Ultra-condensed Fat: A Novel Fat Product for Volume Augmentation

• Published in: Aesthetic plastic surgery Vol. 47; no. 5; pp. 2074 - 2083
• Main Authors: Wu, Weizi, Bi, Xin, Zhao, Jing, Lin, Zhousheng, Lu, Feng, Dong, Ziqing, Li, Ye
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.10.2023; Springer Nature B.V
• Subjects: Adipose Tissue - transplantation; Angiogenesis; Animals; Graft Survival; Medicine; Medicine & Public Health; Mice; Microscopy, Electron, Scanning; Original Article; Otorhinolaryngology; Plastic Surgery; Fat grafting; Fat purification; Volume augmentation
• ISSN: 0364-216X; 1432-5241
• DOI: 10.1007/s00266-023-03383-2

Background Fat transplantation retention rate is individualized and unpredictable. The presence of blood components and oil droplets in the injected lipoaspirate increases inflammation and fibrosis in a dose-dependent manner, and is probably the key factor associated with poor retention. Objectives This study describes a volumetric fat grafting strategy based on optimization of grafts via screening intact fat particles and absorbing free oil droplets and impurities. Methods Centrifuged fat components were analyzed by n -hexane leaching. A special device was applied to de-oil intact fat components and obtain ultra-condensed fat (UCF). UCF was evaluated by scanning electron microscopy, particle size analysis, and flow cytometric analysis. Histological and immunohistochemical changes were investigated in a nude mouse fat graft model over 90 days. Results The lower 50% of centrifuged fat was concentrated to 40% of the original volume to obtain UCF. In UCF, the free oil droplet content was less than 10%, more than 80% of particles were larger than 1000 µm, and architecturally important fat components were present. The retention rate of UCF was significantly higher than that of Coleman fat on day 90 (57.5 ± 2.7% vs. 32.8 ± 2.5%, p < 0.001). Histological analysis detected small preadipocytes with multiple intracellular lipid droplets on day 3 in UCF grafts, indicative of early adipogenesis. Angiogenesis and macrophage infiltration were observed in UCF grafts soon after transplantation. Conclusion Adipose regeneration with UCF involves rapid macrophage infiltration and exit, resulting in angiogenesis and adipogenesis. UCF may serve as a lipofiller which is beneficial for fat regeneration. Level of Evidence IV This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266 .