelids has also been noted in surgeon surveys[3]At your consultation, confirm that the doctor explains how the nature of risk changes depending on the injection site.

To reduce regret, what should you decide in advance?

The first is whether to plan for additional injections[1]Since the amount that remains varies, a plan to add more after observing results tends to be more predictable than a plan to complete the result in one session.

The second is which site to inject[6]The third is at what point to evaluate the result[2]Deciding these three things in advance reduces moments of anxiety as you observe the progress.

What to confirm at your consultation

Ask about the difference in risks for each injection site, the approach to additional injections, and the timing of evaluation[6]It is reassuring to confirm in advance the contact information for when you feel a nodule or when redness and pain intensify[4].

How facial fat decreases, skin thickness, and differences in skeletal structure left and right vary from person to person. The numbers listed here are values reported in research and do not indicate how much will remain in your own face. At your consultation, ask specifically what plan exists for how much to inject into which sites, and confirm together with the doctor that there is no gap with your hopes.