Evaluation of Retropectoral Fat Grafting in Breast Reduction by Magnetic Resonance Imaging: A Pilot Study.

Background One of the challenges in breast reduction is to maintain breast projection with 45% of its volume in the upper pole and 55% in the lower pole. Although widely used in breast surgeries, the behavior of fat grafts is still not completely understood. Objectives To evaluate by magnetic resonance imaging (MRI) the survival of fat transferred to the retropectoral plane in patients undergoing breast reduction, in the search for an oncologically safe procedure with high predictability and reproducibility. Methods This pilot study was conducted with 7 patients who underwent breast reduction combined with fat grafting in the submuscular plane. Aspirated fat was processed by sedimentation. MRI of the breasts was performed preoperatively and at 1 and 6 months postoperatively. Fat survival was calculated as the difference between the volumes of fat measured preoperatively and postoperatively by MRI divided by the volume of grafted fat. Results Fourteen breasts were operated on and received on average 119.6 mL of autologous fat in the submuscular plane. Fat survival rate was 43.9% at 1 month after surgery, decreasing to 23.4% in the late postoperative period. The mean anteroposterior projection of the grafted tissue was 1.51 cm at 1 month postoperatively, decreasing to 1.07 cm in the late postoperative period. Conclusions Retropectoral fat grafting may contribute to maintaining the fullness of the upper pole of the breasts. This is an innovative experimental model for future studies on fat harvesting, preparation, and grafting techniques, allowing the evaluation of fat graft survival. Level of Evidence: 4