Rheological Characterization of Different Fat-Derived Products.

Background: Fat grafting has been widely used to correct soft-tissue volume loss and facial rejuvenation. Recent innovative advances have led to different types of fat-derived products. Although the composition of cells and extracellular matrix within different fat products has been reported, their physical and rheological properties are poorly defined.

Objectives: The authors of this study aim to evaluate the rheological properties of different fat-derived products and assess how these properties change after transplantation.

Methods: In this study, the authors assessed the rheological properties of 4 fat-derived products-adipose matrix complex AMCs, high-density fat (HDF), stromal vascular fraction-gel (SVF-gel), and Coleman fat-before and after transplantation. Key parameters, including elastic modulus (G'), viscous modulus (G″), tan delta (tan δ), and yield stress (τy), were measured using a rheometer.

Results: Before transplantation, AMC exhibited the highest G' and G″, followed by SVF-gel, HDF, and Coleman fat. After transplantation, G' decreased for all products, indicating reduced elasticity, while G″ increased, suggesting increased viscosity. AMC maintained the highest G' and G″ even after 3 months, with SVF-gel and HDF showing similar values. Coleman fat had the lowest G' and G″ at all time points.

Conclusions: Fat-derived products have distinct clinical applications based on their mechanical properties. AMC is ideal for deep structural support, SVF-gel for superficial corrections, and HDF for volume restoration in midface areas with volume loss. Clinicians should select products based on mechanical properties and anatomical needs to optimize outcomes.