The January 2013 Plastic & Reconstructive Surgery Journal had an article “Grading Lipoaspirate: Is There an Optimal density for Fat Grafting?” I know, I know. Sounds very scientific. In English, what they are asking is:
When you centrifuge the fat does it make a difference? And what is the best fat?
Patients ask me all the time why I centifuge the fat for fat transfer. It is a good question, and doctors vary in their opinion on the subject. I do it because I see leaders in the field like Dr. Coleman and Dr. Khouri do it. I was taught to do it. They tell me it helps separate out the “good” fat from the “bad” damaged fat cells. But I haven’t seen a ton of research on the subject, and with all the things we need to do to process the fat in a sterile fashion, it does make you wonder if it is worth it.
This is a study out of NY and Dr. Coleman. They looked at centrifuging fat.
- 10cc of fat were processed.
- 3 minutes at 1200 g
- The bloody and oil factions were discarded
- 1.0cc of the highest density and lowest denisty fat were seaparted for analysis
- High density and low density fat were grafted into mice and harvested for analysis at 2 and 10 weeks to quantify short and long term survival
- The things in fat we like and think help fat survive were analyzed as well: progenitor cells, expression of vascular growth factors, stromal cell derived factor 1a, platelet derived growth factor, adiponectin
Findings? High density fat is better.
- Greater percentages of fat remained at 2 and 10 weeks (85% vs 62% and 61% vs. 42%)
- The high density fat has better blood vessels and less fibrosis
- There were more progenitor cells
- Concentrations of all the vascular growth factors were better (new blood supply = fat lives)
So? So this study indicates there is a reason to centrifuge. It seems to concentrate the fat and the growth factors which help fat survive. It seems from this animal model that the high density fat after centrifuge is better. So I will continue to centrifuge when I use fat for fat transfer to the face, breast, and buttock. I look forward to more studies trying to make fat transfer and fat grafting better and more predictable.