Fatty acid analysis of transplanted adipose tissue.

OBJECTIVE To determine whether autologously transferred human adipose tissue maintains viability in vivo for prolonged periods. DESIGN Six healthy female patients (mean age, 61.5 years; mean body mass index, 23.4 kg/m2) received autologous fat transplants from the gluteus to the nasolabial folds. Subcutaneous fat was sampled from facial and gluteal sites 4 times in 1 year. SETTING Private practice, basic science research center. INTERVENTION After local anesthesia, 10 g of subcutaneous adipose tissue was harvested from the right buttock of each patient. Ten milligrams of adipose tissue was aspirated from the right nasolabial fold. Five grams of gluteal fat was then injected into each nasolabial fold using a uniform monolayer threading technique with no overcorrection. As controls, 10 mg of adipose tissue was obtained from the opposite left buttock and left cheek. Adipose tissue from the transplanted and control facial and gluteal sites was sampled at 4, 6, and 12 months after transplantation. MAIN OUTCOME MEASUREMENTS Gluteal fat has more monounsaturated fatty acids and less saturated fatty acids than facial fat. This unique site-specific fatty acid pattern was used to assess the course of the survival of transplanted adipose tissue in the nasolabial region. In all fat samples, the percent area (weight percentage) was obtained for each fatty acid (C12:0 to C22:6 omega-3) using capillary gas chromatography. Clinical results were also analyzed by macrophotographs. RESULTS As expected, gluteal fat had significantly more monounsaturated fatty acids and less saturated fatty acids than facial fat. In 5 of 6 patients, at 4, 6, and 12 months after transplantation, the fatty acid pattern at the transplanted recipient site was similar to the pattern of the control facial site. However, at 4 months, 1 patient had a fatty acid pattern in the transplant recipient site that was similar to the pattern of her gluteal fat. This pattern persisted for 1 year. Fat retention at the transplant site was corroborated by photographic assessment. CONCLUSIONS Long-term adipocyte survival is an achievable goal following fat transfer. The importance of harvesting and injection techniques as well as adipose tissue characteristics require further study.