Comparison of effects of 2 harvesting methods on fat autograft.

Objectives/hypothesis: Fat preparation for vocal-fold injection medialization is typically done by scraping of excised fat or by lipo-aspiration; however, lipo-aspiration is substantially more efficient. Considering this, we compared viability of fat tissues obtained by these two techniques. We also examined whether basic fibroblast growth factor (bFGF) would increase cell proliferation in samples harvested by these methods.

Study Design: Harvesting techniques (scraping and lipo-aspiration) were compared using both human and ferret fat. In vitro assays were used to assess tissue viability and cell proliferation.

Methods: Human (n = 5) and ferret (n = 15) abdominal fat specimens were harvested by scraping and lipo-aspiration, for a total of 40 specimens. Alamar Blue and glycerol-3-phosphate dehydrogenase assays were used to quantitatively assess metabolic activity and cellular damage immediately after harvest. PicoGreen assays assessed cell proliferation by quantifying total DNA in harvested specimens after 0, 14, or 21 days in culture. The effects of bFGF (10 ng/mL) on proliferation were measured for the same timepoints.

Results: The glycerol-3-phosphate dehydrogenase assay indicated that lipo-aspiration caused more initial tissue damage (12 +/- 5 mU/mL) than scraping (5 +/- 3 mU/mL), but cell metabolic activity was similar in both groups based on the Alamar Blue assay. Cell proliferation at 14 and 21 days was significantly higher for lipo-aspirated fat than for scraped fat (92.5 +/- 8.8 vs. 55.1 +/- 1.3 ng DNA at 14 days and 111.1 +/- 10.5 vs. 44.6 +/- 4.1 ng DNA at 21 days). bFGF increased fibroblast-like cell proliferation significantly for both harvesting methods at day 21.

Conclusions: Lipo-aspiration caused more initial damage than scraping, but may yield better long-term viability based on increased proliferation. bFGF may enhance cellularity of the stromal component grafted adipose tissue.