Fat transfer from one area of the body to another is a form of tissue grafting. Tissue grafting has been used for a very long time by surgeons, first and foremost in skin grafts to treat burn victims, and has excellent results for cosmetic goals as well.
Plastic surgery is a field of innovation, and years ago, plastic surgeons began experimenting with transferring the fat that was obtained during liposuction procedures.
Gradually, the process of fat transfer has much improved. There’s no question that fat transfer works. The only question is, how much difference will you see? When used for reconstructive purposes (i.e., during cancer reconstruction) by plastic surgeons, there are reimbursement codes that exist, and you know that Medicare and the insurance companies don’t like paying for things that don’t work!
In the section below, the factors that make fat transfer succesful will be explained. There is no question that some of the fat is lost after the transfer. These strategies are employed to maximize the portion that survives permanently.
Studies have shown that the success of fat transfer depends on factors during the removal of the fat, such as the aspiration pressure used and the cannula sized used. The donor site (where the fat comes from), itself is not as important. Separation from excess fluid ensures that the surgeon is injecting a higher proportion of fat, and we prefer at our center two rounds of gentle gravity separtion.
Slow, slow, slow is the answer to a high success rate of fat survival. Slow injection while withdrawing the canulae leads to small droplets of fat cells surrounded by cells in the recipient area with whom the new cells will “share” resources such as oxygen and nutrition until they grow their own more secure attachments. Fast injection leads to larger droplets, and those droplets will be too large to be supported by surrounding tissue. Fat injection therefore requires slow injection techniques, and is time-consuming.
The recipient area is very important in determining the success rate of fat transfer. Again, fat grafting is a three-dimentional deposition of fat cells into the donor area, and therefore (somewhat unfairly), the smaller you initially are, the smaller the amount that can be fit in one session. Example: someone with about 200 cc of native breast volume or 500 cc of native buttock volume will not fit as much tissue as someone with larger breasts or buttocks. But do not despair—there's a way around that limitation.
Do not sit too much on your buttocks for one week after surgery. A good recovery from surgery will assure a greater proportion of fat survivial. Conversely, an infection in the recipient area, while uncommon, may decrease fat survival.