Fat grafting has been used for soft tissue repair and filling for more than 100 years. With the advancement of fat grafting technology and improvement of its efficacy as well as the expansion of its application, fat grafting has become a hot topic in plastic surgery. However, the results of fat grafting depend entirely on the surgeon’s skill and experience (surgeon-dependent), and the results of fat grafting vary greatly from surgeon to surgeon, with literature reporting absorption rates as high as 25% to 90% after fat grafting, with many reasons for this disparity, including individual differences, and fat acquisition, treatment, and injection methods all affecting the final result.
The most common methods of fat processing are: centrifugation, washing and filtration, and resting and stratification. The purpose of these treatments is to remove the bad components of the transplanted fat such as: blood (red blood cells), cellular debris, and extracellular free lipid droplets. The free lipid droplets released by the fragmentation of fat cells stimulate an inflammatory response in the body. A small number of droplets may be removed by phagocytosis, while a large number of droplets may cause a foreign body reaction and the formation of an oilcyst (oil sac). The blood component that spills out of the blood vessels is also cleared by the inflammatory reaction, which will reduce the survival of the transplanted fat.
I. Determination of extracellular lipids and water in fat
Study method 1.
Re-centrifugation of fat treated by the three methods with a centrifugal force of 400g for 5 minutes
Results: Determination of moisture in treated fat
Water is still present in the fat treated by static stratification alone, about 24.5% (above), and if transplanted into the body, 24.5% will be absorbed first. That is why I personally have been opposed to pure static separation, as centrifugation is damaging to fat cells.
The results show that static separation and centrifugation cannot effectively remove the fat from the fat, while washing and filtration can effectively remove the fat from the fat The content of extracellular fat in the fat treated by static separation is about 8%, and the content of extracellular fat in the fat treated by centrifugation method is 12%, while the content of extracellular fat in the fat treated by washing and filtration is less than 1%, so washing and filtration can remove the fat droplets.
Study method 2.
Microscopic observation
Microscopic observation showed that the fat treated by resting stratification and centrifugation method contained more red blood cells and grease, and the fat treated by washing and filtration contained grease with red blood cells least white arrow shows red blood cells and black arrow shows free grease droplets.
Study method 3.
Erythrocyte and white fine packet count determination by applying the method of static stratification or centrifugation can remove about 60% of the erythrocytes and white blood cells, the application of washing and filtration can remove 95% of the erythrocytes and white blood cells.
Second, the viability of adipose tissue assay.
Viable adipose tissue stimulated with epinephrine can release glycerol, so the viability of adipose tissue after treatment by different methods was measured by detecting the glycerol content after activation by epinephrine.
The results showed that the viability of washed and filtered fat was better than that of fat treated by centrifugal method and untreated fat
Methods of fat treatment.
I have been engaged in autologous fat grafting for breast augmentation for more than 10 years with better surgical results, and now I find that my method of fat treatment is similar to the findings of the present study. I use moderate cleaning, filtration and concentration, which can effectively remove blood, water and oil from the fat.
The picture on the far right is my finished fat, after centrifugation at 1000 rpm for 10 minutes, I found that there was very little water, clear (indicating clean cleaning and few red blood cells) and very little oil.