Enhancing the take of injected adipose tissue by a simple method for concentrating fat cells

Injection of aspirated fat for the correction of tissue defects is a common procedure in plastic surgery. The reported rates of fat cell survival vary greatly in the medical literature, and different techniques of harvesting, processing, and reinjecting the fat cells are claimed to be responsible for these differences. However, there is no agreement concerning the best way to process the harvested fat before reinjection. The present study was initiated to examine and evaluate the effect of a simple method of isolating the fat particles on the outcome of fat graft survival. In this study, the nude mouse model was used to examine the survival and take of the fat graft concentrated before injection by the cumbersome recommended closed centrifugation technique in comparison with the authors' recommended open method, using an operating room cotton towel as a platform for concentrating the fat cells and separating them from fluids, oil, and debris. One milliliter of concentrated human fat cells preprocessed by towel separation was injected into the nuchal subcutis of 11 nude mice in the study group, and the same amount of fat that was preprocessed by centrifugation was injected into 11 control mice. Injected fat survived in both groups. No significant differences were found regarding fat graft weight and volume, although a tendency for better survival was noticed in the experimental group. Histologic evaluation of the grafts revealed significantly less fibrosis within the study group, meaning that the quality of the fat grafts was better. The authors found this method to be simple, cheap, and friendly to the surgeon in comparison with traditional processing using the centrifuge.