Mechanical Fractionation, Clinical Application, And Characterization Of Unfiltered Emulsified Fat: A Systematic Review

Purpose The use of SVF in promoting tissue healing and regeneration is expanding in a wide spectrum of regenerative procedures. Anyway, clear evidence of the superiority of one mechanical isolation method over its counterpart is still lacking. This study aims to overview the technical details of mechanical isolation methods, clinical use, and characterization of the unfiltered emulsified fat. Methods A systematic review was performed, screening Pubmed and Cochrane Library for studies reporting emulsification protocol without the filtration step to isolate stromal vascular fraction (SVF). Results Of the 92 studies identified, 12 met the inclusion and exclusion criteria. Articles were categorized according to the fat processing method employed: the emulsification procedure and a combination of centrifugation and emulsification. Studies showed a great heterogeneity in terms of adipose tissue harvesting and methods to emulsificate and centrifugate the lipoaspirate. Unfiltered emulsified fat demonstrated encouraging biological and clinical findings; however, interpretation of outcomes is limited by heterogeneous processing protocols, small clinical cohorts, and the lack of standardized comparative assessments. Conclusion Unfiltered emulsified fat represents a biologically interesting minimally manipulated adipose tissue product with potential regenerative applications. However, current evidence remains insufficient to establish superiority over filtered preparations or other mechanically processed adipose tissue products. Prospective controlled studies using standardized processing protocols and validated biological and clinical outcome measures are required to clarify its translational potential. Summary Mechanical processing of adipose tissue has generated several products with heterogeneous terminology and biological characteristics. This systematic review summarizes current evidence regarding unfiltered emulsified fat, including processing techniques, biological characterization, and clinical applications. Although available studies suggest potential regenerative properties related to preservation of extracellular matrix and stromal components, current evidence remains limited by methodological heterogeneity and the absence of standardized protocols. Further prospective comparative studies are required to define the optimal processing strategies and clinical indications.