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Lipofilling of the lips: ultrastructural evaluation by transmission electron microscopy of injected adipose tissue.

OBJECTIVE
To determine if facial autologous fat grafts preserve the morphologic features of adipocytes and guarantee a successful long-term outcome.


METHODS
In a previous study, we performed lipofilling in 99 patients between January 1, 1999, and December 31, 2001. In all patients, we performed 3 fat injections at 28-day intervals. We injected 0.4 mL of adipose tissue in the parafrenal area of the upper lip for each treatment. After 4 months, we obtained a biopsy specimen from the same area. We performed an ultrastructural evaluation on freshly harvested fat at the time of harvesting, on stored fat (-30 degrees C) at 8-week and 12-month intervals, and on the biopsy specimens obtained 4 months after treatment.


RESULTS
We observed good preservation of the ultrastructure in the harvested tissue. On histologic examination of the parafrenal area 4 months after grafting, some zones of the biopsy specimens showed putative adipocytes, fat cysts, and collagen fibers adequate for volume increase of the treated area. Ultrastructural images showed lipid droplets intermingled in the connective tissue, phagocytes with internal lipid droplets, and well-preserved adipocytes.


CONCLUSIONS
This study demonstrates that by using a less traumatic surgical technique, it is possible to increase the cell survival rate of transplanted fat, thereby maintaining a certain number of viable cells and creating a volume increase in the grafted area. The multiple-stage injection technique seems to be a good method, especially when performed with fat stored at -30 degrees C.