PURPOSE: Autologous fat grafting is a widely used technique for soft tissue augmentation in facial and breast contouring. However, a significant drawback is that, on average, nearly half of the grafted volume is reabsorbed over time, necessitating the need for repetitive procedures. Here we have designed a cryopreservation device and optimized a protocol for on-site storage of the excess lipoasirate.
METHODS: This study presents an innovative device designed for on-site cryopreservation of lipoaspirate featuring a cylindrical vessel with female Luer ports at both ends compatible with fat harvest and processing equipment. It operates as a closed system for fat washing, reducing contamination risks. We conducted evaluations involving various cryoprotectant combinations, freezing temperatures, and durations. To assess cryopreservation outcomes, we measured cell viability by trypan blue and Calcein-Am staining at different time points post-cryopreservation.
RESULTS: In vitro viability analyses indicated that a cryopreservation agent consisting of 10% DMSO and 2% human serum albumin, stored at -80°C, provided optimal cryopreservation results following a three month period compared to fresh fat. For in-vivo graft retention analysis, Nu/Nu athymic mice were utilized, and human fat cryopreserved for seven days, 21 days, three months, or 11 months was engrafted. After three months, assessments of fat graft weight, volume retention, and histology revealed no significant differences between the comparison groups and freshly harvested fat.
CONCLUSION: This study highlights the clinical application of our device to minimize the need for repeated harvest and to effectively preserve lipoasirate for up to one year.