The experimental validation of free fat grafts in thoracic surgery.

We evaluated the viability of free fat grafts in the thoracic cavity using 3-month old male swine (n = 2). After left caudal lobectomy, 1-3 g of subcutaneous fat tissue harvested via the thoracotomy site was implanted in the chest cavity. At re-thoracotomy 6 weeks after implantation, all of the implanted fat grafts (n = 15) were found to have closely adhered to the parietal pleura and visceral pleura. There was a significant decrease by ∼30% in the weight of the fat grafts after implantation. Regardless of the weight loss, the implanted fat graft showed normal structuring without scar formation in the central area. Our results may suggest that free fat pads, which weighed up to 3 g, were successfully cultured in the thoracic cavity until the implanted tissues integrated into the surrounding tissues. Therefore, the free fat pad can be used as a biomaterial for some purposes in thoracic surgery.