Joris van Dongen

41 Comparison of SVF isolation procedures: a systematic review Cell yield Thirteen studies evaluated the cell yield of eighteen different intraoperative isolation procedures 22,66-77 (Table 5A and table 5B). The reported cell yield after those different procedures varied between 0.19 – 11.7 x 10 5 cells per ml in enzymatic intraoperative isolation procedures and between 1.8 – 22.6 x 10 5 cells per ml in non-enzymatic intraoperative isolation procedures. Non-enzymatic intraoperative procedures yielded higher number of cells since the cell yield was based on 1ml of end volume, whereas the enzymatic intraoperative isolation cell yield was based on the obtained pellet per 1 ml start volume of lipoaspirate. Of the enzymatic intraoperative isolation procedures, the Celution system, Multi station and Lipokit system were evaluated by more than one group of authors 70,72-74 . Interestingly, obvious different yields were seen using the same procedure in different studies 70,72-74 . Reproducibility is thereby questioned in our opinion. The cell yield using the enzymatic Celution system was significantly higher as compared to the Lipokit system (p=0.004), the Multi station (p=0.049) and CHA-station (p<0.001) 72 . In contrast, Domenis et al. did not find a statistical difference between the enzymatic Celution system and Lipokit system. Moreover, Aronowitz et al. again compared the enzymatic Celution system with the Lipokit system and Multi station. This time, Multi station and the Lipokit system resulted in significant more cells as compared to the Celution system (p<0.05) 70 . In the non-enzymatic intraoperative isolation procedures, the Squeezed fat, Residual fluid of emulsified fat and Fractionation of fat procedures resulted in the relative highest cell yields per ml harvested lipoaspirate 66,67 . Non-enzymatic intraoperative isolation procedures such as shuffling (5 times and 30 times), the Nanofat procedure and Fastem did not mention the begin and end volumes, so the relative yield by isolation cannot be calculated 68,71,74 . Osinga et al, reported that most of the adipocytes remain intact after shuffling 5 or even 30 times 71 . Consequently, to our opinion, the effect of shuffling only cannot be stated as an isolation procedure. We deem it possible that the lipoaspirate after both two procedures did not differ from the initial lipoaspirate obtained at the start of the procedure. However, the benefit might be at a different level, because shuffling does improve the injectability of lipoaspirates as shown by Tonnard et al. 68 .