What are the hazards of autologous fat filling?

The main purpose of autologous fat filling is to extract fat from one part of oneself and inject it into the part where fat is needed again. During the operation, it is easy to cause damage to local blood vessels of the plastic surgeon, thus causing congestion, redness and other phenomena. If the operation is wrong, it is easy to cause uneven skin and vascular embolism at the filled part.