Improving fat transfer viability: the role of aging, body mass index, and harvest site.

[BACKGROUND] Fat grafting remains unpredictable in the clinical setting, and variables that influence adipocyte survival, such as age, body mass index, and specific donor sites, are still not well understood.

[METHODS] Twenty-four female subjects were enrolled in this research after institutional review board approval and signed consent to participate was obtained. Subjects were separated into groups according to (1) age (younger, ≤45 years; and older, ≥46 years) and (2) body mass index (normal weight, body mass index<25; and overweight, body mass index≥25). All fat samples were obtained through dry liposuction of three donor sites: lower abdomen, inner thigh, and flank. They were processed identically for dissociation of adipose tissue and isolation of adipocytes. Adipocyte viability was measured using the Nexcelom Cellometer Auto T4.

[RESULTS] In younger patients, adipocyte viability was greater in the lower abdomen than in the flank; in older patients, this difference was not seen. When lower abdominal fat from younger was compared with that from older patients, the viability was higher in younger patients. However, adipocytes from the flank depot had higher viability in the older group compared with the younger group. Inner thigh fat viability was not significantly different across the two age groups. The authors also found no significant differences in fat viability for any given donor site between the normal weight and overweight body mass index groups.

[CONCLUSIONS] The optimal choice site for fat harvest should take patient age into consideration. In younger patients, both lower abdomen and inner thigh appear to be good options.

[CLINICAL QUESTION/LEVEL OF EVIDENCE] Therapeutic, II.