A person’s own fat may be used to improve the appearance of his or her body by moving it from an area of excess (or where it is less desired, such as the thighs, hips or abdomen) to an area that has lost tissue volume due to aging, trauma, surgery, certain diseases, birth defects, or other causes.
Ideal candidates are in good health, and have excess fat in some parts of the body and too little in other regions. Fat grafting is most often used for the face, breasts and buttocks. Typically, the transferred fat results in a significant increase in volume of the body site being treated.
Fat for lipoinjection, also called fat transfer, is removed from unwanted areas of the body by a narrow blunt tip surgical instrument with side holes, called a cannula, through a small incision. The fat is then cleaned with sterile saline solution before being restored to the body. The fat is then injected into the desired area using either a smaller cannula or needle, or it may be placed directly through an incision. Since some of the fat that is transferred does not remain over time, your surgeon may inject more than is ultimately needed to achieve the desired end result. Over a few weeks, the amount of transferred fat will decrease.
There is a limit of how much fat can be safely injected into one area. The amount of fat that remains over time is variable from patient to patient. For some patients, more fat or other fillers may need to be transferred in a subsequent surgery to maintain or supplement the desired results.
Fat transfer procedures are performed using a local anesthetic, with or without IV sedation or general anesthesia, depending on the extent of the procedure and recommendations of your surgeon.
Alternative forms of nonsurgical and surgical volume management consist of injections of FDA-approved injectable fillers, or occasionally implants.
Fillers include hyaluronic acid “HA” (Restylane, Juvederm), polylactic acid (Sculptra), calcium hydroxyapatite (Radiesse) and other fillers, use of man-made implants or other surgical procedures that transfer vascularized fat from body tissues nearby (flaps).
In general, injectable off-the-shelf fillers and fat are used for smaller areas such as in the face, whereas only fat is used to inject into larger areas such as the buttocks due to the quantity required to make the desired change.
Specific Risks of Fat Transfer Procedures
Every procedure involves a certain amount of risk. When choosing to undergo a procedure, an individual must weigh its risks against its potential benefits. Although the majority of our patients do not experience these complications, you should discuss all of your concerns with your plastic surgeon.
Infection — Infection may occur after any surgery and may rarely occur after fat transfer. The rate of infection increases with the amount of injected fat, but the overall rate still remains very low due to routine use of sterile technique and prophylactic antibiotics. Complication rates are higher in smokers, those with diabetes, and with multiple procedures.
Excessive Bleeding — Although bruising after surgery is common and occasionally prolonged, excessive bleeding is unusual during or after surgery. Unapproved medications and supplements, or strenuous physical activity too soon after surgery, can increase the chance of bleeding and complications in general. It is important to follow your surgeon’s postoperative instructions.
Change in Appearance — Typically the transferred fat loses some of its volume over time and then becomes stable. It is possible that more fat transfer treatments may be needed to maintain the desired appearance. It is important to understand that more than one treatment may be needed for optimal results. Additional costs are associated with repeated treatments.
Firmness and Lumpiness — While most transferred fat results in a natural feel, it is possible that some or all of the fat may become firm, hard, or lumpy. If some of the fat does not survive the transfer, it may result in fat necrosis (death of transferred fat tissue), causing firmness and discomfort. Oil cysts may also form at the site of the transferred fat. Needle aspiration or surgery may be required to improve such conditions.
Fluid Accumulation (Seroma) — After fat grafting with or without implant placement, body fluids occasionally collect beneath the skin called a seroma which can delay wound healing. If the fluid accumulation is significant, your plastic surgeon may aspirate the fluid with a small needle as an office procedure one or more times.
Fat Absorption Viability — Approximately 20-40% of injected fat does not remain and re-absorbs. Fat survival depends on the location of injection, age, co-morbid disease factors, smoking, weight gain or loss, and technical factors including expertise of the surgeon. Gentle massaging over the buttock area helps even out and smooths these areas during the recovery phase.
Skin Irregularities or Dimples — Contour irregularities, including bumps, dimples, and asymmetric fullness, as well as depressions or fullness in the skin may occur after fat transfer and liposuction. Visible and palpable wrinkling of skin may occur depending on skin elasticity. Postoperative massaging is often helpful in smoothing these areas.
Fat Necrosis — The areas where fat is transferred to and from may experience fat compromise or fat death that can lead to surface irregularities or result in fat calcification and produce areas of palpable firmness, “bumps”. Additional surgery to remove areas of fat necrosis may be necessary. This may result in contour irregularities.
Skin Loss (Skin Death) — This is a rare occurrence. The skin about the site of surgery or at the incision site may become necrotic or ‘die’. When this happens, skin may change color and slough off. If it is not a full thickness injury the skin will grow back, otherwise a wound will form and heal slowly. This may require further surgical and medical management.
Contour Asymmetry — The two halves of the body are never symmetric. Therefore, following fat transfers, these asymmetries may persist and appear as difference between the contour and volume of the two sides.
Long Term Effects — Subsequent changes in the shape or appearance of the area where the fat was removed or placed will occur as the results of aging, weight loss or gain, or other circumstance not related to the fat transfer procedures.
Fatty Cyst Formation — The transferred fat may form small fat clumps or oil cysts. This may interfere with the interpretation of future radiologic studies of breasts, and rarely, may need to be aspirated or removed.
Fat Transfers to Breast — Fat transfers have been widely used to improve the appearance of breast reconstruction. There are some potential concerns with regard to breast cancer detection. Since the transferred fat may become firm and cause lumps, it may be necessary to have radiological studies performed to be sure these lumps are not due to cancer. However, there is presently evidence nor nor reason to believe that fat transfer procedures may cause breast cancer.